Sample records for intercellular adhesive structures

  1. Cellular level robotic surgery: Nanodissection of intermediate filaments in live keratinocytes.

    PubMed

    Yang, Ruiguo; Song, Bo; Sun, Zhiyong; Lai, King Wai Chiu; Fung, Carmen Kar Man; Patterson, Kevin C; Seiffert-Sinha, Kristina; Sinha, Animesh A; Xi, Ning

    2015-01-01

    We present the nanosurgery on the cytoskeleton of live cells using AFM based nanorobotics to achieve adhesiolysis and mimic the effect of pathophysiological modulation of intercellular adhesion. Nanosurgery successfully severs the intermediate filament bundles and disrupts cell-cell adhesion similar to the desmosomal protein disassembly in autoimmune disease, or the cationic modulation of desmosome formation. Our nanomechanical analysis revealed that adhesion loss results in a decrease in cellular stiffness in both cases of biochemical modulation of the desmosome junctions and mechanical disruption of intercellular adhesion, supporting the notion that intercellular adhesion through intermediate filaments anchors the cell structure as focal adhesion does and that intermediate filaments are integral components in cell mechanical integrity. The surgical process could potentially help reveal the mechanism of autoimmune pathology-induced cell-cell adhesion loss as well as its related pathways that lead to cell apoptosis. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Adherens junction turnover: regulating adhesion through cadherin endocytosis, degradation, and recycling

    PubMed Central

    Nanes, Benjamin A.; Kowalczyk, Andrew P.

    2014-01-01

    Adherens junctions are important mediators of intercellular adhesion, but they are not static structures. They are regularly formed, broken, and rearranged in a variety of situations, requiring changes in the amount of cadherins, the main adhesion molecule in adherens junctions, present at the cell surface. Thus, endocytosis, degradation, and recycling of cadherins are crucial for dynamic regulation of adherens junctions and control of intercellular adhesion. In this chapter, we review the involvement of cadherin endocytosis in development and disease. We discuss the various endocytic pathways available to cadherins, the adaptors involved, and the sorting of internalized cadherin for recycling or lysosomal degradation. In addition, we review the regulatory pathways controlling cadherin endocytosis and degradation, including regulation of cadherin endocytosis by catenins, cadherin ubiquitination, and growth factor receptor signaling pathways. Lastly, we discuss the proteolytic cleavage of cadherins at the plasma membrane. PMID:22674073

  3. Keratins Regulate p38MAPK-Dependent Desmoglein Binding Properties in Pemphigus

    PubMed Central

    Vielmuth, Franziska; Walter, Elias; Fuchs, Michael; Radeva, Mariya Y.; Buechau, Fanny; Magin, Thomas M.; Spindler, Volker; Waschke, Jens

    2018-01-01

    Keratins are crucial for the anchorage of desmosomes. Severe alterations of keratin organization and detachment of filaments from the desmosomal plaque occur in the autoimmune dermatoses pemphigus vulgaris and pemphigus foliaceus (PF), which are mainly caused by autoantibodies against desmoglein (Dsg) 1 and 3. Keratin alterations are a structural hallmark in pemphigus pathogenesis and correlate with loss of intercellular adhesion. However, the significance for autoantibody-induced loss of intercellular adhesion is largely unknown. In wild-type (wt) murine keratinocytes, pemphigus autoantibodies induced keratin filament retraction. Under the same conditions, we used murine keratinocytes lacking all keratin filaments (KtyII k.o.) as a model system to dissect the role of keratins in pemphigus. KtyII k.o. cells show compromised intercellular adhesion without antibody (Ab) treatment, which was not impaired further by pathogenic pemphigus autoantibodies. Nevertheless, direct activation of p38MAPK via anisomycin further decreased intercellular adhesion indicating that cell cohesion was not completely abrogated in the absence of keratins. Direct inhibition of Dsg3, but not of Dsg1, interaction via pathogenic autoantibodies as revealed by atomic force microscopy was detectable in both cell lines demonstrating that keratins are not required for this phenomenon. However, PF-IgG shifted Dsg1-binding events from cell borders toward the free cell surface in wt cells. This led to a distribution pattern of Dsg1-binding events similar to KtyII k.o. cells under resting conditions. In keratin-deficient keratinocytes, PF-IgG impaired Dsg1-binding strength, which was not different from wt cells under resting conditions. In addition, pathogenic autoantibodies were capable of activating p38MAPK in both KtyII wt and k.o. cells, the latter of which already displayed robust p38MAPK activation under resting conditions. Since inhibition of p38MAPK blocked autoantibody-induced loss of intercellular adhesion in wt cells and restored baseline cell cohesion in keratin-deficient cells, we conclude that p38MAPK signaling is (i) critical for regulation of cell adhesion, (ii) regulated by keratins, and (iii) targets both keratin-dependent and -independent mechanisms. PMID:29616033

  4. Structural and functional diversity of cadherin at the adherens junction

    PubMed Central

    2011-01-01

    Adhesion between cells is essential to the evolution of multicellularity. Indeed, morphogenesis in animals requires firm but flexible intercellular adhesions that are mediated by subcellular structures like the adherens junction (AJ). A key component of AJs is classical cadherins, a group of transmembrane proteins that maintain dynamic cell–cell associations in many animal species. An evolutionary reconstruction of cadherin structure and function provides a comprehensive framework with which to appreciate the diversity of morphogenetic mechanisms in animals. PMID:21708975

  5. Connexin 32 and its derived homotypic gap junctional intercellular communication inhibit the migration and invasion of transfected HeLa cells via enhancement of intercellular adhesion.

    PubMed

    Yang, Jie; Liu, Bing; Wang, Qin; Yuan, Dongdong; Hong, Xiaoting; Yang, Yan; Tao, Liang

    2011-01-01

    The effects of connexin (Cx) and its derived homotypic gap junctional intercellular communication (GJIC) between tumor cells on the invasion of metastatic cancers and the underlying mechanisms remain unclear. In this study, we investigated the influence of Cx32 and the homotypic GJIC mediated by this Cx on the migration, invasion and intercellular adhesion of transfected HeLa cells. The expression of Cx32 significantly increased cell adhesion and inhibited migration and invasion. The inhibition of GJIC by oleamide, a widely used GJIC inhibitor, reduced the enhanced adhesion and partly reversed the decreased migration and invasion that had been induced by Cx32 expression. Blockage of the p38 and extracellular signal-regulated kinase 1 and 2 mitogen-activated protein kinase (ERK1/2 MAPKs) pathways using their specific inhibitors attenuated the effects of Cx32, but not those of GJIC, on cell adhesion, migration and invasion. These results indicate that the homotypic GJIC mediated by Cx32, as well as the Cx itself, inhibit cell migration and invasion, most likely through the elevation of intercellular adhesion. The suppressive effect of Cx32 on the migration and invasion of cancer cells, but not that of its derived homotypic GJIC, partly depends on the activation of the p38 and the ERK1/2 MAPKs pathways.

  6. Increase in the adhesion molecule P-selectin in endothelium overlying atherosclerotic plaques. Coexpression with intercellular adhesion molecule-1.

    PubMed Central

    Johnson-Tidey, R. R.; McGregor, J. L.; Taylor, P. R.; Poston, R. N.

    1994-01-01

    P-selectin (GMP-140) is an adhesion molecule present within endothelial cells that is rapidly translocated to the cell membrane upon activation, where it mediates endothelial-leukocyte interactions. Immunohistochemical analysis of human atherosclerotic plaques has shown strong expression of P-selectin by the endothelium overlying active atherosclerotic plaques. P-selectin is not, however, detected in normal arterial endothelium or in endothelium overlying inactive fibrous plaques. Color image analysis was used to quantitate the degree of P-selectin expression in the endothelium and demonstrates a statistically significant increase in P-selectin expression by atherosclerotic endothelial cells. Double immunofluorescence shows that some of this P-selectin is expressed on the luminal surface of the endothelial cells. Previous work has demonstrated a significant up-regulation in the expression of the intercellular adhesion molecule-1 in atherosclerotic endothelium and a study on the expression of intercellular adhesion molecule-1 and P-selectin in atherosclerosis shows a highly positive correlation. These results suggest that the selective and cooperative expression of P-selectin and intercellular adhesion molecule-1 may be involved in the recruitment of monocytes into sites of atherosclerosis. Images Figure 1 Figure 3 Figure 4 Figure 5 PMID:7513951

  7. Kinetic Measurements Reveal Enhanced Protein-Protein Interactions at Intercellular Junctions

    PubMed Central

    Shashikanth, Nitesh; Kisting, Meridith A.; Leckband, Deborah E.

    2016-01-01

    The binding properties of adhesion proteins are typically quantified from measurements with soluble fragments, under conditions that differ radically from the confined microenvironment of membrane bound proteins in adhesion zones. Using classical cadherin as a model adhesion protein, we tested the postulate that confinement within quasi two-dimensional intercellular gaps exposes weak protein interactions that are not detected in solution binding assays. Micropipette-based measurements of cadherin-mediated, cell-cell binding kinetics identified a unique kinetic signature that reflects both adhesive (trans) bonds between cadherins on opposing cells and lateral (cis) interactions between cadherins on the same cell. In solution, proposed lateral interactions were not detected, even at high cadherin concentrations. Mutations postulated to disrupt lateral cadherin association altered the kinetic signatures, but did not affect the adhesive (trans) binding affinity. Perturbed kinetics further coincided with altered cadherin distributions at junctions, wound healing dynamics, and paracellular permeability. Intercellular binding kinetics thus revealed cadherin interactions that occur within confined, intermembrane gaps but not in solution. Findings further demonstrate the impact of these revealed interactions on the organization and function of intercellular junctions. PMID:27009566

  8. The desmosome and pemphigus

    PubMed Central

    2008-01-01

    Desmosomes are patch-like intercellular adhering junctions (“maculae adherentes”), which, in concert with the related adherens junctions, provide the mechanical strength to intercellular adhesion. Therefore, it is not surprising that desmosomes are abundant in tissues subjected to significant mechanical stress such as stratified epithelia and myocardium. Desmosomal adhesion is based on the Ca2+-dependent, homo- and heterophilic transinteraction of cadherin-type adhesion molecules. Desmosomal cadherins are anchored to the intermediate filament cytoskeleton by adaptor proteins of the armadillo and plakin families. Desmosomes are dynamic structures subjected to regulation and are therefore targets of signalling pathways, which control their molecular composition and adhesive properties. Moreover, evidence is emerging that desmosomal components themselves take part in outside-in signalling under physiologic and pathologic conditions. Disturbed desmosomal adhesion contributes to the pathogenesis of a number of diseases such as pemphigus, which is caused by autoantibodies against desmosomal cadherins. Beside pemphigus, desmosome-associated diseases are caused by other mechanisms such as genetic defects or bacterial toxins. Because most of these diseases affect the skin, desmosomes are interesting not only for cell biologists who are inspired by their complex structure and molecular composition, but also for clinical physicians who are confronted with patients suffering from severe blistering skin diseases such as pemphigus. To develop disease-specific therapeutic approaches, more insights into the molecular composition and regulation of desmosomes are required. PMID:18386043

  9. Increased soluble vascular cell adhesion molecule-1 plasma levels and soluble intercellular adhesion molecule-1 during antiretroviral therapy interruption and retention of elevated soluble vascular cellular adhesion molecule-1 levels following resumption of antiretroviral therapy.

    PubMed

    Papasavvas, Emmanouil; Azzoni, Livio; Pistilli, Maxwell; Hancock, Aidan; Reynolds, Griffin; Gallo, Cecile; Ondercin, Joe; Kostman, Jay R; Mounzer, Karam; Shull, Jane; Montaner, Luis J

    2008-06-19

    We investigated the effect of short viremic episodes on soluble markers associated with endothelial stress and cardiovascular disease risk in chronically HIV-1-infected patients followed during continuous antiretroviral therapy, antiretroviral therapy interruption and antiretroviral therapy resumption. We assessed changes in plasma levels of von Willebrand factor, soluble vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 by enzyme-linked immunosorbent assay, as well as T-cell activation (CD8+/CD38+, CD8+/HLA-DR+ and CD3+/CD95+) by flow cytometry, in 36 chronically HIV-1-infected patients participating in a randomized study. Patients were divided into the following three groups: a, on continuous antiretroviral therapy; b, on a 6-week antiretroviral therapy interruption; or c, on antiretroviral therapy interruption extended to the achievement of viral set point. Although all measurements remained stable over a 40-week follow-up on antiretroviral therapy, plasma levels of soluble vascular cell adhesion molecule-1 (P < 0.0001) and soluble intercellular adhesion molecule-1 (P = 0.003) increased during treatment interruption in correlation with viral rebound and T-cell activation. No significant changes in von Willebrand factor were observed in any of the groups. After resuming antiretroviral therapy, soluble vascular cell adhesion molecule-1 levels remained elevated even after achievement of viral suppression to less than 50 copies/ml. The prompt rise in plasma soluble vascular cell adhesion molecule-1 and soluble intercellular adhesion molecule-1 upon viral rebound suggests an acute increase in endothelial stress upon treatment interruption, which may persists after viral resuppression of virus. Thus, viral replication during short-term treatment interruption may increase the overall cardiovascular risk during and beyond treatment interruption.

  10. Quantitative measurements of intercellular adhesion between a macrophage and cancer cells using a cup-attached AFM chip.

    PubMed

    Kim, Hyonchol; Yamagishi, Ayana; Imaizumi, Miku; Onomura, Yui; Nagasaki, Akira; Miyagi, Yohei; Okada, Tomoko; Nakamura, Chikashi

    2017-07-01

    Intercellular adhesion between a macrophage and cancer cells was quantitatively measured using atomic force microscopy (AFM). Cup-shaped metal hemispheres were fabricated using polystyrene particles as a template, and a cup was attached to the apex of the AFM cantilever. The cup-attached AFM chip (cup-chip) approached a murine macrophage cell (J774.2), the cell was captured on the inner concave of the cup, and picked up by withdrawing the cup-chip from the substrate. The cell-attached chip was advanced towards a murine breast cancer cell (FP10SC2), and intercellular adhesion between the two cells was quantitatively measured. To compare cell adhesion strength, the work required to separate two adhered cells (separation work) was used as a parameter. Separation work was almost 2-fold larger between a J774.2 cell and FP10SC2 cell than between J774.2 cell and three additional different cancer cells (4T1E, MAT-LyLu, and U-2OS), two FP10SC2 cells, or two J774.2 cells. FP10SC2 was established from 4T1E as a highly metastatic cell line, indicates separation work increased as the malignancy of cancer cells became higher. One possible explanation of the strong adhesion of macrophages to cancer cells observed in this study is that the measurement condition mimicked the microenvironment of tumor-associated macrophages (TAMs) in vivo, and J774.2 cells strongly expressed CD204, which is a marker of TAMs. The results of the present study, which were obtained by measuring cell adhesion strength quantitatively, indicate that the fabricated cup-chip is a useful tool for measuring intercellular adhesion easily and quantitatively. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Plasmodium falciparum Adhesion on Human Brain Microvascular Endothelial Cells Involves Transmigration-Like Cup Formation and Induces Opening of Intercellular Junctions

    PubMed Central

    Jambou, Ronan; Combes, Valery; Jambou, Marie-Jose; Weksler, Babeth B.; Couraud, Pierre-Olivier; Grau, Georges E.

    2010-01-01

    Cerebral malaria, a major cause of death during malaria infection, is characterised by the sequestration of infected red blood cells (IRBC) in brain microvessels. Most of the molecules implicated in the adhesion of IRBC on endothelial cells (EC) are already described; however, the structure of the IRBC/EC junction and the impact of this adhesion on the EC are poorly understood. We analysed this interaction using human brain microvascular EC monolayers co-cultured with IRBC. Our study demonstrates the transfer of material from the IRBC to the brain EC plasma membrane in a trogocytosis-like process, followed by a TNF-enhanced IRBC engulfing process. Upon IRBC/EC binding, parasite antigens are transferred to early endosomes in the EC, in a cytoskeleton-dependent process. This is associated with the opening of the intercellular junctions. The transfer of IRBC antigens can thus transform EC into a target for the immune response and contribute to the profound EC alterations, including peri-vascular oedema, associated with cerebral malaria. PMID:20686652

  12. Hydrodynamic shear shows distinct roles for LFA-1 and Mac-1 in neutrophil adhesion to intercellular adhesion molecule-1.

    PubMed

    Neelamegham, S; Taylor, A D; Burns, A R; Smith, C W; Simon, S I

    1998-09-01

    The binding of neutrophil beta2 integrin to intercellular adhesion molecule-1 (ICAM-1) expressed on the inflamed endothelium is critical for neutrophil arrest at sites of tissue inflammation. To quantify the strength and kinetics of this interaction, we measured the adhesion between chemotactically stimulated neutrophils and ICAM-1-transfected mouse cells (E3-ICAM) in suspension in a cone-plate viscometer at shear rates typical of venular blood flow (100 s-1 to 500 s-1). The kinetics of aggregation were fit with a mathematical model based on two-body collision theory. This enabled estimation of adhesion efficiency, defined as the probability with which collisions between cells resulted in firm adhesion. The efficiency of beta2-integrin-dependent adhesion was highest ( approximately 0.2) at 100 s-1 and it decreased to approximately zero at 400 s-1. Both LFA-1 and Mac-1 contributed equally to adhesion efficiency over the initial 30 seconds of stimulation, but adhesion was entirely Mac-1-dependent by 120 seconds. Two hydrodynamic parameters were observed to influence integrin-dependent adhesion efficiency: the level of shear stress and the intercellular contact duration. Below a critical shear stress (<2 dyn/cm2), contact duration predominantly limited adhesion efficiency. The estimated minimum contact duration for beta2-integrin binding was approximately 6.5 ms. Above the critical shear stress (>2 dyn/cm2), the efficiency of neutrophil adhesion to E3-ICAM was limited by both the contact duration and the tensile stress. We conclude that at low shear, neutrophil adhesion is modulated independently through either LFA-1 or Mac-1, which initially contribute with equal efficiency, but differ over the duration of chemotactic stimulation. Copyright 1998 by The American Society of Hematology.

  13. Epithelial self-defense against cancer.

    PubMed

    Yamauchi, Hajime; Fujita, Yasuyuki

    2012-11-01

    It is not clearly understood what happens at the interface between normal and transformed epithelial cells at the first step of carcinogenesis. A recent study reveals that the organized epithelial structure suppresses clonal expansion of transformed cells. Translocation from the epithelium or perturbation of intercellular adhesions may be required for transformed cells to evade the suppressive environments.

  14. Endothelial cell regulation of leukocyte infiltration in inflammatory tissues

    PubMed Central

    Mantovani, A.; Introna, M.; Dejana, E.

    1995-01-01

    Endothelial cells play an important, active role in the onset and regulation of inflammatory and immune reactions. Through the production of chemokines they attract leukocytes and activate their adhesive receptors. This leads to the anchorage of leukocytes to the adhesive molecules expressed on the endothelial surface. Leukocyte adhesion to endothelial cells is frequently followed by their extravasation. The mechanisms which regulate the passage of leukocytes through endothelial clefts remain to be clarified. Many indirect data suggest that leukocytes might transfer signals to endothelial cells both through the release of active agents and adhesion to the endothelial cell surface. Adhesive molecules (such as PECAM) on the endothelial cell surface might also ‘direct’ leukocytes through the intercellular junction by haptotaxis. The information available on the molecular structure and functional properties of endothelial chemokines, adhesive molecules or junction organization is still fragmentary. Further work is needed to clarify how they interplay in regulating leukocyte infiltration into tissues. PMID:18475659

  15. Crystal structure of the Haemophilus influenzae Hap adhesin reveals an intercellular oligomerization mechanism for bacterial aggregation

    PubMed Central

    Meng, Guoyu; Spahich, Nicole; Kenjale, Roma; Waksman, Gabriel; St Geme, Joseph W

    2011-01-01

    Bacterial biofilms are complex microbial communities that are common in nature and are being recognized increasingly as an important determinant of bacterial virulence. However, the structural determinants of bacterial aggregation and eventual biofilm formation have been poorly defined. In Gram-negative bacteria, a major subgroup of extracellular proteins called self-associating autotransporters (SAATs) can mediate cell–cell adhesion and facilitate biofilm formation. In this study, we used the Haemophilus influenzae Hap autotransporter as a prototype SAAT to understand how bacteria associate with each other. The crystal structure of the H. influenzae HapS passenger domain (harbouring the SAAT domain) was determined to 2.2 Å by X-ray crystallography, revealing an unprecedented intercellular oligomerization mechanism for cell–cell interaction. The C-terminal SAAT domain folds into a triangular-prism-like structure that can mediate Hap–Hap dimerization and higher degrees of multimerization through its F1–F2 edge and F2 face. The intercellular multimerization can give rise to massive buried surfaces that are required for overcoming the repulsive force between cells, leading to bacterial cell–cell interaction and formation of complex microcolonies. PMID:21841773

  16. Indomethacin induced gastropathy in CD18, intercellular adhesion molecule 1, or P-selectin deficient mice

    PubMed Central

    Morise, Z; Granger, D; Fuseler, J; Anderson, D; Grisham, M

    1999-01-01

    BACKGROUND—Neutrophil-endothelial cell interactions are thought to play a critical role in the pathophysiology of non-steroidal anti-inflammatory drug (NSAID) induced gastropathy.
AIMS—To optimise a mouse model of NSAID induced gastropathy and to evaluate the importance of adhesion molecules using adhesion molecule deficient mice.
METHODS—Gastropathy was induced in C57BL/6 mice or their adhesion molecule deficient counterparts via oral administration of indomethacin (20 mg/kg). Lesion scores, mucosal permeability, and histopathology were used to assess gastric mucosal injury.
RESULTS—Intragastric administration of indomethacin induced linear haemorrhagic mucosal lesions, primarily in the corpus of the stomach that were first observed at six hours. These lesions continued to develop over the next six hours with maximal lesion scores and mucosal permeabilities at 12 hours. When indomethacin was administered to mice deficient in CD18, intercellular adhesion molecule 1 (ICAM-1), or P-selectin, there were significant decreases in lesion scores compared with their C57BL/6 controls. In addition, mucosal permeabilities were found to be significantly lower in CD18 or ICAM-1 deficient mice observed at 12 hours.
CONCLUSION—Certain leucocyte and endothelial cell adhesion molecules are important determinants for full expression of indomethacin induced gastropathy. It is proposed that this modification of the mouse model may be useful for the investigation of other pathophysiological mechanisms of NSAID induced gastropathy.


Keywords: indomethacin; gastropathy; cyclooxygenase; intercellular adhesion molecule; VCAM; vascular cell adhesion molecule; P-selectin PMID:10486359

  17. Inhibitors of adhesion molecules expression; the synthesis and pharmacological properties of 10H-pyrazino[2,3-b][1,4]benzothiazine derivatives.

    PubMed

    Kaneko, Toshihiko; Clark, Richard S J; Ohi, Norihito; Kawahara, Tetsuya; Akamatsu, Hiroshi; Ozaki, Fumihiro; Kamada, Atsushi; Okano, Kazuo; Yokohama, Hiromitsu; Muramoto, Kenzo; Ohkuro, Masayoshi; Takenaka, Osamu; Kobayashi, Seiichi

    2002-07-01

    During a search for novel, orally-active inhibitors of upregulation of adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1), we found a new series of 10H-pyrazino[2,3-b][1,4]benzothiazine derivatives to be potent ICAM-1 inhibitors. Of these compounds, N-[1-(10H-Pyrazino[2,3-b][1,4]benzothiazin-8-ylmethyl)piperidin-4-yl]-N',N'-dimethylsulfamide 7p showed the potent oral inhibitory activities against neutrophil migration in a murine interleukin-1 (IL-1) induced paw inflammation model. The synthesis and structure-activity relationships of these amide derivatives are described.

  18. Intercellular Adhesion Molecule-5 Induces Dendritic Outgrowth by Homophilic Adhesion

    PubMed Central

    Tian, Li; Nyman, Henrietta; Kilgannon, Patrick; Yoshihara, Yoshihiro; Mori, Kensaku; Andersson, Leif C.; Kaukinen, Sami; Rauvala, Heikki; Gallatin, W. Michael; Gahmberg, Carl G.

    2000-01-01

    Intercellular adhesion molecule-5 (ICAM-5) is a dendritically polarized membrane glycoprotein in telencephalic neurons, which shows heterophilic binding to leukocyte β2-integrins. Here, we show that the human ICAM-5 protein interacts in a homophilic manner through the binding of the immunoglobulin domain 1 to domains 4–5. Surface coated ICAM-5-Fc promoted dendritic outgrowth and arborization of ICAM- 5–expressing hippocampal neurons. During dendritogenesis in developing rat brain, ICAM-5 was in monomer form, whereas in mature neurons it migrated as a high molecular weight complex. The findings indicate that its homophilic binding activity was regulated by nonmonomer/monomer transition. Thus, ICAM-5 displays two types of adhesion activity, homophilic binding between neurons and heterophilic binding between neurons and leukocytes. PMID:10893271

  19. Specificity of cell–cell adhesion by classical cadherins: Critical role for low-affinity dimerization through β-strand swapping

    PubMed Central

    Chen, Chien Peter; Posy, Shoshana; Ben-Shaul, Avinoam; Shapiro, Lawrence; Honig, Barry H.

    2005-01-01

    Cadherins constitute a family of cell-surface proteins that mediate intercellular adhesion through the association of protomers presented from juxtaposed cells. Differential cadherin expression leads to highly specific intercellular interactions in vivo. This cell–cell specificity is difficult to understand at the molecular level because individual cadherins within a given subfamily are highly similar to each other both in sequence and structure, and they dimerize with remarkably low binding affinities. Here, we provide a molecular model that accounts for these apparently contradictory observations. The model is based in part on the fact that cadherins bind to one another by “swapping” the N-terminal β-strands of their adhesive domains. An inherent feature of strand swapping (or, more generally, the domain swapping phenomenon) is that “closed” monomeric conformations act as competitive inhibitors of dimer formation, thus lowering affinities even when the dimer interface has the characteristics of high-affinity complexes. The model describes quantitatively how small affinity differences between low-affinity cadherin dimers are amplified by multiple cadherin interactions to establish large specificity effects at the cellular level. It is shown that cellular specificity would not be observed if cadherins bound with high affinities, thus emphasizing the crucial role of strand swapping in cell–cell adhesion. Numerical estimates demonstrate that the strength of cellular adhesion is extremely sensitive to the concentration of cadherins expressed at the cell surface. We suggest that the domain swapping mechanism is used by a variety of cell-adhesion proteins and that related mechanisms to control affinity and specificity are exploited in other systems. PMID:15937105

  20. Drosophila E-cadherin is required for the maintenance of ring canals anchoring to mechanically withstand tissue growth.

    PubMed

    Loyer, Nicolas; Kolotuev, Irina; Pinot, Mathieu; Le Borgne, Roland

    2015-10-13

    Intercellular bridges called "ring canals" (RCs) resulting from incomplete cytokinesis play an essential role in intercellular communication in somatic and germinal tissues. During Drosophila oogenesis, RCs connect the maturing oocyte to nurse cells supporting its growth. Despite numerous genetic screens aimed at identifying genes involved in RC biogenesis and maturation, how RCs anchor to the plasma membrane (PM) throughout development remains unexplained. In this study, we report that the clathrin adaptor protein 1 (AP-1) complex, although dispensable for the biogenesis of RCs, is required for the maintenance of the anchorage of RCs to the PM to withstand the increased membrane tension associated with the exponential tissue growth at the onset of vitellogenesis. Here we unravel the mechanisms by which AP-1 enables the maintenance of RCs' anchoring to the PM during size expansion. We show that AP-1 regulates the localization of the intercellular adhesion molecule E-cadherin and that loss of AP-1 causes the disappearance of the E-cadherin-containing adhesive clusters surrounding the RCs. E-cadherin itself is shown to be required for the maintenance of the RCs' anchorage, a function previously unrecognized because of functional compensation by N-cadherin. Scanning block-face EM combined with transmission EM analyses reveals the presence of interdigitated, actin- and Moesin-positive, microvilli-like structures wrapping the RCs. Thus, by modulating E-cadherin trafficking, we show that the sustained E-cadherin-dependent adhesion organizes the microvilli meshwork and ensures the proper attachment of RCs to the PM, thereby counteracting the increasing membrane tension induced by exponential tissue growth.

  1. Drosophila E-cadherin is required for the maintenance of ring canals anchoring to mechanically withstand tissue growth

    PubMed Central

    Loyer, Nicolas; Kolotuev, Irina; Pinot, Mathieu; Le Borgne, Roland

    2015-01-01

    Intercellular bridges called “ring canals” (RCs) resulting from incomplete cytokinesis play an essential role in intercellular communication in somatic and germinal tissues. During Drosophila oogenesis, RCs connect the maturing oocyte to nurse cells supporting its growth. Despite numerous genetic screens aimed at identifying genes involved in RC biogenesis and maturation, how RCs anchor to the plasma membrane (PM) throughout development remains unexplained. In this study, we report that the clathrin adaptor protein 1 (AP-1) complex, although dispensable for the biogenesis of RCs, is required for the maintenance of the anchorage of RCs to the PM to withstand the increased membrane tension associated with the exponential tissue growth at the onset of vitellogenesis. Here we unravel the mechanisms by which AP-1 enables the maintenance of RCs’ anchoring to the PM during size expansion. We show that AP-1 regulates the localization of the intercellular adhesion molecule E-cadherin and that loss of AP-1 causes the disappearance of the E-cadherin–containing adhesive clusters surrounding the RCs. E-cadherin itself is shown to be required for the maintenance of the RCs’ anchorage, a function previously unrecognized because of functional compensation by N-cadherin. Scanning block-face EM combined with transmission EM analyses reveals the presence of interdigitated, actin- and Moesin-positive, microvilli-like structures wrapping the RCs. Thus, by modulating E-cadherin trafficking, we show that the sustained E-cadherin–dependent adhesion organizes the microvilli meshwork and ensures the proper attachment of RCs to the PM, thereby counteracting the increasing membrane tension induced by exponential tissue growth. PMID:26424451

  2. A distinct profile of serum levels of soluble intercellular adhesion molecule-1 and intercellular adhesion molecule-3 in mycosis fungoides and Sézary syndrome.

    PubMed

    López-Lerma, Ingrid; Estrach, Maria Teresa

    2009-08-01

    Cell adhesion molecules (CAMs) play a pivotal role in cutaneous localization of T cells. Tissue-selective localization of T lymphocytes to the skin is crucial for immune surveillance and in the pathogenesis of skin disorders. To detect the profile of soluble CAMs in patients with cutaneous T-cell lymphoma (CTCL), we investigated the levels of intercellular adhesion molecule-1 (ICAM-1, soluble ICAM-1 [sICAM-1]); intercellular adhesion molecule-3 (sICAM-3); vascular cell adhesion molecule-1 (sVCAM-1); and E-selectin (sE-selectin) in sera from patients with T-cell-mediated skin diseases. Serum levels of the 4 CAMs were measured by enzyme-linked immunosorbent assay in 42 participants including 11 patients with early stages of CTCL; 7 with advanced stages of CTCL including Sézary syndrome; 12 with inflammatory skin diseases (psoriasis and atopic dermatitis); 8 with skin diseases that may evolve into CTCL; and healthy individuals. Levels were correlated with biological parameters known as prognostic factors in non-Hodgkin lymphomas. In patients with CTCL, significantly increased levels of sICAM-1 and sICAM-3 were found when compared with healthy individuals and patients with inflammatory dermatosis. Soluble E-selectin and sVCAM-1 levels were not increased. There were significant positive correlations between sICAM-1 and sICAM-3 levels and each of them with beta2-microglobulin levels. Limited number of patients was a limitation. There is a distinct profile of soluble CAMs in patients with CTCL. However, future studies with a larger group of patients are needed to confirm these findings. We propose that high sICAM-1 and sICAM-3 levels have important implications in the context of immune response and immune surveillance in these patients.

  3. Single and collective cell migration: the mechanics of adhesions

    PubMed Central

    De Pascalis, Chiara; Etienne-Manneville, Sandrine

    2017-01-01

    Chemical and physical properties of the environment control cell proliferation, differentiation, or apoptosis in the long term. However, to be able to move and migrate through a complex three-dimensional environment, cells must quickly adapt in the short term to the physical properties of their surroundings. Interactions with the extracellular matrix (ECM) occur through focal adhesions or hemidesmosomes via the engagement of integrins with fibrillar ECM proteins. Cells also interact with their neighbors, and this involves various types of intercellular adhesive structures such as tight junctions, cadherin-based adherens junctions, and desmosomes. Mechanobiology studies have shown that cell–ECM and cell–cell adhesions participate in mechanosensing to transduce mechanical cues into biochemical signals and conversely are responsible for the transmission of intracellular forces to the extracellular environment. As they migrate, cells use these adhesive structures to probe their surroundings, adapt their mechanical properties, and exert the appropriate forces required for their movements. The focus of this review is to give an overview of recent developments showing the bidirectional relationship between the physical properties of the environment and the cell mechanical responses during single and collective cell migration. PMID:28684609

  4. Intercellular adhesion molecule-1 augments myoblast adhesion and fusion through homophilic trans-interactions.

    PubMed

    Pizza, Francis X; Martin, Ryan A; Springer, Evan M; Leffler, Maxwell S; Woelmer, Bryce R; Recker, Isaac J; Leaman, Douglas W

    2017-07-11

    The overall objective of the study was to identify mechanisms through which intercellular adhesion molecule-1 (ICAM-1) augments the adhesive and fusogenic properties of myogenic cells. Hypotheses were tested using cultured myoblasts and fibroblasts, which do not constitutively express ICAM-1, and myoblasts and fibroblasts forced to express full length ICAM-1 or a truncated form lacking the cytoplasmic domain of ICAM-1. ICAM-1 mediated myoblast adhesion and fusion were quantified using novel assays and cell mixing experiments. We report that ICAM-1 augments myoblast adhesion to myoblasts and myotubes through homophilic trans-interactions. Such adhesive interactions enhanced levels of active Rac in adherent and fusing myoblasts, as well as triggered lamellipodia, spreading, and fusion of myoblasts through the signaling function of the cytoplasmic domain of ICAM-1. Rac inhibition negated ICAM-1 mediated lamellipodia, spreading, and fusion of myoblasts. The fusogenic property of ICAM-1-ICAM-1 interactions was restricted to myogenic cells, as forced expression of ICAM-1 by fibroblasts did not augment their fusion to ICAM-1+ myoblasts/myotubes. We conclude that ICAM-1 augments myoblast adhesion and fusion through its ability to self-associate and initiate Rac-mediated remodeling of the actin cytoskeleton.

  5. Active properties of living tissues lead to size-dependent dewetting

    NASA Astrophysics Data System (ADS)

    Perez-Gonzalez, Carlos; Alert, Ricard; Blanch-Mercader, Carles; Gomez-Gonzalez, Manuel; Casademunt, Jaume; Trepat, Xavier

    Key biological processes such as cancer and development are characterized by drastic transitions from 2D to a 3D geometry. These rearrangements have been classically studied as a wetting problem. According to this theory, wettability of a substrate by an epithelium is determined by the competition between cell-cell and cell-substrate adhesion energies. In contrast, we found that, far from a passive process, tissue dewetting is an active process driven by tissue internal forces. Experimentally, we reproduced epithelial dewetting by promoting a progressive formation of intercellular junctions in a monolayer of epithelial cells. Interestingly, the formation of intercellular junctions produces an increase in cell contractility, with the subsequent increase in traction and intercellular stress. At a certain time, tissue tension overcomes cell-substrate maximum adhesion and the monolayer spontaneously dewets the substrate. We developed an active polar fluid model, finding both theoretically and experimentally that critical contractility to promote wetting-dewetting transition depends on cell-substrate adhesion and, unexpectedly, on tissue size. As a whole, this work generalizes wetting theory to living tissues, unveiling unprecedented properties due to their unique active nature.

  6. A nonpolio enterovirus with respiratory tropism causes poliomyelitis in intercellular adhesion molecule 1 transgenic mice.

    PubMed

    Dufresne, Andrew T; Gromeier, Matthias

    2004-09-14

    Coxsackievirus A21 (CAV21) is classified within the species Human enterovirus C (HEV-C) of the Enterovirus genus of picornaviruses. HEV-C share striking homology with the polioviruses (PV), their closest kin among the enteroviruses. Despite a high level of sequence identity, CAV21 and PV cause distinct clinical disease typically attributed to their differential use of host receptors. PV cause poliomyelitis, whereas CAV21 shares a receptor and a propensity to cause upper respiratory tract infections with the major group rhinoviruses. As a model for CAV21 infection, we have developed transgenic mice that express human intercellular adhesion molecule 1, the cell-surface receptor for CAV21. Surprisingly, CAV21 administered to these mice via the intramuscular route causes a paralytic condition consistent with poliomyelitis. The virus appears to invade the CNS by retrograde axonal transport, as has been demonstrated to occur in analogous PV infections. We detected human intercellular adhesion molecule 1 expression on both transgenic mouse and human spinal cord anterior horn motor neurons, indicating that members of HEV-C may share PV's potential to elicit poliomyelitis in humans.

  7. Allosteric Regulation of E-Cadherin Adhesion*

    PubMed Central

    Shashikanth, Nitesh; Petrova, Yuliya I.; Park, Seongjin; Chekan, Jillian; Maiden, Stephanie; Spano, Martha; Ha, Taekjip; Gumbiner, Barry M.; Leckband, Deborah E.

    2015-01-01

    Cadherins are transmembrane adhesion proteins that maintain intercellular cohesion in all tissues, and their rapid regulation is essential for organized tissue remodeling. Despite some evidence that cadherin adhesion might be allosterically regulated, testing of this has been hindered by the difficulty of quantifying altered E-cadherin binding affinity caused by perturbations outside the ectodomain binding site. Here, measured kinetics of cadherin-mediated intercellular adhesion demonstrated quantitatively that treatment with activating, anti-E-cadherin antibodies or the dephosphorylation of a cytoplasmic binding partner, p120ctn, increased the homophilic binding affinity of E-cadherin. Results obtained with Colo 205 cells, which express inactive E-cadherin and do not aggregate, demonstrated that four treatments, which induced Colo 205 aggregation and p120ctn dephosphorylation, triggered quantitatively similar increases in E-cadherin affinity. Several processes can alter cell aggregation, but these results directly demonstrated the allosteric regulation of cell surface E-cadherin by p120ctn dephosphorylation. PMID:26175155

  8. Mannosyl Glycodendritic Structure Inhibits DC-SIGN-Mediated Ebola Virus Infection in cis and in trans

    PubMed Central

    Lasala, Fátima; Arce, Eva; Otero, Joaquín R.; Rojo, Javier; Delgado, Rafael

    2003-01-01

    We have designed a glycodendritic structure, BH30sucMan, that blocks the interaction between dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN) and Ebola virus (EBOV) envelope. BH30sucMan inhibits DC-SIGN-mediated EBOV infection at nanomolar concentrations. BH30sucMan may counteract important steps of the infective process of EBOV and, potentially, of microorganisms shown to exploit DC-SIGN for cell entry and infection. PMID:14638512

  9. [Effect of Golgi α-mannosidase 2 (GM2) gene knockdown on adhesion abilities of human gastric carcinoma cell line BGC-823 and its mechanism].

    PubMed

    Zeng, Bo; Zeng, Zhen; Liu, Chang; Yang, Yaying

    2017-06-01

    Objective To investigate the effect of Golgi α-mannosidase II (GM2) gene knockdown on adhesion abilities of BGC-823 human gastric carcinoma cells. Methods Three plasmid vectors expressing GM2 shRNAs and a negative control plasmid vector were designed, constructed and then transfected into BGC-823 cells by Lipofectamine TM 2000. After transfection, the mRNA and protein levels of GM2 in BGC-823 cells were detected by real-time quantitative PCR (qRT-PCR) and Western blotting to evaluate the transfection efficacy. The best plasmid for GM2 gene knockdown was selected and stably transfected into BGC-823 cells. Adhesion abilities of BGC-823 cells after GM2 gene silencing were observed by cell-cell, cell-matrix and cell-endothelial cell adhesion assays. At the same time, the expressions of E-cadherin, P-selectin, CD44v6 and intercellular adhesion molecule-1 (ICAM-1) proteins were detected by Western blotting after GM2 gene knockdown. Results The expression of GM2 was effectively knockdown in GM2-shRNA-2-transfected BGC-823 cells. Compared with the blank control group and the negative control group, the intercellular adhesion ability of the GM2-shRNA-2-transfected cells increased significantly, while their cell-matrix and cell-endothelium adhesion abilities markedly decreased. In GM2-shRNA-2 transfection group, E-cadherin expression was significantly elevated and the P-selectin expression was significantly reduced, while the expression levels of CD44v6 and ICAM-1 were not obviously changed. Conclusion After GM2 gene knockdown, the intercellular adhesion ability of gastric carcinoma BGC-823 cells is enhanced, while the adhesion abilities with the extracellular matrix and endothelial cells are weakened. The changes might be related to the up-regulated expression of E-cadherin and the down-regulation of P-selectin.

  10. Failure of physiologic transformation of spiral arteries, endothelial and trophoblast cell activation, and acute atherosis in the basal plate of the placenta.

    PubMed

    Labarrere, Carlos A; DiCarlo, Hector L; Bammerlin, Elaine; Hardin, James W; Kim, Yeon M; Chaemsaithong, Piya; Haas, David M; Kassab, Ghassan S; Romero, Roberto

    2017-03-01

    Failure of physiologic transformation of spiral arteries has been reported in preeclampsia, fetal growth restriction, fetal death, and spontaneous preterm labor with intact or ruptured membranes. Spiral arteries with failure of physiologic transformation are prone to develop atherosclerotic-like lesions of atherosis. There are striking parallels between preeclampsia and atherosclerotic disease, and between lesions of atherosis and atherosclerosis. Endothelial activation, identified by intercellular adhesion molecule-1 expression, is present in atherosclerotic-like lesions of heart transplantation, and is considered a manifestation of rejection. Similarly, endothelial activation/dysfunction has been implicated in the pathophysiology of atherosclerosis and preeclampsia. Intercellular adhesion molecule-1-overexpressing-activated endothelial cells are more resistant to trophoblast displacement than nonactivated endothelium, and may contribute to shallow spiral artery trophoblastic invasion in obstetrical syndromes having failure of physiologic transformation. We sought to determine whether failure of spiral artery physiologic transformation was associated with activation of interstitial extravillous trophoblasts and/or spiral artery endothelium and presence of acute atherosis in the placental basal plate. A cross-sectional study of 123 placentas (19-42 weeks' gestation) obtained from normal pregnancies (n = 22), preterm prelabor rupture of membranes (n = 26), preterm labor (n = 23), preeclampsia (n = 27), intrauterine fetal death (n = 15), and small for gestational age (n = 10) was performed. Failure of spiral artery physiologic transformation and presence of cell activation was determined using immunohistochemistry of placental basal plates containing a median of 4 (minimum: 1; maximum: 9) vessels per placenta. Endothelial/trophoblast cell activation was defined by the expression of intercellular adhesion molecule-1. Investigators examining microscopic sections were blinded to clinical diagnosis. Pairwise comparisons among placenta groups were performed with Fisher exact test and Wilcoxon rank sum test using a Bonferroni-adjusted level of significance (.025). We found that 87% (94/108) of placentas having spiral arteries with failure of physiologic transformation (actin-positive and cytokeratin-negative) in the basal plate, and 0% (0/15) of placentas having only spiral arteries with complete physiologic transformation (cytokeratin-positive and actin-negative), had arterial endothelial and/or interstitial extravillous trophoblasts reactive with the intercellular adhesion molecule-1 activation marker (P < .001). A significant correlation (R 2  = 0.84) was found between expression of spiral artery endothelial and interstitial extravillous trophoblast intercellular adhesion molecule-1 (P < .001) in activated placentas. Lesions of atherosis were found in 31.9% (30/94) of placentas with complete and/or partial failure of physiologic transformation of spiral arteries that were intercellular adhesion molecule-1-positive, in none of the 14 placentas with failure of physiologic transformation that were intercellular adhesion molecule-1-negative, and in none of the 15 placentas with complete spiral artery physiologic transformation without failure (P = .001). All placentas (30/30, 100%) with atherosis were identified in placentas having concomitant spiral artery endothelial and interstitial extravillous trophoblast activation. Failure of spiral artery physiologic transformation in the placental basal plate is associated with interstitial extravillous trophoblast and arterial endothelial activation along with increased frequency of spiral artery atherosis. These findings may be used to improve the characterization of different disorders of the placental bed such as in refining the existing tools for the early prediction of risk for preterm, preeclamptic, and other abnormal pregnancies. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Cell adhesion molecules, the extracellular matrix and oral squamous carcinoma.

    PubMed

    Lyons, A J; Jones, J

    2007-08-01

    Carcinomas are characterized by invasion of malignant cells into the underlying connective tissue and migration of malignant cells to form metastases at distant sites. These processes require alterations in cell-cell and cell-extracellular matrix interactions. As cell adhesion molecules play a role in cell-cell and cell-extracellular matrix adhesion and interactions they are involved in the process of tumour invasion and metastases. In epithelial tissues, receptors of the integrin family mediate adhesion to the adjacent matrix whereas cadherins largely mediate intercellular adhesion. These and other cell adhesion molecules such as intercellular adhesion molecule-1, CD44, dystroglycans and selectins, are involved and undergo changes in carcinomas, which provide possible targets for anti-cancer drug treatments. In the extracellular matrix that is associated with tumours, laminin 5, oncofetal fibronectin and tenascin C appear. The degree of expression of some of these moieties indicates prognosis in oral cancer and offer targets for antibody-directed radiotherapy. Metalloproteases which degrade the extracellular matrix are increased in carcinomas, and their activity is necessary for tumour angiogenesis and consequent invasion and metastases. Metalloprotease inhibitors have begun to produce decreases in mortality in clinical trials. This report provides a brief overview of our current understanding of cell adhesion molecules, the extracellular matrix, tumour invasion and metastasis.

  12. New insights into desmosome regulation and pemphigus blistering as a desmosome-remodeling disease.

    PubMed

    Kitajima, Yasuo

    2013-01-01

    Desmosomes in keratinocytes are the most important intercellular adhering junctions that provide structural strength for the epidermis. These junctions are connected directly with desmosomal cadherin proteins. Desmosomal cadherins are divided into four desmogleins (Dsgs), Dsg1-4, and three desmocollins (Dscs), Dsc1-3, all of which are involved in desmosomal adhesion by homo- and/or heterophilic binding between Dsgs and Dscs in a Ca(2+)-dependent manner. Cadherins are present on the cell surface and anchor keratin intermediate filaments (KIFs) to their inner cytoplasmic surface to generate an intracellular KIF-skeletal scaffold through several associate proteins, including plakoglobin, plakophillin, and desmoplakins. As such, the desmosomal contacts between adjacent cells generate an intercellular KIF scaffold throughout the whole epidermal sheet. However, despite these critical roles in maintaining epidermal adhesion and integrity, desmosomes are not static structures. Rather, they are dynamic units that undergo regular remodeling, i.e., assembly and disassembly, to allow for cell migration within the epidermis in response to outside-in signaling during epidermal differentiation. Recently, two cell-cell adhesion states controlled by desmosomes have been recognized, including "stable hyperadhesion (Ca(2+)-independent)" and "dynamic weak-adhesion (Ca(2+)-dependent)" conditions. These conditions are mutually reversible through cell signaling events involving protein kinase C (PKC) and epidermal growth factor receptor. Pemphigus vulgaris (PV) is an autoimmune bullous disease caused by anti-Dsg3 antibodies. Binding of these antibodies to Dsg3 causes endocytosis of Dsg3 from the cell surface and results in the specific depletion of Dsg3 from desmosomes, an event linked to acantholysis in the epidermis. This binding of anti-Dsg3 antibody to Dsg3 in epidermal keratinocytes activates PKC, to generate the "weak-adhesion (Ca(2+)-dependent)" state of desmosomes. The weak-adhesion desmosomes appear to be the susceptible desmosomal state and a prerequisite for Dsg3 depletion from desmosomes, pivotal and specific events leading to PV blistering. These observations allow us to propose a concept for pemphigus blistering disorders as a "desmosome-remodeling impairment disease" involving a mechanism of Dsg3 nonassembly and depletion from desmosomes through PV immunoglobulin G-activated intracellular signaling events. Copyright © 2012. Published by Elsevier B.V.

  13. 14-3-3 proteins regulate desmosomal adhesion via plakophilins.

    PubMed

    Rietscher, Katrin; Keil, René; Jordan, Annemarie; Hatzfeld, Mechthild

    2018-05-22

    Desmosomes are essential for strong intercellular adhesion and are abundant in tissues exposed to mechanical strain. At the same time, desmosomes need to be dynamic to allow for remodeling of epithelia during differentiation or wound healing. Phosphorylation of desmosomal plaque proteins appears to be essential for desmosome dynamics. However, the mechanisms of how context-dependent post-translational modifications regulate desmosome formation, dynamics or stability are incompletely understood. Here, we show that growth factor signaling regulates the phosphorylation-dependent association of plakophilins 1 and 3 (PKP1 and PKP3) with 14-3-3 protein isoforms, and uncover unique and partially antagonistic functions of members of the 14-3-3 family in the regulation of desmosomes. 14-3-3γ associated primarily with cytoplasmic PKP1 phosphorylated at S155 and destabilized intercellular cohesion of keratinocytes by reducing its incorporation into desmosomes. In contrast, 14-3-3σ (also known as stratifin, encoded by SFN ) interacted preferentially with S285-phosphorylated PKP3 to promote its accumulation at tricellular contact sites, leading to stable desmosomes. Taken together, our study identifies a new layer of regulation of intercellular adhesion by 14-3-3 proteins. © 2018. Published by The Company of Biologists Ltd.

  14. Holding Tight: Cell Junctions and Cancer Spread.

    PubMed

    Knights, Alexander J; Funnell, Alister P W; Crossley, Merlin; Pearson, Richard C M

    2012-01-01

    Cell junctions are sites of intercellular adhesion that maintain the integrity of epithelial tissue and regulate signalling between cells. These adhesive junctions are comprised of protein complexes that serve to establish an intercellular cytoskeletal network for anchoring cells, in addition to regulating cell polarity, molecular transport and communication. The expression of cell adhesion molecules is tightly controlled and their downregulation is essential for epithelial-mesenchymal transition (EMT), a process that facilitates the generation of morphologically and functionally diverse cell types during embryogenesis. The characteristics of EMT are a loss of cell adhesion and increased cellular mobility. Hence, in addition to its normal role in development, dysregulated EMT has been linked to cancer progression and metastasis, the process whereby primary tumors migrate to invasive secondary sites in the body. This paper will review the current understanding of cell junctions and their role in cancer, with reference to the abnormal regulation of junction protein genes. The potential use of cell junction molecules as diagnostic and prognostic markers will also be discussed, as well as possible therapies for adhesive dysregulation.

  15. Allosteric Regulation of E-Cadherin Adhesion.

    PubMed

    Shashikanth, Nitesh; Petrova, Yuliya I; Park, Seongjin; Chekan, Jillian; Maiden, Stephanie; Spano, Martha; Ha, Taekjip; Gumbiner, Barry M; Leckband, Deborah E

    2015-08-28

    Cadherins are transmembrane adhesion proteins that maintain intercellular cohesion in all tissues, and their rapid regulation is essential for organized tissue remodeling. Despite some evidence that cadherin adhesion might be allosterically regulated, testing of this has been hindered by the difficulty of quantifying altered E-cadherin binding affinity caused by perturbations outside the ectodomain binding site. Here, measured kinetics of cadherin-mediated intercellular adhesion demonstrated quantitatively that treatment with activating, anti-E-cadherin antibodies or the dephosphorylation of a cytoplasmic binding partner, p120(ctn), increased the homophilic binding affinity of E-cadherin. Results obtained with Colo 205 cells, which express inactive E-cadherin and do not aggregate, demonstrated that four treatments, which induced Colo 205 aggregation and p120(ctn) dephosphorylation, triggered quantitatively similar increases in E-cadherin affinity. Several processes can alter cell aggregation, but these results directly demonstrated the allosteric regulation of cell surface E-cadherin by p120(ctn) dephosphorylation. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Occludin confers adhesiveness when expressed in fibroblasts.

    PubMed

    Van Itallie, C M; Anderson, J M

    1997-05-01

    Occludin is an integral membrane protein specifically associated with tight junctions. Previous studies suggest it is likely to function in forming the intercellular seal. In the present study, we expressed occludin under an inducible promotor in occludin-null fibroblasts to determine whether this protein confers intercellular adhesion. When human occludin is stably expressed in NRK and Rat-1 fibroblasts, which lack endogenous occludin and tight junctions but do have well developed ZO-1-containing adherens-like junctions, occludin colocalizes with ZO-1 to points of cell-cell contact. In contrast, L-cell fibroblasts which lack cadherin-based adherens junctions, target neither ZO-1 nor occludin to sites of cell contact. Occludin-induced adhesion was next quantified using a suspended cell assay. In NRK and Rat-1 cells, occludin expression induces adhesion in the absence of calcium, thus independent of cadherin-cadherin contacts. In contrast, L-cells are nonadhesive in this assay and show no increase in adhesion after induction of occludin expression. Binding of an antibody to the first of the putative extracellular loops of occludin confirmed that this sequence was exposed on the cell surface, and synthetic peptides containing the amino acid sequence of this loop inhibit adhesion induced by occludin expression. These results suggest that the extracellular surface of occludin is directly involved in cell-cell adhesion and the ability to confer adhesiveness correlates with the ability to colocalize with its cytoplasmic binding protein, ZO-1.

  17. Glucocorticoid-induced tumor necrosis factor receptor family-related ligand triggering upregulates vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 and promotes leukocyte adhesion.

    PubMed

    Lacal, Pedro Miguel; Petrillo, Maria Grazia; Ruffini, Federica; Muzi, Alessia; Bianchini, Rodolfo; Ronchetti, Simona; Migliorati, Graziella; Riccardi, Carlo; Graziani, Grazia; Nocentini, Giuseppe

    2013-10-01

    The interaction of glucocorticoid-induced tumor necrosis factor receptor-family related (GITR) protein with its ligand (GITRL) modulates different functions, including immune/inflammatory response. These effects are consequent to intracellular signals activated by both GITR and GITRL. Previous results have suggested that lack of GITR expression in GITR(-/-) mice decreases the number of leukocytes within inflamed tissues. We performed experiments to analyze whether the GITRL/GITR system modulates leukocyte adhesion and extravasation. For that purpose, we first evaluated the capability of murine splenocytes to adhere to endothelial cells (EC). Our results indicated that adhesion of GITR(-/-) splenocytes to EC was reduced as compared with wild-type cells, suggesting that GITR plays a role in adhesion and that this effect may be due to GITRL-GITR interaction. Moreover, adhesion was increased when EC were pretreated with an agonist GITR-Fc fusion protein, thus indicating that triggering of GITRL plays a role in adhesion by EC regulation. In a human in vitro model, the adhesion to human EC of HL-60 cells differentiated toward the monocytic lineage was increased by EC pretreatment with agonist GITR-Fc. Conversely, antagonistic anti-GITR and anti-GITRL Ab decreased adhesion, thus further indicating that GITRL triggering increases the EC capability to support leukocyte adhesion. EC treatment with GITR-Fc favored extravasation, as demonstrated by a transmigration assay. Notably, GITRL triggering increased intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expression and anti-ICAM-1 and anti-VCAM-1 Abs reversed GITR-Fc effects. Our study demonstrates that GITRL triggering in EC increases leukocyte adhesion and transmigration, suggesting new anti-inflammatory therapeutic approaches based on inhibition of GITRL-GITR interaction.

  18. β-Catenin Serves as a Clutch between Low and High Intercellular E-Cadherin Bond Strengths

    PubMed Central

    Bajpai, Saumendra; Feng, Yunfeng; Wirtz, Denis; Longmore, Gregory D.

    2013-01-01

    A wide range of invasive pathological outcomes originate from the loss of epithelial phenotype and involve either loss of function or downregulation of transmembrane adhesive receptor complexes, including Ecadherin (Ecad) and binding partners β-catenin and α-catenin at adherens junctions. Cellular pathways regulating wild-type β-catenin level, or direct mutations in β-catenin that affect the turnover of the protein have been shown to contribute to cancer development, through induction of uncontrolled proliferation of transformed tumor cells, particularly in colon cancer. Using single-molecule force spectroscopy, we show that depletion of β-catenin or the prominent cancer-related S45 deletion mutation in β-catenin present in human colon cancers both weaken tumor intercellular Ecad/Ecad bond strength and diminishes the capacity of specific extracellular matrix proteins—including collagen I, collagen IV, and laminin V—to modulate intercellular Ecad/Ecad bond strength through α-catenin and the kinase activity of glycogen synthase kinase 3 (GSK-3β). Thus, in addition to regulating tumor cell proliferation, cancer-related mutations in β-catenin can influence tumor progression by weakening the adhesion of tumor cells to one another through reduced individual Ecad/Ecad bond strength and cellular adhesion to specific components of the extracellular matrix and the basement membrane. PMID:24268141

  19. Neutrophil adherence to isolated adult canine myocytes. Evidence for a CD18-dependent mechanism.

    PubMed

    Entman, M L; Youker, K; Shappell, S B; Siegel, C; Rothlein, R; Dreyer, W J; Schmalstieg, F C; Smith, C W

    1990-05-01

    Cardiac myocytes were isolated from adult dogs and incubated with isolated canine neutrophils (PMN). Intercellular adhesion was low and unchanged by stimulation of the PMN with zymosan activated serum or platelet activating factor (PAF) at concentrations that significantly enhance PMN adhesion to protein-coated glass and canine endothelial cell monolayers. Intercellular adhesion was significantly increased only when both myocytes and PMN were stimulated (e.g., myocytes incubated with IL-1, tumor necrosis factor, or phorbol myristate acetate, and PMN were chemotactically stimulated). Inhibitors of protein synthesis diminished the IL-1 beta-induced effect by greater than 80%. The IL-1 beta, PAF-stimulated PMN-myocyte adhesion was associated with substantial H2O2 production. Under conditions with low PMN-myocyte adhesion (i.e., IL-1 beta alone, PAF alone, or no stimulus) H2O2 production was generally less than 5% of that occurring with high adhesion. An anti-CD18 monoclonal antibody (R15.7) inhibited stimulated PMN-myocyte adhesion by greater than 95% and reduced H2O2 production by greater than 90%. Control isotype-matched, binding, and nonbinding antibodies were without effect on adherence or H2O2 production. The results indicate that cytokine stimulation of adult myocytes induces expression of a ligand involved in CD18-dependent adherence of canine neutrophils.

  20. Effects of lead intoxication on intercellular junctions and biochemical alterations of the renal proximal tubule cells.

    PubMed

    Navarro-Moreno, L G; Quintanar-Escorza, M A; González, S; Mondragón, R; Cerbón-Solorzáno, J; Valdés, J; Calderón-Salinas, J V

    2009-10-01

    Lead intoxication is a worldwide health problem which frequently affects the kidney. In this work, we studied the effects of chronic lead intoxication (500 ppm of Pb in drinking water during seven months) on the structure, function and biochemical properties of rat proximal tubule cells. Lead-exposed animals showed increased lead concentration in kidney, reduction of calcium and amino acids uptake, oxidative damage and glucosuria, proteinuria, hematuria and reduced urinary pH. These biochemical and physiological alterations were related to striking morphological modifications in the structure of tubule epithelial cells and in the morphology of their mitochondria, nuclei, lysosomes, basal and apical membranes. Interestingly, in addition to the nuclei, inclusion bodies were found in the cytoplasm and in mitochondria. The epithelial cell structure modifications included an early loss of the apical microvillae, followed by a decrement of the luminal space and the respective apposition and proximity of apical membranes, resulting in the formation of atypical intercellular contacts and adhesion structures. Similar but less marked alterations were observed in subacute lead intoxication as well. Our work contributes in the understanding of the physiopathology of lead intoxication on the structure of renal tubular epithelial cell-cell contacts in vivo.

  1. Reduced endothelial activation after exercise is associated with improved HbA1c in patients with type 2 diabetes and coronary artery disease.

    PubMed

    Byrkjeland, Rune; Njerve, Ida U; Arnesen, Harald; Seljeflot, Ingebjørg; Solheim, Svein

    2017-03-01

    We have previously reported insignificant changes in HbA 1c after exercise in patients with both type 2 diabetes and coronary artery disease. In this study, we investigated the effect of exercise on endothelial function and possible associations between changes in endothelial function and HbA 1c . Patients with type 2 diabetes and coronary artery disease ( n = 137) were randomised to 12 months exercise or standard follow-up. Endothelial function was assessed by circulating biomarkers (E-selectin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, von Willebrand factor, tissue plasminogen activator antigen, asymmetric dimethylarginine and L-arginine/asymmetric dimethylarginine ratio). Differences between the randomised groups were analysed by analysis of covariance and correlations by Spearman's rho or Pearson's correlation. No effect of exercise on endothelial function was demonstrated. The changes in HbA 1c in the exercise group correlated with changes in E-selectin ( r = 0.56, p < 0.001), intercellular adhesion molecule-1 ( r = 0.27, p = 0.052), vascular cell adhesion molecule-1 ( r = 0.32, p = 0.022) and tissue plasminogen activator antigen ( r = 0.35, p =  0.011). HbA 1c decreased significantly more in patients with versus without a concomitant reduction in E-selectin ( p =  0.002), intercellular adhesion molecule-1 ( p =  0.011), vascular cell adhesion molecule-1 ( p =  0.028) and tissue plasminogen activator antigen ( p =  0.009). Exercise did not affect biomarkers of endothelial function in patients with both type 2 diabetes and coronary artery disease. However, changes in biomarkers of endothelial activation correlated with changes in HbA 1c , and reduced endothelial activation was associated with improved HbA 1c after exercise.

  2. De-adhesion dynamics of melanoma cells from brain endothelial layer.

    PubMed

    Varga, Béla; Domokos, Réka Anita; Fazakas, Csilla; Wilhelm, Imola; Krizbai, István A; Szegletes, Zsolt; Gergely, Csilla; Váró, György; Végh, Attila G

    2018-03-01

    Metastasis formation is a complex and not entirely understood process. The poorest prognosis and the most feared complications are associated to brain metastases. Melanoma derived brain metastases show the highest prevalence. Due to the lack of classical lymphatic drainage, in the process of brain metastases formation the haematogenous route is of primordial importance. The first and crucial step in this multistep process is the establishment of firm adhesion between the blood travelling melanoma cells and the tightly connected layer of the endothelium, which is the fundamental structure of the blood-brain barrier. This study compares the de-adhesion properties and dynamics of three melanoma cells types (WM35, A2058 and A375) to a confluent layer of brain micro-capillary endothelial cells. Cell type dependent adhesion characteristics are presented, pointing towards the existence of metastatic potential related nanomechanical aspects. Apparent mechanical properties such as elasticity, maximal adhesion force, number, size and distance of individual rupture events showed altered values pointing towards cell type dependent aspects. Our results underline the importance of mechanical details in case of intercellular interactions. Nevertheless, it suggests that in adequate circumstances elastic and adhesive characterizations might be used as biomarkers. Copyright © 2017. Published by Elsevier B.V.

  3. Medium-chain, triglyceride-containing lipid emulsions increase human neutrophil beta2 integrin expression, adhesion, and degranulation.

    PubMed

    Wanten, G J; Geijtenbeek, T B; Raymakers, R A; van Kooyk, Y; Roos, D; Jansen, J B; Naber, A H

    2000-01-01

    To test the hypothesis that lipid emulsions with different triglyceride structures have distinct immunomodulatory properties, we analyzed human neutrophil adhesion and degranulation after lipid incubation. Neutrophils, isolated from the blood of 10 healthy volunteers, were incubated in medium or physiologic (2.5 mmol/L) emulsions containing long-chain (LCT), medium-chain (MCT), mixed LCT/MCT, or structured (SL) triglycerides. Expression of adhesion molecules and degranulation markers was evaluated by flow cytometry. Also, functional adhesion was investigated by means of a flow cytometric assay using fluorescent beads coated with the integrin ligand intercellular adhesion molecule (ICAM)-1. Although LCT and SL had no effect, LCT/MCT significantly increased expression of the beta2 integrins lymphocyte-function-associated antigen 1 (+18%), macrophage antigen 1 (+387%), p150,95 (+82%), and (alphaDbeta2 (+230%). Degranulation marker expression for azurophilic (CD63, +210%) and specific granules (CD66b, +370%) also significantly increased, whereas L-selectin (CD62L, -70%) decreased. The effects of LCT/MCT were mimicked by the MCT emulsion. ICAM-1 adhesion (% beads bound) was increased by LCT/MCT (34% +/- 4%), whereas LCT (19% +/-3%) and SL (20% +/- 2%) had no effect compared with medium (17% +/- 3%). LCT/MCT and MCT, contrary to LCT and SL emulsions, increased neutrophil beta2 integrin expression, adhesion, and degranulation. Apart from other emulsion constituents, triglyceride chain length might therefore be a key feature in the interaction of lipid emulsions and the phagocyte immune system.

  4. Induction of Cell Scattering by Expression of β1 Integrins in β1-Deficient Epithelial Cells Requires Activation of Members of the Rho Family of Gtpases and Downregulation of Cadherin and Catenin Function

    PubMed Central

    Gimond, Clotilde; van der Flier, Arjan; van Delft, Sanne; Brakebusch, Cord; Kuikman, Ingrid; Collard, John G.; Fässler, Reinhard; Sonnenberg, Arnoud

    1999-01-01

    Adhesion receptors, which connect cells to each other and to the surrounding extracellular matrix (ECM), play a crucial role in the control of tissue structure and of morphogenesis. In this work, we have studied how intercellular adhesion molecules and β1 integrins influence each other using two different β1-null cell lines, epithelial GE11 and fibroblast-like GD25 cells. Expression of β1A or the cytoplasmic splice variant β1D, induced the disruption of intercellular adherens junctions and cell scattering in both GE11 and GD25 cells. In GE11 cells, the morphological change correlated with the redistribution of zonula occluden (ZO)-1 from tight junctions to adherens junctions at high cell confluency. In addition, the expression of β1 integrins caused a dramatic reorganization of the actin cytoskeleton and of focal contacts. Interaction of β1 integrins with their respective ligands was required for a complete morphological transition towards the spindle-shaped fibroblast-like phenotype. The expression of an interleukin-2 receptor (IL2R)-β1A chimera and its incorporation into focal adhesions also induced the disruption of cadherin-based adhesions and the reorganization of ECM–cell contacts, but failed to promote cell migration on fibronectin, in contrast to full-length β1A. This indicates that the disruption of cell–cell adhesion is not simply the consequence of the stimulated cell migration. Expression of β1 integrins in GE11 cells resulted in a decrease in cadherin and α-catenin protein levels accompanied by their redistribution from the cytoskeleton-associated fraction to the detergent-soluble fraction. Regulation of α-catenin protein levels by β1 integrins is likely to play a role in the morphological transition, since overexpression of α-catenin in GE11 cells before β1 prevented the disruption of intercellular adhesions and cell scattering. In addition, using biochemical activity assays for Rho-like GTPases, we show that the expression of β1A, β1D, or IL2R-β1A in GE11 or GD25 cells triggers activation of both RhoA and Rac1, but not of Cdc42. Moreover, dominant negative Rac1 (N17Rac1) inhibited the disruption of cell–cell adhesions when expressed before β1. However, all three GTPases might be involved in the morphological transition, since expression of either N19RhoA, N17Rac1, or N17Cdc42 reversed cell scattering and partially restored cadherin-based adhesions in GE11-β1A cells. Our results indicate that β1 integrins regulate the polarity and motility of epithelial cells by the induction of intracellular molecular events involving a downregulation of α-catenin function and the activation of the Rho-like G proteins Rac1 and RhoA. PMID:10601344

  5. Application of encoded library technology (ELT) to a protein-protein interaction target: discovery of a potent class of integrin lymphocyte function-associated antigen 1 (LFA-1) antagonists.

    PubMed

    Kollmann, Christopher S; Bai, Xiaopeng; Tsai, Ching-Hsuan; Yang, Hongfang; Lind, Kenneth E; Skinner, Steven R; Zhu, Zhengrong; Israel, David I; Cuozzo, John W; Morgan, Barry A; Yuki, Koichi; Xie, Can; Springer, Timothy A; Shimaoka, Motomu; Evindar, Ghotas

    2014-04-01

    The inhibition of protein-protein interactions remains a challenge for traditional small molecule drug discovery. Here we describe the use of DNA-encoded library technology for the discovery of small molecules that are potent inhibitors of the interaction between lymphocyte function-associated antigen 1 and its ligand intercellular adhesion molecule 1. A DNA-encoded library with a potential complexity of 4.1 billion compounds was exposed to the I-domain of the target protein and the bound ligands were affinity selected, yielding an enriched small-molecule hit family. Compounds representing this family were synthesized without their DNA encoding moiety and found to inhibit the lymphocyte function-associated antigen 1/intercellular adhesion molecule-1 interaction with submicromolar potency in both ELISA and cell adhesion assays. Re-synthesized compounds conjugated to DNA or a fluorophore were demonstrated to bind to cells expressing the target protein. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Intercellular adhesion molecule-1 expression by skeletal muscle cells augments myogenesis.

    PubMed

    Goh, Qingnian; Dearth, Christopher L; Corbett, Jacob T; Pierre, Philippe; Chadee, Deborah N; Pizza, Francis X

    2015-02-15

    We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast-myoblast adhesion, myotube formation, myonuclear number, myotube alignment, myotube-myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube-myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Intercellular Adhesion Molecule-1 Expression by Skeletal Muscle Cells Augments Myogenesis

    PubMed Central

    Goh, Qingnian; Dearth, Christopher L.; Corbett, Jacob T.; Pierre, Philippe; Chadee, Deborah N.; Pizza, Francis X.

    2014-01-01

    We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast-myoblast adhesion, myotube formation, myonuclear number, myotube alignment, myotube-myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube-myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. PMID:25281303

  8. β-Catenin serves as a clutch between low and high intercellular E-cadherin bond strengths.

    PubMed

    Bajpai, Saumendra; Feng, Yunfeng; Wirtz, Denis; Longmore, Gregory D

    2013-11-19

    A wide range of invasive pathological outcomes originate from the loss of epithelial phenotype and involve either loss of function or downregulation of transmembrane adhesive receptor complexes, including Ecadherin (Ecad) and binding partners β-catenin and α-catenin at adherens junctions. Cellular pathways regulating wild-type β-catenin level, or direct mutations in β-catenin that affect the turnover of the protein have been shown to contribute to cancer development, through induction of uncontrolled proliferation of transformed tumor cells, particularly in colon cancer. Using single-molecule force spectroscopy, we show that depletion of β-catenin or the prominent cancer-related S45 deletion mutation in β-catenin present in human colon cancers both weaken tumor intercellular Ecad/Ecad bond strength and diminishes the capacity of specific extracellular matrix proteins-including collagen I, collagen IV, and laminin V-to modulate intercellular Ecad/Ecad bond strength through α-catenin and the kinase activity of glycogen synthase kinase 3 (GSK-3β). Thus, in addition to regulating tumor cell proliferation, cancer-related mutations in β-catenin can influence tumor progression by weakening the adhesion of tumor cells to one another through reduced individual Ecad/Ecad bond strength and cellular adhesion to specific components of the extracellular matrix and the basement membrane. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  9. Biomarker-guided screening of Juzen-taiho-to, an oriental herbal formulation for immunostimulation.

    PubMed

    Takaoka, Anna; Iacovidou, Maria; Hasson, Tal H; Montenegro, Diego; Li, Xiangming; Tsuji, Moriya; Kawamura, Akira

    2014-03-01

    Juzen-taiho-to is an immunostimulatory herbal formulation that is clinically used in East Asia for cancer patients undergoing chemotherapy and radiation. The formulation stimulates various leukocytes, including T, B, and NK cells and macrophages. Although Juzen-taiho-to is known to contain numerous compounds with various pharmacological activities, it is not clear which compounds are responsible for the stimulation of individual cell types. Here, we conducted what we call "biomarker-guided screening" to purify compounds responsible for the macrophages stimulatory activity. To this end, gene expression was analyzed by a DNA array for macrophages treated with Juzen-taiho-to and DMSO (vehicle control), which identified intercellular adhesion molecule 1 as a biomarker of macrophage stimulation by Juzen-taiho-to. A quantitative reverse transcription polymerase chain reaction assay of intercellular adhesion molecule 1 was then used to guide the purification of active compounds. The screening resulted in the purification of a glycolipid mixture, containing β-glucosylceramides. The glycolipid mixture potently stimulated intercellular adhesion molecule 1 expression in primary dendritic cells as well as in primary CD14+ (macrophages) cells. The identification of this glycolipid mixture opens up an opportunity for further studies to understand how plant-derived glycolipids stimulate macrophages and dendritic cells in a safe and effective manner as demonstrated by Juzen-taiho-to. Georg Thieme Verlag KG Stuttgart · New York.

  10. Twist1-positive epithelial cells retain adhesive and proliferative capacity throughout dissemination

    PubMed Central

    Shamir, Eliah R.; Coutinho, Kester; Georgess, Dan; Auer, Manfred

    2016-01-01

    ABSTRACT Dissemination is the process by which cells detach and migrate away from a multicellular tissue. The epithelial-to-mesenchymal transition (EMT) conceptualizes dissemination in a stepwise fashion, with downregulation of E-cadherin leading to loss of intercellular junctions, induction of motility, and then escape from the epithelium. This gain of migratory activity is proposed to be mutually exclusive with proliferation. We previously developed a dissemination assay based on inducible expression of the transcription factor Twist1 and here utilize it to characterize the timing and dynamics of intercellular adhesion, proliferation and migration during dissemination. Surprisingly, Twist1+ epithelium displayed extensive intercellular junctions, and Twist1– luminal epithelial cells could still adhere to disseminating Twist1+ cells. Although proteolysis and proliferation were both observed throughout dissemination, neither was absolutely required. Finally, Twist1+ cells exhibited a hybrid migration mode; their morphology and nuclear deformation were characteristic of amoeboid cells, whereas their dynamic protrusive activity, pericellular proteolysis and migration speeds were more typical of mesenchymal cells. Our data reveal that epithelial cells can disseminate while retaining competence to adhere and proliferate. PMID:27402962

  11. Levels of soluble vascular cell adhesion molecule-1 and soluble intercellular adhesion molecule-2 in plasma of patients with hemorrhagic fever with renal syndrome, and significance of the changes in level.

    PubMed

    Qi, Bao-Tai; Wang, Ping; Li, Jie; Ren, Hui-Xun; Xie, Ming

    2006-01-01

    Hemorrhagic fever with renal syndrome (HFRS) is an acute viral disease characterized by endothelial dysfunction. Vascular cell adhesion molecule (VCAM)-1 and intercellular adhesion molecule (ICAM)-2 provide costimulatory signals for the activation of T lymphocytes; these adhesion molecules play key roles in leukocyte adherence and propagation of inflammatory responses. They may be involved in the immunologic response that leads to vascular endothelial cell (VEC) and kidney damage of HFRS patients, and increased levels of soluble (s)VCAM-1 and sICAM-2 in plasma may indicate the severity of HFRS. We examined the presence of sVCAM-1 and sICAM-2 in 52 plasma samples collected from 52 patients. We tested these plasma samples for sVCAM-1 and sICAM-2 by double-antibody sandwich ELISA. We found variable, but persistently elevated, levels of sVCAM-1 and sICAM-2 throughout the various phases and types of the disease, which suggested sVCAM-1 may play an important role in the immunopathological lesions of HFRS and is closely correlated to the severity of HFRS and the degree of kidney damage. sICAM-2 may be associated with the hyperfunctioning of the cellular immune response.

  12. Structural basis of host recognition and biofilm formation by Salmonella Saf pili

    PubMed Central

    2017-01-01

    Pili are critical in host recognition, colonization and biofilm formation during bacterial infection. Here, we report the crystal structures of SafD-dsc and SafD-SafA-SafA (SafDAA-dsc) in Saf pili. Cell adherence assays show that SafD and SafA are both required for host recognition, suggesting a poly-adhesive mechanism for Saf pili. Moreover, the SafDAA-dsc structure, as well as SAXS characterization, reveals an unexpected inter-molecular oligomerization, prompting the investigation of Saf-driven self-association in biofilm formation. The bead/cell aggregation and biofilm formation assays are used to demonstrate the novel function of Saf pili. Structure-based mutants targeting the inter-molecular hydrogen bonds and complementary architecture/surfaces in SafDAA-dsc dimers significantly impaired the Saf self-association activity and biofilm formation. In summary, our results identify two novel functions of Saf pili: the poly-adhesive and self-associating activities. More importantly, Saf-Saf structures and functional characterizations help to define a pili-mediated inter-cellular oligomerizaiton mechanism for bacterial aggregation, colonization and ultimate biofilm formation. PMID:29125121

  13. Lepidotol A from Mesua lepidota Inhibits Inflammatory and Immune Mediators in Human Endothelial Cells.

    PubMed

    Rouger, Caroline; Derbré, Séverine; Charreau, Béatrice; Pabois, Angélique; Cauchy, Thomas; Litaudon, Marc; Awang, Khalijah; Richomme, Pascal

    2015-09-25

    Phytochemical investigation on the fruits of Mesua lepidota (Calophyllaceae) led to the isolation of seven new phenylcoumarin derivatives named lepidotols A-E (1-5) and lepidotins A and B (6, 7). These structures were elucidated by spectroscopic and spectrometric methods including UV, NMR, and HRMS. Lepidotol A (1), the major compound, was evaluated for its inhibitory effect on inflammation and immunity using endothelial cell-based cellular assays. At 10 μM, 1 exhibited an anti-inflammatory activity, with a significant inhibition of vascular cell adhesion molecule 1 and intercellular adhesion molecule 1 expression induced by tumor necrosis factor-α. Lepidotol A also showed a mild immunosuppressive effect, with inhibition of the major histocompatibility complex molecules, namely, human leukocyte antigen (HLA)-DR and HLA-E.

  14. Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 5: intercellular junctions and contacts between germs cells and Sertoli cells and their regulatory interactions, testicular cholesterol, and genes/proteins associated with more than one germ cell generation.

    PubMed

    Hermo, Louis; Pelletier, R-Marc; Cyr, Daniel G; Smith, Charles E

    2010-04-01

    In the testis, cell adhesion and junctional molecules permit specific interactions and intracellular communication between germ and Sertoli cells and apposed Sertoli cells. Among the many adhesion family of proteins, NCAM, nectin and nectin-like, catenins, and cadherens will be discussed, along with gap junctions between germ and Sertoli cells and the many members of the connexin family. The blood-testis barrier separates the haploid spermatids from blood borne elements. In the barrier, the intercellular junctions consist of many proteins such as occludin, tricellulin, and claudins. Changes in the expression of cell adhesion molecules are also an essential part of the mechanism that allows germ cells to move from the basal compartment of the seminiferous tubule to the adluminal compartment thus crossing the blood-testis barrier and well-defined proteins have been shown to assist in this process. Several structural components show interactions between germ cells to Sertoli cells such as the ectoplasmic specialization which are more closely related to Sertoli cells and tubulobulbar complexes that are processes of elongating spermatids embedded into Sertoli cells. Germ cells also modify several Sertoli functions and this also appears to be the case for residual bodies. Cholesterol plays a significant role during spermatogenesis and is essential for germ cell development. Lastly, we list genes/proteins that are expressed not only in any one specific generation of germ cells but across more than one generation. Copyright 2009 Wiley-Liss, Inc.

  15. [Inhibitory effect of Mig-7 silencing by retrovirus-mediated shRNA on vasculogenic mimicry, invasion and metastasis of human hepatocellular carcinoma cells in vitro].

    PubMed

    Qu, Bo; Sheng, Guan-Nan; Yu, Fei; Chen, Guan-Nan; Lv, Qi; Mao, Zhong-Peng; Guo, Long; Lv, Yi

    2016-11-20

    To explore the inhibitory effect of migration-inducing gene 7 (Mig-7) gene silencing induced by retroviral-mediated small hairpin RNA (shRNA) on vasculogenic mimicry (VM), invasion and metastasis of human hepatocellular carcinoma (HCC) cells in vitro. Two target sequences (Mig-7 shRNA-1 and Mig-7 shRNA-2) and one negative control sequence (Mig-7 shRNA-N) were synthesized. The recombinant retroviral vectors carrying Mig-7 shRNA were constructed, and HCC cell line MHCC-97H were transfected with Mig-7 shRNA-1, Mig-7 shRNA-2, Mig-7 shRNA-N, or the empty vector, or treated with 125 µg/mL recombinant human endostatin (ES). Mig-7 expression in the treated cells was detected using semi-quantitative PCR and Western blotting. The inhibitory effect of Mig-7 silencing on VM formation was investigated in a 3-dimensional cell culture system; the changes in cell adhesion, invasion and migration were assessed with intercellular adhesion assay, Transwell invasion assay and Transwell migration assay, respectively. The expression of Mig-7 at both mRNA and protein levels decreased significantly, VM formation, invasion and metastasis were suppressed, while intercellular adhesion increased significantly in MHCC-97H cells in Mig-7 shRNA-1 and Mig-7 shRNA-2 groups (P<0.05); such changes were not observed in cells transfected with Mig-7 shRNA-N or the empty vector, nor in cells treated with ES. Mig-7 silencing by retroviral-mediated shRNA significantly inhibits VM formation, invasion and metastasis and increases the intercellular adhesion of the HCC cells, while ES does not have such inhibitory effects.

  16. Interleukin-8 is associated with adhesion, migration and invasion in human gastric cancer SCG-7901 cells.

    PubMed

    Ju, Dawei; Sun, Dazhi; Xiu, Lijuan; Meng, Xianze; Zhang, Cian; Wei, Pinkang

    2012-03-01

    Interleukin-8 is known as an important chemokine involved in tumor angiogenesis and progression. Overexpression of interleukin-8 has been detected in a variety of human tumors, including gastric cancer, and is negatively correlated with prognosis. The aim of our study is to determine the effects of interleukin-8 on proliferation, adhesion, migration and invasion abilities and correlated molecular mechanisms in gastric cancer. We made recombinant interleukin-8 ranged from 0 ng/ml to 100 ng/ml interferes in human gastric cancer SCG-7901 cells in vitro. The results shown that interleukin-8 did not change cell proliferation, but promoted cell adhesion to endothelial cell and extracellular matrix components (collagen, laminin and fibronectin) as detected by Cell Counting Kit-8. And it induced migration and invasion ability based on scratch and transwell-chamber assays. Also, interleukin-8 regulated the protein and mRNA expression of matrix metalloproteinase-9, intercellular adhesion molecule-1 and E-cad and there was obviously a dose-dependent relationship, but the protein or mRNA expression of matrix metalloproteinase-2 was not obviously changed under the tested conditions. Our findings indicate that interleukin-8 is associated with adhesion, migration and invasion in gastric cancer and the regulation of matrix metalloproteinase-9, intercellular adhesion molecule-1 and E-cad expression is one of the potential molecule mechanisms. The studies imply interleukin-8 may be an alternative treatment strategy against gastric cancer.

  17. Amphiregulin enhances intercellular adhesion molecule-1 expression and promotes tumor metastasis in human osteosarcoma

    PubMed Central

    Liu, Ju-Fang; Tsao, Ya-Ting; Hou, Chun-Han

    2015-01-01

    Osteosarcoma is a common, high malignant, and metastatic bone cancer. Amphiregulin (AREG) has been associated with cancer cellular activities. However, the effect of AREG on metastasis activity in human osteosarcoma cells has yet to be determined. We determined that AREG increases the expression of intercellular adhesion molecule-1 (ICAM-1) through PI3K/Akt signaling pathway via its interaction with the epidermal growth factor receptor, thus resulting in the enhanced cell migration of osteosarcoma. Furthermore, AREG stimulation increased the association of NF-κB to ICAM-1 promoter which then up-regulated ICAM-1 expression. Finally, we observed that shRNA silencing of AREG decreased osteosarcoma metastasis in vivo. Our findings revealed a relationship between osteosarcoma metastatic potential and AREG expression and the modulating effect of AREG on ICAM-1 expression. PMID:26503469

  18. Intercellular adhesion molecule-1 blockade attenuates inflammatory response and improves microvascular perfusion in rat pancreas grafts.

    PubMed

    Preissler, Gerhard; Eichhorn, Martin; Waldner, Helmut; Winter, Hauke; Kleespies, Axel; Massberg, Steffen

    2012-10-01

    After pancreas transplantation (PTx), early capillary malperfusion and leukocyte recruitment indicate the manifestation of severe ischemia/reperfusion injury (IRI). Oscillatory blood-flow redistribution (intermittent capillary perfusion, IP), leading to an overall decrease in erythrocyte flux, precedes complete microvascular perfusion failure with persistent blood flow cessation. We addressed the role of intercellular adhesion molecule-1 (ICAM-1) for leukocyte-endothelial interactions (LEIs) after PTx and evaluated the contribution of IP and malperfusion. Pancreas transplantation was performed in rats after 18-hour preservation, receiving either isotype-matched IgG or monoclonal anti-ICAM-1 antibodies (10 mg/kg intravenously) once before reperfusion. Leukocyte-endothelial interaction, IP, erythrocyte flux, and functional capillary density, respectively, were examined in vivo during 2-hour reperfusion. Nontransplanted animals served as controls. Tissue samples were analyzed by histomorphometry. In grafts of IgG-treated animals, IP was encountered already at an early stage after reperfusion and steadily increased over 2 hours, whereas erythrocyte flux declined continuously. In contrast, inhibition of ICAM-1 significantly improved erythrocyte flux and delayed IP appearance by 2 hours. Further, anti-ICAM-1 significantly reduced LEI and leukocyte tissue infiltration when compared to IgG; edema development was less pronounced in response to anti-ICAM-1 monoclonal antibody. Intercellular adhesion molecule-1 blockade significantly attenuates IRI via immediate reduction of LEI and concomitant improvement of capillary perfusion patterns, emphasizing its central role during IRI in PTx.

  19. Mechanical entrapment is insufficient and intercellular adhesion is essential for metastatic cell arrest in distant organs.

    PubMed

    Glinskii, Olga V; Huxley, Virginia H; Glinsky, Gennadi V; Pienta, Kenneth J; Raz, Avraham; Glinsky, Vladislav V

    2005-05-01

    In this report, we challenge a common perception that tumor embolism is a size-limited event of mechanical arrest, occurring in the first capillary bed encountered by blood-borne metastatic cells. We tested the hypothesis that mechanical entrapment alone, in the absence of tumor cell adhesion to blood vessel walls, is not sufficient for metastatic cell arrest in target organ microvasculature. The in vivo metastatic deposit formation assay was used to assess the number and location of fluorescently labeled tumor cells lodged in selected organs and tissues following intravenous inoculation. We report that a significant fraction of breast and prostate cancer cells escapes arrest in a lung capillary bed and lodges successfully in other organs and tissues. Monoclonal antibodies and carbohydrate-based compounds (anti-Thomsen-Friedenreich antigen antibody, anti-galectin-3 antibody, modified citrus pectin, and lactulosyl-l-leucine), targeting specifically beta-galactoside-mediated tumor-endothelial cell adhesive interactions, inhibited by >90% the in vivo formation of breast and prostate carcinoma metastatic deposits in mouse lung and bones. Our results indicate that metastatic cell arrest in target organ microvessels is not a consequence of mechanical trapping, but is supported predominantly by intercellular adhesive interactions mediated by cancer-associated Thomsen-Friedenreich glycoantigen and beta-galactoside-binding lectin galectin-3. Efficient blocking of beta-galactoside-mediated adhesion precludes malignant cell lodging in target organs.

  20. House dust mite induces expression of intercellular adhesion molecule-1 in EoL-1 human eosinophilic leukemic cells.

    PubMed

    Kwon, Byoung Chul; Sohn, Myung Hyun; Kim, Kyung Won; Kim, Eun Soo; Kim, Kyu-Earn; Shin, Myeong Heon

    2007-10-01

    The house dust mite (HDM) is considered to be the most common indoor allergen associated with bronchial asthma. In this study, we investigated whether crude extract of the HDM Dermatophagoides farinae could activate human eosinophilic leukemic cells (EoL-1) to induce upregulation of cell-surface adhesion molecules. When EoL-1 cells were incubated with D. farinae extract, expression of intercellular adhesion molecule-1 (ICAM-1) significantly increased on the cell surfaces compared to cells incubated with medium alone. In contrast, surface expression of CD11b and CD49d in EoL-1 cells was not affected by D. farinae extract. In addition, pretreatment of cells with NF-kappaB inhibitor (MG-132) or JNK inhibitor (SP600125) significantly inhibited ICAM-1 expression promoted by HDM extract. However, neither p38 MAP kinase inhibitor nor MEK inhibitor prevented HDM-induced ICAM-1 expression in EoL-1 cells. These results suggest that crude extract of D. farinae induces ICAM-1 expression in EoL-1 cells through signaling pathways involving both NF-kappaB and JNK.

  1. House Dust Mite Induces Expression of Intercellular Adhesion Molecule-1 in EoL-1 Human Eosinophilic Leukemic Cells

    PubMed Central

    Kwon, Byoung Chul; Sohn, Myung Hyun; Kim, Kyung Won; Kim, Eun Soo; Kim, Kyu-Earn

    2007-01-01

    The house dust mite (HDM) is considered to be the most common indoor allergen associated with bronchial asthma. In this study, we investigated whether crude extract of the HDM Dermatophagoides farinae could activate human eosinophilic leukemic cells (EoL-1) to induce upregulation of cell-surface adhesion molecules. When EoL-1 cells were incubated with D. farinae extract, expression of intercellular adhesion molecule-1 (ICAM-1) significantly increased on the cell surfaces compared to cells incubated with medium alone. In contrast, surface expression of CD11b and CD49d in EoL-1 cells was not affected by D. farinae extract. In addition, pretreatment of cells with NF-κB inhibitor (MG-132) or JNK inhibitor (SP600125) significantly inhibited ICAM-1 expression promoted by HDM extract. However, neither p38 MAP kinase inhibitor nor MEK inhibitor prevented HDM-induced ICAM-1 expression in EoL-1 cells. These results suggest that crude extract of D. farinae induces ICAM-1 expression in EoL-1 cells through signaling pathways involving both NF-κB and JNK. PMID:17982228

  2. Neutrophil recruitment limited by high-affinity bent β2 integrin binding ligand in cis

    PubMed Central

    Fan, Zhichao; McArdle, Sara; Marki, Alex; Mikulski, Zbigniew; Gutierrez, Edgar; Engelhardt, Britta; Deutsch, Urban; Ginsberg, Mark; Groisman, Alex; Ley, Klaus

    2016-01-01

    Neutrophils are essential for innate immunity and inflammation and many neutrophil functions are β2 integrin-dependent. Integrins can extend (E+) and acquire a high-affinity conformation with an ‘open' headpiece (H+). The canonical switchblade model of integrin activation proposes that the E+ conformation precedes H+, and the two are believed to be structurally linked. Here we show, using high-resolution quantitative dynamic footprinting (qDF) microscopy combined with a homogenous conformation-reporter binding assay in a microfluidic device, that a substantial fraction of β2 integrins on human neutrophils acquire an unexpected E−H+ conformation. E−H+ β2 integrins bind intercellular adhesion molecules (ICAMs) in cis, which inhibits leukocyte adhesion in vitro and in vivo. This endogenous anti-inflammatory mechanism inhibits neutrophil aggregation, accumulation and inflammation. PMID:27578049

  3. 75 FR 31791 - Government-Owned Inventions; Availability for Licensing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-04

    ... reveal the genetic processes occurring in ccRCC tissues that may contribute to advanced disease. Positive... transformed into blood brain barrier permeable forms by the coupling of an Inter-Cellular Adhesion Molecule-1...

  4. Early life adversity and inflammation in African Americans and whites in the midlife in the United States survey.

    PubMed

    Slopen, Natalie; Lewis, Tené T; Gruenewald, Tara L; Mujahid, Mahasin S; Ryff, Carol D; Albert, Michelle A; Williams, David R

    2010-09-01

    To determine whether early life adversity (ELA) was predictive of inflammatory markers and to determine the consistency of these associations across racial groups. We analyzed data from 177 African Americans and 822 whites aged 35 to 86 years from two preliminary subsamples of the Midlife in the United States biomarker study. ELA was measured via retrospective self-report. We used multivariate linear regression models to examine the associations between ELA and C-reactive protein, interleukin-6, fibrinogen, endothelial leukocyte adhesion molecule-1, and soluble intercellular adhesion molecule-1, independent of age, gender, and medications. We extended race-stratified models to test three potential mechanisms for the observed associations. Significant interactions between ELA and race were observed for all five biomarkers. Models stratified by race revealed that ELA predicted higher levels of log interleukin-6, fibrinogen, endothelial leukocyte adhesion molecule-1, and soluble intercellular adhesion molecule-1 among African Americans (p < .05), but not among whites. Some, but not all, of these associations were attenuated after adjustment for health behaviors and body mass index, adult stressors, and depressive symptoms. ELA was predictive of high concentrations of inflammatory markers at midlife for African Americans, but not whites. This pattern may be explained by an accelerated course of age-related disease development for African Americans.

  5. The mechanism of the growth-inhibitory effect of coxsackie and adenovirus receptor (CAR) on human bladder cancer: a functional analysis of car protein structure.

    PubMed

    Okegawa, T; Pong, R C; Li, Y; Bergelson, J M; Sagalowsky, A I; Hsieh, J T

    2001-09-01

    The coxsackie and adenovirus receptor (CAR) is identified as a high-affinity receptor for adenovirus type 5. We observed that invasive bladder cancer specimens had significantly reduced CAR mRNA levels compared with superficial bladder cancer specimens, which suggests that CAR may play a role in the progression of bladder cancer. Elevated CAR expression in the T24 cell line (CAR-negative cells) increased its sensitivity to adenovirus infection and significantly inhibited its in vitro growth, accompanied by p21 and hypophosphorylated retinoblastoma accumulation. Conversely, decreased CAR levels in both RT4 and 253J cell lines (CAR-positive cells) promoted their in vitro growth. To unveil the mechanism of action of CAR, we showed that the extracellular domain of CAR facilitated intercellular adhesion. Furthermore, interrupting intercellular adhesion of CAR by a specific antibody alleviates the growth-inhibitory effect of CAR. We also demonstrated that both the transmembrane and intracellular domains of CAR were critical for its growth-inhibitory activity. These data indicate that the cell-cell contact initiated by membrane-bound CAR can elicit a negative signal cascade to modulate cell cycle regulators inside the nucleus of bladder cancer cells. Therefore, the presence of CAR cannot only facilitate viral uptake of adenovirus but also inhibit cell growth. These results can be integrated to formulate a new strategy for bladder cancer therapy.

  6. Ursolic acid, a natural pentacyclic triterpenoid, inhibits intracellular trafficking of proteins and induces accumulation of intercellular adhesion molecule-1 linked to high-mannose-type glycans in the endoplasmic reticulum

    PubMed Central

    Mitsuda, Satoshi; Yokomichi, Tomonobu; Yokoigawa, Junpei; Kataoka, Takao

    2014-01-01

    Ursolic acid (3β-hydroxy-urs-12-en-28-oic acid) is a natural pentacyclic triterpenoid that is present in many plants, including medicinal herbs, and foods. Ursolic acid was initially identified as an inhibitor of the expression of intercellular adhesion molecule-1 (ICAM-1) in response to interleukin-1α (IL-1α). We report here a novel biological activity: ursolic acid inhibits intracellular trafficking of proteins. Ursolic acid markedly inhibited the IL-1α-induced cell-surface ICAM-1 expression in human cancer cell lines and human umbilical vein endothelial cells. By contrast, ursolic acid exerted weak inhibitory effects on the IL-1α-induced ICAM-1 expression at the protein level. Surprisingly, we found that ursolic acid decreased the apparent molecular weight of ICAM-1 and altered the structures of N-linked oligosaccharides bound to ICAM-1. Ursolic acid induced the accumulation of ICAM-1 in the endoplasmic reticulum, which was linked mainly to high-mannose-type glycans. Moreover, in ursolic-acid-treated cells, the Golgi apparatus was fragmented into pieces and distributed over the cells. Thus, our results reveal that ursolic acid inhibits intracellular trafficking of proteins and induces the accumulation of ICAM-1 linked to high-mannose-type glycans in the endoplasmic reticulum. PMID:24649404

  7. Expression pattern of adhesion molecules in junctional epithelium differs from that in other gingival epithelia.

    PubMed

    Hatakeyama, S; Yaegashi, T; Oikawa, Y; Fujiwara, H; Mikami, T; Takeda, Y; Satoh, M

    2006-08-01

    The gingival epithelium is the physiologically important interface between the bacterially colonized gingival sulcus and periodontal soft and mineralized connective tissues, requiring protection from exposure to bacteria and their products. However, of the three epithelia comprising the gingival epithelium, the junctional epithelium has much wider intercellular spaces than the sulcular epithelium and oral gingival epithelium. Hence, the aim of the present study was to characterize the cell adhesion structure in the junctional epithelium compared with the other two epithelia. Gingival epithelia excised at therapeutic flap surgery from patients with periodontitis were examined for expression of adhesion molecules by immunofluorescence. In the oral gingival epithelium and sulcular epithelium, but not in the junctional epithelium, desmoglein 1 and 2 in cell-cell contact sites were more abundant in the upper than the suprabasal layers. E-cadherin, the main transmembranous molecule of adherens junctions, was present in spinous layers of the oral gingival epithelium and sulcular epithelium, but was scarce in the junctional epithelium. In contrast, desmoglein 3 and P-cadherin were present in all layers of the junctional epithelium as well as the oral gingival epithelium and sulcular epithelium. Connexin 43 was clearly localized to spinous layers of the oral gingival epithelium, sulcular epithelium and parts of the junctional epithelium. Claudin-1 and occludin were expressed in the cell membranes of a few superficial layers of the oral gingival epithelium. These findings indicated that the junctional epithelium contains only a few desmosomes, composed of only desmoglein 3; adherens junctions are probably absent because of defective E-cadherin. Thus, the anchoring junctions connecting junctional epithelium cells are lax, causing widened intercellular spaces. In contrast, the oral gingival epithelium, which has a few tight junctions, functions as a barrier.

  8. MHC class I, MHC class II and intercellular adhesion molecule-1 (ICAM-1) expression in inflammatory myopathies.

    PubMed

    Bartoccioni, E; Gallucci, S; Scuderi, F; Ricci, E; Servidei, S; Broccolini, A; Tonali, P

    1994-01-01

    We investigated the relationship between the MHC-I, MHC-II and intercellular adhesion molecule-1 (ICAM-1) expression on myofibres and the presence of inflammatory cells in muscle specimens of 18 patients with inflammatory myopathies (nine polymyositis, seven dermatomyositis, two inclusion body myositis). We observed MHC-I expression in muscle fibres, infiltrating mononuclear cells and endothelial cells in every specimen. In seven patients, some muscle fibres were MHC-II-positive for the DR antigen, while the DP and DQ antigens were absent. ICAM-1 expression, detected in seven patients, was found in clusters of myofibres, associated with a marked MHC-I positivity and a widespread mononuclear infiltration. Most of the ICAM-1-positive fibres were regenerating fibres. Furthermore, some fibres expressed both ICAM-1 and DR antigens near infiltrating cells. This finding could support the hypothesis that myofibres may themselves be the site of autosensitization.

  9. Intercellular adhesion molecule-1 expression by skeletal muscle cells augments myogenesis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Goh, Qingnian; Dearth, Christopher L.; Corbett, Jacob T.

    We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast–myoblast adhesion, myotube formation,more » myonuclear number, myotube alignment, myotube–myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube–myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. - Highlights: • We examined mechanisms through which skeletal muscle cell expression of ICAM-1 facilitates events of in vitro myogenesis. • Expression of ICAM-1 by cultured myoblasts did not influence their ability to proliferate or differentiate. • Skeletal muscle cell expression of ICAM-1 augmented myoblast fusion, myotube alignment, myotube–myotube fusion, and myotube size. • ICAM-1 augmented myogenic processes through mechanisms involving its adhesive and signaling functions.« less

  10. Simulated microgravity does not alter epithelial cell adhesion to matrix and other molecules

    NASA Technical Reports Server (NTRS)

    Jessup, J. M.; Brown, K.; Ishii, S.; Ford, R.; Goodwin, T. J.; Spaulding, G.

    1994-01-01

    Microgravity has advantages for the cultivation of tissues with high fidelity; however, tissue formation requires cellular recognition and adhesion. We tested the hypothesis that simulated microgravity does not affect cell adhesion. Human colorectal carcinoma cells were cultured in the NASA Rotating Wall Vessel (RWV) under low shear stress with randomization of the gravity vector that simulates microgravity. After 6 - 7 days, cells were assayed for binding to various substrates and compared to cells grown in standard tissue culture flasks and static suspension cultures. The RWV cultures bound as well to basement membrane proteins and to Carcinoembryonic Antigen (CEA), an intercellular adhesion molecule, as control cultures did. Thus, microgravity does not alter epithelial cell adhesion and may be useful for tissue engineering.

  11. Soluble intercellular adhesion molecule-1 and interleukin-6 levels reflect endothelial dysfunction in patients with primary hypercholesterolaemia treated with atorvastatin.

    PubMed

    Nawawi, H; Osman, N S; Annuar, R; Khalid, B A K; Yusoff, K

    2003-08-01

    Adhesion molecules and cytokines are involved in the pathogenesis of intimal injury in atherosclerosis but their relationship with endothelial function remains unclear. The objectives of this study were to examine the effects of atorvastatin on soluble adhesion molecules, interleukin-6 (IL-6) and brachial artery endothelial-dependent flow mediated dilatation (FMD) in patients with familial (FH) and non-familial hypercholesterolaemia (NFH). A total of 74 patients (27 FH and 47 NFH) were recruited. Fasting lipid profiles, soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular-cellular adhesion molecule-1 (sVCAM-1), E-selectin, IL-6 and FMD were measured at baseline, 2 weeks, 3 and 9 months post-atorvastatin treatment (FH--80 mg/day, NFH--10 mg/day). In both groups, compared to baseline, sICAM-1 levels were significantly reduced at 2 weeks, further reduced at 3 months and maintained at 9 months (P<0.0001). The IL-6 levels were significantly reduced at 3 months and 9 months compared to baseline for FH (P<0.005) and NFH (P<0.0001). In both groups, the FMD at 2 weeks was higher than baseline (P<0.005), with progressive improvement up to 9 months. FMD was negatively correlated with sICAM-1 and IL-6. In conclusion, both low and high doses of atorvastatin lead to early progressive improvement in endothelial function in patients with primary hypercholesterolaemia. sICAM-1 and IL-6 levels reflect endothelial dysfunction in these patients.

  12. Polarized release of T-cell-receptor-enriched microvesicles at the immunological synapse.

    PubMed

    Choudhuri, Kaushik; Llodrá, Jaime; Roth, Eric W; Tsai, Jones; Gordo, Susana; Wucherpfennig, Kai W; Kam, Lance C; Stokes, David L; Dustin, Michael L

    2014-03-06

    The recognition events that mediate adaptive cellular immunity and regulate antibody responses depend on intercellular contacts between T cells and antigen-presenting cells (APCs). T-cell signalling is initiated at these contacts when surface-expressed T-cell receptors (TCRs) recognize peptide fragments (antigens) of pathogens bound to major histocompatibility complex molecules (pMHC) on APCs. This, along with engagement of adhesion receptors, leads to the formation of a specialized junction between T cells and APCs, known as the immunological synapse, which mediates efficient delivery of effector molecules and intercellular signals across the synaptic cleft. T-cell recognition of pMHC and the adhesion ligand intercellular adhesion molecule-1 (ICAM-1) on supported planar bilayers recapitulates the domain organization of the immunological synapse, which is characterized by central accumulation of TCRs, adjacent to a secretory domain, both surrounded by an adhesive ring. Although accumulation of TCRs at the immunological synapse centre correlates with T-cell function, this domain is itself largely devoid of TCR signalling activity, and is characterized by an unexplained immobilization of TCR-pMHC complexes relative to the highly dynamic immunological synapse periphery. Here we show that centrally accumulated TCRs are located on the surface of extracellular microvesicles that bud at the immunological synapse centre. Tumour susceptibility gene 101 (TSG101) sorts TCRs for inclusion in microvesicles, whereas vacuolar protein sorting 4 (VPS4) mediates scission of microvesicles from the T-cell plasma membrane. The human immunodeficiency virus polyprotein Gag co-opts this process for budding of virus-like particles. B cells bearing cognate pMHC receive TCRs from T cells and initiate intracellular signals in response to isolated synaptic microvesicles. We conclude that the immunological synapse orchestrates TCR sorting and release in extracellular microvesicles. These microvesicles deliver transcellular signals across antigen-dependent synapses by engaging cognate pMHC on APCs.

  13. Polarized release of T-cell-receptor-enriched microvesicles at the immunological synapse

    NASA Astrophysics Data System (ADS)

    Choudhuri, Kaushik; Llodrá, Jaime; Roth, Eric W.; Tsai, Jones; Gordo, Susana; Wucherpfennig, Kai W.; Kam, Lance C.; Stokes, David L.; Dustin, Michael L.

    2014-03-01

    The recognition events that mediate adaptive cellular immunity and regulate antibody responses depend on intercellular contacts between T cells and antigen-presenting cells (APCs). T-cell signalling is initiated at these contacts when surface-expressed T-cell receptors (TCRs) recognize peptide fragments (antigens) of pathogens bound to major histocompatibility complex molecules (pMHC) on APCs. This, along with engagement of adhesion receptors, leads to the formation of a specialized junction between T cells and APCs, known as the immunological synapse, which mediates efficient delivery of effector molecules and intercellular signals across the synaptic cleft. T-cell recognition of pMHC and the adhesion ligand intercellular adhesion molecule-1 (ICAM-1) on supported planar bilayers recapitulates the domain organization of the immunological synapse, which is characterized by central accumulation of TCRs, adjacent to a secretory domain, both surrounded by an adhesive ring. Although accumulation of TCRs at the immunological synapse centre correlates with T-cell function, this domain is itself largely devoid of TCR signalling activity, and is characterized by an unexplained immobilization of TCR-pMHC complexes relative to the highly dynamic immunological synapse periphery. Here we show that centrally accumulated TCRs are located on the surface of extracellular microvesicles that bud at the immunological synapse centre. Tumour susceptibility gene 101 (TSG101) sorts TCRs for inclusion in microvesicles, whereas vacuolar protein sorting 4 (VPS4) mediates scission of microvesicles from the T-cell plasma membrane. The human immunodeficiency virus polyprotein Gag co-opts this process for budding of virus-like particles. B cells bearing cognate pMHC receive TCRs from T cells and initiate intracellular signals in response to isolated synaptic microvesicles. We conclude that the immunological synapse orchestrates TCR sorting and release in extracellular microvesicles. These microvesicles deliver transcellular signals across antigen-dependent synapses by engaging cognate pMHC on APCs.

  14. Loss of intercellular adhesion leads to differential accumulation of hypericin in bladder cancer

    NASA Astrophysics Data System (ADS)

    Lucky, S. Sasidharan; Bhuvaneswari, Ramaswamy; Chin, William W. L.; Lau, Weber K. O.; Olivo, Malini C. D.

    2009-06-01

    Photodynamic diagnosis (PDD) exploits the photoactive nature of certain compounds, namely photosensitizers, in order to enhance the visual demarcation between normal and neoplastic tissue. Hypericin is one such potent photosensitizer that preferentially accumulate in neoplastic tissue, and fluoresce in the visible spectrum when illuminated with light of an appropriate wavelength. In our study, we investigated the role of E-cadherin in the selective permeation of hypericin in bladder cancer tissues. Clinical studies were done on a series of 43 histologically graded bladder cancer biopsy specimens, obtained from 28 patients who received intravesical instillations with 8μM hypericin solution for at least 2 hours. Immunohistochemical staining was used to assess the expression of E-cadherin, in the cryosectioned tissues. Hypericin uptake was examined by fluorescence microscopy. Immunohistochemical staining showed a clear expression of E-cadherin along the urothelial lining of the normal and pre-malignant tissues. Partial expression of these cell adhesion molecules were still observed in malignant tissues, however there was a loss of expression to variable extends along the urothelium. Thus, loss of intercellular adhesion can be associated with enhanced hypericin permeation through paracellular diffusion.

  15. [Expression of cell adhesion molecules in acute leukemia cell].

    PubMed

    Ju, Xiaoping; Peng, Min; Xu, Xiaoping; Lu, Shuqing; Li, Yao; Ying, Kang; Xie, Yi; Mao, Yumin; Xia, Fang

    2002-11-01

    To investigate the role of cell adhesion molecule in the development and extramedullary infiltration (EI) of acute leukemia. The expressions of neural cell adhesion molecule (NCAM) gene, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule (VCAM-1) genes in 25 acute leukemia patients bone marrow cells were detected by microarray and reverse transcriptase-polymerase chain reaction (RT-PCR). The expressions of NCAM, ICAM-1 and VCAM-1 gene were significantly higher in acute leukemia cells and leukemia cells with EI than in normal tissues and leukemia cells without EI, respectively, both by cDNA microarray and by RT-PCR. The cDNA microarray is a powerful technique in analysis of acute leukemia cells associated genes. High expressions of cell adhesion molecule genes might be correlated with leukemia pathogenesis and infiltration of acute leukemia cell.

  16. Intercellular adhesion molecule, plasma adiponectin and albuminuria in type 2 diabetic patients.

    PubMed

    Lenghel, Alina Ramona; Kacso, Ina Maria; Bondor, Cosmina Ioana; Rusu, Crina; Rahaian, Rodica; Gherman Caprioara, Mirela

    2012-01-01

    Our study addressed the influence of early inflammatory stages of diabetic kidney disease: leukocyte adhesion and monocyte activation (as assessed by intercellular leukocyte adhesion molecule-ICAM-1 and monocyte chemoatractant protein-MCP-1) on the degree of albuminuria. Plasma levels of adiponectin, a possible anti-inflammatory counteracting mechanism, were also studied in correlation to the above-mentioned cytokines. 79 consecutive type 2 diabetic outpatients and 46 controls were included. Routine laboratory analysis, urinary albumin to creatinine ratio (uACR), plasma adiponectin, plasma ICAM-1 and urinary MPC-1 were assessed. In multiple regression ICAM-1 (p=0.004) and adiponectin (p=0.04) were the main determinants of uACR. Plasma adiponectin positively correlated to ICAM-1 (p=0.03, r=0.24). In albuminuric patients (uACR ≥30 mg/g) plasma adiponectin was significantly higher compared to normoalbuminuric ones (uACR <30 mg/g). In albuminuric patients the main determinants of uACR were plasma ICAM-1 and adiponectin. In multiple regression ICAM-1 is the only one that retains statistical significance (p=0.02). Urinary MCP-1 did not correlate to uACR. In our type 2 diabetic patients, plasma levels of ICAM-1 and adiponectin are predictive for albuminuria. Urinary MCP-1 does not correlated to uACR. Plasma adiponectin positively correlates to adhesion molecule ICAM-1 in our cohort. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  17. The Lymphocyte Function–associated Antigen 1 I Domain Is a Transient Binding Module for Intercellular Adhesion Molecule (ICAM)-1 and ICAM-3 in Hydrodynamic Flow

    PubMed Central

    Knorr, Ruth; Dustin, Michael L.

    1997-01-01

    The I domain of lymphocyte function–associated antigen (LFA)-1 contains an intercellular adhesion molecule (ICAM)-1 and ICAM-3 binding site, but the relationship of this site to regulated adhesion is unknown. To study the adhesive properties of the LFA-1 I domain, we stably expressed a GPI-anchored form of this I domain (I-GPI) on the surface of baby hamster kidney cells. I-GPI cells bound soluble ICAM-1 (sICAM-1) with a low avidity and affinity. Flow cell experiments demonstrated a specific rolling interaction of I-GPI cells on bilayers containing purified full length ICAM-1 or ICAM-3. The LFA-1 activating antibody MEM-83, or its Fab fragment, decreased the rolling velocity of I-GPI cells on ICAM-1–containing membranes. In contrast, the interaction of I-GPI cells with ICAM-3 was blocked by MEM-83. Rolling of I-GPI cells was dependent on the presence of Mg2+. Mn2+ only partially substituted for Mg2+, giving rise to a small fraction of rolling cells and increased rolling velocity. This suggests that the I domain acts as a transient, Mg2+-dependent binding module that cooperates with another Mn2+-stimulated site in LFA-1 to give rise to the stable interaction of intact LFA-1 with ICAM-1. PMID:9271587

  18. Expression of Inflammation-related Intercellular Adhesion Molecules in Cardiomyocytes In Vitro and Modulation by Pro-inflammatory Agents.

    PubMed

    El-Battrawy, Ibrahim; Tülümen, Erol; Lang, Siegfried; Akin, Ibrahim; Behnes, Michael; Zhou, Xiabo; Mavany, Martin; Bugert, Peter; Bieback, Karen; Borggrefe, Martin; Elmas, Elif

    2016-01-01

    Cell-surface adhesion molecules regulate multiple intercellular and intracellular processes and play important roles in inflammation by facilitating leukocyte endothelial transmigration. Whether cardiomyocytes express surface-adhesion molecules related to inflammation and the effect of pro-inflammatory mediators remain unknown. In the present study, the expression of different cell-adhesion molecules (CD11a, CD11b, CD31, CD62P, CD162, F11 receptor and mucosal vascular addressin cell adhesion molecule 1 (MADCAM1)) and the effect of pro-inflammatory mediators were investigated in an in vitro model of human cardiomyocytes. Cells were supplied as a primary culture of cardiac alpha actin-positive cells from human heart tissue. The cells were incubated for 24 h with 1 U/ml thrombin or 700 ng/ml lipopolysaccharide (LPS) or with a combination of both. The expression of the cell adhesion molecules was measured by flow cytometry. In cultured human cardiomyocytes, 22.8% of cells expressed CD31, 7.1% MADCAM1 and 2.6% F11R. CD11a, CD11b, CD62P and CD162 were expressed by fewer than 2% of the cells at baseline. CD31 expression increased on incubation of cardiomyocytes with thrombin by 26% (p<0.05) and with LPS by 26% (p=0.06). The combination of thrombin and LPS did not result in increased levels of CD31 (p>0.10). The pro-inflammatory agents LPS and thrombin had no effect on the expression of MADCAM1 and F11R. Inflammation-related cell-adhesion molecules CD31, MADCAM1 and F11R were shown to be expressed on the surface of human cardiomyocytes in an in vitro model. Incubation with LPS or thrombin resulted in increased expression of CD31, however, it did not modify the expression of the cell adhesion molecules MADCAM1 and F11R. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  19. Down-regulation of POLYGALACTURONASE1 alters firmness, tensile strength and water loss in apple (Malus x domestica) fruit.

    PubMed

    Atkinson, Ross G; Sutherland, Paul W; Johnston, Sarah L; Gunaseelan, Kularajathevan; Hallett, Ian C; Mitra, Deepali; Brummell, David A; Schröder, Roswitha; Johnston, Jason W; Schaffer, Robert J

    2012-08-02

    While there is now a significant body of research correlating apple (Malus x domestica) fruit softening with the cell wall hydrolase ENDO-POLYGALACTURONASE1 (PG1), there is currently little knowledge of its physiological effects in planta. This study examined the effect of down regulation of PG1 expression in 'Royal Gala' apples, a cultivar that typically has high levels of PG1, and softens during fruit ripening. PG1-suppressed 'Royal Gala' apples harvested from multiple seasons were firmer than controls after ripening, and intercellular adhesion was higher. Cell wall analyses indicated changes in yield and composition of pectin, and a higher molecular weight distribution of CDTA-soluble pectin. Structural analyses revealed more ruptured cells and free juice in pulled apart sections, suggesting improved integrity of intercellular connections and consequent cell rupture due to failure of the primary cell walls under stress. PG1-suppressed lines also had reduced expansion of cells in the hypodermis of ripe apples, resulting in more densely packed cells in this layer. This change in morphology appears to be linked with reduced transpirational water loss in the fruit. These findings confirm PG1's role in apple fruit softening and suggests that this is achieved in part by reducing cellular adhesion. This is consistent with previous studies carried out in strawberry but not with those performed in tomato. In apple PG1 also appears to influence other fruit texture characters such as juiciness and water loss.

  20. Modulation of the degree and pattern of methyl-esterification of pectic homogalacturonan in plant cell walls. Implications for pectin methyl esterase action, matrix properties, and cell adhesion.

    PubMed

    Willats, W G; Orfila, C; Limberg, G; Buchholt, H C; van Alebeek, G J; Voragen, A G; Marcus, S E; Christensen, T M; Mikkelsen, J D; Murray, B S; Knox, J P

    2001-06-01

    Homogalacturonan (HG) is a multifunctional pectic polysaccharide of the primary cell wall matrix of all land plants. HG is thought to be deposited in cell walls in a highly methyl-esterified form but can be subsequently de-esterified by wall-based pectin methyl esterases (PMEs) that have the capacity to remove methyl ester groups from HG. Plant PMEs typically occur in multigene families/isoforms, but the precise details of the functions of PMEs are far from clear. Most are thought to act in a processive or blockwise fashion resulting in domains of contiguous de-esterified galacturonic acid residues. Such de-esterified blocks of HG can be cross-linked by calcium resulting in gel formation and can contribute to intercellular adhesion. We demonstrate that, in addition to blockwise de-esterification, HG with a non-blockwise distribution of methyl esters is also an abundant feature of HG in primary plant cell walls. A partially methyl-esterified epitope of HG that is generated in greatest abundance by non-blockwise de-esterification is spatially regulated within the cell wall matrix and occurs at points of cell separation at intercellular spaces in parenchymatous tissues of pea and other angiosperms. Analysis of the properties of calcium-mediated gels formed from pectins containing HG domains with differing degrees and patterns of methyl-esterification indicated that HG with a non-blockwise pattern of methyl ester group distribution is likely to contribute distinct mechanical and porosity properties to the cell wall matrix. These findings have important implications for our understanding of both the action of pectin methyl esterases on matrix properties and mechanisms of intercellular adhesion and its loss in plants.

  1. Expression of intercellular adhesion molecule-1 by myofibers in mdx mice.

    PubMed

    Torres-Palsa, Maria J; Koziol, Matthew V; Goh, Qingnian; Cicinelli, Peter A; Peterson, Jennifer M; Pizza, Francis X

    2015-11-01

    We investigated the extent to which intercellular adhesion molecule-1 (ICAM-1), a critical protein of the inflammatory response, is expressed in skeletal muscles of mdx mice (a murine model of Duchenne muscular dystrophy). Muscles were collected from control and mdx mice at 2-24 weeks of age and analyzed for ICAM-1 expression by means of Western blot and immunofluorescence. Western blot revealed higher expression of ICAM-1 in mdx compared with control muscles through 24 weeks of age. In contrast to control muscles, ICAM-1 was expressed on the membrane of damaged, regenerating, and normal myofibers of mdx mice. CD11b+ myeloid cells also expressed ICAM-1 in mdx muscles, and CD11b+ cells were closely associated with the membrane of myofibers expressing ICAM-1. These findings support a paradigm in which ICAM-1 and its localization to myofibers in muscles of mdx mice contributes to the dystrophic pathology. © 2015 Wiley Periodicals, Inc.

  2. EXPRESSION OF INTERCELLULAR ADHESION MOLECULE-1 BY MYOFIBERS IN mdx MICE

    PubMed Central

    TORRES-PALSA, MARIA J.; KOZIOL, MATTHEW V.; GOH, QINGNIAN; CICINELLI, PETER A.; PETERSON, JENNIFER M.; PIZZA, FRANCIS X.

    2017-01-01

    Introduction We investigated the extent to which intercellular adhesion molecule-1 (ICAM-1), a critical protein of the inflammatory response, is expressed in skeletal muscles of mdx mice (a murine model of Duchenne muscular dystrophy). Methods Muscles were collected from control and mdx mice at 2–24 weeks of age and analyzed for ICAM-1 expression by means of Western blot and immunofluorescence. Results Western blot revealed higher expression of ICAM-1 in mdx compared with control muscles through 24 weeks of age. In contrast to control muscles, ICAM-1 was expressed on the membrane of damaged, regenerating, and normal myofibers of mdx mice. CD11b+ myeloid cells also expressed ICAM-1 in mdx muscles, and CD11b+ cells were closely associated with the membrane of myofibers expressing ICAM-1. Conclusions These findings support a paradigm in which ICAM-1 and its localization to myofibers in muscles of mdx mice contributes to the dystrophic pathology. PMID:25728314

  3. Regulation of Endothelial Adherens Junctions by Tyrosine Phosphorylation

    PubMed Central

    Adam, Alejandro Pablo

    2015-01-01

    Endothelial cells form a semipermeable, regulated barrier that limits the passage of fluid, small molecules, and leukocytes between the bloodstream and the surrounding tissues. The adherens junction, a major mechanism of intercellular adhesion, is comprised of transmembrane cadherins forming homotypic interactions between adjacent cells and associated cytoplasmic catenins linking the cadherins to the cytoskeleton. Inflammatory conditions promote the disassembly of the adherens junction and a loss of intercellular adhesion, creating openings or gaps in the endothelium through which small molecules diffuse and leukocytes transmigrate. Tyrosine kinase signaling has emerged as a central regulator of the inflammatory response, partly through direct phosphorylation and dephosphorylation of the adherens junction components. This review discusses the findings that support and those that argue against a direct effect of cadherin and catenin phosphorylation in the disassembly of the adherens junction. Recent findings indicate a complex interaction between kinases, phosphatases, and the adherens junction components that allow a fine regulation of the endothelial permeability to small molecules, leukocyte migration, and barrier resealing. PMID:26556953

  4. Mutations in CTNNA1 cause butterfly-shaped pigment dystrophy and perturbed retinal pigment epithelium integrity

    PubMed Central

    Saksens, Nicole T.M.; Krebs, Mark P.; Schoenmaker-Koller, Frederieke E.; Hicks, Wanda; Yu, Minzhong; Shi, Lanying; Rowe, Lucy; Collin, Gayle B.; Charette, Jeremy R.; Letteboer, Stef J.; Neveling, Kornelia; van Moorsel, Tamara W.; Abu-Ltaif, Sleiman; De Baere, Elfride; Walraedt, Sophie; Banfi, Sandro; Simonelli, Francesca; Cremers, Frans P.M.; Boon, Camiel J.F.; Roepman, Ronald; Leroy, Bart P.; Peachey, Neal S.; Hoyng, Carel B.; Nishina, Patsy M.; den Hollander, Anneke I.

    2015-01-01

    Butterfly-shaped pigment dystrophy is an eye disease characterized by lesions in the macula that can resemble the wings of a butterfly. Here, we report the identification of heterozygous missense mutations in the α-catenin 1 (CTNNA1) gene in three families with butterfly-shaped pigment dystrophy. In addition, we identified a Ctnna1 missense mutation in a chemically induced mouse mutant, tvrm5. Parallel clinical phenotypes were observed in the retinal pigment epithelium (RPE) of individuals with butterfly-shaped pigment dystrophy and in tvrm5 mice, including pigmentary abnormalities, focal thickening and elevated lesions, and decreased light-activated responses. Morphological studies in tvrm5 mice revealed increased cell shedding and large multinucleated RPE cells, suggesting defects in intercellular adhesion and cytokinesis. This study identifies CTNNA1 gene variants as a cause of macular dystrophy, suggests that CTNNA1 is involved in maintaining RPE integrity, and suggests that other components that participate in intercellular adhesion may be implicated in macular disease. PMID:26691986

  5. MHC class I, MHC class II and intercellular adhesion molecule-1 (ICAM-1) expression in inflammatory myopathies.

    PubMed Central

    Bartoccioni, E; Gallucci, S; Scuderi, F; Ricci, E; Servidei, S; Broccolini, A; Tonali, P

    1994-01-01

    We investigated the relationship between the MHC-I, MHC-II and intercellular adhesion molecule-1 (ICAM-1) expression on myofibres and the presence of inflammatory cells in muscle specimens of 18 patients with inflammatory myopathies (nine polymyositis, seven dermatomyositis, two inclusion body myositis). We observed MHC-I expression in muscle fibres, infiltrating mononuclear cells and endothelial cells in every specimen. In seven patients, some muscle fibres were MHC-II-positive for the DR antigen, while the DP and DQ antigens were absent. ICAM-1 expression, detected in seven patients, was found in clusters of myofibres, associated with a marked MHC-I positivity and a widespread mononuclear infiltration. Most of the ICAM-1-positive fibres were regenerating fibres. Furthermore, some fibres expressed both ICAM-1 and DR antigens near infiltrating cells. This finding could support the hypothesis that myofibres may themselves be the site of autosensitization. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:7507012

  6. Two autonomous structural modules in the fimbrial shaft adhesin FimA mediate Actinomyces interactions with streptococci and host cells during oral biofilm development

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mishra, Arunima; Devarajan, Bharanidharan; Reardon, Melissa E.

    2011-09-06

    By combining X-ray crystallography and modelling, we describe here the atomic structure of distinct adhesive moieties of FimA, the shaft fimbrillin of Actinomyces type 2 fimbriae, which uniquely mediates the receptor-dependent intercellular interactions between Actinomyces and oral streptococci as well as host cells during the development of oral biofilms. The FimA adhesin is built with three IgG-like domains, each of which harbours an intramolecular isopeptide bond, previously described in several Gram-positive pilins. Genetic and biochemical studies demonstrate that although these isopeptide bonds are dispensable for fimbrial assembly, cell-cell interactions and biofilm formation, they contribute significantly to the proteolytic stability ofmore » FimA. Remarkably, FimA harbours two autonomous adhesive modules, which structurally resemble the Staphylococcus aureus Cna B domain. Each isolated module can bind the plasma glycoprotein asialofetuin as well as the polysaccharide receptors present on the surface of oral streptococci and epithelial cells. Thus, FimA should serve as an excellent paradigm for the development of therapeutic strategies and elucidating the precise molecular mechanisms underlying the interactions between cellular receptors and Gram-positive fimbriae.« less

  7. Two Autonomous Structural Modules in the Fimbrial Shaft Adhesin FimA Mediate Actinomyces Interactions with Streptococci and Host Cells during Oral Biofilm Development

    PubMed Central

    Mishra, Arunima; Devarajan, Bharanidharan; Reardon, Melissa E.; Dwivedi, Prabhat; Krishnan, Vengadesan; Cisar, John O.; Das, Asis; Narayana, Sthanam V. L; Ton-That, Hung

    2011-01-01

    By combining X-ray crystallography and modeling, we describe here the atomic structure of distinct adhesive moieties of FimA, the shaft fimbrillin of Actinomyces type 2 fimbriae, which uniquely mediates the receptor-dependent intercellular interactions between Actinomyces and oral streptococci as well as host cells during the development of oral biofilms. The FimA adhesin is built with three IgG-like domains, each of which harbors an intramolecular isopeptide bond, previously described in several Gram-positive pilins. Genetic and biochemical studies demonstrate that although these isopeptide bonds are dispensable for fimbrial assembly, cell-cell interactions and biofilm formation, they contribute significantly to the proteolytic stability of FimA. Remarkably, FimA harbors two autonomous adhesive modules, which structurally resemble the Staphylococcus aureus Cna B domain. Each isolated module can bind the plasma glycoprotein asialofetuin as well as the polysaccharide receptors present on the surface of oral streptococci and epithelial cells. Thus, FimA should serve as an excellent paradigm for the development of therapeutic strategies and elucidating the precise molecular mechanisms underlying the interactions between cellular receptors and Gram-positive fimbriae. PMID:21696465

  8. A molecular imaging analysis of C×43 association with Cdo during skeletal myoblast differentiation

    NASA Astrophysics Data System (ADS)

    Nosi, Daniele; Mercatelli, Raffaella; Chellini, Flaminia; Soria, Silvia; Pini, Alessandro; Formigli, Lucia; Quercioli, Franco

    2014-02-01

    Cell-to-cell contacts are crucial for cell differentiation. The promyogenic cell surface protein, Cdo, functions as a component of multiprotein clusters to mediate cell adhesion signaling. Connexin43, the main connexin forming gap junctions, also plays a key role in myogenesis. At least part of its effects are independent of the intercellular channel function, but the mechanisms underlying are unknown. Here, using multiple optical approaches, we provided the first evidence that Cx43 physically interacts with Cdo to form dynamic complexes during myoblast differentiation, offering clues for considering this interaction a structural basis of the channel-independent function of Cx43.

  9. [Effect of penicillin and the habitat medium in the body of bacterial carriers on the intercellular bonds in populations of the meningococcus and pertussis microbe].

    PubMed

    Vysotskiĭ, V V; Smirnova-Mutusheva, M A; Efimova, O G; Bakulina, N A

    1983-04-01

    The relationship of the bacterial cells in populations and their adhesion activity is at present one of the research priorities in microbiological studies. The stimulating effect of penicillin on the development of morphologically different intercellular bonds (IB) in populations of the pertussis causative agent and first of all derivatives or evaginates of the cell wall membranes was observed. Morphologically similar systems and polytubular IB were detected in populations of meningococcal strains isolated from carriers having no signs of the disease. Correlation between the after-effect of penicillin and the presence of the causative agent in bacterial carriers was shown. Unknown systems of interlacing tubular structures not directly bound with the cells, the walls of which were single contour membranes were determined in the meningococcal populations treated with penicillin. IB were observed in the population in the form of transpopulation cords. Morphologically different IB playing the role of specialized organelles might be considered as factors of the functional unity of the bacterial population as a multicellular system.

  10. Effect of 10-Week Supervised Moderate-Intensity Intermittent vs. Continuous Aerobic Exercise Programs on Vascular Adhesion Molecules in Patients with Heart Failure.

    PubMed

    Aksoy, Sibel; Findikoglu, Gulin; Ardic, Fusun; Rota, Simin; Dursunoglu, Dursun

    2015-10-01

    Abnormal expression of cellular adhesion molecules may be related to endothelial dysfunction, a key feature in chronic heart failure. This study compares the effects of 10-wk supervised moderate-intensity continuous aerobic exercise (CAE) and intermittent aerobic exercise (IAE) programs on markers of endothelial damage, disease severity, functional and metabolic status, and quality-of-life in chronic heart failure patients. Fifty-seven patients between 41 and 81 yrs with New York Heart Association class II-III chronic heart failure and with a left ventricular ejection fraction of 35%-55% were randomized into three groups: nonexercising control, CAE, and IAE, which exercised three times a week for 10 wks. Endothelial damage was assessed by serum markers of vascular cell adhesion molecule-1, serum intercellular adhesion molecule-1, and nitric oxide; disease severity was measured by left ventricular ejection fraction and N-terminal probrain natriuretic peptide; metabolic status was evaluated by body composition analysis and lipid profile levels; functional status was evaluated by cardiorespiratory exercise stress test and 6-min walking distance; quality-of-life was assessed with Left Ventricular Dysfunction-36 and Short-Form 36 questionnaires at the baseline and at the end of the 10th week. Significant decreases in serum vascular cell adhesion molecule-1 or serum intercellular adhesion molecule-1 in IAE and CAE groups after training were found, respectively. Resting systolic and diastolic blood pressure, peak systolic and diastolic blood pressure, 6-min walking distance, and the mental health and vitality components of Short-Form 36 improved in the CAE group, whereas left ventricular ejection fraction and 6-min walking distance improved in the IAE group compared with the control group. Both moderate-intensity CAE and IAE programs significantly reduced serum markers of adhesion molecules and prevented the change in VO2 in patients with chronic heart failure.

  11. αMβ2-integrin-intercellular adhesion molecule-1 interactions drive the flow-dependent trafficking of Guillain-Barré syndrome patient derived mononuclear leukocytes at the blood-nerve barrier in vitro

    PubMed Central

    Yosef, Nejla; Ubogu, Eroboghene E.

    2012-01-01

    The mechanisms of hematogenous leukocyte trafficking at the human blood-nerve barrier (BNB) are largely unknown. Intercellular adhesion molecule-1 (ICAM-1) has been implicated in the pathogenesis of Guillain-Barré syndrome (GBS). We developed a cytokine-activated human in vitro BNB model using primary endoneurial endothelial cells. Endothelial treatment with 10 U/mL tissue necrosis factor-α and 20 U/mL interferon-γ resulted in de novo expression of proinflammatory chemokines CCL2, CXCL9, CXCL11 and CCL20, with increased expression of CXCL2-3, CXCL8 and CXCL10 relative to basal levels. Cytokine treatment induced/ enhanced ICAM-1, E- and P-selectin, vascular cell adhesion molecule-1 and the alternatively spliced pro-adhesive fibronectin variant, fibronectin connecting segment-1 expression in a time-dependent manner, without alterations in junctional adhesion molecule-A expression. Lymphocytes and monocytes from untreated GBS patients express ICAM-1 counterligands, αM- and αL-integrin, with differential regulation of αM-integrin expression compared to healthy controls. Under flow conditions that mimic capillary hemodynamics in vivo, there was a >3-fold increase in total GBS patient and healthy control mononuclear leukocyte adhesion/ migration at the BNB following cytokine treatment relative to the untreated state. Function neutralizing monoclonal antibodies against human αM-integrin (CD11b) and ICAM-1 reduced untreated GBS patient mononuclear leukocyte trafficking at the BNB by 59% and 64.2% respectively. Monoclonal antibodies against αL-integrin (CD11a) and human intravenous immunoglobulin reduced total leukocyte adhesion/migration by 22.8% and 17.6% respectively. This study demonstrates differential regulation of αM-integrin on circulating mononuclear cells in GBS, as well as an important role for αM-integrin-ICAM-1 interactions in pathogenic GBS patient leukocyte trafficking at the human BNB in vitro. PMID:22552879

  12. Cytoadherence of Plasmodium falciparum to intercellular adhesion molecule 1 and chondroitin-4-sulfate expressed by the syncytiotrophoblast in the human placenta.

    PubMed Central

    Maubert, B; Guilbert, L J; Deloron, P

    1997-01-01

    Late stages of Plasmodium falciparum-infected erythrocytes (IRBCs) frequently sequester in the placentas of pregnant women, a phenomenon associated with low birth weight of the offspring. To investigate the physiological mechanism of this sequestration, we developed an in vitro assay for studying the cytoadherence of IRBCs to cultured term human trophoblasts. The capacity for binding to the syncytiotrophoblast varied greatly among P. falciparum isolates and was mediated by intercellular adhesion molecule 1 (ICAM-1), as binding was totally inhibited by 84H10, a monoclonal antibody specific for ICAM-1. Binding of the P. falciparum line RP5 to the syncytiotrophoblast involves chondroitin-4-sulfate (CSA), as this binding was dramatically impaired by addition of free CSA to the binding medium or by preincubation of the syncytiotrophoblast with chondroitinase ABC. ICAM-1 and CSA were visualized on the syncytiotrophoblast by immunofluorescence, while CD36, E-selectin, and vascular cell adhesion molecule 1 were not expressed even on tumor necrosis factor alpha (TNF-alpha)-stimulated syncytiotrophoblast tissue, and monoclonal antibodies against these cell adhesion molecules did not inhibit cytoadherence. ICAM-1 expression and cytoadherence of wild isolates was upregulated by TNF-alpha, a cytokine that can be secreted by the numerous mononuclear phagocytes present in malaria-infected placentas. These results suggest that cytoadherence may be involved in the placental sequestration and broaden the understanding of the physiopathology of the malaria-infected placenta. PMID:9119459

  13. Loss-of-Function Mutations in CAST Cause Peeling Skin, Leukonychia, Acral Punctate Keratoses, Cheilitis, and Knuckle Pads

    PubMed Central

    Lin, Zhimiao; Zhao, Jiahui; Nitoiu, Daniela; Scott, Claire A.; Plagnol, Vincent; Smith, Frances J.D.; Wilson, Neil J.; Cole, Christian; Schwartz, Mary E.; McLean, W.H. Irwin; Wang, Huijun; Feng, Cheng; Duo, Lina; Zhou, Eray Yihui; Ren, Yali; Dai, Lanlan; Chen, Yulan; Zhang, Jianguo; Xu, Xun; O’Toole, Edel A.; Kelsell, David P.; Yang, Yong

    2015-01-01

    Calpastatin is an endogenous specific inhibitor of calpain, a calcium-dependent cysteine protease. Here we show that loss-of-function mutations in calpastatin (CAST) are the genetic causes of an autosomal-recessive condition characterized by generalized peeling skin, leukonychia, acral punctate keratoses, cheilitis, and knuckle pads, which we propose to be given the acronym PLACK syndrome. In affected individuals with PLACK syndrome from three families of different ethnicities, we identified homozygous mutations (c.607dup, c.424A>T, and c.1750delG) in CAST, all of which were predicted to encode truncated proteins (p.Ile203Asnfs∗8, p.Lys142∗, and p.Val584Trpfs∗37). Immunohistochemistry shows that staining of calpastatin is reduced in skin from affected individuals. Transmission electron microscopy revealed widening of intercellular spaces with chromatin condensation and margination in the upper stratum spinosum in lesional skin, suggesting impaired intercellular adhesion as well as keratinocyte apoptosis. A significant increase of apoptotic keratinocytes was also observed in TUNEL assays. In vitro studies utilizing siRNA-mediated CAST knockdown revealed a role for calpastatin in keratinocyte adhesion. In summary, we describe PLACK syndrome, as a clinical entity of defective epidermal adhesion, caused by loss-of-function mutations in CAST. PMID:25683118

  14. Synaptopodin couples epithelial contractility to α-actinin-4–dependent junction maturation

    PubMed Central

    Kannan, Nivetha

    2015-01-01

    The epithelial junction experiences mechanical force exerted by endogenous actomyosin activities and from interactions with neighboring cells. We hypothesize that tension generated at cell–cell adhesive contacts contributes to the maturation and assembly of the junctional complex. To test our hypothesis, we used a hydraulic apparatus that can apply mechanical force to intercellular junction in a confluent monolayer of cells. We found that mechanical force induces α-actinin-4 and actin accumulation at the cell junction in a time- and tension-dependent manner during junction development. Intercellular tension also induces α-actinin-4–dependent recruitment of vinculin to the cell junction. In addition, we have identified a tension-sensitive upstream regulator of α-actinin-4 as synaptopodin. Synaptopodin forms a complex containing α-actinin-4 and β-catenin and interacts with myosin II, indicating that it can physically link adhesion molecules to the cellular contractile apparatus. Synaptopodin depletion prevents junctional accumulation of α-actinin-4, vinculin, and actin. Knockdown of synaptopodin and α-actinin-4 decreases the strength of cell–cell adhesion, reduces the monolayer permeability barrier, and compromises cellular contractility. Our findings underscore the complexity of junction development and implicate a control process via tension-induced sequential incorporation of junctional components. PMID:26504173

  15. Inter-Cellular Forces Orchestrate Contact Inhibition of Locomotion

    PubMed Central

    Davis, John R.; Luchici, Andrei; Mosis, Fuad; Thackery, James; Salazar, Jesus A.; Mao, Yanlan; Dunn, Graham A.; Betz, Timo; Miodownik, Mark; Stramer, Brian M.

    2015-01-01

    Summary Contact inhibition of locomotion (CIL) is a multifaceted process that causes many cell types to repel each other upon collision. During development, this seemingly uncoordinated reaction is a critical driver of cellular dispersion within embryonic tissues. Here, we show that Drosophila hemocytes require a precisely orchestrated CIL response for their developmental dispersal. Hemocyte collision and subsequent repulsion involves a stereotyped sequence of kinematic stages that are modulated by global changes in cytoskeletal dynamics. Tracking actin retrograde flow within hemocytes in vivo reveals synchronous reorganization of colliding actin networks through engagement of an inter-cellular adhesion. This inter-cellular actin-clutch leads to a subsequent build-up in lamellar tension, triggering the development of a transient stress fiber, which orchestrates cellular repulsion. Our findings reveal that the physical coupling of the flowing actin networks during CIL acts as a mechanotransducer, allowing cells to haptically sense each other and coordinate their behaviors. PMID:25799385

  16. Actin cable dynamics and Rho/Rock orchestrate a polarized cytoskeletal architecture in the early steps of assembling a stratified epithelium.

    PubMed

    Vaezi, Alec; Bauer, Christoph; Vasioukhin, Valeri; Fuchs, Elaine

    2002-09-01

    To enable stratification and barrier function, the epidermis must permit self-renewal while maintaining adhesive connections. By generating K14-GFP-actin mice to monitor actin dynamics in cultured primary keratinocytes, we uncovered a role for the actin cytoskeleton in establishing cellular organization. During epidermal sheet formation, a polarized network of nascent intercellular junctions and radial actin cables assemble in the apical plane of the monolayer. These actin fibers anchor to a central actin-myosin network, creating a tension-based plane of cytoskeleton across the apical surface of the sheet. Movement of the sheet surface relative to its base expands the zone of intercellular overlap, catalyzing new sites for nascent intercellular junctions. This polarized cytoskeleton is dependent upon alpha-catenin, Rho, and Rock, and its regulation may be important for wound healing and/or stratification, where coordinated tissue movements are involved.

  17. Molecular analysis of antigen-independent adhesion forces between T and B lymphocytes.

    PubMed Central

    Amblard, F; Auffray, C; Sekaly, R; Fischer, A

    1994-01-01

    The low-affinity interactions underlying antigen recognition by T-cell receptors (TCRs) are thought to involve antigen-independent adhesion mechanisms. Using a hydrodynamic approach, we found that antigen-independent adhesion occurred between human B cells and resting T cells in a transient and temperature-dependent fashion. The mean cell-cell adhesion force was 0.32 x 10(-9) N and was generated by similar contributions (0.16 x 10(-9) N) of the LFA-1- and CD2-dependent adhesion pathways. After T-cell stimulation with a phorbol ester, the force contributed by LFA-1 was drastically increased, while that of CD2 was unaffected. We propose that weak receptor-mediated adhesion initiates antigen-independent intercellular contacts required for antigen recognition by the TCR and is upregulated following TCR engagement. The method used permits adhesion forces between living cells to be resolved at the molecular level and should prove valuable for the rapid assessment of interaction forces between various types of cells and cell-sized particles. Images PMID:7909604

  18. Leukocyte-inspired biodegradable particles that selectively and avidly adhere to inflamed endothelium in vitro and in vivo

    NASA Astrophysics Data System (ADS)

    Sakhalkar, Harshad S.; Dalal, Milind K.; Salem, Aliasger K.; Ansari, Ramin; Fu, Jie; Kiani, Mohammad F.; Kurjiaka, David T.; Hanes, Justin; Shakesheff, Kevin M.; Goetz, Douglas J.

    2003-12-01

    We exploited leukocyte-endothelial cell adhesion chemistry to generate biodegradable particles that exhibit highly selective accumulation on inflamed endothelium in vitro and in vivo. Leukocyte-endothelial cell adhesive particles exhibit up to 15-fold higher adhesion to inflamed endothelium, relative to noninflamed endothelium, under in vitro flow conditions similar to that present in blood vessels, a 6-fold higher adhesion to cytokine inflamed endothelium relative to non-cytokine-treated endothelium in vivo, and a 10-fold enhancement in adhesion to trauma-induced inflamed endothelium in vivo due to the addition of a targeting ligand. The leukocyte-inspired particles have adhesion efficiencies similar to that of leukocytes and were shown to target each of the major inducible endothelial cell adhesion molecules (E-selectin, P-selectin, vascular cell adhesion molecule 1, and intercellular adhesion molecule 1) that are up-regulated at sites of pathological inflammation. The potential for targeted drug delivery to inflamed endothelium has significant implications for the improved treatment of an array of pathologies, including cardiovascular disease, arthritis, inflammatory bowel disease, and cancer.

  19. Chlorella 11-Peptide Inhibits the Production of Macrophage-Induced Adhesion Molecules and Reduces Endothelin-1 Expression and Endothelial Permeability

    PubMed Central

    Shih, Mei Fen; Chen, Lih Chi; Cherng, Jong Yuh

    2013-01-01

    The inflammation process in large vessels involves the up-regulation of vascular adhesion molecules such as endothelial cell selectin (E-selectin), intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) which are also known as the markers of atherosclerosis. We have reported that Chlorella 11-peptide exhibited effective anti-inflammatory effects. This peptide with an amino sequence Val-Glu-Cys-Tyr-Gly-Pro-Asn-Arg-Pro-Gln-Phe was further examined for its potential in preventing atherosclerosis in this study. In particular, the roles of Chlorella 11-peptide in lowering the production of vascular adhesion molecules, monocyte chemoattractant protein (MCP-1) and expression of endothelin-1 (ET-1) from endothelia (SVEC4-10 cells) were studied. The production of E-selectin, ICAM-1, VCAM-1 and MCP-1 in SVEC4-10 cells was measured with ELISA. The mRNA expression of ET-1 was analyzed by RT-PCR and agarose gel. Results showed that Chlorella 11-peptide significantly suppressed the levels of E-selectin, ICAM, VCAM, MCP-1 as well as ET-1 gene expression. The inhibition of ICAM-1 and VCAM-1 production by Chlorella 11-peptide was reversed in the presence of protein kinase A inhibitor (H89) which suggests that the cAMP pathway was involved in the inhibitory cause of the peptide. In addition, this peptide was shown to reduce the extent of increased intercellular permeability induced by combination of 50% of lipopolysaccharide (LPS)-activated RAW 264.7 cells medium and 50% normal SEVC cell culture medium (referred to as 50% RAW-conditioned medium). These data demonstrate that Chlorella 11-peptide is a promising biomolecule in preventing chronic inflammatory-related vascular diseases. PMID:24129228

  20. New functions for alpha-catenins in health and disease: from cancer to heart regeneration.

    PubMed

    Vite, Alexia; Li, Jifen; Radice, Glenn L

    2015-06-01

    Strong cell-cell adhesion mediated by adherens junctions is dependent on anchoring the transmembrane cadherin molecule to the underlying actin cytoskeleton. To do this, the cadherin cytoplasmic domain interacts with catenin proteins, which include α-catenin that binds directly to filamentous actin. Originally thought to be a static structure, the connection between the cadherin/catenin adhesion complex and the actin cytoskeleton is now considered to be dynamic and responsive to both intercellular and intracellular signals. Alpha-catenins are mechanosensing proteins that undergo conformational change in response to cytoskeletal tension thus modifying the linkage between the cadherin and the actin cytoskeleton. There are three α-catenin isoforms expressed in mouse and human: αE-catenin (CTNNA1), αN-catenin (CTNNA2) and αT-catenin (CTNNA3). This review summarizes recent progress in understanding the in vivo function(s) of α-catenins in tissue morphogenesis, homeostasis and disease. The role of α-catenin in the regulation of cellular proliferation will be discussed in the context of cancer and regeneration.

  1. Molecular basis for disruption of E-cadherin adhesion by botulinum neurotoxin A complex.

    PubMed

    Lee, Kwangkook; Zhong, Xiaofen; Gu, Shenyan; Kruel, Anna Magdalena; Dorner, Martin B; Perry, Kay; Rummel, Andreas; Dong, Min; Jin, Rongsheng

    2014-06-20

    How botulinum neurotoxins (BoNTs) cross the host intestinal epithelial barrier in foodborne botulism is poorly understood. Here, we present the crystal structure of a clostridial hemagglutinin (HA) complex of serotype BoNT/A bound to the cell adhesion protein E-cadherin at 2.4 angstroms. The HA complex recognizes E-cadherin with high specificity involving extensive intermolecular interactions and also binds to carbohydrates on the cell surface. Binding of the HA complex sequesters E-cadherin in the monomeric state, compromising the E-cadherin-mediated intercellular barrier and facilitating paracellular absorption of BoNT/A. We reconstituted the complete 14-subunit BoNT/A complex using recombinantly produced components and demonstrated that abolishing either E-cadherin- or carbohydrate-binding of the HA complex drastically reduces oral toxicity of BoNT/A complex in vivo. Together, these studies establish the molecular mechanism of how HAs contribute to the oral toxicity of BoNT/A. Copyright © 2014, American Association for the Advancement of Science.

  2. Down-regulation of POLYGALACTURONASE1 alters firmness, tensile strength and water loss in apple (Malus x domestica) fruit

    PubMed Central

    2012-01-01

    Background While there is now a significant body of research correlating apple (Malus x domestica) fruit softening with the cell wall hydrolase ENDO-POLYGALACTURONASE1 (PG1), there is currently little knowledge of its physiological effects in planta. This study examined the effect of down regulation of PG1 expression in ‘Royal Gala’ apples, a cultivar that typically has high levels of PG1, and softens during fruit ripening. Results PG1-suppressed ‘Royal Gala’ apples harvested from multiple seasons were firmer than controls after ripening, and intercellular adhesion was higher. Cell wall analyses indicated changes in yield and composition of pectin, and a higher molecular weight distribution of CDTA-soluble pectin. Structural analyses revealed more ruptured cells and free juice in pulled apart sections, suggesting improved integrity of intercellular connections and consequent cell rupture due to failure of the primary cell walls under stress. PG1-suppressed lines also had reduced expansion of cells in the hypodermis of ripe apples, resulting in more densely packed cells in this layer. This change in morphology appears to be linked with reduced transpirational water loss in the fruit. Conclusions These findings confirm PG1’s role in apple fruit softening and suggests that this is achieved in part by reducing cellular adhesion. This is consistent with previous studies carried out in strawberry but not with those performed in tomato. In apple PG1 also appears to influence other fruit texture characters such as juiciness and water loss. PMID:22856470

  3. Effect of tributyltin on mammalian endothelial cell integrity.

    PubMed

    Botelho, G; Bernardini, C; Zannoni, A; Ventrella, V; Bacci, M L; Forni, M

    2015-01-01

    Tributyltin (TBT), is a man-made pollutants, known to accumulate along the food chain, acting as an endocrine disruptor in marine organisms, with toxic and adverse effects in many tissues including vascular system. Based on the absence of specific studies of TBT effects on endothelial cells, we aimed to evaluate the toxicity of TBT on primary culture of porcine aortic endothelial cells (pAECs), pig being an excellent model to study human cardiovascular disease. pAECs were exposed for 24h to TBT (100, 250, 500, 750 and 1000nM) showing a dose dependent decrease in cell viability through both apoptosis and necrosis. Moreover the ability of TBT (100 and 500nM) to influence endothelial gene expression was investigated at 1, 7 and 15h of treatment. Gene expression of tight junction molecules, occludin (OCLN) and tight junction protein-1 (ZO-1) was reduced while monocyte adhesion and adhesion molecules ICAM-1 and VCAM-1 (intercellular adhesion molecule-1 and vascular cell adhesion molecule-1) levels increased significantly at 1h. IL-6 and estrogen receptors 1 and 2 (ESR-1 and ESR-2) mRNAs, after a transient decrease, reached the maximum levels after 15h of exposure. Finally, we demonstrated that TBT altered endothelial functionality greatly increasing monocyte adhesion. These findings indicate that TBT deeply alters endothelial profile, disrupting their structure and interfering with their ability to interact with molecules and other cells. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Extracellular adherence protein (Eap) from Staphylococcus aureus does not function as a superantigen.

    PubMed

    Haggar, A; Flock, J-I; Norrby-Teglund, A

    2010-08-01

    Extracellular adherence protein (Eap) from Staphylococcus aureus has been reported to have strong anti-inflammatory properties, which make Eap a potential anti-inflammatory agent. However, Eap has also been demonstrated to trigger T-cell activation and to share structural homology with superantigens. In this study, we focused on whether Eap fulfilled the definition criteria for a superantigen. We demonstrate that T-cell activation by Eap is dependent on both major histocompatibility complex class II and intercellular adhesion molecule type 1, that cellular processing is required for Eap to elicit T-cell proliferation, and that the kinetics of proliferation resemble the profile of a conventional antigen and not that of a superantigen.

  5. Celecoxib increases lung cancer cell lysis by lymphokine-activated killer cells via upregulation of ICAM-1.

    PubMed

    Schellhorn, Melina; Haustein, Maria; Frank, Marcus; Linnebacher, Michael; Hinz, Burkhard

    2015-11-17

    The antitumorigenic mechanism of the selective cyclooxygenase-2 (COX-2) inhibitor celecoxib is still a matter of debate. Using lung cancer cell lines (A549, H460) and metastatic cells derived from a lung cancer patient, the present study investigates the impact of celecoxib on the expression of intercellular adhesion molecule 1 (ICAM-1) and cancer cell lysis by lymphokine-activated killer (LAK) cells. Celecoxib, but not other structurally related selective COX-2 inhibitors (i.e., etoricoxib, rofecoxib, valdecoxib), was found to cause a substantial upregulation of ICAM-1 protein levels. Likewise, ICAM-1 mRNA expression was increased by celecoxib. Celecoxib enhanced the susceptibility of cancer cells to be lysed by LAK cells with the respective effect being reversed by a neutralizing ICAM-1 antibody. In addition, enhanced killing of celecoxib-treated cancer cells was reversed by preincubation of LAK cells with an antibody to lymphocyte function associated antigen 1 (LFA-1), suggesting intercellular ICAM-1/LFA-1 crosslink as crucial event within this process. Finally, celecoxib elicited no significant increase of LAK cell-mediated lysis of non-tumor bronchial epithelial cells, BEAS-2B, associated with a far less ICAM-1 induction as compared to cancer cells. Altogether, our data demonstrate celecoxib-induced upregulation of ICAM-1 on lung cancer cells to be responsible for intercellular ICAM-1/LFA-1 crosslink that confers increased cancer cell lysis by LAK cells. These findings provide proof for a novel antitumorigenic mechanism of celecoxib.

  6. Celecoxib increases lung cancer cell lysis by lymphokine-activated killer cells via upregulation of ICAM-1

    PubMed Central

    Frank, Marcus; Linnebacher, Michael; Hinz, Burkhard

    2015-01-01

    The antitumorigenic mechanism of the selective cyclooxygenase-2 (COX-2) inhibitor celecoxib is still a matter of debate. Using lung cancer cell lines (A549, H460) and metastatic cells derived from a lung cancer patient, the present study investigates the impact of celecoxib on the expression of intercellular adhesion molecule 1 (ICAM-1) and cancer cell lysis by lymphokine-activated killer (LAK) cells. Celecoxib, but not other structurally related selective COX-2 inhibitors (i.e., etoricoxib, rofecoxib, valdecoxib), was found to cause a substantial upregulation of ICAM-1 protein levels. Likewise, ICAM-1 mRNA expression was increased by celecoxib. Celecoxib enhanced the susceptibility of cancer cells to be lysed by LAK cells with the respective effect being reversed by a neutralizing ICAM-1 antibody. In addition, enhanced killing of celecoxib-treated cancer cells was reversed by preincubation of LAK cells with an antibody to lymphocyte function associated antigen 1 (LFA-1), suggesting intercellular ICAM-1/LFA-1 crosslink as crucial event within this process. Finally, celecoxib elicited no significant increase of LAK cell-mediated lysis of non-tumor bronchial epithelial cells, BEAS-2B, associated with a far less ICAM-1 induction as compared to cancer cells. Altogether, our data demonstrate celecoxib-induced upregulation of ICAM-1 on lung cancer cells to be responsible for intercellular ICAM-1/LFA-1 crosslink that confers increased cancer cell lysis by LAK cells. These findings provide proof for a novel antitumorigenic mechanism of celecoxib. PMID:26513172

  7. ICAM-1 is necessary for epithelial recruitment of gammadelta T cells and efficient corneal wound healing.

    USDA-ARS?s Scientific Manuscript database

    Wound healing and inflammation are both significantly reduced in mice that lack gammadelta T cells. Here, the role of epithelial intercellular adhesion molecule-1 (ICAM-1) in gammadelta T cell migration in corneal wound healing was assessed. Wild-type mice had an approximate fivefold increase in epi...

  8. Herpes simplex virus glycoprotein D relocates nectin-1 from intercellular contacts

    PubMed Central

    Bhargava, Arjun K.; Rothlauf, Paul W.; Krummenacher, Claude

    2016-01-01

    Herpes simplex virus (HSV) uses the cell adhesion molecule nectin-1 as a receptor to enter neurons and epithelial cells. The viral glycoprotein D (gD) is used as a non-canonical ligand for nectin-1. The gD binding site on nectin-1 overlaps with a functional adhesive site involved in nectin-nectin homophilic trans-interaction. Consequently, when nectin-1 is engaged with a cellular ligand at cell junctions, the gD binding site is occupied. Here we report that HSV gD is able to disrupt intercellular homophilic trans-interaction of nectin-1 and induce a rapid redistribution of nectin-1 from cell junctions. This movement does not require the receptor’s interaction with the actin-binding adaptor afadin. Interaction of nectin-1 with afadin is also dispensable for virion surfing along nectin-1-rich filopodia. Cells seeded on gD-coated surfaces also fail to accumulate nectin-1 at cell contact. These data indicate that HSV gD affects nectin-1 locally through direct interaction and more globally through signaling. PMID:27723487

  9. Herpes simplex virus glycoprotein D relocates nectin-1 from intercellular contacts.

    PubMed

    Bhargava, Arjun K; Rothlauf, Paul W; Krummenacher, Claude

    2016-12-01

    Herpes simplex virus (HSV) uses the cell adhesion molecule nectin-1 as a receptor to enter neurons and epithelial cells. The viral glycoprotein D (gD) is used as a non-canonical ligand for nectin-1. The gD binding site on nectin-1 overlaps with a functional adhesive site involved in nectin-nectin homophilic trans-interaction. Consequently, when nectin-1 is engaged with a cellular ligand at cell junctions, the gD binding site is occupied. Here we report that HSV gD is able to disrupt intercellular homophilic trans-interaction of nectin-1 and induce a rapid redistribution of nectin-1 from cell junctions. This movement does not require the receptor's interaction with the actin-binding adaptor afadin. Interaction of nectin-1 with afadin is also dispensable for virion surfing along nectin-1-rich filopodia. Cells seeded on gD-coated surfaces also fail to accumulate nectin-1 at cell contact. These data indicate that HSV gD affects nectin-1 locally through direct interaction and more globally through signaling. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. A genome-wide screen identifies YAP/WBP2 interplay conferring growth advantage on human epidermal stem cells

    PubMed Central

    Walko, Gernot; Woodhouse, Samuel; Pisco, Angela Oliveira; Rognoni, Emanuel; Liakath-Ali, Kifayathullah; Lichtenberger, Beate M.; Mishra, Ajay; Telerman, Stephanie B.; Viswanathan, Priyalakshmi; Logtenberg, Meike; Renz, Lisa M.; Donati, Giacomo; Quist, Sven R.; Watt, Fiona M.

    2017-01-01

    Individual human epidermal cells differ in their self-renewal ability. To uncover the molecular basis for this heterogeneity, we performed genome-wide pooled RNA interference screens and identified genes conferring a clonal growth advantage on normal and neoplastic (cutaneous squamous cell carcinoma, cSCC) human epidermal cells. The Hippo effector YAP was amongst the top positive growth regulators in both screens. By integrating the Hippo network interactome with our data sets, we identify WW-binding protein 2 (WBP2) as an important co-factor of YAP that enhances YAP/TEAD-mediated gene transcription. YAP and WPB2 are upregulated in actively proliferating cells of mouse and human epidermis and cSCC, and downregulated during terminal differentiation. WBP2 deletion in mouse skin results in reduced proliferation in neonatal and wounded adult epidermis. In reconstituted epidermis YAP/WBP2 activity is controlled by intercellular adhesion rather than canonical Hippo signalling. We propose that defective intercellular adhesion contributes to uncontrolled cSCC growth by preventing inhibition of YAP/WBP2. PMID:28332498

  11. Epidermal Expression of Intercellular Adhesion Molecule 1 is Not a Primary Inducer of Cutaneous Inflammation in Transgenic Mice

    NASA Astrophysics Data System (ADS)

    Williams, Ifor R.; Kupper, Thomas S.

    1994-10-01

    Keratinocytes at sites of cutaneous inflammation have increased expression of intercellular adhesion molecule 1 (ICAM-1), a cytokine-inducible adhesion molecule which binds the leukocyte integrins LFA-1 and Mac-1. Transgenic mice were prepared in which the expression of mouse ICAM-1 was targeted to basal keratinocytes by using the human K14 keratin promoter. The level of constitutive expression attained in the transgenic mice exceeded the peak level of ICAM-1 expression induced on nontransgenic mouse keratinocytes in vitro by optimal combinations of interferon γ and tumor necrosis factor α or in vivo by proinflammatory stimuli such as phorbol 12-myristate 13-acetate. In vitro adhesion assays demonstrated that cultured transgenic keratinocytes were superior to normal keratinocytes as a substrate for the LFA-1-dependent binding of mouse T cells, confirming that the transgene-encoded ICAM-1 was expressed in a functional form. However, the high level of constitutive ICAM-1 expression achieved on keratinocytes in vivo in these transgenic mice did not result in additional recruitment of CD45^+ leukocytes into transgenic epidermis, nor did it elicit dermal inflammation. Keratinocyte ICAM-1 expression also did not potentiate contact-hypersensitivity reactions to epicutaneous application of haptens. The absence of a spontaneous phenotype in these transgenic mice was not the result of increased levels of soluble ICAM-1, since serum levels of soluble ICAM-1 were equal in transgenic mice and controls. We conclude that elevated ICAM-1 expression on keratinocytes cannot act independently to influence leukocyte trafficking and elicit cutaneous inflammation.

  12. Active cell-matrix coupling regulates cellular force landscapes of cohesive epithelial monolayers

    NASA Astrophysics Data System (ADS)

    Zhao, Tiankai; Zhang, Yao; Wei, Qiong; Shi, Xuechen; Zhao, Peng; Chen, Long-Qing; Zhang, Sulin

    2018-03-01

    Epithelial cells can assemble into cohesive monolayers with rich morphologies on substrates due to competition between elastic, edge, and interfacial effects. Here we present a molecularly based thermodynamic model, integrating monolayer and substrate elasticity, and force-mediated focal adhesion formation, to elucidate the active biochemical regulation over the cellular force landscapes in cohesive epithelial monolayers, corroborated by microscopy and immunofluorescence studies. The predicted extracellular traction and intercellular tension are both monolayer size and substrate stiffness dependent, suggestive of cross-talks between intercellular and extracellular activities. Our model sets a firm ground toward a versatile computational framework to uncover the molecular origins of morphogenesis and disease in multicellular epithelia.

  13. Loss-of-function mutations in CAST cause peeling skin, leukonychia, acral punctate keratoses, cheilitis, and knuckle pads.

    PubMed

    Lin, Zhimiao; Zhao, Jiahui; Nitoiu, Daniela; Scott, Claire A; Plagnol, Vincent; Smith, Frances J D; Wilson, Neil J; Cole, Christian; Schwartz, Mary E; McLean, W H Irwin; Wang, Huijun; Feng, Cheng; Duo, Lina; Zhou, Eray Yihui; Ren, Yali; Dai, Lanlan; Chen, Yulan; Zhang, Jianguo; Xu, Xun; O'Toole, Edel A; Kelsell, David P; Yang, Yong

    2015-03-05

    Calpastatin is an endogenous specific inhibitor of calpain, a calcium-dependent cysteine protease. Here we show that loss-of-function mutations in calpastatin (CAST) are the genetic causes of an autosomal-recessive condition characterized by generalized peeling skin, leukonychia, acral punctate keratoses, cheilitis, and knuckle pads, which we propose to be given the acronym PLACK syndrome. In affected individuals with PLACK syndrome from three families of different ethnicities, we identified homozygous mutations (c.607dup, c.424A>T, and c.1750delG) in CAST, all of which were predicted to encode truncated proteins (p.Ile203Asnfs∗8, p.Lys142∗, and p.Val584Trpfs∗37). Immunohistochemistry shows that staining of calpastatin is reduced in skin from affected individuals. Transmission electron microscopy revealed widening of intercellular spaces with chromatin condensation and margination in the upper stratum spinosum in lesional skin, suggesting impaired intercellular adhesion as well as keratinocyte apoptosis. A significant increase of apoptotic keratinocytes was also observed in TUNEL assays. In vitro studies utilizing siRNA-mediated CAST knockdown revealed a role for calpastatin in keratinocyte adhesion. In summary, we describe PLACK syndrome, as a clinical entity of defective epidermal adhesion, caused by loss-of-function mutations in CAST. Copyright © 2015 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  14. A Functional Analysis on the Interspecies Interaction between Mouse LFA-1 and Human Intercellular Adhesion Molecule-1 at the Cell Level

    PubMed Central

    Núñez, David; Comas, Laura; Lanuza, Pilar M.; Sánchez-Martinez, Diego; Pérez-Hernández, Marta; Catalán, Elena; Domingo, María Pilar; Velázquez-Campoy, Adrián; Pardo, Julián; Gálvez, Eva M.

    2017-01-01

    The interaction between intercellular adhesion molecules (ICAM) and the integrin leukocyte function-associated antigen-1 (LFA-1) is crucial for the regulation of several physiological and pathophysiological processes like cell-mediated elimination of tumor or virus infected cells, cancer metastasis, or inflammatory and autoimmune processes. Using purified proteins it was reported a species restriction for the interaction of ICAM-1 and LFA-1, being mouse ICAM-1 able to interact with human LFA-1 but not human ICAM-1 with mouse LFA-1. However, in vivo results employing tumor cells transfected with human ICAM-1 suggest that functionally mouse LFA-1 can recognize human ICAM-1. In order to clarify the interspecies cross-reactivity of the ICAM-1/LFA-1 interaction, we have performed functional studies analyzing the ability of human soluble ICAM-1 and human/mouse LFA-1 derived peptides to inhibit cell aggregation and adhesion as well as cell-mediated cytotoxicity in both mouse and human systems. In parallel, the affinity of the interaction between mouse LFA-1-derived peptides and human ICAM-1 was determined by calorimetry assays. According to the results obtained, it seems that human ICAM-1 is able to interact with mouse LFA-1 on intact cells, which should be taking into account when using humanized mice and xenograft models for the study of immune-related processes. PMID:29312326

  15. A Functional Analysis on the Interspecies Interaction between Mouse LFA-1 and Human Intercellular Adhesion Molecule-1 at the Cell Level.

    PubMed

    Núñez, David; Comas, Laura; Lanuza, Pilar M; Sánchez-Martinez, Diego; Pérez-Hernández, Marta; Catalán, Elena; Domingo, María Pilar; Velázquez-Campoy, Adrián; Pardo, Julián; Gálvez, Eva M

    2017-01-01

    The interaction between intercellular adhesion molecules (ICAM) and the integrin leukocyte function-associated antigen-1 (LFA-1) is crucial for the regulation of several physiological and pathophysiological processes like cell-mediated elimination of tumor or virus infected cells, cancer metastasis, or inflammatory and autoimmune processes. Using purified proteins it was reported a species restriction for the interaction of ICAM-1 and LFA-1, being mouse ICAM-1 able to interact with human LFA-1 but not human ICAM-1 with mouse LFA-1. However, in vivo results employing tumor cells transfected with human ICAM-1 suggest that functionally mouse LFA-1 can recognize human ICAM-1. In order to clarify the interspecies cross-reactivity of the ICAM-1/LFA-1 interaction, we have performed functional studies analyzing the ability of human soluble ICAM-1 and human/mouse LFA-1 derived peptides to inhibit cell aggregation and adhesion as well as cell-mediated cytotoxicity in both mouse and human systems. In parallel, the affinity of the interaction between mouse LFA-1-derived peptides and human ICAM-1 was determined by calorimetry assays. According to the results obtained, it seems that human ICAM-1 is able to interact with mouse LFA-1 on intact cells, which should be taking into account when using humanized mice and xenograft models for the study of immune-related processes.

  16. Numb controls E-cadherin endocytosis through p120 catenin with aPKC

    PubMed Central

    Sato, Kazuhide; Watanabe, Takashi; Wang, Shujie; Kakeno, Mai; Matsuzawa, Kenji; Matsui, Toshinori; Yokoi, Keiko; Murase, Kiyoko; Sugiyama, Ikuko; Ozawa, Masayuki; Kaibuchi, Kozo

    2011-01-01

    Cadherin trafficking controls tissue morphogenesis and cell polarity. The endocytic adaptor Numb participates in apicobasal polarity by acting on intercellular adhesions in epithelial cells. However, it remains largely unknown how Numb controls cadherin-based adhesion. Here, we found that Numb directly interacted with p120 catenin (p120), which is known to interact with E-cadherin and prevent its internalization. Numb accumulated at intercellular adhesion sites and the apical membrane in epithelial cells. Depletion of Numb impaired E-cadherin internalization, whereas depletion of p120 accelerated internalization. Expression of the Numb-binding fragment of p120 inhibited E-cadherin internalization in a dominant-negative fashion, indicating that Numb interacts with the E-cadherin/p120 complex and promotes E-cadherin endocytosis. Impairment of Numb induced mislocalization of E-cadherin from the lateral membrane to the apical membrane. Atypical protein kinase C (aPKC), a member of the PAR complex, phosphorylated Numb and inhibited its association with p120 and α-adaptin. Depletion or inhibition of aPKC accelerated E-cadherin internalization. Wild-type Numb restored E-cadherin internalization in the Numb-depleted cells, whereas a phosphomimetic mutant or a mutant with defective α-adaptin-binding ability did not restore the internalization. Thus, we propose that aPKC phosphorylates Numb to prevent its binding to p120 and α-adaptin, thereby attenuating E-cadherin endocytosis to maintain apicobasal polarity. PMID:21775625

  17. Gastrin-releasing peptide induces monocyte adhesion to vascular endothelium by upregulating endothelial adhesion molecules

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Mi-Kyoung; Park, Hyun-Joo; Department of Dental Pharmacology, BK21 PLUS Project, School of Dentistry, Pusan National University, Yangsan 626-870

    Gastrin-releasing peptide (GRP) is a neuropeptide that plays roles in various pathophysiological conditions including inflammatory diseases in peripheral tissues; however, little is known about whether GRP can directly regulate endothelial inflammatory processes. In this study, we showed that GRP promotes the adhesion of leukocytes to human umbilical vein endothelial cells (HUVECs) and the aortic endothelium. GRP increased the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) by activating nuclear factor-κB (NF-κB) in endothelial cells. In addition, GRP activated extracellular signal-regulated kinase 1/2 (ERK1/2), p38MAPK, and AKT, and the inhibition of these signaling pathways significantly reduced GRP-inducedmore » monocyte adhesion to the endothelium. Overall, our results suggested that GRP may cause endothelial dysfunction, which could be of particular relevance in the development of vascular inflammatory disorders. - Highlights: • GRP induces adhesion of monocytes to vascular endothelium. • GRP increases the expression of endothelial adhesion molecules through the activation of NF-κB. • ERK1/2, p38MAPK, and Akt pathways are involved in the GRP-induced leukocyte adhesiveness to endothelium.« less

  18. Inter-cellular forces orchestrate contact inhibition of locomotion.

    PubMed

    Davis, John R; Luchici, Andrei; Mosis, Fuad; Thackery, James; Salazar, Jesus A; Mao, Yanlan; Dunn, Graham A; Betz, Timo; Miodownik, Mark; Stramer, Brian M

    2015-04-09

    Contact inhibition of locomotion (CIL) is a multifaceted process that causes many cell types to repel each other upon collision. During development, this seemingly uncoordinated reaction is a critical driver of cellular dispersion within embryonic tissues. Here, we show that Drosophila hemocytes require a precisely orchestrated CIL response for their developmental dispersal. Hemocyte collision and subsequent repulsion involves a stereotyped sequence of kinematic stages that are modulated by global changes in cytoskeletal dynamics. Tracking actin retrograde flow within hemocytes in vivo reveals synchronous reorganization of colliding actin networks through engagement of an inter-cellular adhesion. This inter-cellular actin-clutch leads to a subsequent build-up in lamellar tension, triggering the development of a transient stress fiber, which orchestrates cellular repulsion. Our findings reveal that the physical coupling of the flowing actin networks during CIL acts as a mechanotransducer, allowing cells to haptically sense each other and coordinate their behaviors. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  19. Piperidine carboxylic acid derivatives of 10H-pyrazino[2,3-b][1,4]benzothiazine as orally-active adhesion molecule inhibitors.

    PubMed

    Kaneko, Toshihiko; Clark, Richard S J; Ohi, Norihito; Ozaki, Fumihiro; Kawahara, Tetsuya; Kamada, Atsushi; Okano, Kazuo; Yokohama, Hiromitsu; Ohkuro, Masayoshi; Muramoto, Kenzo; Takenaka, Osamu; Kobayashi, Seiichi

    2004-06-01

    Novel piperidine carboxylic acid derivatives of 10H-pyrazino[2,3-b][1,4]benzothiazine were prepared and evaluated for their inhibitory activity on the upregulation of adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1). Replacement of the methanesulfonyl group on the piperidine ring of previously prepared derivatives with a carboxylic acid-containing moiety resulted in a number of potent adhesion molecule inhibitors. Of these, (anti) [3-(10H-pyrazino[2,3-b][1,4]benzothiazin-8-yl)methyl-3-azabicyclo[3.3.1]non-9-yl]acetic acid 2q (ER-49890), showed the most potent oral inhibitory activities against neutrophil migration in an interleukin-1 (IL-1) induced paw inflammation model using mice, and leukocyte accumulation in a carrageenan pleurisy model in the rat, and therapeutic effect on collagen-induced arthritis in rats.

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang Huayan; Yu Junping; Fu Guo

    The interaction between integrin macrophage differentiation antigen associated with complement three receptor function (Mac-1) and intercellular adhesion molecule-1 (ICAM-1), which is controlled tightly by the ligand-binding activity of Mac-1, is central to the regulation of neutrophil adhesion in host defense. Several 'inside-out' signals and extracellular metal ions or antibodies have been found to activate Mac-1, resulting in an increased adhesiveness of Mac-1 to its ligands. However, the molecular basis for Mac-1 activation is not well understood yet. In this work, we have carried out a single-molecule study of Mac-1/ICAM-1 interaction force in living cells by atomic force microscopy (AFM). Ourmore » results showed that the binding probability and adhesion force of Mac-1 with ICAM-1 increased upon Mac-1 activation. Moreover, by comparing the dynamic force spectra of different Mac-1 mutants, we expected that Mac-1 activation is governed by the downward movement of its {alpha}7 helix.« less

  1. Inhibition of TNFα-induced adhesion molecule expression by (Z)-(S)-9-octadecenamide, N-(2-hydroxyethyl,1-methyl).

    PubMed

    Chen, Caixia; Jin, Xin; Meng, Xianglan; Zheng, Chengwei; Shen, Yanhui; Wang, Yiqing

    2011-06-25

    Inflammation is a primary event in atherogenesis. Oleoylethanolamide (OEA), a naturally occurring fatty-acid ethanolamide, lowers lipid levels in liver and blood through activation of the nuclear receptor, peroxisome proliferator-activated receptor-alpha (PPARα). We designed and synthesized (Z)-(S)-9-octadecenamide, N-(2-hydroxyethyl, 1-methyl) (OPA), an OEA analog. The present study investigated the effect of OPA on the expression of adhesion molecules in human umbilical vein endothelial cells (HUVEC). OPA inhibited expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) stimulated by Tumor Necrosis Factor-α (TNF-α) via activation of PPARα. This inhibition of VCAM-1 and ICAM-1 expression decreased adhesion of monocyte-like cells to stimulated endothelial cells. These results demonstrate that OPA may have anti-inflammatory properties. Our results thus provide new insights into possible future therapeutic approaches to the treatment of atherosclerosis. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Adhesion signaling promotes protease‑driven polyploidization of glioblastoma cells.

    PubMed

    Mercapide, Javier; Lorico, Aurelio

    2014-11-01

    An increase in ploidy (polyploidization) causes genomic instability in cancer. However, the determinants for the increased DNA content of cancer cells have not yet been fully elucidated. In the present study, we investigated whether adhesion induces polyploidization in human U87MG glioblastoma cells. For this purpose, we employed expression vectors that reported transcriptional activation by signaling networks implicated in cancer. Signaling activation induced by intercellular integrin binding elicited both extracellular signal‑regulated kinase (ERK) and Notch target transcription. Upon the prolonged activation of both ERK and Notch target transcription induced by integrin binding to adhesion protein, cell cultures accumulated polyploid cells, as determined by cell DNA content distribution analysis and the quantification of polynucleated cells. This linked the transcriptional activation induced by integrin adhesion to the increased frequency of polyploidization. Accordingly, the inhibition of signaling decreased the extent of polyploidization mediated by protease‑driven intracellular invasion. Therefore, the findings of this study indicate that integrin adhesion induces polyploidization through the stimulation of glioblastoma cell invasiveness.

  3. A composite model of the human postcapillary venule for investigation of microvascular leukocyte recruitment

    PubMed Central

    Lauridsen, Holly M.; Pober, Jordan S.; Gonzalez, Anjelica L.

    2014-01-01

    Neutrophil extravasation occurs across postcapillary venules, structures composed of endothelial cells (ECs), pericytes (PCs), and basement membrane (BM). We constructed composite models of the human postcapillary venule, combining ECs with PCs or PC-deposited BM, to better study this process. Quiescent and tumor necrosis factor α (TNF-α)-activated composites demonstrated in situ-like expression of cadherins, E-selectin, intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), platelet-endothelial cell adhesion molecule 1 (PECAM-1), CD99, and interleukin 8 (IL-8). After TNF-α activation, the ECs supported greater neutrophil adhesion (66.1 vs. 23.7% of input cells) and transmigration (35.1 vs. 7.20% of input cells) than did the PCs, but the composites behaved comparably (no significant difference) to ECs in both assays. TNF-α-activated EC-conditioned medium (CM) increased transmigration across the PCs, whereas TNF-α-activated PC-CM decreased transmigration across the ECs, and culturing on PC-derived BM decreased both adhesion to and transmigration across the ECs. Anti-very late antigen 4 (VLA-4; on neutrophils) inhibited adhesion to TNF-α-activated composites, but not to ECs alone. Anti-CD99 (expressed on all 3 cell types) inhibited transmigration across the composites (14.5% of control) more than across the ECs (39.0% of control), and venular shear stress reduced transmigration across the ECs (17.3% of static) more than across the composites (36.7% of static). These results provide proof of concept that our composite human EC/PC/BM venular construct can reveal new interactions in the inflammatory cascade.—Lauridsen, H. M., Pober, J. S., Gonzalez, A. L. A composite model of the human postcapillary venule for investigation of microvascular leukocyte recruitment. PMID:24297702

  4. The Crystal Structure of Coxsackievirus A21 and Its Interaction with ICAM-1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xiao, Chuan; Bator-Kelly, Carol M.; Rieder, Elizabeth

    2010-11-30

    CVA21 and polioviruses both belong to the Enterovirus genus in the family of Picornaviridae, whereas rhinoviruses form a distinct picornavirus genus. Nevertheless, CVA21 and the major group of human rhinoviruses recognize intercellular adhesion molecule-1 (ICAM-1) as their cellular receptor, whereas polioviruses use poliovirus receptor. The crystal structure of CVA21 has been determined to 3.2 {angstrom} resolution. Its structure has greater similarity to poliovirus structures than to other known picornavirus structures. Cryo-electron microscopy (cryo-EM) was used to determine an 8.0 {angstrom} resolution structure of CVA21 complexed with an ICAM-1 variant, ICAM-1{sup Kilifi}. The cryo-EM map was fitted with the crystal structuresmore » of ICAM-1 and CVA21. Significant differences in the structure of CVA21 with respect to the poliovirus structures account for the inability of ICAM-1 to bind polioviruses. The interface between CVA21 and ICAM-1 has shape and electrostatic complementarity with many residues being conserved among those CVAs that bind ICAM-1.« less

  5. The cell clone ecology hypothesis and the cell fusion model of cancer progression and metastasis (II): three pathways for spontaneous cell-cell fusion and escape from the intercellular matrix.

    PubMed

    Parris, George

    2006-01-01

    The two-stage initiation-progression model of cancer is widely accepted. Initiation appears to result most often from accumulation of damage to the DNA expressed as multiple mutations in the phenotype. Unsymmetrical chromosome segregation during mitosis of normal or mutated cells produces aneuploid cells and also contributes to the evolution of neoplasia. However, it has been pointed out (Parris GE. Med Hypotheses 2005;65:993-4 and 2006;66:76-83) that DNA damage and loss of chromosomes are much more likely to lead the mutant clones of cells to extinction than to successful expansion (e.g., an example of Muller's Ratchet). It was argued that aneuploid neoplasia represent new parasite species that successfully evolve to devour their hosts by incorporating sex-like redistribution of chromosomes through spontaneous or virus-catalyzed cell-cell fusion into their life-cycle. Spontaneous cell-cell fusion is generally blocked by the intercellular matrix to which the cells are bound via surface adhesion molecules (frequently glycoproteins, e.g., CD44). In order for progression of matrix-contained neoplasia toward clinically significant cancer to occur, the parasite cells must escape from the matrix and fuse. Release from the matrix also allows the parasite cells to invade adjacent tissues and metastasize to remote locations. Both invasion and metastasis likely involve fusion of the migrating parasite cells with fusion-prone blast cells. There are at least three pathways through which parasite cells can be liberated from the confining matrix: (i) Their adhesion molecules may be modified (e.g., by hyper-glycosylation) so that they can no longer grip the matrix. (ii) Their adhesion molecules or matrix may be saturated with other ligands (e.g., polyamines). (iii) Their adhesion molecules may be cleaved from the cell surface or the matrix itself may be cleaved (e.g., by MMPs or ADAMs). It is hypothesized that mobilization of parasite cells and cell-cell fusion go hand-in-hand in the progression of neoplasia to clinically significant cancer through invasion and metastasis. The latency between tumor recognition and exposure to mutagens and the increased incidence of cancer with age can probably be related to slow breakdown of the intercellular matrix that provides a barrier to cell-cell fusion.

  6. Mammary collective cell migration involves transient loss of epithelial features and individual cell migration within the epithelium

    PubMed Central

    Ewald, Andrew J.; Huebner, Robert J.; Palsdottir, Hildur; Lee, Jessie K.; Perez, Melissa J.; Jorgens, Danielle M.; Tauscher, Andrew N.; Cheung, Kevin J.; Werb, Zena; Auer, Manfred

    2012-01-01

    Normal mammary morphogenesis involves transitions between simple and multilayered epithelial organizations. We used electron microscopy and molecular markers to determine whether intercellular junctions and apico-basal polarity were maintained in the multilayered epithelium. We found that multilayered elongating ducts had polarized apical and basal tissue surfaces both in three-dimensional culture and in vivo. However, individual cells were only polarized on surfaces in contact with the lumen or extracellular matrix. The basolateral marker scribble and the apical marker atypical protein kinase C zeta localized to all interior cell membranes, whereas PAR3 displayed a cytoplasmic localization, suggesting that the apico-basal polarity was incomplete. Despite membrane localization of E-cadherin and β-catenin, we did not observe a defined zonula adherens connecting interior cells. Instead, interior cells were connected through desmosomes and exhibited complex interdigitating membrane protrusions. Single-cell labeling revealed that individual cells were both protrusive and migratory within the epithelial multilayer. Inhibition of Rho kinase (ROCK) further reduced intercellular adhesion on apical and lateral surfaces but did not disrupt basal tissue organization. Following morphogenesis, segregated membrane domains were re-established and junctional complexes re-formed. We observed similar epithelial organization during mammary morphogenesis in organotypic culture and in vivo. We conclude that mammary epithelial morphogenesis involves a reversible, spatially limited, reduction in polarity and intercellular junctions and active individualistic cell migration. Our data suggest that reductions in polarity and adhesion during breast cancer progression might reflect partial recapitulation of a normal developmental program. PMID:22344263

  7. Changes in the vascular cell adhesion molecule-1, intercellular adhesion molecule-1 and c-reactive protein following administration of aqueous extract of piper sarmentosum on experimental rabbits fed with cholesterol diet

    PubMed Central

    2011-01-01

    Background Inflammation process plays an important role in the development of atherosclerosis. Hypercholesterolemia is one of the major risk factors for atherosclerosis. The present study aimed to evaluate the effect of aqueous extract of Piper sarmentosum (P.s) on inflammatory markers like vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and C-reactive protein (CRP). Methods Forty two male New Zealand white rabbits were divided equally into seven groups; (i) C- control group fed normal rabbit chow (ii) CH- cholesterol diet (1%cholesterol) (iii) X1- 1% cholesterol with water extract of P.s (62.5 mg/kg) (iv) X2- 1% cholesterol with water extract of P.s (125 mg/kg (v) X3- 1% cholesterol with water extract of P.s (250 mg/kg) (vi) X4- 1% cholesterol with water extract of P.s (500 mg/kg) and (vii) SMV group fed with 1% cholesterol supplemented with simvistatin drug (1.2 mg/kg). All animals were treated for 10 weeks. Blood serum was taken for observing the inflammatory markers at the beginning and end of the experiment. Results Rabbits fed with 1% cholesterol diet (CH) showed significant increase in the level of VCAM-1, ICAM-1 and CRP compared to the C group. The levels of VCAM-1, ICAM-1 and CRP in the 1% cholesterol group and supplemented with P.s (500 mg/kg) were significantly reduced compared to the cholesterol group. Similar results were also reported with simvistatin group. Conclusion These results suggest that the supplementation of Piper sarmentosum extract could inhibit inflammatory markers which in turn could prevent atherosclerosis. PMID:21214952

  8. Renoprotective effects of berberine and its potential effect on the expression of β-arrestins and intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 in streptozocin-diabetic nephropathy rats.

    PubMed

    Tang, Li-Qin; Ni, Wei-Jian; Cai, Ming; Ding, Hai-Hua; Liu, Sheng; Zhang, Shan-Tang

    2016-09-01

    Berberine has been shown to exert protective effects against diabetic nephropathy (DN), but the mechanisms involved have not been fully characterized. The aim of the present study was to explore the effects of berberine on the expression of β-arrestins, intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in DN rat kidneys and investigate the underlying molecular mechanisms. To create the DN model, rats fed a high-fat and high-glucose diet were injected with a single dose of streptozotocin (35 mg/kg, i.p.). Then, DN rats were either treated or not with berberine (50, 100, 200 mg/kg per day, i.g., 8 weeks). Periodic acid-Schiff staining was used to evaluate renal histopathological changes. Renal tissue levels of β-arrestin 1 and β-arrestin 2 were determined by Western blot analysis, whereas immunohistochemistry was used to determine renal ICAM-1 and VCAM-1 levels. Berberine (100, 200 mg/kg) ameliorated the histopathological changes in the diabetic kidney. Western blot analysis revealed significant increases in ICAM-1 and VCAM-1 levels in the kidneys of DN rats, which were reversed by treatment with 100 and 200 mg/kg berberine. In addition, berberine treatment (50, 100, 200 mg/kg) increased diabetic-induced decreases in β-arrestin 1 and β-arrestin 2. Berberine exhibited renoprotective effects in DN rats. The underlying molecular mechanisms may be associated with changes in the levels and regulation of β-arrestin expression, as well as ICAM-1 and VCAM-1 levels in the rat kidney. © 2015 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.

  9. Reduced Expression of Adipose Triglyceride Lipase Enhances Tumor Necrosis Factor α-induced Intercellular Adhesion Molecule-1 Expression in Human Aortic Endothelial Cells via Protein Kinase C-dependent Activation of Nuclear Factor-κB*

    PubMed Central

    Inoue, Tomoaki; Kobayashi, Kunihisa; Inoguchi, Toyoshi; Sonoda, Noriyuki; Fujii, Masakazu; Maeda, Yasutaka; Fujimura, Yoshinori; Miura, Daisuke; Hirano, Ken-ichi; Takayanagi, Ryoichi

    2011-01-01

    We examined the effects of adipose triglyceride lipase (ATGL) on the initiation of atherosclerosis. ATGL was recently identified as a rate-limiting triglyceride (TG) lipase. Mutations in the human ATGL gene are associated with neutral lipid storage disease with myopathy, a rare genetic disease characterized by excessive accumulation of TG in multiple tissues. The cardiac phenotype, known as triglyceride deposit cardiomyovasculopathy, shows massive TG accumulation in both coronary atherosclerotic lesions and the myocardium. Recent reports show that myocardial triglyceride content is significantly higher in patients with prediabetes or diabetes and that ATGL expression is decreased in the obese insulin-resistant state. Therefore, we investigated the effect of decreased ATGL activity on the development of atherosclerosis using human aortic endothelial cells. We found that ATGL knockdown enhanced monocyte adhesion via increased expression of TNFα-induced intercellular adhesion molecule-1 (ICAM-1). Next, we determined the pathways (MAPK, PKC, or NFκB) involved in ICAM-1 up-regulation induced by ATGL knockdown. Both phosphorylation of PKC and degradation of IκBα were increased in ATGL knockdown human aortic endothelial cells. In addition, intracellular diacylglycerol levels and free fatty acid uptake via CD36 were significantly increased in these cells. Inhibition of the PKC pathway using calphostin C and GF109203X suppressed TNFα-induced ICAM-1 expression. In conclusion, we showed that ATGL knockdown increased monocyte adhesion to the endothelium through enhanced TNFα-induced ICAM-1 expression via activation of NFκB and PKC. These results suggest that reduced ATGL expression may influence the atherogenic process in neutral lipid storage diseases and in the insulin-resistant state. PMID:21828047

  10. Structural basis for PECAM-1 homophilic binding

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Paddock, C.; Zhou, D.; Lertkiatmongkol, P.

    2015-12-23

    Platelet endothelial cell adhesion molecule-1 (PECAM-1) is a 130-kDa member of the immunoglobulin gene superfamily (IgSF) that is present on the surface of circulating platelets and leukocytes, and highly expressed at the junctions of confluent endothelial cell monolayers. PECAM-1–mediated homophilic interactions, known to be mediated by its 2 amino-terminal immunoglobulin homology domains, are essential for concentrating PECAM-1 at endothelial cell intercellular junctions, where it functions to facilitate diapedesis, maintain vascular integrity, and transmit survival signals into the cell. Given the importance of PECAM-1–mediated homophilic interactions in mediating each of these cell physiological events, and to reveal the nature and orientationmore » of the PECAM-1–PECAM-1 homophilic-binding interface, we undertook studies aimed at determining the crystal structure of the PECAM-1 homophilic-binding domain, which is composed of amino-terminal immunoglobulin homology domains 1 and 2 (IgD1 and IgD2). The crystal structure revealed that both IgD1 and IgD2 exhibit a classical IgSF fold, having a β-sandwich topology formed by 2 sheets of antiparallel β strands stabilized by the hallmark disulfide bond between the B and F strands. Interestingly, despite previous assignment to the C2 class of immunoglobulin-like domains, the structure of IgD1 reveals that it actually belongs to the I2 set of IgSF folds. Both IgD1 and IgD2 participate importantly in the formation of the trans homophilic-binding interface, with a total buried interface area of >2300 Å 2. These and other unique structural features of PECAM-1 allow for the development of an atomic-level model of the interactions that PECAM-1 forms during assembly of endothelial cell intercellular junctions.« less

  11. Loss of intercellular adhesion activates a transition from low- to high-grade human squamous cell carcinoma.

    PubMed

    Margulis, Alexander; Zhang, Weitian; Alt-Holland, Addy; Pawagi, Sujata; Prabhu, Padmaja; Cao, Jian; Zucker, Stanley; Pfeiffer, Laurence; Garfield, Jacqueline; Fusenig, Norbert E; Garlick, Jonathan A

    2006-02-15

    The relationship between loss of intercellular adhesion and the biologic properties of human squamous cell carcinoma is not well understood. We investigated how abrogation of E-cadherin-mediated adhesion influenced the behavior and phenotype of squamous cell carcinoma in 3D human tissues. Cell-cell adhesion was disrupted in early-stage epithelial tumor cells (HaCaT-II-4) through expression of a dominant-negative form of E-cadherin (H-2Kd-Ecad). Three-dimensional human tissue constructs harboring either H-2Kd-Ecad-expressing or control II-4 cells (pBabe, H-2Kd-EcadDeltaC25) were cultured at an air-liquid interface for 8 days and transplanted to nude mice; tumor phenotype was analyzed 2 days and 2 and 4 weeks later. H-2Kd-Ecad-expressing tumors demonstrated a switch to a high-grade aggressive tumor phenotype characterized by poorly differentiated tumor cells that infiltrated throughout the stroma. This high-grade carcinoma revealed elevated cell proliferation in a random pattern, loss of keratin 1 and diffuse deposition of laminin 5 gamma2 chain. When II-4 cell variants were seeded into type I collagen gels as an in vitro assay for cell migration, we found that only E-cadherin-deficient cells detached, migrated as single cells and expressed N-cadherin. Function-blocking studies demonstrated that this migration was matrix metalloproteinase-dependent, as GM-6001 and TIMP-2, but not TIMP-1, could block migration. Gene expression profiles revealed that E-cadherin-deficient II-4 cells demonstrated increased expression of proteases and cell-cell and cell-matrix proteins. These findings showed that loss of E-cadherin-mediated adhesion plays a causal role in the transition from low- to high-grade squamous cell carcinomas and that the absence of E-cadherin is an important prognostic marker in the progression of this disease.

  12. Local adherent technique for transplanting mesenchymal stem cells as a potential treatment of cartilage defect.

    PubMed

    Koga, Hideyuki; Shimaya, Masayuki; Muneta, Takeshi; Nimura, Akimoto; Morito, Toshiyuki; Hayashi, Masaya; Suzuki, Shiro; Ju, Young-Jin; Mochizuki, Tomoyuki; Sekiya, Ichiro

    2008-01-01

    Current cell therapy for cartilage regeneration requires invasive procedures, periosteal coverage and scaffold use. We have developed a novel transplantation method with synovial mesenchymal stem cells (MSCs) to adhere to the cartilage defect. For ex vivo analysis in rabbits, the cartilage defect was faced upward, filled with synovial MSC suspension, and held stationary for 2.5 to 15 minutes. The number of attached cells was examined. For in vivo analysis in rabbits, an autologous synovial MSC suspension was placed on the cartilage defect, and the position was maintained for 10 minutes to adhere the cells to the defect. For the control, either the same cell suspension was injected intra-articularly or the defects were left empty. The three groups were compared macroscopically and histologically. For ex vivo analysis in humans, in addition to the similar experiment in rabbits, the expression and effects of neutralizing antibodies for adhesion molecules were examined. Ex vivo analysis in rabbits demonstrated that the number of attached cells increased in a time-dependent manner, and more than 60% of cells attached within 10 minutes. The in vivo study showed that a large number of transplanted synovial MSCs attached to the defect at 1 day, and the cartilage defect improved at 24 weeks. The histological score was consistently better than the scores of the two control groups (same cell suspension injected intra-articularly or defects left empty) at 4, 12, and 24 weeks. Ex vivo analysis in humans provided similar results to those in rabbits. Intercellular adhesion molecule 1-positive cells increased between 1 minute and 10 minutes, and neutralizing antibodies for intercellular adhesion molecule 1, vascular cell adhesion molecule 1 and activated leukocyte-cell adhesion molecule inhibited the attachment. Placing MSC suspension on the cartilage defect for 10 minutes resulted in adherence of >60% of synovial MSCs to the defect, and promoted cartilage regeneration. This adherent method makes it possible to adhere MSCs with low invasion, without periosteal coverage, and without a scaffold.

  13. Circulating sICAM-1 and sE-Selectin as biomarker of infection and prognosis in patients with systemic inflammatory response syndrome.

    PubMed

    de Pablo, Raúl; Monserrat, Jorge; Reyes, Eduardo; Díaz, David; Rodríguez-Zapata, Manuel; de la Hera, Antonio; Prieto, Alfredo; Álvarez-Mon, Melchor

    2013-03-01

    Vascular endothelium activation is a key pathogenic step in systemic inflammatory response syndrome (SIRS) that can be triggered by both microbial and sterile proinflammatory stimuli. The relevance of soluble adhesion molecules as clinical biomarkers to discriminate between infectious and non-infectious SIRS, and the individual patient prognosis, has not been established. We prospectively measured by sandwich ELISA, serum levels of soluble E-Selectin (sE-Selectin), soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular adhesion molecule-1 (sICAM-1) and soluble intercellular adhesion molecule-2 (sICAM-2) at ICU admission and at days 3, 7, 14 and 28 in patients with sepsis and at days 3 and 7 in patients with non-infectious SIRS. At ICU admission, sE-Selectin, sVCAM-1 and sICAM-1 in patients with infectious SIRS were significantly higher than those found in patients with non-infectious SIRS. ROC analysis revealed that the AUC for infection identification was best for sICAM-1 (0.900±0.041; 95% CI 0.819-0.981; p<0.0001). Moreover, multivariate analysis showed that 4 variables were significantly and independently associated with mortality at 28 days: male gender (OR 15.90; 95% CI, 2.54-99.32), MODS score (OR 5.60; 95% CI, 1.67-18.74), circulating sE-Selectin levels (OR 4.81; 95% CI, 1.34-17.19) and sVCAM-1 concentrations (OR 4.80; 95% CI, 1.34-17.14). Patients with SIRS secondary to infectious or non-infectious etiology show distinctive patterns of disturbance in serum soluble adhesion molecules. Serum ICAM-1 is a reliable biomarker for classifying patients with infectious SIRS from those with non-infectious SIRS. In addition, soluble E-Selectin is a prognostic biomarker with higher levels in patients with SIRS and fatal outcome. Copyright © 2012 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

  14. Role of the teneurins, teneurin C-terminal associated peptides (TCAP) in reproduction: clinical perspectives.

    PubMed

    Lovejoy, David A; Pavlović, Téa

    2015-11-01

    In humans, the teneurin gene family consists of four highly conserved paralogous genes that are the result of early vertebrate gene duplications arising from a gene introduced into multicellular organisms from a bacterial ancestor. In vertebrates and humans, the teneurins have become integrated into a number of critical physiological systems including several aspects of reproductive physiology. Structurally complex, these genes possess a sequence in their terminal exon that encodes for a bioactive peptide sequence termed the 'teneurin C-terminal associated peptide' (TCAP). The teneurin/TCAP protein forms an intercellular adhesive unit with its receptor, latrophilin, an Adhesion family G-protein coupled receptor. It is present in numerous cell types and has been implicated in gamete migration and gonadal morphology. Moreover, TCAP is highly effective at reducing the corticotropin-releasing factor (CRF) stress response. As a result, TCAP may also play a role in regulating the stress-associated inhibition of reproduction. In addition, the teneurins and TCAP have been implicated in tumorigenesis associated with reproductive tissues. Therefore, the teneurin/TCAP system may offer clinicians a novel biomarker system upon which to diagnose some reproductive pathologies.

  15. Protopine inhibits heterotypic cell adhesion in MDA-MB-231 cells through down-regulation of multi-adhesive factors.

    PubMed

    He, Kai; Gao, Jian-Li

    2014-01-01

    A Chinese herb Corydalis yanhusuo W.T. Wang that showed anticancer and anti-angiogenesis effects in our previous studies was presented for further studies. In the present study, we studied the anticancer proliferation and adhesion effects of five alkaloids which were isolated from Corydalis yanhusuo. MTT dose response curves, cell migration assay, cell invasion assay, as well as three types of cell adhesive assay were performed on MDA-MB-231 human breast cancer cells. The mechanism of the compounds on inhibiting heterotypic cell adhesion were further explored by determining the expression of epidermal growth factor receptor (EGFR), Intercellular adhesion molecule 1 (ICAM-1), αv-integrin, β1-integrin and β5-integrin by western blotting assay. In five tested alkaloids, only protopine exhibited anti-adhesive and anti-invasion effects in MDA-MB-231 cells, which contributed to the anti-metastasis effect of Corydalis yanhusuo. The results showed that after treatment with protopine for 90 min, the expression of EGFR, ICAM-1, αv-integrin, β1-integrin and β5-integrin were remarkably reduced. The present results suggest that protopine seems to inhibit the heterotypic cell adhesion between MDA-MB-231 cells, and human umbilical vein endothelial cells by changing the expression of adhesive factors.

  16. Inflammatory mediator mRNA expression by adenovirus E1A-transfected bronchial epithelial cells.

    PubMed

    Higashimoto, Yuji; Elliott, W Mark; Behzad, Ali R; Sedgwick, Edward G; Takei, Tatsuo; Hogg, James C; Hayashi, Shizu

    2002-07-15

    Lung tissue from patients with emphysema and airway obstruction carries excess adenoviral E1A DNA that is expressed as protein in airway surface epithelium and is associated with an increased inflammatory response. To examine mechanisms by which latent adenoviral infection might amplify the inflammatory process, we transfected primary human bronchial epithelial (HBE) cells from three separate patients undergoing lung resection so that they stably expressed adenovirus E1A. Lipopolysaccharide stimulation of the E1A-transfected HBE cells increased intercellular adhesion molecule-1 and interleukin-8 mRNA and protein expression compared with control cells from the same patient. It also induced greater intercellular adhesion molecule-1 promoter activity and greater nuclear factor-kappa B binding activity of nuclear extracts in E1A transfectants than controls. E1A-positive transfectants constitutively expressed transforming growth factor-beta 1 mRNA and protein, whereas this expression was either very low or not detected in control cells. We conclude that adenoviral E1A transfection transforms primary HBE cells and upregulates their production of mediators that are clinically relevant to the pathogenesis of chronic obstructive pulmonary disease.

  17. Elevation of soluble intercellular adhesion molecule-1 levels, but not angiopoietin 2, in the plasma of human immunodeficiency virus-infected African women with clinical Kaposi sarcoma.

    PubMed

    Graham, Susan M; Rajwans, Nimerta; Richardson, Barbra A; Jaoko, Walter; McClelland, R Scott; Overbaugh, Julie; Liles, W Conrad

    2014-10-01

    Circulating levels of endothelial activation biomarkers are elevated in during infection with human immunodeficiency virus 1 (HIV-1) and may also be increased in Kaposi sarcoma (KS). We compared 23 HIV-1-seropositive women with clinically diagnosed KS with 46 randomly selected controls matched for visit year, CD4 count, and antiretroviral therapy status. Conditional logistic regression was used to identify differences between cases and controls. The odds of clinical KS increased with increasing plasma viral load and with intercellular adhesion molecule 1 (ICAM-1) levels above or equal to the median. There was a borderline association between increasing plasma angiopoietin 2 levels and KS. In multivariable modeling including plasma viral load, angiopoietin 2, and ICAM-1, plasma ICAM-1 levels above or equal to the median remained associated with clinical KS (odds ratio = 14.2, 95% confidence interval = 2.3-87.7). Circulating ICAM-1 levels should be evaluated as a potential biomarker for disease progression and treatment response among HIV-infected KS patients. © The American Society of Tropical Medicine and Hygiene.

  18. Plasma concentration of soluble intercellular adhesion molecule-1 (sICAM-1) is elevated in type 2 diabetic patients, and sICAM-1 synthesis is associated with leptin-induced activation of the mitogen-activated protein kinase (MAPK) pathway.

    PubMed

    Cha, Jin Joo; Hyun, Young Youl; Jee, Yi Hwa; Lee, Mi Jin; Han, Kum Hyun; Kang, Young Sun; Han, Sang Youb; Cha, Dae Ryong

    2013-08-01

    The intercellular adhesion molecule-1 (ICAM-1) and leptin are important inflammatory biomarkers. We investigated whether plasma-soluble ICAM-1 levels were related to the diabetic nephropathy and systemic inflammation. One hundred forty-seven type 2 diabetic patients and 46 healthy control subjects were studied. Plasma sICAM-1 concentrations were significantly higher in the diabetic groups than controls and increased significantly as diabetic nephropathy advanced. Plasma sICAM-1 levels were positively correlated with body mass index, fasting and postprandial blood glucose, urinary albumin excretion, and negatively correlated with creatinine clearance. Multiple regression analysis showed that plasma leptin levels were associated with a significant increase in plasma sICAM-1 levels. In cultured HUVECs, leptin increased ICAM-1 production in a dose-dependent manner, and this stimulating effect of leptin on ICAM-1 expression was reversed by MEK inhibitor, PD98059. Overall, these findings suggest that activation of leptin synthesis in a diabetic environment promotes ICAM-1 activation via mitogen-activated protein kinase pathway in type 2 diabetic patients.

  19. Tetrandrine suppresses lung cancer growth and induces apoptosis, potentially via the VEGF/HIF-1α/ICAM-1 signaling pathway

    PubMed Central

    Chen, Zhuo; Zhao, Liang; Zhao, Feng; Yang, Guanghai; Wang, Jian Jun

    2018-01-01

    The present study investigated the effect of tetrandrine on lung cancer cell growth and apoptosis, and its possible underlying molecular mechanism. A549 human lung cancer cells were incubated with between 2.5 and 10 µM tetrandrine for 12, 24 and 48 h, following which the effect of tetrandrine on cell viability and apoptosis were assessed using an MTT assay and flow cytometry. ELISA and western blotting were used to analyze VEGF activity, and the expression of poly (ADP-ribose) polymerase (PARP), phosphorylated protein kinase B (Akt), Bcl-2-associated X protein (Bax), hypoxia inducible factor (HIF)-1α and inter-cellular adhesion molecule-1 (ICAM-1). Tetrandrine effectively suppressed the growth of and induced apoptosis in A549 lung cancer cells. The expression of PARP, Bax, intercellular adhesion molecule-1 (ICAM-1) and vascular endothelial growth factor (VEGF) was significantly upregulated, and the phosphorylation of Akt and expression of HIF-1α was significantly suppressed in A549 lung cancer cells. Therefore, tetrandrine may suppress cell viability and induce apoptosis via the VEGF/HIF-1α/ICAM-1 signaling pathway. PMID:29849794

  20. Comparative immunoexpression of ICAM-1, TGF-β1 and ki-67 in periapical and residual cysts

    PubMed Central

    Armada, Luciana; dos Santos, Teresa-Cristina; Pires, Fabio-Ramoa

    2017-01-01

    Background This study compared the immunohistochemical expression of ki-67, transforming growth factor beta 1 (TGF-β1) and intercellular adhesion molecule-1 (ICAM-1) in inflammatory periapical cysts and residual cysts. Material and Methods The study sample was composed by 25 periapical cysts and 25 residual cysts and immunohistochemical reactions were carried out using antibodies directed against ICAM-1, TGF-β1 and ki-67. Clinical, radiological, gross, histological and immunohistochemical data were tabulated for descriptive and comparative analysis using the SPSS software and differences were considered statistically significant when p<0.05%. Results There were no differences between the expression of ICAM-1 (p=0.239) and TGF-β1 (p=0.258) when comparing both groups. Ki-67 labeling index was higher in residual cysts compared to periapical cysts (p=0.017). Conclusions Results from the present study suggest that some specific inflammatory stimuli on residual cysts would modulate their mechanisms of etiopathogenesis, growing and repair. Key words:Periapical cyst, radicular cyst, residual cyst, transforming growth factor beta 1 (TGF-β1), intercellular adhesion molecule 1 (ICAM-1), ki-67. PMID:27918735

  1. Outer membrane protein A of Escherichia coli K1 selectively enhances the expression of intercellular adhesion molecule-1 in brain microvascular endothelial cells.

    PubMed

    Selvaraj, Suresh K; Periandythevar, Parameswaran; Prasadarao, Nemani V

    2007-04-01

    Escherichia coli K1 meningitis is a serious central nervous system disease with unchanged mortality and morbidity rates for last few decades. Intercellular adhesion molecule 1 (ICAM-1) is a cell adhesion molecule involved in leukocyte trafficking toward inflammatory stimuli at the vascular endothelium; however, the effect of E. coli invasion of endothelial cells on the expression of ICAM-1 is not known. We demonstrate here that E. coli K1 invasion of human brain microvascular endothelial cells (HBMEC) selectively up-regulates the expression of ICAM-1, which occurs only in HBMEC invaded by the bacteria. The interaction of outer membrane protein A (OmpA) of E. coli with its receptor, Ecgp, on HBMEC was critical for the up-regulation of ICAM-1 and was depend on PKC-alpha and PI3-kinase signaling. Of note, the E. coli-induced up-regulation of ICAM-1 was not due to the cytokines secreted by HBMEC upon bacterial infection. Activation of NF-kappaB was required for E. coli mediated expression of ICAM-1, which was significantly inhibited by over-expressing the dominant negative forms of PKC-alpha and p85 subunit of PI3-kinase. The increased expression of ICAM-1 also enhanced the binding of THP-1 cells to HBMEC. Taken together, these data suggest that localized increase in ICAM-1 expression in HBMEC invaded by E. coli requires a novel interaction between OmpA and its receptor, Ecgp.

  2. The interplay of plasma treatment and gold coating and ultra-high molecular weight polyethylene: On the cytocompatibility.

    PubMed

    Novotná, Zdenka; Rimpelová, Silvie; Juřík, Petr; Veselý, Martin; Kolská, Zdenka; Hubáček, Tomáš; Ruml, Tomáš; Švorčík, Václav

    2017-02-01

    We have investigated the application of Ar plasma for creation of nanostructured ultra high molecular weight polyethylene (PE) surface in order to enhance adhesion of mouse embryonic fibroblasts (L929). The aim of this study was to investigate the effect of the interface between plasma-treated and gold-coated PE on adhesion and spreading of cells. The surface properties of pristine samples and its modified counterparts were studied by different experimental techniques (gravimetry, goniometry and X-ray photoelectron spectroscopy (XPS), electrokinetic analysis), which were used for characterization of treated and sputtered layers, polarity and surface chemical structure, respectively. Further, atomic force microscopy (AFM) was employed to study the surface morphology and roughness. Biological responses of cells seeded on PE samples were evaluated in terms of cell adhesion, spreading, morphology and proliferation. Detailed cell morphology and intercellular connections were followed by scanning electron microscopy (SEM). As it was expected the thickness of a deposited gold film was an increasing function of the sputtering time. Despite the fact that plasma treatment proceeded in inert plasma, oxidized degradation products were formed on the PE surface which would contribute to increased hydrophilicity (wettability) of the plasma treated polymer. The XPS method showed a decrease in carbon concentration with increasing plasma treatment. Cell adhesion measured on the interface between plasma treated and gold coated PE was inversely proportional to the thickness of a gold layer on a sample. Copyright © 2016. Published by Elsevier B.V.

  3. Inhibition of tumor necrosis factor-{alpha}-induced expression of adhesion molecules in human endothelial cells by the saponins derived from roots of Platycodon grandiflorum

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Ji Young; Kim, Dong Hee; Kim, Hyung Gyun

    2006-01-15

    Adhesion molecules play an important role in the development of atherogenesis and are produced by endothelial cells after being stimulated with various inflammatory cytokines. This study examined the effect of saponins that were isolated from the roots of Platycodon grandiflorum A. DC (Campanulaceae), Changkil saponins (CKS), on the cytokine-induced monocyte/human endothelial cell interaction, which is a crucial early event in atherogenesis. CKS significantly inhibited the TNF{alpha}-induced increase in monocyte adhesion to endothelial cells as well as decreased the protein and mRNA expression levels of vascular adhesion molecule-1 and intercellular cell adhesion molecule-1 on endothelial cells. Furthermore, CKS significantly inhibited themore » TNF{alpha}-induced production of intracellular reactive oxygen species (ROS) and activation of NF-{kappa}B by preventing I{kappa}B degradation and inhibiting I{kappa}B kinase activity. Overall, CKS has anti-atherosclerotic and anti-inflammatory activity, which is least in part the result of it reducing the cytokine-induced endothelial adhesion to monocytes by inhibiting intracellular ROS production, NF-{kappa}B activation, and cell adhesion molecule expression in endothelial cells.« less

  4. Circulating soluble adhesion molecules in patients with giant cell arteritis. Correlation between soluble intercellular adhesion molecule-1 (sICAM-1) concentrations and disease activity

    PubMed Central

    Coll-Vinent, B.; Vilardell, C.; Font, C.; Oristrell, J.; Hernandez-Rodrigu..., J.; Yague, J.; Urbano-Marquez, A.; Grau, J.; Cid, M.

    1999-01-01

    OBJECTIVE—To evaluate whether changes in concentrations of circulating adhesion molecules are related to disease activity in patients with giant cell arteritis (GCA).
METHODS—A sandwich ELISA was used to measure soluble intercellular adhesion molecule-1 (sICAM-1), sICAM-3, vascular cell adhesion molecule-1 (sVCAM-1), E-selectin (sE-selectin), and L-selectin (sL-selectin) in serum and plasma samples from patients with GCA. A cross sectional study was performed on 64 GCA patients at different activity stages and on 35 age and sex matched healthy donors. Thirteen of these patients were evaluated at the time of diagnosis and serially during follow up.
RESULTS—At the time of diagnosis, sICAM-1 concentrations were significantly higher in active GCA patients than in controls (mean (SD) 360.55 (129.78) ng/ml versus 243.25 (47.43) ng/ml, p<0.001). In contrast, sICAM-3, sVCAM-1, sE-selectin, and sL-selectin values did not differ from those obtained in normal donors. With corticosteroid administration, a decrease in sICAM-1 concentrations was observed, reaching normal values when clinical remission was achieved (263.18 (92.7) ng/ml globally, 293.59 (108.39) ng/ml in the group of patients in recent remission, and 236.83 (70.02) ng/ml in those in long term remission). In the 13 patients followed up longitudinally, sICAM-1 values also normalised with clinical remission (225.87 (64.25) ng/ml in patients in recent remission, and 256.29 (75.15) ng/ml in those in long term remission).
CONCLUSIONS—Circulating sICAM-1 concentrations clearly correlate with clinically apparent disease activity in GCA patients. Differences with results previously found in patients with other vasculitides may indicate that different pathogenic mechanisms contribute to vascular inflammation in different disorders.

 Keywords: adhesion molecules; giant cell arteritis; inflammation PMID:10364919

  5. Endothelial Barrier Protection by Local Anesthetics: Ropivacaine and Lidocaine Block Tumor Necrosis Factor-α–induced Endothelial Cell Src Activation

    PubMed Central

    Piegeler, Tobias; Votta-Velis, E. Gina; Bakhshi, Farnaz R.; Mao, Mao; Carnegie, Graeme; Bonini, Marcelo G.; Schwartz, David E.; Borgeat, Alain; Beck-Schimmer, Beatrice; Minshall, Richard D.

    2014-01-01

    Background Pulmonary endothelial barrier dysfunction mediated in part by Src-kinase activation plays a crucial role in acute inflammatory disease. Proinflammatory cytokines, such as tumor necrosis factor-α (TNFα), activate Src via phosphatidylinositide 3-kinase/Akt-dependent nitric oxide generation, a process initiated by recruitment of phosphatidylinositide 3-kinase regulatory subunit p85 to TNF-receptor-1. Because amide-linked local anesthetics have well-established anti-inflammatory effects, the authors hypothesized that ropivacaine and lidocaine attenuate inflammatory Src signaling by disrupting the phosphatidylinositide 3-kinase–Akt–nitric oxide pathway, thus blocking Src-dependent neutrophil adhesion and endothelial hyperpermeability. Methods Human lung microvascular endothelial cells, incubated with TNFα in the absence or presence of clinically relevant concentrations of ropivacaine and lidocaine, were analyzed by Western blot, probing for phosphorylated/activated Src, endothelial nitric oxide synthase, Akt, intercellular adhesion molecule-1, and caveolin-1. The effect of ropivacaine on TNFα-induced nitric oxide generation, co-immunoprecipitation of TNF-receptor-1 with p85, neutrophil adhesion, and endothelial barrier disruption were assessed. Results Ropivacaine and lidocaine attenuated TNFα-induced Src activation (half-maximal inhibitory concentration [IC50] = 8.611 × 10−10 M for ropivacaine; IC50 = 5.864 × 10−10 M for lidocaine) and endothelial nitric oxide synthase phosphorylation (IC50 = 7.572 × 10−10 M for ropivacaine; IC50 = 6.377 × 10−10 M for lidocaine). Akt activation (n = 7; P = 0.006) and stimulus-dependent binding of TNF-receptor-1 and p85 (n = 6; P = 0.043) were blocked by 1 nM of ropivacaine. TNFα-induced neutrophil adhesion and disruption of endothelial monolayers via Src-dependent intercellular adhesion molecule-1- and caveolin-1-phosphorylation, respectively, were also attenuated. Conclusions Ropivacaine and lidocaine effectively blocked inflammatory TNFα signaling in endothelial cells by attenuating p85 recruitment to TNF-receptor-1. The resultant decrease in Akt, endothelial nitric oxide synthase, and Src phosphorylation reduced neutrophil adhesion and endothelial hyperpermeability. This novel anti-inflammatory “side-effect” of ropivacaine and lidocaine may provide therapeutic benefit in acute inflammatory disease. PMID:24525631

  6. Endothelial barrier protection by local anesthetics: ropivacaine and lidocaine block tumor necrosis factor-α-induced endothelial cell Src activation.

    PubMed

    Piegeler, Tobias; Votta-Velis, E Gina; Bakhshi, Farnaz R; Mao, Mao; Carnegie, Graeme; Bonini, Marcelo G; Schwartz, David E; Borgeat, Alain; Beck-Schimmer, Beatrice; Minshall, Richard D

    2014-06-01

    Pulmonary endothelial barrier dysfunction mediated in part by Src-kinase activation plays a crucial role in acute inflammatory disease. Proinflammatory cytokines, such as tumor necrosis factor-α (TNFα), activate Src via phosphatidylinositide 3-kinase/Akt-dependent nitric oxide generation, a process initiated by recruitment of phosphatidylinositide 3-kinase regulatory subunit p85 to TNF-receptor-1. Because amide-linked local anesthetics have well-established anti-inflammatory effects, the authors hypothesized that ropivacaine and lidocaine attenuate inflammatory Src signaling by disrupting the phosphatidylinositide 3-kinase-Akt-nitric oxide pathway, thus blocking Src-dependent neutrophil adhesion and endothelial hyperpermeability. Human lung microvascular endothelial cells, incubated with TNFα in the absence or presence of clinically relevant concentrations of ropivacaine and lidocaine, were analyzed by Western blot, probing for phosphorylated/activated Src, endothelial nitric oxide synthase, Akt, intercellular adhesion molecule-1, and caveolin-1. The effect of ropivacaine on TNFα-induced nitric oxide generation, co-immunoprecipitation of TNF-receptor-1 with p85, neutrophil adhesion, and endothelial barrier disruption were assessed. Ropivacaine and lidocaine attenuated TNFα-induced Src activation (half-maximal inhibitory concentration [IC50] = 8.611 × 10 M for ropivacaine; IC50 = 5.864 × 10 M for lidocaine) and endothelial nitric oxide synthase phosphorylation (IC50 = 7.572 × 10 M for ropivacaine; IC50 = 6.377 × 10 M for lidocaine). Akt activation (n = 7; P = 0.006) and stimulus-dependent binding of TNF-receptor-1 and p85 (n = 6; P = 0.043) were blocked by 1 nM of ropivacaine. TNFα-induced neutrophil adhesion and disruption of endothelial monolayers via Src-dependent intercellular adhesion molecule-1- and caveolin-1-phosphorylation, respectively, were also attenuated. Ropivacaine and lidocaine effectively blocked inflammatory TNFα signaling in endothelial cells by attenuating p85 recruitment to TNF-receptor-1. The resultant decrease in Akt, endothelial nitric oxide synthase, and Src phosphorylation reduced neutrophil adhesion and endothelial hyperpermeability. This novel anti-inflammatory "side-effect" of ropivacaine and lidocaine may provide therapeutic benefit in acute inflammatory disease.

  7. Clinical significance of circulating vascular cell adhesion molecule-1 to white matter disintegrity in Alzheimer's dementia.

    PubMed

    Huang, Chi-Wei; Tsai, Meng-Han; Chen, Nai-Ching; Chen, Wei-Hsi; Lu, Yan-Ting; Lui, Chun-Chung; Chang, Ya-Ting; Chang, Wen-Neng; Chang, Alice Y W; Chang, Chiung-Chih

    2015-11-25

    Endothelial dysfunction leads to worse cognitive performance in Alzheimer's dementia (AD). While both cerebrovascular risk factors and endothelial dysfunction lead to activation of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1) and E-selectin, it is not known whether these biomarkers extend the diagnostic repertoire in reflecting intracerebral structural damage or cognitive performance. A total of 110 AD patients and 50 age-matched controls were enrolled. Plasma levels of VCAM-1, ICAM-1 and E-selectin were measured and correlated with the cognitive performance, white matter macro-structural changes, and major tract-specific fractional anisotropy quantification. The AD patients were further stratified by clinical dementia rating score (mild dementia, n=60; moderate-to-severe dementia, n=50). Compared with the controls, plasma levels of VCAM-1 (p< 0.001), ICAM-1 (p=0.028) and E-selectin (p=0.016) were significantly higher in the patients, but only VCAM-1 levels significantly reflected the severity of dementia (p< 0.001). In addition, only VCAM-1 levels showed an association with macro- and micro- white matter changes especially in the superior longitudinal fasciculus (p< 0.001), posterior thalamic radiation (p=0.002), stria terminalis (p=0.002) and corpus callosum (p=0.009), and were independent of, age and cortical volume. These tracts show significant association with MMSE, short term memory and visuospatial function. Meanwhile, while VCAM-1 level correlated significantly with short-term memory (p=0.026) and drawing (p=0.025) scores in the AD patients after adjusting for age and education, the significance disappeared after adjusting for global FA. Endothelial activation, especially VCAM-1, was of clinical significance in AD that reflects macro- and micro-structural changes and poor short term memory and visuospatial function.

  8. Programming self-organizing multicellular structures with synthetic cell-cell signaling.

    PubMed

    Toda, Satoshi; Blauch, Lucas R; Tang, Sindy K Y; Morsut, Leonardo; Lim, Wendell A

    2018-05-31

    A common theme in the self-organization of multicellular tissues is the use of cell-cell signaling networks to induce morphological changes. We used the modular synNotch juxtacrine signaling platform to engineer artificial genetic programs in which specific cell-cell contacts induced changes in cadherin cell adhesion. Despite their simplicity, these minimal intercellular programs were sufficient to yield assemblies with hallmarks of natural developmental systems: robust self-organization into multi-domain structures, well-choreographed sequential assembly, cell type divergence, symmetry breaking, and the capacity for regeneration upon injury. The ability of these networks to drive complex structure formation illustrates the power of interlinking cell signaling with cell sorting: signal-induced spatial reorganization alters the local signals received by each cell, resulting in iterative cycles of cell fate branching. These results provide insights into the evolution of multi-cellularity and demonstrate the potential to engineer customized self-organizing tissues or materials. Copyright © 2018, American Association for the Advancement of Science.

  9. The nanoscale organization of signaling domains at the plasma membrane.

    PubMed

    Griffié, Juliette; Burn, Garth; Owen, Dylan M

    2015-01-01

    In this chapter, we present an overview of the role of the nanoscale organization of signaling domains in regulating key cellular processes. In particular, we illustrate the importance of protein and lipid nanodomains as triggers and mediators of cell signaling. As particular examples, we summarize the state of the art of understanding the role of nanodomains in the mounting of an immune response, cellular adhesion, intercellular communication, and cell proliferation. Thus, this chapter underlines the essential role the nanoscale organization of key signaling proteins and lipid domains. We will also see how nanodomains play an important role in the lifecycle of many pathogens relevant to human disease and therefore illustrate how these structures may become future therapeutic targets. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. DEVELOPMENT OF A MODEL TO INVESTIGATE RED BLOOD CELL SURFACE CHARACTERISTICS AFTER CRYOPRESERVATION.

    PubMed

    Gordiyenko, O I; Anikieieva, M O; Rozanova, S L; Kovalenko, S Ye; Kovalenkol, I F; Gordiyenko, E O

    2015-01-01

    Maintaining cell surface properties after freezing and thawing, characterized in particular by the surface potential and associated with it cell ability to intercellular adhesion, could be used as a characteristic of successful cryopreservation. This study was conducted to research applying different erythrocytes freezing modes and analyses the regimes cryopreservation effect on the cell surface charge and adhesion to microorganisms. Human erythrocytes frozen by three modes. In order to determine adhesion index was used dried bacterial cells of S. thermophilus. The surface charge of erythrocytes was evaluated using Alcian blue cationic dye. The results showed the significant decrease in the lactobacillus adhesion to erythrocytes frozen glycerol and 1,2-propanediol. After erythrocytes were freezen with glycerol and 1,2-propanediol, the cationic dye binding to erythrocytes significantly reduced. AB binding to erythrocytes frozen with PEG-1500 does not differ from control data. Erythrocytes frozen with PEG-1500 mantained surface properties after thawing better, compared to erythrocytes cryopreserved by other methods.

  11. Expression of adhesion molecules, chemokines and matrix metallo- proteinases (MMPs) in viable and degenerating stage of Taenia solium metacestode in swine neurocysticercosis.

    PubMed

    Singh, Satyendra K; Singh, Aloukick K; Prasad, Kashi N; Singh, Amrita; Singh, Avinash; Rai, Ravi P; Tripathi, Mukesh; Gupta, Rakesh K; Husain, Nuzhat

    2015-11-30

    Neurocysticercosis (NCC) is a parasitic infection of central nervous system (CNS). Expression of adhesion molecules, chemokines and matrix metalloproteinases (MMPs) were investigated on brain tissues surrounding viable (n=15) and degenerating cysticerci (n=15) of Taenia solium in swine by real-time RT-PCR and ELISA. Gelatin gel zymography was performed for MMPs activity. ICAM-1 (intercellular adhesion molecule-1), E-selectin, MIP-1α (macrophage inflammatory protein-1α), Eotaxin-1 and RANTES (regulated on activation, normal T cell expressed and secreted) were associated with degenerating cysticerci (cysts). However, VCAM-1 (vascular cell adhesion molecule-1), MCP-1 (monocyte chemotactic protein-1), MMP-2 and MMP-9 were associated with both viable and degenerating cysts. In conclusion, viable and degenerating cysticerci have different immune molecule profiles and role of these molecules in disease pathogenesis needs to be investigated. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Anisotropic forces from spatially constrained focal adhesions mediate contact guidance directed cell migration

    PubMed Central

    Ray, Arja; Lee, Oscar; Win, Zaw; Edwards, Rachel M.; Alford, Patrick W.; Kim, Deok-Ho; Provenzano, Paolo P.

    2017-01-01

    Directed migration by contact guidance is a poorly understood yet vital phenomenon, particularly for carcinoma cell invasion on aligned collagen fibres. We demonstrate that for single cells, aligned architectures providing contact guidance cues induce constrained focal adhesion maturation and associated F-actin alignment, consequently orchestrating anisotropic traction stresses that drive cell orientation and directional migration. Consistent with this understanding, relaxing spatial constraints to adhesion maturation either through reduction in substrate alignment density or reduction in adhesion size diminishes the contact guidance response. While such interactions allow single mesenchymal-like cells to spontaneously ‘sense' and follow topographic alignment, intercellular interactions within epithelial clusters temper anisotropic cell–substratum forces, resulting in substantially lower directional response. Overall, these results point to the control of contact guidance by a balance of cell–substratum and cell–cell interactions, modulated by cell phenotype-specific cytoskeletal arrangements. Thus, our findings elucidate how phenotypically diverse cells perceive ECM alignment at the molecular level. PMID:28401884

  13. γ-Oryzanol reduces adhesion molecule expression in vascular endothelial cells via suppression of nuclear factor-κB activation.

    PubMed

    Sakai, Satoshi; Murata, Takahisa; Tsubosaka, Yoshiki; Ushio, Hideki; Hori, Masatoshi; Ozaki, Hiroshi

    2012-04-04

    γ-Oryzanol (γ-ORZ) is a mixture of phytosteryl ferulates purified from rice bran oil. In this study, we examined whether γ-ORZ represents a suppressive effect on the lipopolysaccharide (LPS)-induced adhesion molecule expression on vascular endothelium. Treatment with LPS elevated the mRNA expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and E-selectin in bovine aortic endothelial cells (BAECs). Pretreatment with γ-ORZ dose-dependently decreased the LPS-mediated expression of these genes. Western blotting also revealed that pretreatment with γ-ORZ dose-dependently inhibited LPS-induced VCAM-1 expression in human umbilical vein endothelial cells. Consistently, pretreatment with γ-ORZ dose-dependently reduced LPS-induced U937 monocyte adhesion to BAECs. In immunofluorescence, LPS caused nuclear factor-κB (NF-κB) nuclear translocation in 40% of BAECs, which indicates NF-κB activation. Pretreatment with γ-ORZ, as well as its components (cycloartenyl ferulate, ferulic acid, or cycloartenol), dose-dependently inhibited LPS-mediated NF-κB activation. Collectively, our results suggested that γ-ORZ reduced LPS-mediated adhesion molecule expression through NF-κB inhibition in vascular endothelium.

  14. Withaferin A inhibits tumor necrosis factor-alpha-induced expression of cell adhesion molecules by inactivation of Akt and NF-kappaB in human pulmonary epithelial cells.

    PubMed

    Oh, Jung Hwa; Kwon, Taeg Kyu

    2009-05-01

    We here investigated the functional effect of withaferin A on airway inflammation and its action mechanism. Withaferin A inhibited the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in human lung epithelial A549 cells stimulated with tumor necrosis factor-alpha (TNF-alpha), resulting in the suppression of leukocyte adhesion to lung epithelial A549 cells. In addition, withaferin A inhibited TNF-alpha-induced expression of adhesion molecules (ICAM-1 and VCAM-1) protein and mRNA in a dose-dependent manner. Withaferin A prevented DNA binding activity of nuclear factor-kappaB (NF-kappaB) and nuclear translocation of NF-kappaB. It also inhibited phosphorylation of Akt and extracellular signal-regulated kinase (ERK), which are upstream in the regulation of adhesion molecules by TNF-alpha. Furthermore, withaferin A inhibited U937 monocyte adhesion to A549 cells stimulated by TNF-alpha, suggesting that it may inhibit the binding of these cells by regulating the expression of critical adhesion molecules by TNF-alpha. Taken together, these results suggest that withaferin A inhibits cell adhesion through inhibition of ICAM-1 and VCAM-1 expression, at least in part, by blocking Akt and down-regulating NF-kappaB activity.

  15. A novel adhering junction in the apical ciliary apparatus of the rotifer Brachionus plicatilis (Rotifera, Monogononta).

    PubMed

    Dallai, R; Lupetti, P; Lane, N J

    1996-10-01

    Cultures of the rotifer Brachionus plicatilis were examined with regard to their interepithelial junctions after infiltration with the extracellular tracer lanthanum, freeze-fracturing or quick-freeze deep-etching. The lateral borders between ciliated cells have an unusual apical adhering junction. This apical part of their intercellular cleft looks desmosome-like, but it is characterized by unusual intramembranous E-face clusters of particles. Deep-etching reveals that these are packed together in short rows which lie parallel to one another in orderly arrays. The true membrane surface in these areas features filaments in the form of short ribbons; these are produced by projections, possibly part of the glycocalyx, emerging from the membranes, between which the electron-dense tracer lanthanum permeates. These projections appear to overlap with each other in the centre of the intercellular cleft; this would provide a particularly flexible adaptation to maintain cell-cell contact and coordination as a consequence. The filamentous ribbons may be held in position by the intramembranous particle arrays since both have a similar size and distribution. These contacts are quite different from desmosomes and appear to represent a distinct new category of adhesive cell-cell junction. Beneath these novel structures, conventional pleated septate junctions are found, exhibiting the undulating intercellular ribbons typical of this junctional type, as well as the usual parallel alignments of intramembranous rows of EF grooves and PF particles. Below these are found gap junctions as close-packed plaques of intramembranous particles on either the P-face or E-face. After freeze-fracturing, the complementary fracture face to the particles shows pits, usually on the P-face, arrayed with a very precise hexagonal pattern.

  16. Identification of infection- and defense-related genes via a dynamic host-pathogen interaction network using a Candida albicans-zebrafish infection model.

    PubMed

    Kuo, Zong-Yu; Chuang, Yung-Jen; Chao, Chun-Cheih; Liu, Fu-Chen; Lan, Chung-Yu; Chen, Bor-Sen

    2013-01-01

    Candida albicans infections and candidiasis are difficult to treat and create very serious therapeutic challenges. In this study, based on interactive time profile microarray data of C. albicans and zebrafish during infection, the infection-related protein-protein interaction (PPI) networks of the two species and the intercellular PPI network between host and pathogen were simultaneously constructed by a dynamic interaction model, modeled as an integrated network consisting of intercellular invasion and cellular defense processes during infection. The signal transduction pathways in regulating morphogenesis and hyphal growth of C. albicans were further investigated based on significant interactions found in the intercellular PPI network. Two cellular networks were also developed corresponding to the different infection stages (adhesion and invasion), and then compared with each other to identify proteins from which we can gain more insight into the pathogenic role of hyphal development in the C. albicans infection process. Important defense-related proteins in zebrafish were predicted using the same approach. The hyphal growth PPI network, zebrafish PPI network and host-pathogen intercellular PPI network were combined to form an integrated infectious PPI network that helps us understand the systematic mechanisms underlying the pathogenicity of C. albicans and the immune response of the host, and may help improve medical therapies and facilitate the development of new antifungal drugs. Copyright © 2013 S. Karger AG, Basel.

  17. Ultrasound-microbubble-mediated intercellular adhesion molecule-1 small interfering ribonucleic acid transfection attenuates neointimal formation after arterial injury in mice.

    PubMed

    Suzuki, Jun-ichi; Ogawa, Masahito; Takayama, Kiyoshi; Taniyama, Yoshiaki; Morishita, Ryuichi; Hirata, Yasunobu; Nagai, Ryozo; Isobe, Mitsuaki

    2010-03-02

    The purpose of this study was to investigate the efficiency of small interfering ribonucleic acid (siRNA) in murine arteries. We transfected it using a nonviral ultrasound-microbubble-mediated in vivo gene delivery system. siRNA is an effective methodology to suppress gene function. The siRNA can be synthesized easily; however, a major obstacle in the use of siRNA as therapeutics is the difficulty involved in effective in vivo delivery. To investigate the efficiency of nonviral ultrasound-microbubble-mediated in vivo siRNA delivery, we used a fluorescein-labeled siRNA, green fluorescent protein (GFP) siRNA, and intercellular adhesion molecule (ICAM)-1 siRNA in murine arteries. Murine femoral arteries were injured using flexible wires to establish arterial injury. The fluorescein-labeled siRNA and GFP siRNA showed that this nonviral approach could deliver siRNA into target arteries effectively without any tissue damage and systemic adverse effects. ICAM-1 siRNA transfection into murine injured arteries significantly suppressed the development of neointimal formation in comparison to those in the control group. Immunohistochemistry revealed that accumulation of T cells and adhesion molecule positive cells was observed in nontreated injured arteries, whereas siRNA suppressed accumulation. The nonviral ultrasound-microbubble delivery of siRNA ensures effective transfection into target arteries. ICAM-1 siRNA has the potential to suppress arterial neointimal formation. Transfection of siRNA can be beneficial for the clinical treatment of cardiovascular and other inflammatory diseases. Copyright 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  18. Plasma levels of soluble intercellular adhesion molecule-1 as a biomarker for disease severity of patients with community-acquired pneumonia.

    PubMed

    Chang, Pin-Yu; Tsao, Shih-Ming; Chang, Jer-Hwa; Chien, Ming-Hsien; Hung, Wen-Yueh; Huang, Yi-Wen; Yang, Shun-Fa

    2016-12-01

    Community-acquired pneumonia (CAP) is characterized as an acute inflammation of the lung associated with the activation of macrophages and neutrophils. Intercellular adhesion molecule-1 (ICAM-1) is an essential adhesion molecule involved in immune cell recruitment in lung inflammation. We investigated whether ICAM-1 is a useful biomarker for assessing the disease severity of hospitalized adult patients with CAP. Plasma soluble ICAM-1 (sICAM-1) levels were measured in 78 patients with CAP and 69 healthy controls by using a commercial enzyme-linked immunosorbent assay. The pneumonia severity index scores were used to determine CAP severity in patients upon initial hospitalization. The sICAM-1 and C-reactive protein (CRP) levels decreased significantly in patients with CAP after antibiotic treatment. The plasma concentration of sICAM-1 alone, but not CRP, was correlated with CAP severity according to the pneumonia severity index scores (r=0.431, p<0.001). The sICAM-1 levels in patients with CAP with high mortality risk were significantly higher than those in patients with CAP with medium or low mortality risk. Moreover, the sICAM-1 level showed a significant correlation with the length of hospital stay (r=0.488, p<0.001). Mechanistic investigations found that bacterial lipopolysaccharide induced upregulation of ICAM-1 expression through the c-Jun N-terminal kinase pathway in RAW264.7 macrophages. Plasma sICAM-1 levels may play a role in the diagnosis and clinical assessment of CAP severity. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Polystyrene-Divinylbenzene-Based Adsorbents Reduce Endothelial Activation and Monocyte Adhesion Under Septic Conditions in a Pore Size-Dependent Manner.

    PubMed

    Eichhorn, Tanja; Rauscher, Sabine; Hammer, Caroline; Gröger, Marion; Fischer, Michael B; Weber, Viktoria

    2016-10-01

    Endothelial activation with excessive recruitment and adhesion of immune cells plays a central role in the progression of sepsis. We established a microfluidic system to study the activation of human umbilical vein endothelial cells by conditioned medium containing plasma from lipopolysaccharide-stimulated whole blood or from septic blood and to investigate the effect of adsorption of inflammatory mediators on endothelial activation. Treatment of stimulated whole blood with polystyrene-divinylbenzene-based cytokine adsorbents (average pore sizes 15 or 30 nm) prior to passage over the endothelial layer resulted in significantly reduced endothelial cytokine and chemokine release, plasminogen activator inhibitor-1 secretion, adhesion molecule expression, and in diminished monocyte adhesion. Plasma samples from sepsis patients differed substantially in their potential to induce endothelial activation and monocyte adhesion despite their almost identical interleukin-6 and tumor necrosis factor-alpha levels. Pre-incubation of the plasma samples with a polystyrene-divinylbenzene-based adsorbent (30 nm average pore size) reduced endothelial intercellular adhesion molecule-1 expression to baseline levels, resulting in significantly diminished monocyte adhesion. Our data support the potential of porous polystyrene-divinylbenzene-based adsorbents to reduce endothelial activation under septic conditions by depletion of a broad range of inflammatory mediators.

  20. Cytoadherence and sequestration in Plasmodium falciparum: defining the ties that bind.

    PubMed

    Sherman, Irwin W; Eda, Shigetoshi; Winograd, Enrique

    2003-08-01

    Infected erythrocytes containing the more mature stages of the human malaria Plasmodium falciparum may adhere to endothelial cells and uninfected red cells. These phenomena, called sequestration and rosetting, respectively, are involved in both host pathogenesis and parasite survival. This review provides a critical summary of recent advances in the characterization of the molecules of the infected red blood cell involved in adhesion, i.e. parasite-encoded molecules (PfEMP1, MESA, rifins, stevor, clag 9, histidine-rich protein), a modified host membrane protein (band 3) and exofacial exposure of phosphatidylserine, as well as receptors on the endothelium, i.e. thrombospondin, CD36, ICAM-1 (intercellular adhesion molecule), and chondroitin sulfate.

  1. Redox sensor CtBP mediates hypoxia-induced tumor cell migration

    PubMed Central

    Zhang, Qinghong; Wang, Su-Yan; Nottke, Amanda C.; Rocheleau, Jonathan V.; Piston, David W.; Goodman, Richard H.

    2006-01-01

    The rapid growth and poor vascularization of solid tumors expose cancer cells to hypoxia, which promotes the metastatic phenotype by reducing intercellular adhesion and increasing cell motility and invasiveness. In this study, we found that hypoxia increased free NADH levels in cancer cells, promoting CtBP recruitment to the E-cadherin promoter. This effect was blocked by pyruvate, which prevents the NADH increase. Furthermore, hypoxia repressed E-cadherin gene expression and increased tumor cell migration, effects that were blocked by CtBP knockdown. We propose that CtBP senses levels of free NADH to control expression of cell adhesion genes, thereby promoting tumor cell migration under hypoxic stress. PMID:16740659

  2. Delivery of acid sphingomyelinase in normal and niemann-pick disease mice using intercellular adhesion molecule-1-targeted polymer nanocarriers.

    PubMed

    Garnacho, Carmen; Dhami, Rajwinder; Simone, Eric; Dziubla, Thomas; Leferovich, John; Schuchman, Edward H; Muzykantov, Vladimir; Muro, Silvia

    2008-05-01

    Type B Niemann-Pick disease (NPD) is a multiorgan system disorder caused by a genetic deficiency of acid sphingomyelinase (ASM), for which lung is an important and challenging therapeutic target. In this study, we designed and evaluated new delivery vehicles for enzyme replacement therapy of type B NPD, consisting of polystyrene and poly(lactic-coglycolic) acid polymer nanocarriers targeted to intercellular adhesion molecule (ICAM)-1, an endothelial surface protein up-regulated in many pathologies, including type B NPD. Real-time vascular imaging using intravital microscopy and postmortem imaging of mouse organs showed rapid, uniform, and efficient binding of fluorescently labeled ICAM-1-targeted ASM nanocarriers (anti-ICAM/ASM nanocarriers) to endothelium after i.v. injection in mice. Fluorescence microscopy of lung alveoli actin, tissue histology, and 125I-albumin blood-to-lung transport showed that anti-ICAM nanocarriers cause neither detectable lung injury, nor abnormal vascular permeability in animals. Radioisotope tracing showed rapid disappearance from the circulation and enhanced accumulation of anti-ICAM/125I-ASM nanocarriers over the nontargeted naked enzyme in kidney, heart, liver, spleen, and primarily lung, both in wild-type and ASM knockout mice. These data demonstrate that ICAM-1-targeted nanocarriers may enhance enzyme replacement therapy for type B NPD and perhaps other lysosomal storage disorders.

  3. Combined effects of physiologically relevant disturbed wall shear stress and glycated albumin on endothelial cell functions associated with inflammation, thrombosis and cytoskeletal dynamics.

    PubMed

    Maria, Zahra; Yin, Wei; Rubenstein, David Alan

    2014-07-01

    Diabetes mellitus is a major risk factor in the development of cardiovascular diseases (CVDs). The presence of advanced glycation end-products (AGEs) promotes CVDs by upregulating endothelial cell (EC) inflammatory and thrombotic responses, in a similar manner as disturbed shear stress. However, the combined effect of disturbed shear stress and AGEs on EC function has yet to be determined. Our goal was to evaluate these effects on EC responses. ECs were incubated with AGEs for 5 days. ECs were then subjected to physiological or pathological shear stress. Cell metabolic activity, surface expression of intercellular adhesion molecule-1, thrombomodulin, connexin-43 and caveolin-1, and cytoskeleton organization were quantified. The results show that irreversibly glycated albumin and pathological shear stress increased EC metabolic activity, and upregulated and downregulated the EC surface expression of intercellular adhesion molecule-1 and thrombomodulin, respectively. Expression of connexin-43, caveolin-1 and cytoskeletal organization was independent of shear stress; however, the presence of irreversibly glycated AGEs markedly increased connexin-43, and decreased caveolin-1 expression and actin cytoskeletal connectivity. Our data suggest that irreversibly glycated albumin and disturbed shear stress could promote CVD pathogenesis by enhancing EC inflammatory and thrombotic responses, and through the deterioration of the cytoskeletal organization.

  4. Ca2+-dependent localization of integrin-linked kinase to cell junctions in differentiating keratinocytes.

    PubMed

    Vespa, Alisa; Darmon, Alison J; Turner, Christopher E; D'Souza, Sudhir J A; Dagnino, Lina

    2003-03-28

    Integrin complexes are necessary for proper proliferation and differentiation of epidermal keratinocytes. Differentiation of these cells is accompanied by down-regulation of integrins and focal adhesions as well as formation of intercellular adherens junctions through E-cadherin homodimerization. A central component of integrin adhesion complexes is integrin-linked kinase (ILK), which can induce loss of E-cadherin expression and epithelial-mesenchymal transformation when ectopically expressed in intestinal and mammary epithelia. In cultured primary mouse keratinocytes, we find that ILK protein levels are independent of integrin expression and signaling, since they remain constant during Ca(2+)-induced differentiation. In contrast, keratinocyte differentiation is accompanied by marked reduction in kinase activity in ILK immunoprecipitates and altered ILK subcellular distribution. Specifically, ILK distributes in close apposition to actin fibers along intercellular junctions in differentiated but not in undifferentiated keratinocytes. ILK localization to cell-cell borders occurs independently of integrin signaling and requires Ca(2+) as well as an intact actin cytoskeleton. Further, and in contrast to what is observed in other epithelial cells, ILK overexpression in differentiated keratinocytes does not promote E-cadherin down-regulation and epithelial-mesenchymal transition. Thus, novel tissue-specific mechanisms control the formation of ILK complexes associated with cell-cell junctions in differentiating murine epidermal keratinocytes.

  5. Activation of human gingival epithelial cells by cell-surface components of black-pigmented bacteria: augmentation of production of interleukin-8, granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor and expression of intercellular adhesion molecule 1.

    PubMed

    Sugiyama, A; Uehara, A; Iki, K; Matsushita, K; Nakamura, R; Ogawa, T; Sugawara, S; Takada, H

    2002-01-01

    Black-pigmented anaerobic bacteria, such as Porphyromonas gingivalis and Prevotella intermedia, are amongst the predominant bacteria in periodontal pockets and have been implicated in periodontal diseases. To elucidate the roles of gingival keratinocytes, which are the first cells encountered by oral bacteria in periodontal diseases, human gingival keratinocytes in primary culture were stimulated with cell-surface components of P gingivalis and Pr. intermedia. A glycoprotein fraction from Pr. intermedia (PGP) clearly augmented the release of interleukin-8, granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor, as determined by enzyme-linked immunosorbent assay. This PGP also induced expression of intercellular adhesion molecule-1 (ICAM-1), as determined by flow cytometry. The augmentation of mRNA expression for these molecules was also confirmed by reverse transcription PCR. In contrast, lipopolysaccharide (LPS) from Pr. intermedia and Escherichia coli was completely inactive in these assays. LPS fraction and purified fimbriae from P gingivalis exhibited weak activities. Cytokine production and ICAM-1 expression by gingival keratinocytes might cause accumulation and activation of neutrophils in the epithelium and, therefore, may be involved in the initiation and development of inflammation in periodontal tissues.

  6. Effects of anti-tumor necrosis factor-alpha and anti-intercellular adhesion molecule-1 antibodies on ischemia/reperfusion lung injury.

    PubMed

    Chiang, Chi-Huei

    2006-10-31

    Inhibition of neutrophil activation and adherence to endothelium by antibodies to tumor necrosis factor-alpha (TNF-alpha) and intercellular adhesion molecules (ICAM-1), respectively, might attenuate ischemia-reperfusion injury (I/R). I/R was conducted in an isolated rat lung model. Anti-TNF-alpha antibody and/or anti-ICAM-1 antibody were added before ischemia or after reperfusion. Hemodynamic changes, lung weight gain (LWG), capillary filtration coefficients (Kfc), and pathologic changes were assessed to evaluate the severity of I/R. The LWG, Kfc, pathological changes and lung injury score of treatment groups with anti-TNF-alpha antibody treatment, either pre-ischemia or during reperfusion, were less than those observed in control groups. Similar findings were found in group treated with anti-ICAM-1 antibody or combination therapy during reperfusion. In contrast, pre-I/R treatment with anti-ICAM-1 antibody induced severe lung edema and failure to complete the experimental procedure. No additional therapeutic effect was found in combination therapy. We conclude that TNF-alpha and ICAM-1 play important roles in I/R. Anti-TNF-alpha antibody has therapeutic and preventive effects on I/R. However, combined therapy with anti-TNF-alpha antibody and anti-ICAM-1 antibody may have no additive effect and need further investigation.

  7. PAI1 mediates fibroblast-mast cell interactions in skin fibrosis.

    PubMed

    Pincha, Neha; Hajam, Edries Yousaf; Badarinath, Krithika; Batta, Surya Prakash Rao; Masudi, Tafheem; Dey, Rakesh; Andreasen, Peter; Kawakami, Toshiaki; Samuel, Rekha; George, Renu; Danda, Debashish; Jacob, Paul Mazhuvanchary; Jamora, Colin

    2018-05-01

    Fibrosis is a prevalent pathological condition arising from the chronic activation of fibroblasts. This activation results from the extensive intercellular crosstalk mediated by both soluble factors and direct cell-cell connections. Prominent among these are the interactions of fibroblasts with immune cells, in which the fibroblast-mast cell connection, although acknowledged, is relatively unexplored. We have used a Tg mouse model of skin fibrosis, based on expression of the transcription factor Snail in the epidermis, to probe the mechanisms regulating mast cell activity and the contribution of these cells to this pathology. We have discovered that Snail-expressing keratinocytes secrete plasminogen activator inhibitor type 1 (PAI1), which functions as a chemotactic factor to increase mast cell infiltration into the skin. Moreover, we have determined that PAI1 upregulates intercellular adhesion molecule type 1 (ICAM1) expression on dermal fibroblasts, rendering them competent to bind to mast cells. This heterotypic cell-cell adhesion, also observed in the skin fibrotic disorder scleroderma, culminates in the reciprocal activation of both mast cells and fibroblasts, leading to the cascade of events that promote fibrogenesis. Thus, we have identified roles for PAI1 in the multifactorial program of fibrogenesis that expand its functional repertoire beyond its canonical role in plasmin-dependent processes.

  8. Molecular Magnetic Resonance Imaging of Endothelial Activation in the Central Nervous System

    PubMed Central

    Gauberti, Maxime; Fournier, Antoine P.; Docagne, Fabian; Vivien, Denis; Martinez de Lizarrondo, Sara

    2018-01-01

    Endothelial cells of the central nervous system over-express surface proteins during neurological disorders, either as a cause, or a consequence, of the disease. Since the cerebral vasculature is easily accessible by large contrast-carrying particles, it constitutes a target of choice for molecular magnetic resonance imaging (MRI). In this review, we highlight the most recent advances in molecular MRI of brain endothelial activation and focus on the development of micro-sized particles of iron oxide (MPIO) targeting adhesion molecules including intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), P-Selectin and E-Selectin. We also discuss the perspectives and challenges for the clinical application of this technology in neurovascular disorders (ischemic stroke, intracranial hemorrhage, subarachnoid hemorrhage, diabetes mellitus), neuroinflammatory disorders (multiple sclerosis, brain infectious diseases, sepsis), neurodegenerative disorders (Alzheimer's disease, vascular dementia, aging) and brain cancers (primitive neoplasms, metastasis). PMID:29507614

  9. Glial response to polyglutamine-mediated stress

    PubMed Central

    Vig, Parminder J.S.; Shao, Qingmei; Lopez, Maripar E

    2009-01-01

    Neurodegenerative trinucleotide (CAG) repeat disorders are caused by the expansion of polyglutamine tracts within the disease proteins. Some of these proteins have an unknown function. How does expanded polyglutamine cause target neurons to degenerate, is not clear. Recent evidence suggests that intercellular miscommunication may contribute to polyglutamine pathogenesis in CAG repeat disorders. Polyglutamine induced degeneration of the target neuron can be mediated via glia-neuron interactions. Here we hypothesize during neurodegenerative process the failure of cell: cell interactions have more severe consequences than alterations in intracellular neuron biology. We further believe that bidirectional communication between neurons and glia are prerequisite for the normal development and function of either cell-type. Understanding intercellular signaling mechanisms such as glial trophic factors and their receptors, cell adhesion or other well-defined signaling molecules provide opportunities for developing potential therapies. PMID:20046986

  10. Monocyte chemoattractant protein 1, intercellular adhesion molecule 1, and vascular cell adhesion molecule 1 in exudative age-related macular degeneration.

    PubMed

    Jonas, Jost B; Tao, Yong; Neumaier, Michael; Findeisen, Peter

    2010-10-01

    To examine intraocular concentrations of monocyte chemoattractant protein 1 (MCP-1), soluble intercellular adhesion molecule 1 (sICAM-1), soluble vascular cell adhesion molecule 1 (sVCAM-1), and vascular endothelial growth factor (VEGF) in eyes with exudative age-related macular degeneration (AMD). The investigation included a study group of 28 patients (28 eyes) with exudative AMD and a control group of 25 patients (25 eyes) with cataract. The concentrations of MCP-1, sICAM-1, sVCAM-1, and VEGF in aqueous humor samples obtained during surgery were measured using a solid-phase chemiluminescence immunoassay. The study group as compared with the control group had higher aqueous concentrations of sICAM-1 (mean [SD], 844 [2073] vs 246 [206] pg/mL, respectively; P < .001), sVCAM-1 (mean [SD], 7978 [7120] vs 2999 [1426] pg/mL, respectively; P < .001), and MCP-1 (mean [SD], 587 [338] vs 435 [221] pg/mL, respectively; P = .07). The concentration of VEGF did not vary significantly between the groups (P = .76). The MCP-1 concentration was significantly associated with macular thickness (r = 0.40; P = .004). It decreased significantly with the type of subfoveal neovascular membrane (classic membrane type, occult membrane, retinal pigment epithelium detachment) (P = .009). The concentrations of sICAM-1, sVCAM-1, and VEGF were not significantly associated with membrane type and macular thickness (P ≥ .18). Concentrations of MCP-1, sICAM-1, and sVCAM-1 are significantly associated with exudative AMD, even in the presence of normal VEGF concentrations. Intraocular MCP-1 concentrations are correlated with the subfoveal neovascular membrane type and the amount of macular edema. One may infer that MCP-1, sICAM-1, and sVCAM-1 could potentially be additional target molecules in therapy for exudative AMD.

  11. Characterization of a Distinct Population of Circulating Human Non-Adherent Endothelial Forming Cells and Their Recruitment via Intercellular Adhesion Molecule-3

    PubMed Central

    Thompson, Emma J.; Barrett, Jeffrey M.; Tooley, Katie; Sen, Shaundeep; Sun, Wai Yan; Grose, Randall; Nicholson, Ian; Levina, Vitalina; Cooke, Ira; Talbo, Gert; Lopez, Angel F.; Bonder, Claudine S.

    2012-01-01

    Circulating vascular progenitor cells contribute to the pathological vasculogenesis of cancer whilst on the other hand offer much promise in therapeutic revascularization in post-occlusion intervention in cardiovascular disease. However, their characterization has been hampered by the many variables to produce them as well as their described phenotypic and functional heterogeneity. Herein we have isolated, enriched for and then characterized a human umbilical cord blood derived CD133+ population of non-adherent endothelial forming cells (naEFCs) which expressed the hematopoietic progenitor cell markers (CD133, CD34, CD117, CD90 and CD38) together with mature endothelial cell markers (VEGFR2, CD144 and CD31). These cells also expressed low levels of CD45 but did not express the lymphoid markers (CD3, CD4, CD8) or myeloid markers (CD11b and CD14) which distinguishes them from ‘early’ endothelial progenitor cells (EPCs). Functional studies demonstrated that these naEFCs (i) bound Ulex europaeus lectin, (ii) demonstrated acetylated-low density lipoprotein uptake, (iii) increased vascular cell adhesion molecule (VCAM-1) surface expression in response to tumor necrosis factor and (iv) in co-culture with mature endothelial cells increased the number of tubes, tubule branching and loops in a 3-dimensional in vitro matrix. More importantly, naEFCs placed in vivo generated new lumen containing vasculature lined by CD144 expressing human endothelial cells (ECs). Extensive genomic and proteomic analyses of the naEFCs showed that intercellular adhesion molecule (ICAM)-3 is expressed on their cell surface but not on mature endothelial cells. Furthermore, functional analysis demonstrated that ICAM-3 mediated the rolling and adhesive events of the naEFCs under shear stress. We suggest that the distinct population of naEFCs identified and characterized here represents a new valuable therapeutic target to control aberrant vasculogenesis. PMID:23144795

  12. Roles of inflammation and apoptosis in experimental brain death-induced right ventricular failure.

    PubMed

    Belhaj, Asmae; Dewachter, Laurence; Rorive, Sandrine; Remmelink, Myriam; Weynand, Birgit; Melot, Christian; Galanti, Laurence; Hupkens, Emeline; Sprockeels, Thomas; Dewachter, Céline; Creteur, Jacques; McEntee, Kathleen; Naeije, Robert; Rondelet, Benoît

    2016-12-01

    Right ventricular (RV) dysfunction remains the leading cause of early death after cardiac transplantation. Methylprednisolone is used to improve graft quality; however, evidence for that remains empirical. We sought to determine whether methylprednisolone, acting on inflammation and apoptosis, might prevent brain death-induced RV dysfunction. After randomization to placebo (n = 11) or to methylprednisolone (n = 8; 15 mg/kg), 19 pigs were assigned to a brain-death procedure. The animals underwent hemodynamic evaluation at 1 and 5 hours after Cushing reflex (i.e., hypertension and bradycardia). The animals euthanized, and myocardial tissue was sampled. This was repeated in a control group (n = 8). At 5 hours after the Cushing reflex, brain death resulted in increased pulmonary artery pressure (27 ± 2 vs 18 ± 1 mm Hg) and in a 30% decreased ratio of end-systolic to pulmonary arterial elastances (Ees/Ea). Cardiac output and right atrial pressure did not change. This was prevented by methylprednisolone. Brain death-induced RV dysfunction was associated with increased RV expression of heme oxygenase-1, interleukin (IL)-6, IL-10, IL-1β, tumor necrosis factor (TNF)-α, IL-1 receptor-like (ST)-2, signal transducer and activator of transcription-3, intercellular adhesion molecules-1 and -2, vascular cell adhesion molecule-1, and neutrophil infiltration, whereas IL-33 expression decreased. RV apoptosis was confirmed by terminal deoxynucleotide transferase-mediated deoxy uridine triphosphate nick-end labeling staining. Methylprednisolone pre-treatment prevented RV-arterial uncoupling and decreased RV expression of TNF-α, IL-1 receptor-like-2, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and neutrophil infiltration. RV Ees/Ea was inversely correlated to RV TNF-α and IL-6 expression. Brain death-induced RV dysfunction is associated with RV activation of inflammation and apoptosis and is partly limited by methylprednisolone. Copyright © 2016 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  13. Pathways and Progress in Improving Drug Delivery through the Intestinal Mucosa and Blood-Brain Barriers

    PubMed Central

    Laksitorini, Marlyn; Prasasty, Vivitri D.; Kiptoo, Paul K.; Siahaan, Teruna J.

    2015-01-01

    One of the major hurdles in developing therapeutic agents is the difficulty in delivering drugs through the intestinal mucosa and blood-brain barriers (BBB). The goal here is to describe the general structures of the biological barriers and the strategies to enhance drug delivery across these barriers. Prodrug methods used to improve drug penetration via the transcellular pathway have been successfully developed, and some prodrugs have been used to treat patients. The use of transporters to improve absorption of some drugs (e.g., antiviral agents) has also been successful in treating patients. Other methods, including (a) blocking the efflux pumps to improve transcellular delivery and (b) modulation of cell-cell adhesion in the intercellular junctions to improve paracellular delivery across biological barriers are still in the investigational stage. PMID:25418271

  14. Organoids with cancer stem cell-like properties secrete exosomes and HSP90 in a 3D nanoenvironment.

    PubMed

    Eguchi, Takanori; Sogawa, Chiharu; Okusha, Yuka; Uchibe, Kenta; Iinuma, Ryosuke; Ono, Kisho; Nakano, Keisuke; Murakami, Jun; Itoh, Manabu; Arai, Kazuya; Fujiwara, Toshifumi; Namba, Yuri; Murata, Yoshiki; Ohyama, Kazumi; Shimomura, Manami; Okamura, Hirohiko; Takigawa, Masaharu; Nakatsura, Tetsuya; Kozaki, Ken-Ichi; Okamoto, Kuniaki; Calderwood, Stuart K

    2018-01-01

    Ability to form cellular aggregations such as tumorspheres and spheroids have been used as a morphological marker of malignant cancer cells and in particular cancer stem cells (CSC). However, the common definition of the types of cellular aggregation formed by cancer cells has not been available. We examined morphologies of 67 cell lines cultured on three dimensional morphology enhancing NanoCulture Plates (NCP) and classified the types of cellular aggregates that form. Among the 67 cell lines, 49 cell lines formed spheres or spheroids, 8 cell lines formed grape-like aggregation (GLA), 8 cell lines formed other types of aggregation, and 3 cell lines formed monolayer sheets. Seven GLA-forming cell lines were derived from adenocarcinoma among the 8 lines. A neuroendocrine adenocarcinoma cell line PC-3 formed asymmetric GLA with ductal structures on the NCPs and rapidly growing asymmetric tumors that metastasized to lymph nodes in immunocompromised mice. In contrast, another adenocarcinoma cell line DU-145 formed spheroids in vitro and spheroid-like tumors in vivo that did not metastasize to lymph nodes until day 50 after transplantation. Culture in the 3D nanoenvironment and in a defined stem cell medium enabled the neuroendocrine adenocarcinoma cells to form slowly growing large organoids that expressed multiple stem cell markers, neuroendocrine markers, intercellular adhesion molecules, and oncogenes in vitro. In contrast, the more commonly used 2D serum-contained environment reduced intercellular adhesion and induced mesenchymal transition and promoted rapid growth of the cells. In addition, the 3D stemness nanoenvironment promoted secretion of HSP90 and EpCAM-exosomes, a marker of CSC phenotype, from the neuroendocrine organoids. These findings indicate that the NCP-based 3D environment enables cells to form stem cell tumoroids with multipotency and model more accurately the in vivo tumor status at the levels of morphology and gene expression.

  15. Organoids with cancer stem cell-like properties secrete exosomes and HSP90 in a 3D nanoenvironment

    PubMed Central

    Okusha, Yuka; Uchibe, Kenta; Iinuma, Ryosuke; Ono, Kisho; Nakano, Keisuke; Murakami, Jun; Itoh, Manabu; Arai, Kazuya; Fujiwara, Toshifumi; Namba, Yuri; Murata, Yoshiki; Ohyama, Kazumi; Shimomura, Manami; Okamura, Hirohiko; Takigawa, Masaharu; Nakatsura, Tetsuya; Kozaki, Ken-ichi; Okamoto, Kuniaki; Calderwood, Stuart K.

    2018-01-01

    Ability to form cellular aggregations such as tumorspheres and spheroids have been used as a morphological marker of malignant cancer cells and in particular cancer stem cells (CSC). However, the common definition of the types of cellular aggregation formed by cancer cells has not been available. We examined morphologies of 67 cell lines cultured on three dimensional morphology enhancing NanoCulture Plates (NCP) and classified the types of cellular aggregates that form. Among the 67 cell lines, 49 cell lines formed spheres or spheroids, 8 cell lines formed grape-like aggregation (GLA), 8 cell lines formed other types of aggregation, and 3 cell lines formed monolayer sheets. Seven GLA-forming cell lines were derived from adenocarcinoma among the 8 lines. A neuroendocrine adenocarcinoma cell line PC-3 formed asymmetric GLA with ductal structures on the NCPs and rapidly growing asymmetric tumors that metastasized to lymph nodes in immunocompromised mice. In contrast, another adenocarcinoma cell line DU-145 formed spheroids in vitro and spheroid-like tumors in vivo that did not metastasize to lymph nodes until day 50 after transplantation. Culture in the 3D nanoenvironment and in a defined stem cell medium enabled the neuroendocrine adenocarcinoma cells to form slowly growing large organoids that expressed multiple stem cell markers, neuroendocrine markers, intercellular adhesion molecules, and oncogenes in vitro. In contrast, the more commonly used 2D serum-contained environment reduced intercellular adhesion and induced mesenchymal transition and promoted rapid growth of the cells. In addition, the 3D stemness nanoenvironment promoted secretion of HSP90 and EpCAM-exosomes, a marker of CSC phenotype, from the neuroendocrine organoids. These findings indicate that the NCP-based 3D environment enables cells to form stem cell tumoroids with multipotency and model more accurately the in vivo tumor status at the levels of morphology and gene expression. PMID:29415026

  16. Serum Amyloid A Promotes E-Selectin Expression via Toll-Like Receptor 2 in Human Aortic Endothelial Cells.

    PubMed

    Nishida, Eisaku; Aino, Makoto; Kobayashi, Shu-Ichiro; Okada, Kosuke; Ohno, Tasuku; Kikuchi, Takeshi; Hayashi, Jun-Ichiro; Yamamoto, Genta; Hasegawa, Yoshiaki; Mitani, Akio

    2016-01-01

    Periodontitis is a chronic inflammatory disease that affects the periodontium. Recent studies suggest an association between periodontal and cardiovascular diseases. However, the detailed molecular mechanism is unknown. A previous study has demonstrated that experimental periodontitis induces serum amyloid A (SAA) in the liver and peripheral blood of ApoE-deficient mice as an atherosclerosis model. SAA is an acute-phase protein that affects systemic inflammation. The aim of this study is to investigate the atherosclerosis-onset mechanism using human aortic endothelial cells (HAECs) stimulated by SAA in vitro . Atherosclerosis PCR array and qPCR analyses showed upregulation of adhesion molecules such as intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin in HAECs upon SAA stimulation. In addition, the results demonstrated that Toll-like receptor, TLR2, could serve as an important receptor of SAA in HAECs. Furthermore, small interfering RNA (siRNA) against TLR2 inhibited the upregulation of adhesion molecules in HAECs stimulated by SAA. Our results suggest that SAA stimulates the expression of adhesion molecules via TLR2. SAA could be an important molecule for atherosclerosis induced by periodontal disease.

  17. Serum Amyloid A Promotes E-Selectin Expression via Toll-Like Receptor 2 in Human Aortic Endothelial Cells

    PubMed Central

    2016-01-01

    Periodontitis is a chronic inflammatory disease that affects the periodontium. Recent studies suggest an association between periodontal and cardiovascular diseases. However, the detailed molecular mechanism is unknown. A previous study has demonstrated that experimental periodontitis induces serum amyloid A (SAA) in the liver and peripheral blood of ApoE-deficient mice as an atherosclerosis model. SAA is an acute-phase protein that affects systemic inflammation. The aim of this study is to investigate the atherosclerosis-onset mechanism using human aortic endothelial cells (HAECs) stimulated by SAA in vitro. Atherosclerosis PCR array and qPCR analyses showed upregulation of adhesion molecules such as intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin in HAECs upon SAA stimulation. In addition, the results demonstrated that Toll-like receptor, TLR2, could serve as an important receptor of SAA in HAECs. Furthermore, small interfering RNA (siRNA) against TLR2 inhibited the upregulation of adhesion molecules in HAECs stimulated by SAA. Our results suggest that SAA stimulates the expression of adhesion molecules via TLR2. SAA could be an important molecule for atherosclerosis induced by periodontal disease. PMID:27799725

  18. Crosstalk between reticular adherens junctions and platelet endothelial cell adhesion molecule-1 regulates endothelial barrier function.

    PubMed

    Fernández-Martín, Laura; Marcos-Ramiro, Beatriz; Bigarella, Carolina L; Graupera, Mariona; Cain, Robert J; Reglero-Real, Natalia; Jiménez, Anaïs; Cernuda-Morollón, Eva; Correas, Isabel; Cox, Susan; Ridley, Anne J; Millán, Jaime

    2012-08-01

    Endothelial cells provide a barrier between the blood and tissues, which is reduced during inflammation to allow selective passage of molecules and cells. Adherens junctions (AJ) play a central role in regulating this barrier. We aim to investigate the role of a distinctive 3-dimensional reticular network of AJ found in the endothelium. In endothelial AJ, vascular endothelial-cadherin recruits the cytoplasmic proteins β-catenin and p120-catenin. β-catenin binds to α-catenin, which links AJ to actin filaments. AJ are usually described as linear structures along the actin-rich intercellular contacts. Here, we show that these AJ components can also be organized in reticular domains that contain low levels of actin. Reticular AJ are localized in areas where neighboring cells overlap and encompass the cell adhesion receptor platelet endothelial cell adhesion molecule-1 (PECAM-1). Superresolution microscopy revealed that PECAM-1 forms discrete structures distinct from and distributed along AJ, within the voids of reticular domains. Inflammatory tumor necrosis factor-α increases permeability by mechanisms that are independent of actomyosin-mediated tension and remain incompletely understood. Reticular AJ, but not actin-rich linear AJ, were disorganized by tumor necrosis factor-α. This correlated with PECAM-1 dispersal from cell borders. PECAM-1 inhibition with blocking antibodies or small interfering RNA specifically disrupted reticular AJ, leaving linear AJ intact. This disruption recapitulated typical tumor necrosis factor-α-induced alterations of barrier function, including increased β-catenin phosphorylation, without altering the actomyosin cytoskeleton. We propose that reticular AJ act coordinately with PECAM-1 to maintain endothelial barrier function in regions of low actomyosin-mediated tension. Selective disruption of reticular AJ contributes to permeability increase in response to tumor necrosis factor-α.

  19. Matrix MetalloProteinases (MMPs) andTissue Inhibitors of MetalloProteinases (TIMPs): positive and negative regulators intumor cell adhesion

    PubMed Central

    Bourboulia, Dimitra; Stetler-Stevenson, William G.

    2010-01-01

    Cells adhere to one another and/or to matrices that surround them. Regulation of cell-cell (intercellular) and cell-matrix adhesion is tightly controlled in normal cells, however, defects in cell adhesion are common in the majority of humancancers. Multilateral communication among tumor cells with the extracellular matrix (ECM) and neighbor cells is accomplished through adhesion molecules, ECM components, proteolytic enzymes and their endogenous inhibitors. There is sufficient evidence to suggest that reduced adherence is a tumor cell propertyengaged during tumor progression. Tumor cells acquire the ability to change shape, detach and easily move through spaces disorganizing the normal tissue architecture. This property is due to changes in expression levels of adhesion molecules and/or due to elevated levels of secreted proteolytic enzymes, including matrix metalloproteinases (MMPs). Among other roles, MMPsdegrade the ECMand, therefore, prepare the path for tumor cells to migrate, invade and spread to distant secondary areas, where they form metastasis. Tissue Inhibitors of Metalloproteinases or TIMPs control MMP activities and, therefore, minimize matrix degradation. Both MMPs and TIMPs are involved in tissue remodeling and decisively regulate tumor cell progression including tumor angiogenesis. In this review, we describe and discuss data that support the important role of MMPs and TIMPs in cancer cell adhesion and tumor progression. PMID:20470890

  20. Image-based quantification and mathematical modeling of spatial heterogeneity in ESC colonies.

    PubMed

    Herberg, Maria; Zerjatke, Thomas; de Back, Walter; Glauche, Ingmar; Roeder, Ingo

    2015-06-01

    Pluripotent embryonic stem cells (ESCs) have the potential to differentiate into cells of all three germ layers. This unique property has been extensively studied on the intracellular, transcriptional level. However, ESCs typically form clusters of cells with distinct size and shape, and establish spatial structures that are vital for the maintenance of pluripotency. Even though it is recognized that the cells' arrangement and local interactions play a role in fate decision processes, the relations between transcriptional and spatial patterns have not yet been studied. We present a systems biology approach which combines live-cell imaging, quantitative image analysis, and multiscale, mathematical modeling of ESC growth. In particular, we develop quantitative measures of the morphology and of the spatial clustering of ESCs with different expression levels and apply them to images of both in vitro and in silico cultures. Using the same measures, we are able to compare model scenarios with different assumptions on cell-cell adhesions and intercellular feedback mechanisms directly with experimental data. Applying our methodology to microscopy images of cultured ESCs, we demonstrate that the emerging colonies are highly variable regarding both morphological and spatial fluorescence patterns. Moreover, we can show that most ESC colonies contain only one cluster of cells with high self-renewing capacity. These cells are preferentially located in the interior of a colony structure. The integrated approach combining image analysis with mathematical modeling allows us to reveal potential transcription factor related cellular and intercellular mechanisms behind the emergence of observed patterns that cannot be derived from images directly. © 2015 International Society for Advancement of Cytometry.

  1. Crk1/2-dependent signaling is necessary for podocyte foot process spreading in mouse models of glomerular disease

    PubMed Central

    George, Britta; Verma, Rakesh; Soofi, Abdulsalam A.; Garg, Puneet; Zhang, Jidong; Park, Tae-Ju; Giardino, Laura; Ryzhova, Larisa; Johnstone, Duncan B.; Wong, Hetty; Nihalani, Deepak; Salant, David J.; Hanks, Steven K.; Curran, Tom; Rastaldi, Maria Pia; Holzman, Lawrence B.

    2012-01-01

    The morphology of healthy podocyte foot processes is necessary for maintaining the characteristics of the kidney filtration barrier. In most forms of glomerular disease, abnormal filter barrier function results when podocytes undergo foot process spreading and retraction by remodeling their cytoskeletal architecture and intercellular junctions during a process known as effacement. The cell adhesion protein nephrin is necessary for establishing the morphology of the kidney podocyte in development by transducing from the specialized podocyte intercellular junction phosphorylation-mediated signals that regulate cytoskeletal dynamics. The present studies extend our understanding of nephrin function by showing that nephrin activation in cultured podocytes induced actin dynamics necessary for lamellipodial protrusion. This process required a PI3K-, Cas-, and Crk1/2-dependent signaling mechanism distinct from the previously described nephrin-Nck1/2 pathway necessary for assembly and polymerization of actin filaments. Our present findings also support the hypothesis that mechanisms governing lamellipodial protrusion in culture are similar to those used in vivo during foot process effacement in a subset of glomerular diseases. In mice, podocyte-specific deletion of Crk1/2 prevented foot process effacement in one model of podocyte injury and attenuated foot process effacement and associated proteinuria in a delayed fashion in a second model. In humans, focal adhesion kinase and Cas phosphorylation — markers of focal adhesion complex–mediated Crk-dependent signaling — was induced in minimal change disease and membranous nephropathy, but not focal segmental glomerulosclerosis. Together, these observations suggest that activation of a Cas-Crk1/2–dependent complex is necessary for foot process effacement observed in distinct subsets of human glomerular diseases. PMID:22251701

  2. Endothelial targeting of high-affinity multivalent polymer nanocarriers directed to intercellular adhesion molecule 1.

    PubMed

    Muro, Silvia; Dziubla, Thomas; Qiu, Weining; Leferovich, John; Cui, Xiumin; Berk, Erik; Muzykantov, Vladimir R

    2006-06-01

    Targeting of diagnostic and therapeutic agents to endothelial cells (ECs) provides an avenue to improve treatment of many maladies. For example, intercellular adhesion molecule 1 (ICAM-1), a constitutive endothelial cell adhesion molecule up-regulated in many diseases, is a good determinant for endothelial targeting of therapeutic enzymes and polymer nanocarriers (PNCs) conjugated with anti-ICAM (anti-ICAM/PNCs). However, intrinsic and extrinsic factors that control targeting of anti-ICAM/PNCs to ECs (e.g., anti-ICAM affinity and PNC valency and flow) have not been defined. In this study we tested in vitro and in vivo parameters of targeting to ECs of anti-ICAM/PNCs consisting of either prototype polystyrene or biodegradable poly(lactic-coglycolic) acid polymers (approximately 200 nm diameter spheres carrying approximately 200 anti-ICAM molecules). Anti-ICAM/PNCs, but not control IgG/PNCs 1) rapidly (t1/2 approximately 5 min) and specifically bound to tumor necrosis factor-activated ECs in a dose-dependent manner (Bmax approximately 350 PNC/cell) at both static and physiological shear stress conditions and 2) bound to ECs and accumulated in the pulmonary vasculature after i.v. injection in mice. Anti-ICAM/PNCs displayed markedly higher EC affinity versus naked anti-ICAM (Kd approximately 80 pM versus approximately 8 nM) in cell culture and, probably because of this factor, higher value (185.3 +/- 24.2 versus 50.5 +/- 1.5% injected dose/g) and selectivity (lung/blood ratio 81.0 +/- 10.9 versus 2.1 +/- 0.02, in part due to faster blood clearance) of pulmonary targeting. These results 1) show that reformatting monomolecular anti-ICAM into high-affinity multivalent PNCs boosts their vascular immuno-targeting, which withstands physiological hydrodynamics and 2) support potential anti-ICAM/PNCs utility for medical applications.

  3. α-Enolase Causes Proinflammatory Activation of Pulmonary Microvascular Endothelial Cells and Primes Neutrophils Through Plasmin Activation of Protease-Activated Receptor 2.

    PubMed

    Bock, Ashley; Tucker, Nicole; Kelher, Marguerite R; Khan, Samina Y; Gonzalez, Eduardo; Wohlauer, Max; Hansen, Kirk; Dzieciatkowska, Monika; Sauaia, Angels; Banerjee, Anirban; Moore, Ernest E; Silliman, Christopher C

    2015-08-01

    Proinflammatory activation of vascular endothelium leading to increased surface expression of adhesion molecules and neutrophil (PMN) sequestration and subsequent activation is paramount in the development of acute lung injury and organ injury in injured patients. We hypothesize that α-enolase, which accumulates in injured patients, primes PMNs and causes proinflammatory activation of endothelial cells leading to PMN-mediated cytotoxicity. Proteomic analyses of field plasma samples from injured versus healthy patients were used for protein identification. Human pulmonary microvascular endothelial cells (HMVECs) were incubated with α-enolase or thrombin, and intercellular adhesion molecule-1 surface expression was measured by flow cytometry. A two-event in vitro model of PMN cytotoxicity HMVECs activated with α-enolase, thrombin, or buffer was used as targets for lysophosphatidylcholine-primed or buffer-treated PMNs. The PMN priming activity of α-enolase was completed, and lysates from both PMNs and HMVECs were immunoblotted for protease-activated receptor 1 (PAR-1) and PAR-2 and coprecipitation of α-enolase with PAR-2 and plasminogen/plasmin. α-Enolase increased 10.8-fold in injured patients (P < 0.05). Thrombin and α-enolase significantly increased intercellular adhesion molecule-1 surface expression on HMVECs, which was inhibited by antiproteases, induced PMN adherence, and served as the first event in the two-event model of PMN cytotoxicity. α-Enolase coprecipitated with PAR-2 and plasminogen/plasmin on HMVECs and PMNs and induced PMN priming, which was inhibited by tranexamic acid, and enzymatic activity was not required. α-Enolase increases after injury and may activate pulmonary endothelial cells and prime PMNs through plasmin activity and PAR-2 activation. Such proinflammatory endothelial activation may predispose to PMN-mediated organ injury.

  4. Regulation of Bacteria-Induced Intercellular Adhesion Molecule-1 by CCAAT/Enhancer Binding Proteins

    PubMed Central

    Manzel, Lori J.; Chin, Cecilia L.; Behlke, Mark A.; Look, Dwight C.

    2009-01-01

    Direct interaction between bacteria and epithelial cells may initiate or amplify the airway response through induction of epithelial defense gene expression by nuclear factor-κB (NF-κB). However, multiple signaling pathways modify NF-κB effects to modulate gene expression. In this study, the effects of CCAAT/enhancer binding protein (C/EBP) family members on induction of the leukocyte adhesion glycoprotein intercellular adhesion molecule-1 (ICAM-1) was examined in primary cultures of human tracheobronchial epithelial cells incubated with nontypeable Haemophilus influenzae. Increased ICAM-1 gene transcription in response to H. influenzae required gene sequences located at −200 to −135 in the 5′-flanking region that contain a C/EBP-binding sequence immediately upstream of the NF-κB enhancer site. Constitutive C/EBPβ was found to have an important role in epithelial cell ICAM-1 regulation, while the adjacent NF-κB sequence binds the RelA/p65 and NF-κB1/p50 members of the NF-κB family to induce ICAM-1 expression in response to H. influenzae. The expression of C/EBP proteins is not regulated by p38 mitogen-activated protein kinase activation, but p38 affects gene transcription by increasing the binding of TATA-binding protein to TATA-box–containing gene sequences. Epithelial cell ICAM-1 expression in response to H. influenzae was decreased by expressing dominant-negative protein or RNA interference against C/EBPβ, confirming its role in ICAM-1 regulation. Although airway epithelial cells express multiple constitutive and inducible C/EBP family members that bind C/EBP sequences, the results indicate that C/EBPβ plays a central role in modulation of NF-κB–dependent defense gene expression in human airway epithelial cells after exposure to H. influenzae. PMID:18703796

  5. Induction of mast cell accumulation by chymase via an enzymatic activity- and intercellular adhesion molecule-1-dependent mechanism.

    PubMed

    Zhang, Huiyun; Wang, Junling; Wang, Ling; Zhan, Mengmeng; Li, Shigang; Fang, Zeman; Xu, Ciyan; Zheng, Yanshan; He, Shaoheng

    2018-02-01

    Chymase is a unique, abundant secretory product of mast cells and a potent chemoattractant for eosinophils, monocytes and neutrophils, but little is known of its influence on mast cell accumulation. A mouse peritoneal inflammation model, cell migration assay and flowcytometry analysis, were used to investigate the role of chymase in recruiting mast cells. Chymase increased, by up to 5.4-fold, mast cell numbers in mouse peritoneum. Inhibitors of chymase, heat-inactivation of the enzyme, sodium cromoglycate and terfenadine, and pretreatment of mice with anti-intercellular adhesion molecule 1, anti-L-selectin, anti-CD11a and anti-CD18 antibodies dramatically diminished the chymase-induced increase in mast cell accumulation. These findings indicate that this effect of chymase is dependent on its enzymatic activity and activation of adhesion molecules. In addition, chymase provoked a significant increase in 5-HT and eotaxin release (up to 1.8- and 2.2-fold, respectively) in mouse peritoneum. Since 5-HT, eotaxin and RANTES can induce marked mast cell accumulation, these indirect mechanisms may also contribute to chymase-induced mast cell accumulation. Moreover, chymase increased the trans-endothelium migration of mast cells in vitro indicating it also acts as a chemoattractant. The finding that mast cells accumulate in response to chymase implies further that chymase is a major pro-inflammatory mediator of mast cells. This effect of chymase, a major product of mast cell granules, suggests a novel self-amplification mechanism for mast cell accumulation in allergic inflammation. Mast cell stabilizers and inhibitors of chymase may have potential as a treatment of allergic disorders. © 2017 The British Pharmacological Society.

  6. Measurement of leukocyte rheology in vascular disease: clinical rationale and methodology. International Society of Clinical Hemorheology.

    PubMed

    Wautier, J L; Schmid-Schönbein, G W; Nash, G B

    1999-01-01

    The measurement of leukocyte rheology in vascular disease is a recent development with a wide range of new opportunities. The International Society of Clinical Hemorheology has asked an expert panel to propose guidelines for the investigation of leukocyte rheology in clinical situations. This article first discusses the mechanical, adhesive and related functional properties of leukocytes (especially neutrophils) which influence their circulation, and establishes the rationale for clinically-related measurements of parameters which describe them. It is concluded that quantitation of leukocyte adhesion molecules, and of their endothelial receptors may assist understanding of leukocyte behaviour in vascular disease, along with measurements of flow resistance of leukocytes, free radical production, degranulation and gene expression. For instance, vascular cell adhesion molecule (VCAM-1) is abnormally present on endothelial cells in atherosclerosis, diabetes mellitus and inflammatory conditions. Soluble forms of intercellular adhesion molecule (ICAM-1) or VCAM can be found elevated in the blood of patients with rheumatoid arthritis or infections disease. In the second part of the article, possible technical approaches are presented and possible avenues for leukocyte rheological investigations are discussed.

  7. Drospirenone and levonorgestrel in combination with either 30 or 20 mcg ethinylestradiol reduce soluble adhesion molecules in Brazilian women; cross-sectional study.

    PubMed

    Stocco, Bianca; Fumagalli, Helen Figueiredo; Franceschini, Silvio Antônio; Martinez, Edson Zangiacomi; Marzocchi-Machado, Cleni Mara; Toloi, Maria Regina Torqueti

    2012-11-01

    The objective of this study was to evaluate the effect of three contraceptive pills containing ethinylestradiol (EE) (20 or 30 mcg) in combination with drospirenone (DRSP) and levonorgestrel (LNG) on plasma concentration of adhesion molecules vascular cell adhesion molecule -1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1) and E-selectin. A cross-sectional study was conducted with 72 participants (18-30 years old) distributed into three groups that used oral contraceptives containing EE 20 or 30 mcg combined with DRSP 3 mg or EE 30 mcg/LNG 150 mcg for at least 6 months. The control group was comprised of nonusers of contraceptives. Soluble VCAM-1, soluble ICAM-1 and soluble E-selectin were evaluated by enzyme-linked immunosorbent assay. Compared to the control group, a significant decrease was found in VCAM-1 and ICAM-1 concentrations with use of DRSP/20 EE and LNG/30 EE. DRSP/20 EE and LNG/30 EE induce favorable changes in endothelial function. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. Antiatherosclerotic effects of Artemisia princeps Pampanini cv. Sajabal in LDL receptor deficient mice.

    PubMed

    Han, Jong-Min; Kim, Min-Jung; Baek, Seung-Hwa; An, Sojin; Jin, Yue-Yan; Chung, Hae-Gon; Baek, Nam-In; Choi, Myung-Sook; Lee, Kyung-Tae; Jeong, Tae-Sook

    2009-02-25

    Antiatherosclerotic effects of ethanolic extracts of Artemisia princeps Pampanini cv. Sajabal (ESJ) were investigated in low-density lipoprotein receptor deficient (LDLR(-/-)) mice. The Western diet-induced high levels of total cholesterol and triglyceride were similar in the ESJ and control groups. However, circulating oxidized LDL was significantly decreased in the ESJ group (p < 0.05). ESJ also markedly decreased aortic expression levels of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1 beta (IL-1 beta), and reduced the aortic lesion formation and macrophage accumulation by 36.7% (p < 0.05) and 43% (p < 0.01) in the control group, respectively. Additionally, ESJ inhibited atherogenic properties with cytokine-induced surface expression of cell adhesion molecules, chemokines, and monocyte adhesion to the human umbilical vein endothelial cells (HUVECs), and simultaneously suppressed nuclear factor-kappaB (NF-kappaB) activation. These results suggest that ethanolic extracts of Artemisia princeps Pampanini cv. Sajabal contributes to the antiatherosclerotic and anti-inflammatory activities in LDLR(-/-) mice.

  9. 150(th) anniversary series: Desmosomes and autoimmune disease, perspective of dynamic desmosome remodeling and its impairments in pemphigus.

    PubMed

    Kitajima, Yasuo

    2014-12-01

    Desmosomes are the most important intercellular adhering junctions that adhere two adjacent keratinocytes directly with desmosomal cadherins, that is, desmogleins (Dsgs) and desmocollins, forming an epidermal sheet. Recently, two cell-cell adhesion states of desmosomes, that is, "stable hyper-adhesion" and "dynamic weak-adhesion" conditions have been recognized. They are mutually reversible through cell signaling events involving protein kinase C (PKC), Src and epidermal growth factor receptor (EGFR) during Ca(2+)-switching and wound healing. This remodeling is impaired in pemphigus vulgaris (PV, an autoimmune blistering disease), caused by anti-Dsg3 antibodies. The antibody binding to Dsg3 activates PKC, Src and EGFR, linked to generation of dynamic weak-adhesion desmosomes, followed by p38MAPK-mediated endocytosis of Dsg3, resulting in the specific depletion of Dsg3 from desmosomes and acantholysis. A variety of pemphigus outside-in signaling may explain different clinical (non-inflammatory, inflammatory, and necrolytic) types of pemphigus. Pemphigus could be referred to a "desmosome-remodeling disease involving pemphigus IgG-activated outside-in signaling events".

  10. Role of cell division and self-propulsion in self-organization of 2D cell co-cultures

    NASA Astrophysics Data System (ADS)

    Das, Moumita; Dey, Supravat; Wu, Mingming; Ma, Minglin

    Self-organization of cells is a key process in developmental and cancer biology. The differential adhesion hypothesis (DAH), which assumes cells as equilibrium liquid droplets and relates the self-assembly of cells to differences in inter-cellular adhesiveness, has been very successful in explaining cellular organization during morphogenesis where neighboring cells have the same non-equilibrium properties (motility, proliferation rate). However, recently it has been experimentally shown that for a co-culture of two different cell types proliferating at different rates, the resulting spatial morphologies cannot be explained using the DAH alone. Motivated by this, we develop and study a two-dimensional model of a cell co-culture that includes cell division and self-propulsion in addition to cell-cell adhesion, and systemically study how cells with significantly different adhesion, motility, and proliferation rate dynamically organize themselves in a spatiotemporal and context-dependent manner. Our results may help to understand how differential equilibrium and non-equilibrium properties cooperate and compete leading to different morphologies during tumor development, with important consequences for invasion and metastasis

  11. Structural basis for regulation of GPR56/ADGRG1 by its alternatively spliced extracellular domains

    PubMed Central

    Salzman, Gabriel S.; Ackerman, Sarah D.; Ding, Chen; Koide, Akiko; Leon, Katherine; Luo, Rong; Stoveken, Hannah M.; Fernandez, Celia G.; Tall, Gregory G.; Piao, Xianhua; Monk, Kelly R.; Koide, Shohei; Araç, Demet

    2016-01-01

    Summary Adhesion G-protein-coupled receptors (aGPCRs) play critical roles in diverse neurobiological processes including brain development, synaptogenesis, and myelination. aGPCRs have large alternatively spliced extracellular regions (ECRs) that likely mediate intercellular signaling; however, the precise roles of ECRs remain unclear. The aGPCR GPR56/ADGRG1 regulates both oligodendrocyte and cortical development. Accordingly, human GPR56 mutations cause myelination defects and brain malformations. Here, we determined the crystal structure of the GPR56 ECR, the first structure of any complete aGPCR ECR, in complex with an inverse-agonist monobody, revealing a GPCR-Autoproteolysis-Inducing domain and a previously unidentified domain that we term Pentraxin/Laminin/neurexin/sex-hormone-binding-globulin-Like (PLL). Strikingly, PLL domain deletion caused increased signaling and characterizes a GPR56 splice variant. Finally, we show that an evolutionarily conserved residue in the PLL domain is critical for oligodendrocyte development in vivo. Thus, our results suggest that the GPR56 ECR has unique and multifaceted regulatory functions, providing novel insights into aGPCR roles in neurobiology. PMID:27657451

  12. Regulation of T-lymphocyte motility, adhesion and de-adhesion by a cell surface mechanism directed by low density lipoprotein receptor-related protein 1 and endogenous thrombospondin-1.

    PubMed

    Talme, Toomas; Bergdahl, Eva; Sundqvist, Karl-Gösta

    2014-06-01

    T lymphocytes are highly motile and constantly reposition themselves between a free-floating vascular state, transient adhesion and migration in tissues. The regulation behind this unique dynamic behaviour remains unclear. Here we show that T cells have a cell surface mechanism for integrated regulation of motility and adhesion and that integrin ligands and CXCL12/SDF-1 influence motility and adhesion through this mechanism. Targeting cell surface-expressed low-density lipoprotein receptor-related protein 1 (LRP1) with an antibody, or blocking transport of LRP1 to the cell surface, perturbed the cell surface distribution of endogenous thrombospondin-1 (TSP-1) while inhibiting motility and potentiating cytoplasmic spreading on intercellular adhesion molecule 1 (ICAM-1) and fibronectin. Integrin ligands and CXCL12 stimulated motility and enhanced cell surface expression of LRP1, intact TSP-1 and a 130,000 MW TSP-1 fragment while preventing formation of a de-adhesion-coupled 110 000 MW TSP-1 fragment. The appearance of the 130 000 MW TSP-1 fragment was inhibited by the antibody that targeted LRP1 expression, inhibited motility and enhanced spreading. The TSP-1 binding site in the LRP1-associated protein, calreticulin, stimulated adhesion to ICAM-1 through intact TSP-1 and CD47. Shear flow enhanced cell surface expression of intact TSP-1. Hence, chemokines and integrin ligands up-regulate a dominant motogenic pathway through LRP1 and TSP-1 cleavage and activate an associated adhesion pathway through the LRP1-calreticulin complex, intact TSP-1 and CD47. This regulation of T-cell motility and adhesion makes pro-adhesive stimuli favour motile responses, which may explain why T cells prioritize movement before permanent adhesion.

  13. Role of atrial endothelial cells in the development of atrial fibrosis and fibrillation in response to pressure overload.

    PubMed

    Kume, Osamu; Teshima, Yasushi; Abe, Ichitaro; Ikebe, Yuki; Oniki, Takahiro; Kondo, Hidekazu; Saito, Shotaro; Fukui, Akira; Yufu, Kunio; Miura, Masahiro; Shimada, Tatsuo; Takahashi, Naohiko

    Monocyte chemoattractant protein-1 (MCP-1)-mediated inflammatory mechanisms have been shown to play a crucial role in atrial fibrosis induced by pressure overload. In the present study, we investigated whether left atrial endothelial cells would quickly respond structurally and functionally to pressure overload to trigger atrial fibrosis and fibrillation. Six-week-old male Sprague-Dawley rats underwent suprarenal abdominal aortic constriction (AAC) or a sham operation. By day 3 after surgery, macrophages were observed to infiltrate into the endocardium. The expression of MCP-1 and E-selectin in atrial endothelium and the expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and ED1 in left atrial tissue were enhanced. Atrial endothelial cells were irregularly hypertrophied with the disarrangement of lines of cells by scanning electron microscopy. Various-sized gap formations appeared along the border in atrial endothelial cells, and several macrophages were located just in the endothelial gap. Along with the development of heterogeneous interstitial fibrosis, interatrial conduction time was prolonged and the inducibility of atrial fibrillation by programmed extrastimuli was increased in the AAC rats compared to the sham-operated rats. Atrial endothelium responds rapidly to pressure overload by expressing adhesion molecules and MCP-1, which induce macrophage infiltration into the atrial tissues. These processes could be an initial step in the development of atrial remodeling for atrial fibrillation. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. FABP4 regulates eosinophil recruitment and activation in allergic airway inflammation.

    PubMed

    Ge, Xiao Na; Bastan, Idil; Dileepan, Mythili; Greenberg, Yana; Ha, Sung Gil; Steen, Kaylee A; Bernlohr, David A; Rao, Savita P; Sriramarao, P

    2018-04-26

    Fatty acid binding protein 4 (FABP4), a member of a family of lipid-binding proteins, is known to play a role in inflammation by virtue of its ability to regulate intracellular events such as lipid fluxes and signaling. Studies have indicated a pro-inflammatory role for FABP4 in allergic asthma, although its expression and function in eosinophils, the predominant inflammatory cells recruited to allergic airways, was not investigated. We examined expression of FABP4 in murine eosinophils and its role in regulating cell recruitment in vitro as well as in cockroach antigen (CRA)-induced allergic airway inflammation. CRA exposure led to airway recruitment of FABP4-expressing inflammatory cells, specifically eosinophils, in wild type (WT) mice. FABP4 expression in eosinophils was induced by TNF-α as well as IL-4 and IL-13. FABP4-deficient eosinophils exhibited markedly decreased cell spreading/formation of leading edges on vascular cell adhesion molecule-1 and significantly decreased adhesion to intercellular adhesion molecule-1 associated with reduced β2 integrin expression relative to WT cells. Further, FABP4-deficient eosinophils exhibited decreased migration, F-actin polymerization, calcium flux and ERK (1/2) phosphorylation in response to eotaxin-1. In vivo, CRA-challenged FABP4-deficient mice exhibited attenuated eosinophilia and significantly reduced airway inflammation (improved airway reactivity, lower IL-5, IL-13, TNFα and LTC4 levels, decreased airway structural changes) compared to WT mice. In conclusion, expression of FABP4 in eosinophils is induced during conditions of inflammation and plays a pro-inflammatory role in the development of allergic asthma by promoting eosinophil adhesion and migration and contributing to the development of various aspects of airway inflammation.

  15. The Prognostic Value of Soluble Intercellular Adhesion Molecule 1 Plasma Level in Children With Acute Lung Injury.

    PubMed

    Al-Biltagi, Mohammed A; Abo-Elezz, Ahmed Ahmed Abd ElBasset; Abu-Ela, Khaled Talaat; Suliman, Ghada Abudelmomen; Sultan, Tamer Gomaa Hassan

    2017-06-01

    The objective of this study was to evaluate the prognostic significance of soluble intercellular adhesion molecule 1 (sICAM-1) measurement in plasma for the prediction of outcome of acute lung injury (ALI) in children that may allow early recognition of critical cases. The study was performed as a prospective, controlled cohort study involving 40 children with ALI and 30 healthy children. The plasma level of sICAM-1 was measured at days 1 and 3 of development of ALI for the patient group and measured only once for the control group. C-Reactive protein was measured in both groups on day 1 only. There was significant increase in sICAM-1 in the patient group than in the control group ( P = .001*). The mortality rate reached 55% in children with ALI. The ceased group had significantly higher plasma sICAM-1 levels both at days 1 and 3 than the survived group ( P < .001*), and there was positive correlation between plasma sICAM-1 level and both duration of mechanical ventilation and the death rate, but more significant correlation was observed with plasma sICAM-1 levels at day 3 than day 1. Plasma sICAM-1 level served as a good predictor biomarker for both mechanical ventilation duration and the mortality risk in children with ALI.

  16. Correlation of serum intercellular adhesion molecule 1 and vascular endothelial growth factor with tumor grading and staging in breast cancer patients.

    PubMed

    Haghi, Alireza Rastgoo; Vahedi, Amir; Shekarchi, Ali Akbar; Kamran, Aziz

    2017-01-01

    Breast cancer is the most common cancer among women. There are several prognostic factors for this disease. The aim of this article is to explore the correlation of serum level of vascular endothelial growth factor (VEGF) and intercellular adhesion molecule 1 (ICAM1) with tumor, node, metastasis staging and grading of breast cancer. Serum samples of 51 patients with breast cancer were assessed with enzyme-linked immunosorbent assay for the level of VEGF and ICAM1 preoperatively. After the operation, histopathologic specimens stained with hematoxylin and eosin were evaluated for tumor size, histopathologic subtype, grade, lymph node, vascular and lymphatic involvement. Then, the correlation of tumor stage and grade and serum level of markers was analyzed. There was no significant correlation between serum level of markers with vascular invasions, lymph node involvement, and menstruation. There was a weak correlation between tumor size and serum level of ICAM1 with Pearson score correlation, but there was no significant correlation with VEGF. There was no significant correlation between tumor grading and staging with the level of markers. There was a significant correlation between the level of VEGF and ICAM1 and histologic type of tumors in invasive through in situ tumors. Levels of VEGF and ICAM1 can be used as a predictor of tumor invasion and also for target therapy.

  17. Neuroprotective and Blood-Retinal Barrier-Preserving Effects of Cannabidiol in Experimental Diabetes

    PubMed Central

    El-Remessy, Azza B.; Al-Shabrawey, Mohamed; Khalifa, Yousuf; Tsai, Nai-Tse; Caldwell, Ruth B.; Liou, Gregory I.

    2006-01-01

    Diabetic retinopathy is characterized by blood-retinal barrier (BRB) breakdown and neurotoxicity. These pathologies have been associated with oxidative stress and proinflammatory cytokines, which may operate by activating their downstream target p38 MAP kinase. In the present study, the protective effects of a nonpsychotropic cannabinoid, cannabidiol (CBD), were examined in streptozotocin-induced diabetic rats after 1, 2, or 4 weeks. Retinal cell death was determined by terminal dUTP nick-end labeling assay; BRB function by quantifying extravasation of bovine serum albumin-fluorescein; and oxidative stress by assays for lipid peroxidation, dichlorofluorescein fluorescence, and tyrosine nitration. Experimental diabetes induced significant increases in oxidative stress, retinal neuronal cell death, and vascular permeability. These effects were associated with increased levels of tumor necrosis factor-α, vascular endothelial growth factor, and intercellular adhesion molecule-1 and activation of p38 MAP kinase, as assessed by enzyme-linked immunosorbent assay, immunohistochemistry, and/or Western blot. CBD treatment significantly reduced oxidative stress; decreased the levels of tumor necrosis factor-α, vascular endothelial growth factor, and intercellular adhesion molecule-1; and prevented retinal cell death and vascular hyperpermeability in the diabetic retina. Consistent with these effects, CBD treatment also significantly inhibited p38 MAP kinase in the diabetic retina. These results demonstrate that CBD treatment reduces neurotoxicity, inflammation, and BRB breakdown in diabetic animals through activities that may involve inhibition of p38 MAP kinase. PMID:16400026

  18. Cocaine-associated retiform purpura: a C5b-9-mediated microangiopathy syndrome associated with enhanced apoptosis and high levels of intercellular adhesion molecule-1 expression.

    PubMed

    Magro, Cynthia M; Wang, Xuan

    2013-10-01

    Cocaine-associated retiform purpura is a recently described entity characterized by striking hemorrhagic necrosis involving areas of skin associated with administration of cocaine. Levamisole, an adulterant in cocaine, has been suggested as the main culprit pathogenetically. Four cases of cocaine-associated retiform purpura were encountered in the dermatopathology practice of C. M. Magro. The light microscopic findings were correlated with immunohistochemical and immunofluorescence studies. All 4 cases showed a very striking thrombotic diathesis associated with intravascular macrophage accumulation. Necrotizing vasculitis was noted in 1 case. Striking intercellular adhesion molecule-1 (ICAM-1)/CD54 expression in vessel wall along with endothelial expression of caspase 3 and extensive vascular C5b-9 deposition was observed in all biopsies examined. Cocaine-induced retiform purpura is a C5b-9-mediated microvascular injury associated with enhanced apoptosis and prominent vascular expression of ICAM-1, all of which have been shown in prior in vitro and in vivo murine models to be a direct effect of cocaine metabolic products. Antineutrophilic cytoplasmic antibody and antiphospholipid antibodies are likely the direct sequelae of the proapoptotic microenvironment. The inflammatory vasculitic lesion could reflect the downstream end point reflective of enhanced ICAM-1 expression and the development of antineutrophilic cytoplasmic antibody. Levamisole likely works synergistically with cocaine in the propagation of this syndromic complex.

  19. Expression of interleukin-8 and intercellular cell adhesion molecule-1 in the synovial membrane and cranial cruciate ligament of dogs after rupture of the ligament

    PubMed Central

    El-Hadi, Mustafa; Charavaryamath, Chandarshekhar; Aebischer, Andrea; Smith, C. Wayne; Shmon, Cindy; Singh, Baljit

    2012-01-01

    This cross-sectional clinical study compared inflammation, including expression of the chemokine interleukin (IL)-8 and intercellular cell adhesion molecule-1 (ICAM-1), in the stifle joints of 4 control dogs and 23 dogs with cranial cruciate ligament rupture (CCLR). The CCL, synovial membrane, meniscus, cartilage, and synovial fluid from the affected stifle joints of all the dogs were examined. Inflammatory cell counts were performed on the synovial fluid, and the tissues were processed for histologic study and immunohistochemical detection of IL-8 and ICAM-1. The synovial fluid from the stifle joints of the dogs with CCLR had an increased percentage of neutrophils (P = 0.054) and a decreased percentage of lymphocytes (P = 0.004) but not macrophages compared with the fluid from the control dogs. There was accumulation of inflammatory cells and increased expression of IL-8 and ICAM-1 in the vascular endothelium of the synovial membrane and the CCL of the dogs with CCLR. The increase in inflammatory cells in the stifle joints of dogs with CCLR may therefore be due to increased expression of IL-8 and ICAM-1 in the synovial membrane and the CCL after the injury. These data may help in understanding the mechanisms of inflammation associated with CCLR. PMID:22754089

  20. Expression of interleukin-8 and intercellular cell adhesion molecule-1 in the synovial membrane and cranial cruciate ligament of dogs after rupture of the ligament.

    PubMed

    El-Hadi, Mustafa; Charavaryamath, Chandarshekhar; Aebischer, Andrea; Smith, C Wayne; Shmon, Cindy; Singh, Baljit

    2012-01-01

    This cross-sectional clinical study compared inflammation, including expression of the chemokine interleukin (IL)-8 and intercellular cell adhesion molecule-1 (ICAM-1), in the stifle joints of 4 control dogs and 23 dogs with cranial cruciate ligament rupture (CCLR). The CCL, synovial membrane, meniscus, cartilage, and synovial fluid from the affected stifle joints of all the dogs were examined. Inflammatory cell counts were performed on the synovial fluid, and the tissues were processed for histologic study and immunohistochemical detection of IL-8 and ICAM-1. The synovial fluid from the stifle joints of the dogs with CCLR had an increased percentage of neutrophils (P = 0.054) and a decreased percentage of lymphocytes (P = 0.004) but not macrophages compared with the fluid from the control dogs. There was accumulation of inflammatory cells and increased expression of IL-8 and ICAM-1 in the vascular endothelium of the synovial membrane and the CCL of the dogs with CCLR. The increase in inflammatory cells in the stifle joints of dogs with CCLR may therefore be due to increased expression of IL-8 and ICAM-1 in the synovial membrane and the CCL after the injury. These data may help in understanding the mechanisms of inflammation associated with CCLR.

  1. Dynamic pattern of endothelial cell adhesion molecule expression in muscle and perineural vessels from patients with classic polyarteritis nodosa.

    PubMed

    Coll-Vinent, B; Cebrián, M; Cid, M C; Font, C; Esparza, J; Juan, M; Yagüe, J; Urbano-Márquez, A; Grau, J M

    1998-03-01

    To investigate endothelial cell adhesion molecule expression in vessels from patients with classic polyarteritis nodosa (PAN). Frozen sections of 21 muscle and 16 nerve samples from 30 patients with biopsy-proven PAN and 12 histologically normal muscle and 2 histologically normal nerve samples from 12 controls were studied immunohistochemically, using specific monoclonal antibodies (MAb) that recognize adhesion molecules. Adhesion molecules identified were intercellular adhesion molecule 1 (ICAM-1), ICAM-2, ICAM-3, vascular cell adhesion molecule 1 (VCAM-1), platelet endothelial cell adhesion molecule 1 (PECAM-1), E-selectin, P-selectin, L-selectin, lymphocyte function-associated antigen 1 (LFA-1), and very late activation antigen 4 (VLA-4). Neutrophils were identified with a MAb recognizing neutrophil elastase. Endothelial cells were identified with the lectin ulex europaeus. In early lesions, expression of PECAM-1, ICAM-1, ICAM-2, and P-selectin was similar to that in control samples, and VCAM-1 and E-selectin were induced in vascular endothelium. In advanced lesions, immunostaining for adhesion molecules diminished or disappeared in luminal endothelium, whereas these molecules were clearly expressed in microvessels within and surrounding inflamed vessels. Staining in endothelia from vessels in a healing stage tended to be negative. A high proportion of infiltrating leukocytes expressed LFA-1 and VLA-4, and only a minority expressed L-selectin. No relationship between the expression pattern of adhesion molecules and clinical features, disease duration, or previous corticosteroid treatment was observed. Endothelial adhesion molecule expression in PAN is a dynamic process that varies according to the histopathologic stage of the vascular lesions. The preferential expression of constitutive and inducible adhesion molecules in microvessels suggests that angiogenesis contributes to the persistence of inflammatory infiltration in PAN.

  2. Decoy receptor 3 promotes cell adhesion and enhances endometriosis development.

    PubMed

    Tsai, Hsiao-Wen; Huang, Ming-Ting; Wang, Peng-Hui; Huang, Ben-Shian; Chen, Yi-Jen; Hsieh, Shie-Liang

    2018-02-01

    Endometriosis is a multifactorial inflammatory disease with persistent activation of the nuclear factor-κB (NF-κB) signalling pathway. Aberrant adhesion of endometrium is the essential step in the progression of endometriosis, but the molecular mechanism of ectopic growth of endometrium is still unclear. Decoy receptor 3 (DcR3)/TNFRSF6B, a pleiotropic immunomodulator regulated by oestrogen, is able to activate focal adhesion kinase to promote cell adhesion. We found that DcR3 is upregulated in human ectopic endometrial cells via activation of the Akt-NF-κB signalling pathway, and its expression level correlates positively with that of the adhesion molecules intercellular adhesion molecule 1 (ICAM-1) and homing cell adhesion molecule (HCAM; CD44). In a multivariate regression model, DcR3 expression level was the most significant parameter associated with endometriosis severity. Knockdown of DcR3 not only downregulated the expression of ICAM-1 and HCAM, but also reduced cell adhesion and migration. In vivo investigation further showed that DcR3 promoted the growth and spread of endometrium, whereas knockdown of DcR3 by lentivirus-delivered short hairpin RNA inhibited ectopic adhesion of endometrium and abrogated endometriosis progression. These observations are in support of DcR3 playing a critical role in the pathogenesis of endometriosis, and the inhibition of DcR3 expression being a promising approach for the treatment of endometriosis. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  3. Inhibitory effects of clotrimazole on TNF-alpha-induced adhesion molecule expression and angiogenesis.

    PubMed

    Thapa, Dinesh; Lee, Jong Suk; Park, Min-A; Cho, Mi-Yeon; Park, Young-Joon; Choi, Han Gon; Jeong, Tae Cheon; Kim, Jung-Ae

    2009-04-01

    Cell adhesion molecules play a pivotal role in chronic inflammation and pathological angiogenesis. In the present study, we investigated the inhibitory effects of clotrimazole (CLT) on tumor necrosis factor (TNF)-alpha-induced changes in adhesion molecule expression. CLT dose-dependently inhibited monocyte chemoattractant protein-1 (MCP-1), intercellular cell adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) expressions in TNF-alpha-stimulated HT29 colonic epithelial cells. This inhibitory action of CLT correlated with a significant reduction in TNF-alpha-induced adhesion of monocytes to HT29 cells, which was comparable to the inhibitory effects of anti-ICAM-1 and VCAM-1 monoclonal antibodies on monocyte-epithelial adhesion. These inhibitory actions of CLT were, at least in part, attributable to the inhibition of redox sensitive NF-kappaB activation, as CLT inhibited TNF-alpha-induced ROS generation as well as NF-kappaB nuclear translocation and activation in HT29 cells. Furthermore, the inhibition of TNF-alpha-induced monocyte adhesion was also mimicked by the specific NF-kappaB inhibitor, pyrrolidine dithiocarbamate (PDTC). Inflammatory mediators including TNF-alpha have known to promote angiogenesis, which in turn further contributes to inflammatory pathology. Therefore, we additionally evaluated whether CLT modulates TNF-alpha-induced angiogenesis using in vivo chick chorioallantoic membrane (CAM) assay. The CAM assay showed that CLT dose-dependently attenuated TNF-alpha-induced angiogenesis, and the effect was correlated with decreased inflammation of the CAM tissue. In conclusion, our results suggest that CLT can inhibit TNF-alpha-triggered expression of adhesion molecules, ICAM-1 and VCAM-1, and angiogenesis during inflammation.

  4. Diversity of olfactomedin proteins in the sea urchin.

    PubMed

    Hillier, Brian J; Moy, Gary W; Vacquier, Victor D

    2007-06-01

    Olfactomedin (OLF) domain proteins maintain extracellular protein-protein interactions in diverse phyla. Only one OLF family member, amassin-1, has been described from the sea urchin Strongylocentrotus purpuratus, a basal invertebrate deuterostome. Amassin-1 mediates intercellular adhesion of coelomocytes (immunocytes). Here we describe the protein structural features of four additional OLF proteins, the total for the genome being five. Phylogenetically, four of these proteins (the amassins) form a subgroup among previously identified OLF proteins. The fifth OLF protein is within the colmedin subfamily and contains a type II transmembrane domain, collagen repeats, and an OLF domain. Sea urchin OLF proteins represent an intermediate diversification between protostomes and vertebrates. Transcripts of all five OLF family members are in coelomocytes and adult radial nerve tissue. Transcripts for some OLF proteins increase during late larval stages. Transcript levels for amassin-1 increase 1,000,000-fold, coinciding with formation of the adult urchin rudiment within the larval body.

  5. Identification of New Factors Modulating Adhesion Abilities of the Pioneer Commensal Bacterium Streptococcus salivarius

    PubMed Central

    Couvigny, Benoit; Kulakauskas, Saulius; Pons, Nicolas; Quinquis, Benoit; Abraham, Anne-Laure; Meylheuc, Thierry; Delorme, Christine; Renault, Pierre; Briandet, Romain; Lapaque, Nicolas; Guédon, Eric

    2018-01-01

    Biofilm formation is crucial for bacterial community development and host colonization by Streptococcus salivarius, a pioneer colonizer and commensal bacterium of the human gastrointestinal tract. This ability to form biofilms depends on bacterial adhesion to host surfaces, and on the intercellular aggregation contributing to biofilm cohesiveness. Many S. salivarius isolates auto-aggregate, an adhesion process mediated by cell surface proteins. To gain an insight into the genetic factors of S. salivarius that dictate host adhesion and biofilm formation, we developed a screening method, based on the differential sedimentation of bacteria in semi-liquid conditions according to their auto-aggregation capacity, which allowed us to identify twelve mutations affecting this auto-aggregation phenotype. Mutations targeted genes encoding (i) extracellular components, including the CshA surface-exposed protein, the extracellular BglB glucan-binding protein, the GtfE, GtfG and GtfH glycosyltransferases and enzymes responsible for synthesis of cell wall polysaccharides (CwpB, CwpK), (ii) proteins responsible for the extracellular localization of proteins, such as structural components of the accessory SecA2Y2 system (Asp1, Asp2, SecA2) and the SrtA sortase, and (iii) the LiaR transcriptional response regulator. These mutations also influenced biofilm architecture, revealing that similar cell-to-cell interactions govern assembly of auto-aggregates and biofilm formation. We found that BglB, CshA, GtfH and LiaR were specifically associated with bacterial auto-aggregation, whereas Asp1, Asp2, CwpB, CwpK, GtfE, GtfG, SecA2 and SrtA also contributed to adhesion to host cells and host-derived components, or to interactions with the human pathogen Fusobacterium nucleatum. Our study demonstrates that our screening method could also be used to identify genes implicated in the bacterial interactions of pathogens or probiotics, for which aggregation is either a virulence trait or an advantageous feature, respectively. PMID:29515553

  6. Baicalin Inhibits IL-17-Mediated Joint Inflammation in Murine Adjuvant-Induced Arthritis

    PubMed Central

    Yang, Xue; Yang, Ji; Zou, Hejian

    2013-01-01

    T-helper-17 (Th17) cells are implicated in a number of inflammatory disorders including rheumatoid arthritis. Antagonism of Th17 cells is a treatment option for arthritis. Here, we report that Baicalin, a compound isolated from the Chinese herb Huangqin (Scutellaria baicalensis Georgi), relieved ankle swelling and protected the joint against inflammatory destruction in a murine adjuvant-induced arthritis model. Baicalin inhibited splenic Th17 cell population expansion in vivo. Baicalin prevented interleukin- (IL-) 17-mediated lymphocyte adhesion to cultured synoviocytes. Baicalin also blocked IL-17-induced intercellular adhesion molecule 1, vascular cell adhesion molecule 1, IL-6, and tumor necrosis factor-alpha mRNA expression in cultured synoviocytes. Collectively, these findings suggest that Baicalin downregulates the joint inflammation caused by IL-17, which is likely produced by an expanded population of splenic Th17 cells in experimental arthritis. Baicalin might be a promising novel therapeutic agent for treating rheumatoid arthritis in humans. PMID:23840239

  7. Role of platelet adhesion in homeostasis and immunopathology.

    PubMed Central

    Männel, D N; Grau, G E

    1997-01-01

    Various molecules expressed on the surface of platelets have been shown to mediate the protective or deleterious role of these cells in immuno-inflammatory mechanisms. Increasing evidence points to the involvement of the cell adhesion molecules, gpIIb-IIIa, P-selectin, CD31, LFA-1, and CD36 in the interaction between platelets and endothelial cells as well as other cell types. The possible role of these molecules in the ability of platelets to support endothelium and to protect against tumour necrosis factor mediated cytolysis or parasitic invasion are reviewed. The involvement of platelets as effectors of tissue damage in cerebral malaria, lipopolysaccharide induced pathology, and pulmonary fibrosis is also discussed. This has then been extended to include the intercellular mechanisms underpinning their pathogenic role in metastasis, transplant rejection, stroke, brain hypoxia, and related conditions. A better understanding of the complex regulation and hierarchical organisation of these various platelet adhesion molecules may prove useful in the development of new approaches to the treatment of such diseases. Images PMID:9350300

  8. [Recent research advance on bone marrow microenvironment-mediated leukemia drug resistant mechanism].

    PubMed

    Fu, Bing; Ling, Yan-Juan

    2011-06-01

    The bone marrow microenvironment consists of bone marrow stromal cells, osteoblasts and osteoclasts which facilities the survival, differentiation and proliferation of hematopoietic cells through secreting soluble factors and extracellular matrix proteins that mediate these functions. This environment not only supports the growth of normal and malignant hematopoietic cells, but also protects them against the damage from chemotherapeutic agents through the secretion of soluble cytokines, cell adhesion, up-regulation of resistant genes and changes of cell cycle. In this review, the research advances on drug-resistance mechanisms mediated by bone marrow microenvironment are summarized briefly, including soluble factors mediating drug resistance, intercellular adhesion inducing drug resistance, up-regulation of some drug resistance genes, regulation in metabolism of leukemic cells, changes in cell cycles of tumor cells and so on.

  9. A systems biology approach to study systemic inflammation.

    PubMed

    Chen, Bor-Sen; Wu, Chia-Chou

    2014-01-01

    Systemic inflammation needs a precise control on the sequence and magnitude of occurring events. The high throughput data on the host-pathogen interactions gives us an opportunity to have a glimpse on the systemic inflammation. In this article, a dynamic Candida albicans-zebrafish interactive infectious network is built as an example to demonstrate how systems biology approach can be used to study systematic inflammation. In particular, based on microarray data of C. albicans and zebrafish during infection, the hyphal growth, zebrafish, and host-pathogen intercellular PPI networks were combined to form an integrated infectious PPI network that helps us understand the systematic mechanisms underlying the pathogenicity of C. albicans and the immune response of the host. The signaling pathways for morphogenesis and hyphal growth of C. albicans were 2 significant interactions found in the intercellular PPI network. Two cellular networks were also developed corresponding to the different infection stages (adhesion and invasion), and then compared with each other to identify proteins to gain more insight into the pathogenic role of hyphal development in the C. albicans infection process. Important defense-related proteins in zebrafish were predicted using the same approach. This integrated network consisting of intercellular invasion and cellular defense processes during infection can improve medical therapies and facilitate development of new antifungal drugs.

  10. Integrin β4 Signaling Promotes Mammary Tumor Cell Adhesion to Brain Microvascular Endothelium by Inducing ErbB2-mediated Secretion of VEGF

    PubMed Central

    Fan, Jie; Cai, Bin; Zeng, Min; Hao, Yanyan

    2015-01-01

    Prior studies have indicated that the β4 integrin promotes mammary tumor invasion and metastasis by combining with ErbB2 and amplifying its signaling capacity. However, the effector pathways and cellular functions by which the β4 integrin exerts these effects are incompletely understood. To examine if β4 signaling plays a role during mammary tumor cell adhesion to microvascular endothelium, we have examined ErbB2-transformed mammary tumor cells expressing either a wild-type (WT) or a signaling-defective form of β4 (1355T). We report that WT cells adhere to brain microvascular endothelium in vitro to a significantly larger extent as compared to 1355T cells. Interestingly, integrin β4 signaling does not exert a direct effect on adhesion to the endothelium or the underlying basement membrane. Rather, it enhances ErbB2-dependent expression of VEGF by tumor cells. VEGF in turn disrupts the tight and adherens junctions of endothelial monolayers, enabling the exposure of underlying basement membrane and increasing the adhesion of tumor cells to the intercellular junctions of endothelium. Inhibition of ErbB2 on tumor cells or the VEGFR-2 on endothelial cells suppresses mammary tumor cell adhesion to microvascular endothelium. Our results indicate that β4 signaling regulates VEGF expression by the mammary tumor cells thereby enhancing their adhesion to microvascular endothelium. PMID:21556948

  11. Involvement of leucocyte/endothelial cell interactions in anorexia nervosa.

    PubMed

    Víctor, Víctor M; Rovira-Llopis, Susana; Saiz-Alarcón, Vanessa; Sangüesa, Maria C; Rojo-Bofill, Luis; Bañuls, Celia; de Pablo, Carmen; Álvarez, Ángeles; Rojo, Luis; Rocha, Milagros; Hernández-Mijares, Antonio

    2015-07-01

    Anorexia nervosa is a common psychiatric disorder in adolescence and is related to cardiovascular complications. Our aim was to study the effect of anorexia nervosa on metabolic parameters, leucocyte-endothelium interactions, adhesion molecules and proinflammatory cytokines. This multicentre, cross-sectional, case-control study employed a population of 24 anorexic female patients and 36 controls. We evaluated anthropometric and metabolic parameters, interactions between leucocytes polymorphonuclear neutrophils (PMN) and human umbilical vein endothelial cells (HUVEC), proinflammatory cytokines such as tumour necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) and soluble cellular adhesion molecules (CAMs) including E-selectin, vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1). Anorexia nervosa was related to a decrease in weight, body mass index, waist circumference, systolic blood pressure, glucose, insulin and HOMA-IR, and an increase in HDL cholesterol. These effects disappeared after adjusting for BMI. Anorexia nervosa induced a decrease in PMN rolling velocity and an increase in PMN rolling flux and PMN adhesion. Increases in IL-6 and TNF-α and adhesion molecule VCAM-1 were also observed. This study supports the hypothesis of an association between anorexia nervosa, inflammation and the induction of leucocyte-endothelium interactions. These findings may explain, in part at least, the increased risk of vascular disease among patients with anorexia nervosa. © 2015 Stichting European Society for Clinical Investigation Journal Foundation.

  12. Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs): Positive and negative regulators in tumor cell adhesion.

    PubMed

    Bourboulia, Dimitra; Stetler-Stevenson, William G

    2010-06-01

    Cells adhere to one another and/or to matrices that surround them. Regulation of cell-cell (intercellular) and cell-matrix adhesion is tightly controlled in normal cells, however, defects in cell adhesion are common in the majority of human cancers. Multilateral communication among tumor cells with the extracellular matrix (ECM) and neighbor cells is accomplished through adhesion molecules, ECM components, proteolytic enzymes and their endogenous inhibitors. There is sufficient evidence to suggest that reduced adherence is a tumor cell property engaged during tumor progression. Tumor cells acquire the ability to change shape, detach and easily move through spaces disorganizing the normal tissue architecture. This property is due to changes in expression levels of adhesion molecules and/or due to elevated levels of secreted proteolytic enzymes, including matrix metalloproteinases (MMPs). Among other roles, MMPs degrade the ECM and, therefore, prepare the path for tumor cells to migrate, invade and spread to distant secondary areas, where they form metastasis. Tissue inhibitors of metalloproteinases or TIMPs control MMP activities and, therefore, minimize matrix degradation. Both MMPs and TIMPs are involved in tissue remodeling and decisively regulate tumor cell progression including tumor angiogenesis. In this review, we describe and discuss data that support the important role of MMPs and TIMPs in cancer cell adhesion and tumor progression. Published by Elsevier Ltd.

  13. Extracellular ultrathin fibers sensitive to intracellular reactive oxygen species: Formation of intercellular membrane bridges

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jung, Se-Hui; Park, Jin-Young; Joo, Jung-Hoon

    2011-07-15

    Membrane bridges are key cellular structures involved in intercellular communication; however, dynamics for their formation are not well understood. We demonstrated the formation and regulation of novel extracellular ultrathin fibers in NIH3T3 cells using confocal and atomic force microscopy. At adjacent regions of neighboring cells, phorbol 12-myristate 13-acetate (PMA) and glucose oxidase induced ultrathin fiber formation, which was prevented by Trolox, a reactive oxygen species (ROS) scavenger. The height of ROS-sensitive ultrathin fibers ranged from 2 to 4 nm. PMA-induced formation of ultrathin fibers was inhibited by cytochalasin D, but not by Taxol or colchicine, indicating that ultrathin fibers mainlymore » comprise microfilaments. PMA-induced ultrathin fibers underwent dynamic structural changes, resulting in formation of intercellular membrane bridges. Thus, these fibers are formed by a mechanism(s) involving ROS and involved in formation of intercellular membrane bridges. Furthermore, ultrastructural imaging of ultrathin fibers may contribute to understanding the diverse mechanisms of cell-to-cell communication and the intercellular transfer of biomolecules, including proteins and cell organelles.« less

  14. Desmosome Assembly and Disassembly Are Membrane Raft-Dependent

    PubMed Central

    Faundez, Victor; Koval, Michael; Mattheyses, Alexa L.; Kowalczyk, Andrew P.

    2014-01-01

    Strong intercellular adhesion is critical for tissues that experience mechanical stress, such as the skin and heart. Desmosomes provide adhesive strength to tissues by anchoring desmosomal cadherins of neighboring cells to the intermediate filament cytoskeleton. Alterations in assembly and disassembly compromise desmosome function and may contribute to human diseases, such as the autoimmune skin blistering disease pemphigus vulgaris (PV). We previously demonstrated that PV auto-antibodies directed against the desmosomal cadherin desmoglein 3 (Dsg3) cause loss of adhesion by triggering membrane raft-mediated Dsg3 endocytosis. We hypothesized that raft membrane microdomains play a broader role in desmosome homeostasis by regulating the dynamics of desmosome assembly and disassembly. In human keratinocytes, Dsg3 is raft associated as determined by biochemical and super resolution immunofluorescence microscopy methods. Cholesterol depletion, which disrupts rafts, prevented desmosome assembly and adhesion, thus functionally linking rafts to desmosome formation. Interestingly, Dsg3 did not associate with rafts in cells lacking desmosomal proteins. Additionally, PV IgG-induced desmosome disassembly occurred by redistribution of Dsg3 into raft-containing endocytic membrane domains, resulting in cholesterol-dependent loss of adhesion. These findings demonstrate that membrane rafts are required for desmosome assembly and disassembly dynamics, suggesting therapeutic potential for raft targeting agents in desmosomal diseases such as PV. PMID:24498201

  15. Trpm7 Protein Contributes to Intercellular Junction Formation in Mouse Urothelium*

    PubMed Central

    Watanabe, Masaki; Suzuki, Yoshiro; Uchida, Kunitoshi; Miyazaki, Naoyuki; Murata, Kazuyoshi; Matsumoto, Seiji; Kakizaki, Hidehiro; Tominaga, Makoto

    2015-01-01

    Trpm7 is a divalent cation-permeable channel that has been reported to be involved in magnesium homeostasis as well as cellular adhesion and migration. We generated urothelium-specific Trpm7 knock-out (KO) mice to reveal the function of Trpm7 in vivo. A Trpm7 KO was induced by tamoxifen and was confirmed by genomic PCR and immunohistochemistry. By using patch clamp recordings in primary urothelial cells, we observed that Mg2+-inhibitable cation currents as well as acid-inducible currents were significantly smaller in Trpm7 KO urothelial cells than in cells from control mice. Assessment of voiding behavior indicated a significantly smaller voided volume in Trpm7 KO mice (mean voided volume 0.28 ± 0.08 g in KO mice and 0.36 ± 0.04 g in control mice, p < 0.05, n = 6–8). Histological analysis showed partial but substantial edema in the submucosal layer of Trpm7 KO mice, most likely due to inflammation. The expression of proinflammatory cytokines TNF-α and IL-1β was significantly higher in Trpm7 KO bladders than in controls. In transmission electron microscopic analysis, immature intercellular junctions were observed in Trpm7 KO urothelium but not in control mice. These results suggest that Trpm7 is involved in the formation of intercellular junctions in mouse urothelium. Immature intercellular junctions in Trpm7 knock-out mice might lead to a disruption of barrier function resulting in inflammation and hypersensitive bladder afferent nerves that may affect voiding behavior in vivo. PMID:26504086

  16. Trpm7 Protein Contributes to Intercellular Junction Formation in Mouse Urothelium.

    PubMed

    Watanabe, Masaki; Suzuki, Yoshiro; Uchida, Kunitoshi; Miyazaki, Naoyuki; Murata, Kazuyoshi; Matsumoto, Seiji; Kakizaki, Hidehiro; Tominaga, Makoto

    2015-12-11

    Trpm7 is a divalent cation-permeable channel that has been reported to be involved in magnesium homeostasis as well as cellular adhesion and migration. We generated urothelium-specific Trpm7 knock-out (KO) mice to reveal the function of Trpm7 in vivo. A Trpm7 KO was induced by tamoxifen and was confirmed by genomic PCR and immunohistochemistry. By using patch clamp recordings in primary urothelial cells, we observed that Mg(2+)-inhibitable cation currents as well as acid-inducible currents were significantly smaller in Trpm7 KO urothelial cells than in cells from control mice. Assessment of voiding behavior indicated a significantly smaller voided volume in Trpm7 KO mice (mean voided volume 0.28 ± 0.08 g in KO mice and 0.36 ± 0.04 g in control mice, p < 0.05, n = 6-8). Histological analysis showed partial but substantial edema in the submucosal layer of Trpm7 KO mice, most likely due to inflammation. The expression of proinflammatory cytokines TNF-α and IL-1β was significantly higher in Trpm7 KO bladders than in controls. In transmission electron microscopic analysis, immature intercellular junctions were observed in Trpm7 KO urothelium but not in control mice. These results suggest that Trpm7 is involved in the formation of intercellular junctions in mouse urothelium. Immature intercellular junctions in Trpm7 knock-out mice might lead to a disruption of barrier function resulting in inflammation and hypersensitive bladder afferent nerves that may affect voiding behavior in vivo. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. ILK mediates LPS-induced vascular adhesion receptor expression and subsequent leucocyte trans-endothelial migration.

    PubMed

    Hortelano, Sonsoles; López-Fontal, Raquel; Través, Paqui G; Villa, Natividad; Grashoff, Carsten; Boscá, Lisardo; Luque, Alfonso

    2010-05-01

    The inflammatory response to injurious agents is tightly regulated to avoid adverse consequences of inappropriate leucocyte accumulation or failed resolution. Lipopolysaccharide (LPS)-activated endothelium recruits leucocytes to the inflamed tissue through controlled expression of membrane-associated adhesion molecules. LPS responses in macrophages are known to be regulated by integrin-linked kinase (ILK); in this study, we investigated the role of ILK in the regulation of the LPS-elicited inflammatory response in endothelium. This study was performed on immortalized mouse endothelial cells (EC) isolated from lung and coronary vasculature. Cells were thoroughly characterized and the role of ILK in the regulation of the LPS response was investigated by suppressing ILK expression using siRNA and shRNA technologies. Phenotypic and functional analyses confirmed that the immortalized cells behaved as true EC. LPS induced the expression of the inflammatory genes E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). ILK knockdown impaired LPS-mediated endothelial activation by preventing the induction of ICAM-1 and VCAM-1. Blockade of the LPS-induced response inhibited the inflammatory-related processes of firm adhesion and trans-endothelial migration of leucocytes. ILK is involved in the expression of cell adhesion molecules by EC activated with the inflammatory stimulus LPS. This reduced expression modulates leucocyte adhesion to the endothelium and the extravasation process. This finding suggests ILK as a potential anti-inflammatory target for the development of vascular-specific treatments for inflammation-related diseases.

  18. Adhesion of Epstein–Barr virus-positive natural killer cell lines to cultured endothelial cells stimulated with inflammatory cytokines

    PubMed Central

    Kanno, H; Watabe, D; Shimizu, N; Sawai, T

    2008-01-01

    Chronic active Epstein–Barr virus (EBV) infection (CAEBV) is characterized by chronic recurrent infectious mononucleosis-like symptoms. Approximately one-fourth of CAEBV patients develop vascular lesions with infiltration of EBV-positive lymphoid cells. Furthermore, EBV-positive natural killer (NK)/T cell lymphomas often exhibit angiocentric or angiodestructive lesions. These suggest an affinity of EBV-positive NK/T cells to vascular components. In this study, we evaluated the expression of adhesion molecules and cytokines in EBV-positive NK lymphoma cell lines, SNK1 and SNK6, and examined the role of cytokines in the interaction between NK cell lines and endothelial cells. SNKs expressed intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) at much higher levels than those in EBV-negative T cell lines. SNKs produced the larger amount of tumour necrosis factor (TNF)-α, which caused increased expression of ICAM-1 and VCAM-1 in cultured human endothelial cells, than that from EBV-negative T cell lines. Furthermore, SNKs exhibited increased adhesion to cultured endothelial cells stimulated with TNF-α or interleukin (IL)-1β, and the pretreatment of cytokine-stimulated endothelial cells with anti-VCAM-1-antibodies reduced cell adhesion. These indicate that the up-regulated expression of VCAM-1 on cytokine-stimulated endothelial cells would be important for the adhesion of EBV-positive NK cells and might initiate the vascular lesions. PMID:18190605

  19. XanoMatrix surfaces as scaffolds for mesenchymal stem cell culture and growth

    PubMed Central

    Bhardwaj, Garima; Webster, Thomas J

    2016-01-01

    Stem cells are being widely investigated for a wide variety of applications in tissue engineering due to their ability to differentiate into a number of cells such as neurons, osteoblasts, and fibroblasts. This ability of stem cells to differentiate into different types of cells is greatly based on mechanical and chemical cues received from their three-dimensional environments. All organs are formed by a number of cells linked together via an extracellular matrix (ECM). The ECM is a complex network of proteins and carbohydrates, which occupies intercellular spaces and regulates cellular activity by controlling cell adhesion, migration, proliferation, and differentiation. The ECM is composed of two main types of macromolecules, namely, polysaccharide glycosaminoglycans, which are covalently attached to proteins in the form of proteoglycans and fibrous proteins belonging to two functional groups, structural (collagen and elastin) and adhesive (fibronectin, laminin, vitronectin, etc). Tissue engineering is a multidisciplinary field that aims to develop biomimetic scaffolds that emulate properties of the ECM to help repair or regenerate diseased or damaged tissue. This study introduces one of these matrices, XanoMatrix, as an optimal scaffold for tissue engineering applications, in particular, for stem cell research, based on its composition, nanofibrous structure, and porosity. Results of this study suggest that XanoMatrix scaffolds are promising for stem cell tissue engineering applications and as improved cell culture inserts for studying stem cell functions (compared to traditional Corning and Falcon cell culture plates) and, thus, should be further studied. PMID:27354795

  20. Molecular imaging of rheumatoid arthritis: emerging markers, tools, and techniques

    PubMed Central

    2014-01-01

    Early diagnosis and effective monitoring of rheumatoid arthritis (RA) are important for a positive outcome. Instant treatment often results in faster reduction of inflammation and, as a consequence, less structural damage. Anatomical imaging techniques have been in use for a long time, facilitating diagnosis and monitoring of RA. However, mere imaging of anatomical structures provides little information on the processes preceding changes in synovial tissue, cartilage, and bone. Molecular imaging might facilitate more effective diagnosis and monitoring in addition to providing new information on the disease pathogenesis. A limiting factor in the development of new molecular imaging techniques is the availability of suitable probes. Here, we review which cells and molecules can be targeted in the RA joint and discuss the advances that have been made in imaging of arthritis with a focus on such molecular targets as folate receptor, F4/80, macrophage mannose receptor, E-selectin, intercellular adhesion molecule-1, phosphatidylserine, and matrix metalloproteinases. In addition, we discuss a new tool that is being introduced in the field, namely the use of nanobodies as tracers. Finally, we describe additional molecules displaying specific features in joint inflammation and propose these as potential new molecular imaging targets, more specifically receptor activator of nuclear factor κB and its ligand, chemokine receptors, vascular cell adhesion molecule-1, αVβ3 integrin, P2X7 receptor, suppression of tumorigenicity 2, dendritic cell-specific transmembrane protein, and osteoclast-stimulatory transmembrane protein. PMID:25099015

  1. Cellular Interaction of Integrin α3β1 with Laminin 5 Promotes Gap Junctional Communication

    PubMed Central

    Lampe, Paul D.; Nguyen, Beth P.; Gil, Susana; Usui, Marcia; Olerud, John; Takada, Yoshikazu; Carter, William G.

    1998-01-01

    Wounding of skin activates epidermal cell migration over exposed dermal collagen and fibronectin and over laminin 5 secreted into the provisional basement membrane. Gap junctional intercellular communication (GJIC) has been proposed to integrate the individual motile cells into a synchronized colony. We found that outgrowths of human keratinocytes in wounds or epibole cultures display parallel changes in the expression of laminin 5, integrin α3β1, E-cadherin, and the gap junctional protein connexin 43. Adhesion of keratinocytes on laminin 5, collagen, and fibronectin was found to differentially regulate GJIC. When keratinocytes were adhered on laminin 5, both structural (assembly of connexin 43 in gap junctions) and functional (dye transfer) assays showed a two- to threefold increase compared with collagen and five- to eightfold over fibronectin. Based on studies with immobilized integrin antibody and integrin-transfected Chinese hamster ovary cells, the interaction of integrin α3β1 with laminin 5 was sufficient to promote GJIC. Mapping of intermediate steps in the pathway linking α3β1–laminin 5 interactions to GJIC indicated that protein trafficking and Rho signaling were both required. We suggest that adhesion of epithelial cells to laminin 5 in the basement membrane via α3β1 promotes GJIC that integrates individual cells into synchronized epiboles. PMID:9852164

  2. Flunarizine suppresses endothelial Angiopoietin-2 in a calcium - dependent fashion in sepsis

    PubMed Central

    Retzlaff, Jennifer; Thamm, Kristina; Ghosh, Chandra C.; Ziegler, Wolfgang; Haller, Hermann; Parikh, Samir M.; David, Sascha

    2017-01-01

    Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to an infection leading to systemic inflammation and endothelial barrier breakdown. The vascular-destabilizing factor Angiopoietin-2 (Angpt-2) has been implicated in these processes in humans. Here we screened in an unbiased approach FDA-approved compounds with respect to Angpt-2 suppression in endothelial cells (ECs) in vitro. We identified Flunarizine – a well-known anti-migraine calcium channel (CC) blocker – being able to diminish intracellular Angpt-2 protein in a time- and dose-dependent fashion thereby indirectly reducing the released protein. Moreover, Flunarizine protected ECs from TNFα-induced increase in Angpt-2 transcription and vascular barrier breakdown. Mechanistically, we could exclude canonical Tie2 signalling being responsible but found that three structurally distinct T-type - but not L-type - CC blockers can suppress Angpt-2. Most importantly, experimental increase in intracellular calcium abolished Flunarizine’s effect. Flunarizine was also able to block the injurious increase of Angpt-2 in murine endotoxemia in vivo. This resulted in reduced pulmonary adhesion molecule expression (intercellular adhesion molecule-1) and tissue infiltration of inflammatory cells (Gr-1). Our finding could have therapeutic implications as side effects of Flunarizine are low and specific sepsis therapeutics that target the dysregulated host response are highly desirable. PMID:28276491

  3. Flunarizine suppresses endothelial Angiopoietin-2 in a calcium - dependent fashion in sepsis.

    PubMed

    Retzlaff, Jennifer; Thamm, Kristina; Ghosh, Chandra C; Ziegler, Wolfgang; Haller, Hermann; Parikh, Samir M; David, Sascha

    2017-03-09

    Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to an infection leading to systemic inflammation and endothelial barrier breakdown. The vascular-destabilizing factor Angiopoietin-2 (Angpt-2) has been implicated in these processes in humans. Here we screened in an unbiased approach FDA-approved compounds with respect to Angpt-2 suppression in endothelial cells (ECs) in vitro. We identified Flunarizine - a well-known anti-migraine calcium channel (CC) blocker - being able to diminish intracellular Angpt-2 protein in a time- and dose-dependent fashion thereby indirectly reducing the released protein. Moreover, Flunarizine protected ECs from TNFα-induced increase in Angpt-2 transcription and vascular barrier breakdown. Mechanistically, we could exclude canonical Tie2 signalling being responsible but found that three structurally distinct T-type - but not L-type - CC blockers can suppress Angpt-2. Most importantly, experimental increase in intracellular calcium abolished Flunarizine's effect. Flunarizine was also able to block the injurious increase of Angpt-2 in murine endotoxemia in vivo. This resulted in reduced pulmonary adhesion molecule expression (intercellular adhesion molecule-1) and tissue infiltration of inflammatory cells (Gr-1). Our finding could have therapeutic implications as side effects of Flunarizine are low and specific sepsis therapeutics that target the dysregulated host response are highly desirable.

  4. Levels of Soluble Adhesion Molecules PECAM-1 and P-Selectin are Decreased in Children with Autism Spectrum Disorder

    PubMed Central

    Onore, Charity E.; Nordahl, Christine Wu; Young, Gregory S.; Van de Water, Judy A.; Rogers, Sally J.; Ashwood, Paul

    2012-01-01

    Background Although the etiopathology of Autism Spectrum Disorder (ASD) is not clear there is increasing evidence that dysfunction in the immune system affects many children with ASD. Findings of immune dysfunction in ASD include increases in inflammatory cytokines, chemokines and microglial activity in brain tissue and CSF, as well as abnormal peripheral immune cell function. Methods Adhesion molecules, such as platelet endothelial adhesion molecule-1 (PECAM-1), intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1), P-Selectin, and L-Selectin, function to facilitate leukocyte transendothelial migration. We assessed concentrations of soluble adhesion molecules, sPECAM-1, sICAM-1, sVCAM-1, sP-Selectin, and sL-Selectin in the plasma of 49 participants with ASD, and 31 typically developing controls of the same age, all of whom were enrolled as part of the Autism Phenome Project (APP). Behavioral assessment, the levels of soluble adhesion molecules, head circumference and MRI measurements of brain volume were compared in the same subjects. Results Levels of sPECAM-1 and sP-Selectin were significantly reduced in the ASD group compared to typically developing controls (p < 0.02). Soluble PECAM-1 levels were negatively associated with repetitive behavior and abnormal brain growth in children with ASD (p=0.03). Conclusions As adhesion molecules modulate the permeability and signaling at the blood brain barrier as well as leukocyte infiltration into the CNS, current data suggests a role for these molecules in the complex pathophysiology of ASD. PMID:22717029

  5. Intercellular Diffusion of a Fluorescent Sucrose Analog via the Septal Junctions in a Filamentous Cyanobacterium

    PubMed Central

    Nürnberg, Dennis J.; Mariscal, Vicente; Bornikoel, Jan; Nieves-Morión, Mercedes; Krauß, Norbert; Herrero, Antonia

    2015-01-01

    ABSTRACT Many filamentous cyanobacteria produce specialized nitrogen-fixing cells called heterocysts, which are located at semiregular intervals along the filament with about 10 to 20 photosynthetic vegetative cells in between. Nitrogen fixation in these complex multicellular bacteria depends on metabolite exchange between the two cell types, with the heterocysts supplying combined-nitrogen compounds but dependent on the vegetative cells for photosynthetically produced carbon compounds. Here, we used a fluorescent tracer to probe intercellular metabolite exchange in the filamentous heterocyst-forming cyanobacterium Anabaena sp. strain PCC 7120. We show that esculin, a fluorescent sucrose analog, is incorporated by a sucrose import system into the cytoplasm of Anabaena cells. The cytoplasmic esculin is rapidly and reversibly exchanged across vegetative-vegetative and vegetative-heterocyst cell junctions. Our measurements reveal the kinetics of esculin exchange and also show that intercellular metabolic communication is lost in a significant fraction of older heterocysts. SepJ, FraC, and FraD are proteins located at the intercellular septa and are suggested to form structures analogous to gap junctions. We show that a ΔsepJ ΔfraC ΔfraD triple mutant shows an altered septum structure with thinner septa but a denser peptidoglycan layer. Intercellular diffusion of esculin and fluorescein derivatives is impaired in this mutant, which also shows a greatly reduced frequency of nanopores in the intercellular septal cross walls. These findings suggest that FraC, FraD, and SepJ are important for the formation of junctional structures that constitute the major pathway for feeding heterocysts with sucrose. PMID:25784700

  6. Melanoma upregulates ICAM-1 expression on endothelial cells through engagement of tumor CD44 with endothelial E-selectin and activation of a PKCα–p38–SP-1 pathway

    PubMed Central

    Zhang, Pu; Goodrich, Chris; Fu, Changliang; Dong, Cheng

    2014-01-01

    Cancer metastasis involves multistep adhesive interactions between tumor cells (TCs) and endothelial cells (ECs), but the molecular mechanisms of intercellular communication in the tumor microenvironment remain elusive. Using static and flow coculture systems in conjunction with flow cytometry, we discovered that certain receptors on the ECs are upregulated on melanoma cell adhesion. Direct contact but not separate coculture between human umbilical endothelial cells (HUVECs) and a human melanoma cell line (Lu1205) increased intercellular adhesion molecule 1 (ICAM-1) and E-selectin expression on HUVECs by 3- and 1.5-fold, respectively, compared with HUVECs alone. The nonmetastatic cell line WM35 failed to promote ICAM-1 expression changes in HUVECs on contact. Enzyme-linked immunosorbent assay (ELISA) revealed that EC–TC contact has a synergistic effect on the expression of the cytokines interleukin (IL)-8, IL-6, and growth-related oncogene α (Gro-α). By using E-selectin cross-linking and beads coated with CD44 immunopurified from Lu1205 cells, we showed that CD44/selectin ligation was responsible for the ICAM-1 up-regulation on HUVECs. Protein kinase Cα (PKC-α) activation was found to be the downstream target of the CD44/selectin-initiated signaling, as ICAM-1 elevation was inhibited by siRNA targeting PKCα or a dominant negative form of PKCα (PKCα DN). Western blot analysis and electrophoretic mobility shift assays (EMSAs) showed that TC–EC contact mediated p38 phosphorylation and binding of the transcription factor SP-1 to its regulation site. In conclusion, CD44/selectin binding signals ICAM-1 up-regulation on the EC surface through a PKCα–p38–SP-1 pathway, which further enhances melanoma cell adhesion to ECs during metastasis.—Zhang, P., Goodrich, C., Fu, C., Dong, C. Melanoma upregulates ICAM-1 expression on ECs through engagement of tumor CD44 with endothelial E-selectin and activation of a PKCα–p38–SP-1 pathway. PMID:25138157

  7. Tumor necrosis factor -α, interleukin-10, intercellular and vascular adhesion molecules are possible biomarkers of disease severity in complicated Plasmodium vivax isolates from Pakistan.

    PubMed

    Raza, Afsheen; Ghanchi, Najia K; Sarwar Zubairi, Ali bin; Raheem, Ahmed; Nizami, Sobia; Beg, Mohammad Asim

    2013-01-01

    Cytokine-mediated endothelial activation pathway is a known mechanism of pathogenesis employed by Plasmodium falciparum to induce severe disease symptoms in human host. Though considered benign, complicated cases of Plasmodium vivax are being reported worldwide and from Pakistan. It has been hypothesized that P.vivax utilizes similar mechanism of pathogenesis, as that of P.falciparum for manifestations of severe malaria. Therefore, the main objective of this study was to characterize the role of cytokines and endothelial activation markers in complicated Plasmodium vivax isolates from Pakistan. A case control study using plasma samples from well-characterized groups suffering from P.vivax infection including uncomplicated cases (n=100), complicated cases (n=82) and healthy controls (n=100) were investigated. Base line levels of Tumor necrosis factor-α (TNF-α), Interleukin-6 (IL-6), Interleukin-10 (IL-10), Intercellular adhesion molecule-1 (ICAM-1), Vascular adhesion molecule-1(VCAM-1) and E-selectin were measured by ELISA. Correlation of cytokines and endothelial activation markers was done using Spearman's correlation analysis. Furthermore, significance of these biomarkers as indicators of disease severity was also analyzed. The results showed that TNF-α, IL-10, ICAM-1and VCAM-1 were 3-fold, 3.7 fold and 2 fold increased between uncomplicated and complicated cases. Comparison of healthy controls with uncomplicated cases showed no significant difference in TNF-α concentrations while IL-6, IL-10, ICAM-1, VCAM-1 and E-selectin were found to be elevated respectively. In addition, significant positive correlation was observed between TNF-α and IL-10/ ICAM-1, IL-6 and IL-10, ICAM-1 and VCAM-1.A Receiver operating curve (ROC) was generated which showed that TNF-α, IL-10, ICAM-1 and VCAM-1 were the best individual predictors of complicated P.vivax malaria. The results suggest that though endothelial adhesion molecules are inducible by pro-inflammatory cytokine TNF-α, however, cytokine-mediated endothelial activation pathway is not clearly demonstrated as a mechanism of pathogenesis in complicated P.vivax malaria cases from Pakistan.

  8. Sarcoptes scabiei (Acari: Sarcoptidae) Mite Extract Modulates Expression of Cytokines and Adhesion Molecules by Human Dermal Microvascular Endothelial Cells.

    PubMed Central

    Elder, B. Laurel; Arlian, Larry G.; Morgan, Marjorie S.

    2007-01-01

    The inflammatory and immune responses seen with the worldwide disease scabies (caused by the mite Sarcoptes scabiei) are complex. Clinical symptoms are delayed for weeks in patients when they are infested with scabies for the first time. This study was undertaken to elucidate the role of the human dermal microvascular endothelial cell (HMVEC-D) in modulating the inflammatory and immune responses in the skin to S. scabiei. Extracts of S. scabiei were incubated with HMVEC-D and the expression of adhesion molecules and chemokine receptors on the cells and the secretion of selected cytokines were determined by ELISA. S. scabiei extract was found to inhibit HMVEC-D expression of E-selectin and vascular cell adhesion molecule-1 (VCAM-1) although not intercellular adhesion molecule-1 (ICAM-1). The secretion of interleukin-8 (IL-8) was also inhibited by S. scabiei extract. S. scabiei extract increased expression of the chemokine receptor CXCR-1, and both down-regulated and up-regulated expression of CXCR-2 depending on the concentration tested. These findings help explain the delayed inflammatory reaction to infestation with S. scabiei. PMID:17017228

  9. Reevaluating αE-catenin monomer and homodimer functions by characterizing E-cadherin/αE-catenin chimeras

    PubMed Central

    Bianchini, Julie M.; Kitt, Khameeka N.; Gloerich, Martijn; Pokutta, Sabine; Weis, William I.

    2015-01-01

    As part of the E-cadherin–β-catenin–αE-catenin complex (CCC), mammalian αE-catenin binds F-actin weakly in the absence of force, whereas cytosolic αE-catenin forms a homodimer that interacts more strongly with F-actin. It has been concluded that cytosolic αE-catenin homodimer is not important for intercellular adhesion because E-cadherin/αE-catenin chimeras thought to mimic the CCC are sufficient to induce cell–cell adhesion. We show that, unlike αE-catenin in the CCC, these chimeras homodimerize, bind F-actin strongly, and inhibit the Arp2/3 complex, all of which are properties of the αE-catenin homodimer. To more accurately mimic the junctional CCC, we designed a constitutively monomeric chimera, and show that E-cadherin–dependent cell adhesion is weaker in cells expressing this chimera compared with cells in which αE-catenin homodimers are present. Our results demonstrate that E-cadherin/αE-catenin chimeras used previously do not mimic αE-catenin in the native CCC, and imply that both CCC-bound monomer and cytosolic homodimer αE-catenin are required for strong cell–cell adhesion. PMID:26416960

  10. Pirfenidone induces intercellular adhesion molecule-1 (ICAM-1) down-regulation on cultured human synovial fibroblasts

    PubMed Central

    Kaneko, M; Inoue, H; Nakazawa, R; Azuma, N; Suzuki, M; Yamauchi, S; Margolin, S B; Tsubota, K; Saito, I

    1998-01-01

    Pirfenidone has been shown to modify some cytokine regulatory actions and inhibit fibroblast biochemical reactions resulting in inhibition of proliferation and collagen matrix synthesis by fibroblast. We have investigated the effect of pirfenidone on the expression of cell adhesion molecules. The synovial fibroblasts were treated with IL-1α in the presence or absence of pirfenidone (range 0–1000 μm), and assayed for the expression of adhesion molecules such as ICAM-1 and endothelial-leucocyte adhesion molecule-1 (E-selectin) by cell ELISA. Pirfenidone significantly down-regulated the expression of ICAM-1 on cultured synovial fibroblasts in a dose-dependent manner. In contrast, expression of E-selectin was not affected. Furthermore, we examined whether pirfenidone affects the cellular binding between cultured lymphocytes and IL-1α-stimulated synovial fibroblasts by in vitro binding assay and found their mutual binding was significantly suppressed in a dose-dependent manner by pirfenidone. It is speculated that down-regulation of ICAM-1 might be one of the novel mechanisms of action of pirfenidone. These data indicate a novel mechanism of action for pirfenidone to reduce the activation of synovial fibroblasts. PMID:9697986

  11. Mesalamine modulates intercellular adhesion through inhibition of p-21 activated kinase-1

    PubMed Central

    Khare, Vineeta; Lyakhovich, Alex; Dammann, Kyle; Lang, Michaela; Borgmann, Melanie; Tichy, Boris; Pospisilova, Sarka; Luciani, Gloria; Campregher, Christoph; Evstatiev, Rayko; Pflueger, Maren; Hundsberger, Harald; Gasche, Christoph

    2013-01-01

    Mesalamine (5-ASA) is widely used for the treatment of ulcerative colitis, a remitting condition characterized by chronic inflammation of the colon. Knowledge about the molecular and cellular targets of 5-ASA is limited and a clear understanding of its activity in intestinal homeostasis and interference with neoplastic progression is lacking. We sought to identify molecular pathways interfered by 5-ASA, using CRC cell lines with different genetic background. Microarray was performed for gene expression profile of 5-ASA-treated and untreated cells (HCT116 and HT29). Filtering and analysis of data identified three oncogenic pathways interfered by 5-ASA: MAPK/ERK pathway, cell adhesion and β-catenin/Wnt signaling. PAK1 emerged as a consensus target of 5-ASA, orchestrating these pathways. We further investigated the effect of 5-ASA on cell adhesion. 5-ASA increased cell adhesion which was measured by cell adhesion assay and transcellular-resistance measurement. Moreover, 5-ASA treatment restored membranous expression of adhesion molecules E-cadherin and β-catenin. Role of PAK1 as a mediator of mesalamine activity was validated in vitro and in vivo. Inhibition of PAK1 by RNA interference also increased cell adhesion. PAK1 expression was elevated in APCmin polyps and 5-ASA treatment reduced its expression. Our data demonstrates novel pharmacological mechanism of mesalamine in modulation of cell adhesion and role of PAK1 in APCmin polyposis. We propose that inhibition of PAK1 expression by 5-ASA can impede with neoplastic progression in colorectal carcinogenesis. The mechanism of PAK1 inhibition and induction of membranous translocation of adhesion proteins by 5-ASA might be independent of its known anti-inflammatory action. PMID:23146664

  12. Mesalamine modulates intercellular adhesion through inhibition of p-21 activated kinase-1.

    PubMed

    Khare, Vineeta; Lyakhovich, Alex; Dammann, Kyle; Lang, Michaela; Borgmann, Melanie; Tichy, Boris; Pospisilova, Sarka; Luciani, Gloria; Campregher, Christoph; Evstatiev, Rayko; Pflueger, Maren; Hundsberger, Harald; Gasche, Christoph

    2013-01-15

    Mesalamine (5-ASA) is widely used for the treatment of ulcerative colitis, a remitting condition characterized by chronic inflammation of the colon. Knowledge about the molecular and cellular targets of 5-ASA is limited and a clear understanding of its activity in intestinal homeostasis and interference with neoplastic progression is lacking. We sought to identify molecular pathways interfered by 5-ASA, using CRC cell lines with different genetic background. Microarray was performed for gene expression profile of 5-ASA-treated and untreated cells (HCT116 and HT29). Filtering and analysis of data identified three oncogenic pathways interfered by 5-ASA: MAPK/ERK pathway, cell adhesion and β-catenin/Wnt signaling. PAK1 emerged as a consensus target of 5-ASA, orchestrating these pathways. We further investigated the effect of 5-ASA on cell adhesion. 5-ASA increased cell adhesion which was measured by cell adhesion assay and transcellular-resistance measurement. Moreover, 5-ASA treatment restored membranous expression of adhesion molecules E-cadherin and β-catenin. Role of PAK1 as a mediator of mesalamine activity was validated in vitro and in vivo. Inhibition of PAK1 by RNA interference also increased cell adhesion. PAK1 expression was elevated in APC(min) polyps and 5-ASA treatment reduced its expression. Our data demonstrates novel pharmacological mechanism of mesalamine in modulation of cell adhesion and role of PAK1 in APC(min) polyposis. We propose that inhibition of PAK1 expression by 5-ASA can impede with neoplastic progression in colorectal carcinogenesis. The mechanism of PAK1 inhibition and induction of membranous translocation of adhesion proteins by 5-ASA might be independent of its known anti-inflammatory action. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Tumor necrosis factor alpha (TNF-alpha)-induced cell adhesion to human endothelial cells is under dominant control of one TNF receptor type, TNF-R55

    PubMed Central

    1993-01-01

    Tumor necrosis factor alpha (TNF-alpha) is a pleiotropic cytokine triggering cell responses through two distinct membrane receptors. Stimulation of leukocyte adhesion to the endothelium is one of the many TNF-alpha activities and is explained by the upregulation of adhesion molecules on the endothelial cell surface. Human umbilical vein endothelial cells (HUVEC) were isolated, cultured, and demonstrated to express both TNF receptor types, TNF-R55 and TNF-R75. Cell adhesion to HUVEC was studied using the HL60, U937, and MOLT-4 cell lines. HUVEC were activated by either TNF-alpha, binding to both TNF-R55 and TNF- R75, and by receptor type-specific agonists, binding exclusively to TNF- R55 or to TNF-R75. The TNF-alpha-induced cell adhesion to HUVEC was found to be controlled almost exclusively by TNF-R55. This finding correlated with the exclusive activity of TNF-R55 in the TNF-alpha- dependent regulation of the expression of the intercellular adhesion molecule type 1 (ICAM-1), E-selectin, and vascular cell adhesion molecule type 1 (VCAM-1). The CD44 adhesion molecule in HUVEC was also found to be upregulated through TNF-R55. However, both TNF-R55 and TNF- R75 upregulate alpha 2 integrin expression in HUVEC. The predominant role of TNF-R55 in TNF-alpha-induced adhesion in HUVEC may correlate with its specific control of NF-kappa B activation, since kappa B elements are known to be present in ICAM-1, E-selectin, and VCAM-1 gene regulatory sequences. PMID:8386742

  14. HIV-1 gp120 Glycoprotein Interacting with Dendritic Cell-specific Intercellular Adhesion Molecule 3-grabbing Non-integrin (DC-SIGN) Down-Regulates Tight Junction Proteins to Disrupt the Blood Retinal Barrier and Increase Its Permeability.

    PubMed

    Qian, Yi-Wen; Li, Chuan; Jiang, Ai-Ping; Ge, Shengfang; Gu, Ping; Fan, Xianqun; Li, Tai-Sheng; Jin, Xia; Wang, Jian-Hua; Wang, Zhi-Liang

    2016-10-28

    Approximately 70% of HIV-1 infected patients acquire ocular opportunistic infections and manifest eye disorders during the course of their illness. The mechanisms by which pathogens invade the ocular site, however, are unclear. Under normal circumstances, vascular endothelium and retinal pigment epithelium (RPE), which possess a well developed tight junction complex, form the blood-retinal barrier (BRB) to prevent pathogen invasion. We hypothesize that disruption of the BRB allows pathogen entry into ocular sites. The hypothesis was tested using in vitro models. We discovered that human RPE cells could bind to either HIV-1 gp120 glycoproteins or HIV-1 viral particles. Furthermore, the binding was mediated by dendritic cell-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN) expressed on RPE cells. Upon gp120 binding to DC-SIGN, cellular NF-κB signaling was triggered, leading to the induction of matrix metalloproteinases, which subsequently degraded tight junction proteins and disrupted the BRB integrity. DC-SIGN knockdown or prior blocking with a specific antibody abolished gp120-induced matrix metalloproteinase expression and reduced the degradation of tight junction proteins. This study elucidates a novel mechanism by which HIV, type 1 invades ocular tissues and provides additional insights into the translocation or invasion process of ocular complication-associated pathogens. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  15. Cafestol Inhibits Cyclic-Strain-Induced Interleukin-8, Intercellular Adhesion Molecule-1, and Monocyte Chemoattractant Protein-1 Production in Vascular Endothelial Cells

    PubMed Central

    Hao, Wen-Rui; Sung, Li-Chin; Chen, Chun-Chao; Chen, Jin-Jer

    2018-01-01

    Moderate coffee consumption is inversely associated with cardiovascular disease mortality; however, mechanisms underlying this causal effect remain unclear. Cafestol, a diterpene found in coffee, has various properties, including an anti-inflammatory property. This study investigated the effect of cafestol on cyclic-strain-induced inflammatory molecule secretion in vascular endothelial cells. Cells were cultured under static or cyclic strain conditions, and the secretion of inflammatory molecules was determined using enzyme-linked immunosorbent assay. The effects of cafestol on mitogen-activated protein kinases (MAPK), heme oxygenase-1 (HO-1), and sirtuin 1 (Sirt1) signaling pathways were examined using Western blotting and specific inhibitors. Cafestol attenuated cyclic-strain-stimulated intercellular adhesion molecule-1 (ICAM-1), monocyte chemoattractant protein- (MCP-) 1, and interleukin- (IL-) 8 secretion. Cafestol inhibited the cyclic-strain-induced phosphorylation of extracellular signal-regulated kinase and p38 MAPK. By contrast, cafestol upregulated cyclic-strain-induced HO-1 and Sirt1 expression. The addition of zinc protoporphyrin IX, sirtinol, or Sirt1 silencing (transfected with Sirt1 siRNA) significantly attenuated cafestol-mediated modulatory effects on cyclic-strain-stimulated ICAM-1, MCP-1, and IL-8 secretion. This is the first study to report that cafestol inhibited cyclic-strain-induced inflammatory molecule secretion, possibly through the activation of HO-1 and Sirt1 in endothelial cells. The results provide valuable insights into molecular pathways that may contribute to the effects of cafestol. PMID:29854096

  16. Comparative Expression of CD34, Intercellular Adhesion Molecule-1, and Podoplanin and the Presence of Mast Cells in Periapical Granulomas, Cysts, and Residual Cysts.

    PubMed

    Lopes, Cristiane Barbosa; Armada, Luciana; Pires, Fábio Ramôa

    2018-07-01

    The aim of the present study was to compare the immunoexpression of CD34, intercellular adhesion molecule-1 (ICAM-1), and podoplanin and the presence of mast cells with clinical, demographic, radiologic, and histologic features from periapical granulomas, periapical cysts, and residual cysts. Thirty-one lesions (5 granulomas, 15 periapical cysts, and 11 residual cysts) were selected. Histologic sections in silanized slides were used for the immunohistochemical reactions. The analysis of the images was performed by using an optical microscope, and data were analyzed with 5% significance (P < .05). Cysts presented atrophic and hyperplastic epithelium in 11 cases (35.5%) and 15 cases (48.8%), respectively (P > .05). The intensity of the inflammatory infiltrate was similar when comparing the 3 groups (P > .05). CD34 and podoplanin expression and the presence of mast cells were similar when comparing the 3 groups; ICAM-1 expression was more intense in granulomas than cysts (P < .05). There were no statistically significant differences associated with the expression of the evaluated markers according to the intensity of the inflammatory infiltrate. There were no differences in the expression of CD34 and podoplanin and in the presence of mast cells when the 3 groups were compared. ICAM-1 expression was more common in periapical granulomas. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  17. Metazoans evolved by taking domains from soluble proteins to expand intercellular communication network

    PubMed Central

    Nam, Hyun-Jun; Kim, Inhae; Bowie, James U.; Kim, Sanguk

    2015-01-01

    A central question in animal evolution is how multicellular animals evolved from unicellular ancestors. We hypothesize that membrane proteins must be key players in the development of multicellularity because they are well positioned to form the cell-cell contacts and to provide the intercellular communication required for the creation of complex organisms. Here we find that a major mechanism for the necessary increase in membrane protein complexity in the transition from non-metazoan to metazoan life was the new incorporation of domains from soluble proteins. The membrane proteins that have incorporated soluble domains in metazoans are enriched in many of the functions unique to multicellular organisms such as cell-cell adhesion, signaling, immune defense and developmental processes. They also show enhanced protein-protein interaction (PPI) network complexity and centrality, suggesting an important role in the cellular diversification found in complex organisms. Our results expose an evolutionary mechanism that contributed to the development of higher life forms. PMID:25923201

  18. Short communication: Effects of lactose and milk on the expression of biofilm-associated genes in Staphylococcus aureus strains isolated from a dairy cow with mastitis.

    PubMed

    Xue, Ting; Chen, Xiaolin; Shang, Fei

    2014-10-01

    Staphylococcus aureus is the main etiological organism responsible for bovine mastitis. The ability of S. aureus to form biofilms plays an important role in the pathogenesis of mastitis. Biofilm formation in S. aureus is associated with the production of polysaccharide intercellular adhesin (PIA) protein and several other proteins. Several environmental factors, including glucose, osmolarity, oleic acid, temperature, and anaerobiosis, have been reported to affect biofilm formation in S. aureus. This study investigated the influence of lactose and milk on the biofilm formation capacity of 2 clinical bovine isolates of S. aureus. We found that lactose increased biofilm formation predominantly by inducing PIA production, whereas milk increased biofilm formation through PIA as well as by increasing the production of other biofilm-associated proteins, which might be mediated by the transcriptional regulators intercellular adhesion regulator (icaR) and repressor of biofilm (rbf). Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  19. Sal-like 4 (SALL4) suppresses CDH1 expression and maintains cell dispersion in basal-like breast cancer.

    PubMed

    Itou, Junji; Matsumoto, Yoshiaki; Yoshikawa, Kiyotsugu; Toi, Masakazu

    2013-09-17

    In cell cultures, the dispersed phenotype is indicative of the migratory ability. Here we characterized Sal-like 4 (SALL4) as a dispersion factor in basal-like breast cancer. Our shRNA-mediated SALL4 knockdown system and SALL4 overexpression system revealed that SALL4 suppresses the expression of adhesion gene CDH1, and positively regulates the CDH1 suppressor ZEB1. Cell behavior analyses showed that SALL4 suppresses intercellular adhesion and maintains cell motility after cell-cell interaction and cell division, which results in the dispersed phenotype. Our findings indicate that SALL4 functions to suppress CDH1 expression and to maintain cell dispersion in basal-like breast cancer. Copyright © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  20. E-Cadherin-Dependent Stimulation of Traction Force at Focal Adhesions via the Src and PI3K Signaling Pathways

    PubMed Central

    Jasaitis, Audrius; Estevez, Maruxa; Heysch, Julie; Ladoux, Benoit; Dufour, Sylvie

    2012-01-01

    The interplay between cadherin- and integrin-dependent signals controls cell behavior, but the precise mechanisms that regulate the strength of adhesion to the extracellular matrix remains poorly understood. We deposited cells expressing a defined repertoire of cadherins and integrins on fibronectin (FN)-coated polyacrylamide gels (FN-PAG) and on FN-coated pillars used as a micro-force sensor array (μFSA), and analyzed the functional relationship between these adhesion receptors to determine how it regulates cell traction force. We found that cadherin-mediated adhesion stimulated cell spreading on FN-PAG, and this was modulated by the substrate stiffness. We compared S180 cells with cells stably expressing different cadherins on μFSA and found that traction forces were stronger in cells expressing cadherins than in parental cells. E-cadherin-mediated contact and mechanical coupling between cells are required for this increase in cell-FN traction force, which was not observed in isolated cells, and required Src and PI3K activities. Traction forces were stronger in cells expressing type I cadherins than in cells expressing type II cadherins, which correlates with our previous observation of a higher intercellular adhesion strength developed by type I compared with type II cadherins. Our results reveal one of the mechanisms whereby molecular cross talk between cadherins and integrins upregulates traction forces at cell-FN adhesion sites, and thus provide additional insight into the molecular control of cell behavior. PMID:22853894

  1. The RhoA/ROCK Pathway Ameliorates Adhesion and Inflammatory Infiltration Induced by AGEs in Glomerular Endothelial Cells.

    PubMed

    Rao, Jialing; Ye, Zengchun; Tang, Hua; Wang, Cheng; Peng, Hui; Lai, Weiyan; Li, Yin; Huang, Wanbing; Lou, Tanqi

    2017-01-05

    A recent study demonstrated that advanced glycation end products (AGEs) play a role in monocyte infiltration in mesangial areas in diabetic nephropathy. The Ras homolog gene family, member A Rho kinase (RhoA/ROCK) pathway plays a role in regulating cell migration. We hypothesized that the RhoA/ROCK pathway affects adhesion and inflammation in endothelial cells induced by AGEs. Rat glomerular endothelial cells (rGECs) were cultured with AGEs (80 μg/ml) in vitro. The ROCK inhibitor Y27632 (10 nmol/l) and ROCK1-siRNA were used to inhibit ROCK. We investigated levels of the intercellular adhesion molecule 1 (ICAM-1) and monocyte chemoattractant protein1 (MCP-1) in rGECs. Db/db mice were used as a diabetes model and received Fasudil (10 mg/kg/d, n = 6) via intraperitoneal injection for 12 weeks. We found that AGEs increased the expression of ICAM-1 and MCP-1 in rGECs, and the RhoA/ROCK pathway inhibitor Y27632 depressed the release of adhesion molecules. Moreover, blocking the RhoA/ROCK pathway ameliorated macrophage transfer to the endothelium. Reduced expression of adhesion molecules and amelioration of inflammatory cell infiltration in the glomerulus were observed in db/db mice treated with Fasudil. The RhoA/ROCK pathway plays a role in adhesion molecule expression and inflammatory cell infiltration in glomerular endothelial cells induced by AGEs.

  2. Signal Regulatory Protein α Negatively Regulates β2 Integrin-Mediated Monocyte Adhesion, Transendothelial Migration and Phagocytosis

    PubMed Central

    Liu, Dan-Qing; Li, Li-Min; Guo, Ya-Lan; Bai, Rui; Wang, Chen; Bian, Zhen; Zhang, Chen-Yu; Zen, Ke

    2008-01-01

    Background Signal regulate protein α (SIRPα) is involved in many functional aspects of monocytes. Here we investigate the role of SIRPα in regulating β2 integrin-mediated monocyte adhesion, transendothelial migration (TEM) and phagocytosis. Methodology/Principal Findings THP-1 monocytes/macropahges treated with advanced glycation end products (AGEs) resulted in a decrease of SIRPα expression but an increase of β2 integrin cell surface expression and β2 integrin-mediated adhesion to tumor necrosis factor-α (TNFα)–stimulated human microvascular endothelial cell (HMEC-1) monolayers. In contrast, SIRPα overexpression in THP-1 cells showed a significant less monocyte chemotactic protein-1 (MCP-1)–triggered cell surface expression of β2 integrins, in particular CD11b/CD18. SIRPα overexpression reduced β2 integrin-mediated firm adhesion of THP-1 cells to either TNFα–stimulated HMEC-1 monolayers or to immobilized intercellular adhesion molecule-1 (ICAM-1). SIRPα overexpression also reduced MCP-1–initiated migration of THP-1 cells across TNFα–stimulated HMEC-1 monolayers. Furthermore, β2 integrin-mediated THP-1 cell spreading and actin polymerization in response to MCP-1, and phagocytosis of bacteria were both inhibited by SIRPα overexpression. Conclusions/Significance SIRPα negatively regulates β2 integrin-mediated monocyte adhesion, transendothelial migration and phagocytosis, thus may serve as a critical molecule in preventing excessive activation and accumulation of monocytes in the arterial wall during early stage of atherosclerosis. PMID:18820737

  3. In vitro effects of ATG-Fresenius on immune cell adhesion.

    PubMed

    Kanzler, I; Seitz-Merwald, I; Schleger, S; Kaczmarek, I; Kur, F; Beiras-Fernandez, A

    2013-06-01

    ATG-Fresenius, a purified rabbit polyclonal anti-human T-lymphocyte immunoglobulin is used for induction immunosuppression as well as prevention and treatment of acute rejection episodes among patients receiving solid organ transplants. The aim of this study was to investigate the in vitro activity of ATG-Fresenius upon immune cell adhesion, which may explain its activity to mitigate ischemia-reperfusion injury. Human vascular endothelial cells (HUVEC) and peripheral blood mononuclear cells (PBMCs) isolated from umbilical vein or peripheral blood were incubated 20 to 24 hours before analysis. HUVEC were incubated with 10 and 100 μg/mL ATG-Fresenius or reference polyclonal rabbit immunoglobulin G. Analysis of immune cell adhesion to endothelial cells was studied in cocultures of PBMCs and adherent HUVEC. Endothelial cell expression of adhesion molecules CD62E and CD54 was determined by flow cytometry. The numbers of T-, B- and natural killer cells attached to HUVEC were also determined by flow cytometry. Groups were compared using one-way analysis of variance. We showed that ATG-Fresenius binds to endothelial cells particularly activated ones expressing increased levels of E-selectin and ICAM-1. The increased binding of ATG-Fresenius to activated endothelial cells was consistent with its known binding to Intercellular Adhesion Molecule 1 (ICAM-1) and selectins. We also showed that ATG-Fresenius inhibited adhesion of prestimulated immune cells to activated endothelium. We demonstrated dose-dependent binding of ATG-Fresenius to activated endothelial cells. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Tumor necrosis factor α (TNF-α) receptor-II is required for TNF-α–induced leukocyte-endothelial interaction in vivo

    PubMed Central

    Chandrasekharan, Unni M.; Siemionow, Maria; Unsal, Murat; Yang, Lin; Poptic, Earl; Bohn, Justin; Ozer, Kagan; Zhou, Zhongmin; Howe, Philip H.; Penn, Marc

    2007-01-01

    Tumor necrosis factor-α (TNF-α) binds to 2 distinct cell-surface receptors: TNF-α receptor-I (TNFR-I: p55) and TNF-α receptor-II (TNFR-II: p75). TNF-α induces leukocyte adhesion molecules on endothelial cells (ECs), which mediate 3 defined steps of the inflammatory response; namely, leukocyte rolling, firm adhesion, and transmigration. In this study, we have investigated the role of p75 in TNF-α–induced leukocyte adhesion molecules using cultured ECs derived from wild-type (WT), p75-null (p75−/−), or p55-null (p55−/−) mice. We observed that p75 was essential for TNF-α–induced E-selectin, vascular cell adhesion molecule 1 (VCAM-1), and intercellular adhesion molecule 1 (ICAM-1) expression. We also investigated the putative role of p75 in inflammation in vivo using an intravital microscopic approach with a mouse cremaster muscle model. TNF-α–stimulated leukocyte rolling, firm adhesion to ECs, and transmigration were dramatically reduced in p75−/− mice. Transplanted WT cremaster in p75−/− mice showed a robust leukocyte rolling and firm adhesion upon TNF-α activation, suggesting that the impairment in EC-leukocyte interaction in p75−/− mice is due to EC dysfunction. These results demonstrate, for the first time, that endothelial p75 is essential for TNF-α–induced leukocyte–endothelial-cell interaction. Our findings may contribute to the identification of novel p75-targeted therapeutic approaches for inflammatory diseases. PMID:17068152

  5. Streptococcus pyogenes Phospholipase A2 Induces the Expression of Adhesion Molecules on Human Umbilical Vein Endothelial Cells and Aorta of Mice.

    PubMed

    Oda, Masataka; Domon, Hisanori; Kurosawa, Mie; Isono, Toshihito; Maekawa, Tomoki; Yamaguchi, Masaya; Kawabata, Shigetada; Terao, Yutaka

    2017-01-01

    The Streptococcus pyogenes phospholipase A 2 (SlaA) gene is highly conserved in the M3 serotype of group A S. pyogenes , which often involves hypervirulent clones. However, the role of SlaA in S. pyogenes pathogenesis is unclear. Herein, we report that SlaA induces the expression of intercellular adhesion molecule 1 (ICAM1) and vascular cell adhesion molecule 1 (VCAM1) via the arachidonic acid signaling cascade. Notably, recombinant SlaA induced ICAM1 and VCAM1 expression in human umbilical vein endothelial cells (HUVECs), resulting in enhanced adhesion of human monocytic leukemia (THP-1) cells. However, C134A, a variant enzyme with no enzymatic activity, did not induce such events. In addition, culture supernatants from S. pyogenes SSI-1 enhanced the adhesion of THP-1 cells to HUVECs, but culture supernatants from the Δ slaA isogenic mutant strain had limited effects. Aspirin, a cyclooxygenase 2 inhibitor, prevented the adhesion of THP-1 cells to HUVECs and did not induce ICAM1 and VCAM1 expression in HUVECs treated with SlaA. However, zileuton, a 5-lipoxygenase inhibitor, did not exhibit such effects. Furthermore, pre-administration of aspirin in mice intravenously injected with SlaA attenuated the transcriptional abundance of ICAM1 and VCAM1 in the aorta. These results suggested that SlaA from S. pyogenes stimulates the expression of adhesion molecules in vascular endothelial cells. Thus, SlaA contributes to the inflammation of vascular endothelial cells upon S. pyogenes infection.

  6. Peptides based on alphaV-binding domains of erythrocyte ICAM-4 inhibit sickle red cell-endothelial interactions and vaso-occlusion in the microcirculation.

    PubMed

    Kaul, Dhananjay K; Liu, Xiao-du; Zhang, Xiaoqin; Mankelow, Tosti; Parsons, Stephen; Spring, Frances; An, Xiuli; Mohandas, Narla; Anstee, David; Chasis, Joel Anne

    2006-11-01

    Growing evidence shows that adhesion molecules on sickle erythrocytes interact with vascular endothelium leading to vaso-occlusion. Erythrocyte intercellular adhesion molecule-4 (ICAM-4) binds alphaV-integrins, including alphaVbeta3 on endothelial cells. To explore the contribution of ICAM-4 to vascular pathology of sickle cell disease, we tested the effects of synthetic peptides, V(16)PFWVRMS (FWV) and T(91)RWATSRI (ATSR), based on alphaV-binding domains of ICAM-4 and capable of inhibiting ICAM-4 and alphaV-binding in vitro. For these studies, we utilized an established ex vivo microvascular model system that enables intravital microscopy and quantitation of adhesion under shear flow. In this model, the use of platelet-activating factor, which causes endothelial oxidant generation and endothelial activation, mimicked physiological states known to occur in sickle cell disease. Infusion of sickle erythrocytes into platelet-activating factor-treated ex vivo rat mesocecum vasculature produced pronounced adhesion of erythrocytes; small-diameter venules were sites of maximal adhesion and frequent blockage. Both FWV and ATSR peptides markedly decreased adhesion, and no vessel blockage was observed with either of the peptides, resulting in improved hemodynamics. ATSR also inhibited adhesion in unactivated microvasculature. Although infused fluoresceinated ATSR colocalized with vascular endothelium, pretreatment with function-blocking antibody to alphaVbeta3-integrin markedly inhibited this interaction. Our data strengthen the thesis that ICAM-4 on sickle erythrocytes binds endothelium via alphaVbeta3 and that this interaction contributes to vaso-occlusion. Thus peptides or small molecule mimetics of ICAM-4 may have therapeutic potential.

  7. Cryptotanshinone inhibits oxidized LDL-induced adhesion molecule expression via ROS dependent NF-κB pathways

    PubMed Central

    Zhao, Wenwen; Wu, Chuanhong; Chen, Xiuping

    2016-01-01

    ABSTRACT Adhesion molecules, such as intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin, play important roles in the initial stage of atherosclerosis. Cryptotanshinone (CPT), a natural compound isolated from Salvia miltiorrhiza Bunge, exhibits anti-atherosclerotic activity although the underlying mechanisms remain elusive. In this study, the protective effect of CPT against oxidized low-density lipoprotein (ox-LDL)-induced adhesion molecule expression was investigated in human umbilical vein endothelial cells. Ox-LDL significantly induced ICAM-1, VCAM-1, and E-selectin expression at the mRNA and protein levels but reduced eNOS phosphorylation and NO generation, which were reversed by CPT pretreatment. Sodium nitroprusside, a NO donor, N-acetyl-L-cysteine (NAC), a reactive oxygen species (ROS) scavenger, and BAY117082, a NF-κB inhibitor, inhibited ox-LDL-induced ICAM-1, VCAM-1, and E-selectin expression. Ox-LDL-induced ROS production was significantly inhibited by CPT and NAC. Furthermore, ox-LDL activated the NF-κB signaling pathway by inducing phosphorylation of IKKβ and IκBα, promoting the interaction of IKKβ and IκBα, and increasing p65 nuclear translocation, which were significantly inhibited by CPT. In addition, CPT, NAC, and BAY117082 inhibited ox-LDL-induced membrane expression of ICAM-1, VCAM-1, E-selectin, and endothelial–monocyte adhesion and restored eNOS phosphorylation and NO generation. Results suggested that CPT inhibited ox-LDL-induced adhesion molecule expression by decreasing ROS and inhibiting the NF-κB pathways, which provides new insight into the anti-atherosclerotic mechanism of CPT. PMID:26647279

  8. Connexin-43 upregulation in micrometastases and tumor vasculature and its role in tumor cell attachment to pulmonary endothelium

    PubMed Central

    Elzarrad, M Khair; Haroon, Abu; Willecke, Klaus; Dobrowolski, Radoslaw; Gillespie, Mark N; Al-Mehdi, Abu-Bakr

    2008-01-01

    Background The modulation of gap junctional communication between tumor cells and between tumor and vascular endothelial cells during tumorigenesis and metastasis is complex. The notion of a role for loss of gap junctional intercellular communication in tumorigenesis and metastasis has been controversial. While some of the stages of tumorigenesis and metastasis, such as uncontrolled cell division and cellular detachment, would necessitate the loss of intercellular junctions, other stages, such as intravasation, endothelial attachment, and vascularization, likely require increased cell-cell contact. We hypothesized that, in this multi-stage scheme, connexin-43 is centrally involved as a cell adhesion molecule mediating metastatic tumor attachment to the pulmonary endothelium. Methods Tumor cell attachment to pulmonary vasculature, tumor growth, and connexin-43 expression was studied in metastatic lung tumor sections obtained after tail-vein injection into nude mice of syngeneic breast cancer cell lines, overexpressing wild type connexin-43 or dominant-negatively mutated connexin-43 proteins. High-resolution immunofluorescence microscopy and Western blot analysis was performed using a connexin-43 monoclonal antibody. Calcein Orange Red AM dye transfer by fluorescence imaging was used to evaluate the gap junction function. Results Adhesion of breast cancer cells to the pulmonary endothelium increased with cancer cells overexpressing connexin-43 and markedly decreased with cells expressing dominant-negative connexin-43. Upregulation of connexin-43 was observed in tumor cell-endothelial cell contact areas in vitro and in vivo, and in areas of intratumor blood vessels and in micrometastatic foci. Conclusion Connexin-43 facilitates metastatic 'homing' by increasing adhesion of cancer cells to the lung endothelial cells. The marked upregulation of connexin-43 in tumor cell-endothelial cell contact areas, whether in preexisting 'homing' vessels or in newly formed tumor vessels, suggests that connexin-43 can serve as a potential marker of micrometastases and tumor vasculature and that it may play a role in the early incorporation of endothelial cells into small tumors as seeds for vasculogenesis. PMID:18647409

  9. Connexin-43 upregulation in micrometastases and tumor vasculature and its role in tumor cell attachment to pulmonary endothelium.

    PubMed

    Elzarrad, M Khair; Haroon, Abu; Willecke, Klaus; Dobrowolski, Radoslaw; Gillespie, Mark N; Al-Mehdi, Abu-Bakr

    2008-07-22

    The modulation of gap junctional communication between tumor cells and between tumor and vascular endothelial cells during tumorigenesis and metastasis is complex. The notion of a role for loss of gap junctional intercellular communication in tumorigenesis and metastasis has been controversial. While some of the stages of tumorigenesis and metastasis, such as uncontrolled cell division and cellular detachment, would necessitate the loss of intercellular junctions, other stages, such as intravasation, endothelial attachment, and vascularization, likely require increased cell-cell contact. We hypothesized that, in this multi-stage scheme, connexin-43 is centrally involved as a cell adhesion molecule mediating metastatic tumor attachment to the pulmonary endothelium. Tumor cell attachment to pulmonary vasculature, tumor growth, and connexin-43 expression was studied in metastatic lung tumor sections obtained after tail-vein injection into nude mice of syngeneic breast cancer cell lines, overexpressing wild type connexin-43 or dominant-negatively mutated connexin-43 proteins. High-resolution immunofluorescence microscopy and Western blot analysis was performed using a connexin-43 monoclonal antibody. Calcein Orange Red AM dye transfer by fluorescence imaging was used to evaluate the gap junction function. Adhesion of breast cancer cells to the pulmonary endothelium increased with cancer cells overexpressing connexin-43 and markedly decreased with cells expressing dominant-negative connexin-43. Upregulation of connexin-43 was observed in tumor cell-endothelial cell contact areas in vitro and in vivo, and in areas of intratumor blood vessels and in micrometastatic foci. Connexin-43 facilitates metastatic 'homing' by increasing adhesion of cancer cells to the lung endothelial cells. The marked upregulation of connexin-43 in tumor cell-endothelial cell contact areas, whether in preexisting 'homing' vessels or in newly formed tumor vessels, suggests that connexin-43 can serve as a potential marker of micrometastases and tumor vasculature and that it may play a role in the early incorporation of endothelial cells into small tumors as seeds for vasculogenesis.

  10. Intercellular adhesion molecules (ICAMs) and spermatogenesis

    PubMed Central

    Xiao, Xiang; Mruk, Dolores D.; Cheng, C. Yan

    2013-01-01

    BACKGROUND During the seminiferous epithelial cycle, restructuring takes places at the Sertoli–Sertoli and Sertoli–germ cell interface to accommodate spermatogonia/spermatogonial stem cell renewal via mitosis, cell cycle progression and meiosis, spermiogenesis and spermiation since developing germ cells, in particular spermatids, move ‘up and down’ the seminiferous epithelium. Furthermore, preleptotene spermatocytes differentiated from type B spermatogonia residing at the basal compartment must traverse the blood–testis barrier (BTB) to enter the adluminal compartment to prepare for meiosis at Stage VIII of the epithelial cycle, a process also accompanied by the release of sperm at spermiation. These cellular events that take place at the opposite ends of the epithelium are co-ordinated by a functional axis designated the apical ectoplasmic specialization (ES)—BTB—basement membrane. However, the regulatory molecules that co-ordinate cellular events in this axis are not known. METHODS Literature was searched at http://www.pubmed.org and http://scholar.google.com to identify published findings regarding intercellular adhesion molecules (ICAMs) and the regulation of this axis. RESULTS Members of the ICAM family, namely ICAM-1 and ICAM-2, and the biologically active soluble ICAM-1 (sICAM-1) are the likely regulatory molecules that co-ordinate these events. sICAM-1 and ICAM-1 have antagonistic effects on the Sertoli cell tight junction-permeability barrier, involved in Sertoli cell BTB restructuring, whereas ICAM-2 is restricted to the apical ES, regulating spermatid adhesion during the epithelial cycle. Studies in other epithelia/endothelia on the role of the ICAM family in regulating cell movement are discussed and this information has been evaluated and integrated into studies of these proteins in the testis to create a hypothetical model, depicting how ICAMs regulate junction restructuring events during spermatogenesis. CONCLUSIONS ICAMs are crucial regulatory molecules of spermatogenesis. The proposed hypothetical model serves as a framework in designing functional experiments for future studies. PMID:23287428

  11. The Lack of Utility of Circulating Biomarkers of Inflammation and Endothelial Dysfunction for Type 2 Diabetes Risk Prediction Among Postmenopausal Women

    PubMed Central

    Chao, Chun; Song, Yiqing; Cook, Nancy; Tseng, Chi-Hong; Manson, JoAnn E.; Eaton, Charles; Margolis, Karen L.; Rodriguez, Beatriz; Phillips, Lawrence S.; Tinker, Lesley F.; Liu, Simin

    2011-01-01

    Background Recent studies have linked plasma markers of inflammation and endothelial dysfunction to type 2 diabetes mellitus (DM) development. However, the utility of these novel biomarkers for type 2 DM risk prediction remains uncertain. Methods The Women’s Health Initiative Observational Study (WHIOS), a prospective cohort, and a nested case-control study within the WHIOS of 1584 incident type 2 DM cases and 2198 matched controls were used to evaluate the utility of plasma markers of inflammation and endothelial dysfunction for type 2 DM risk prediction. Between September 1994 and December 1998, 93 676 women aged 50 to 79 years were enrolled in the WHIOS. Fasting plasma levels of glucose, insulin, white blood cells, tumor necrosis factor receptor 2, interleukin 6, high-sensitivity C-reactive protein, E-selectin, soluble intercellular adhesion molecule 1, and vascular cell adhesion molecule 1 were measured using blood samples collected at baseline. A series of prediction models including traditional risk factors and novel plasma markers were evaluated on the basis of global model fit, model discrimination, net reclassification improvement, and positive and negative predictive values. Results Although white blood cell count and levels of interleukin 6, high-sensitivity C-reactive protein, and soluble intercellular adhesion molecule 1 significantly enhanced model fit, none of the inflammatory and endothelial dysfunction markers improved the ability of model discrimination (area under the receiver operating characteristic curve, 0.93 vs 0.93), net reclassification, or predictive values (positive, 0.22 vs 0.24; negative, 0.99 vs 0.99 [using 15% 6-year type 2 DM risk as the cutoff]) compared with traditional risk factors. Similar results were obtained in ethnic-specific analyses. Conclusion Beyond traditional risk factors, measurement of plasma markers of systemic inflammation and endothelial dysfunction contribute relatively little additional value in clinical type 2 DM risk prediction in a multiethnic cohort of postmenopausal women. PMID:20876407

  12. Loss-of-Function Mutations in SERPINB8 Linked to Exfoliative Ichthyosis with Impaired Mechanical Stability of Intercellular Adhesions.

    PubMed

    Pigors, Manuela; Sarig, Ofer; Heinz, Lisa; Plagnol, Vincent; Fischer, Judith; Mohamad, Janan; Malchin, Natalia; Rajpopat, Shefali; Kharfi, Monia; Lestringant, Giles G; Sprecher, Eli; Kelsell, David P; Blaydon, Diana C

    2016-08-04

    SERPINS comprise a large and functionally diverse family of serine protease inhibitors. Here, we report three unrelated families with loss-of-function mutations in SERPINB8 in association with an autosomal-recessive form of exfoliative ichthyosis. Whole-exome sequencing of affected individuals from a consanguineous Tunisian family and a large Israeli family revealed a homozygous frameshift mutation, c.947delA (p.Lys316Serfs(∗)90), and a nonsense mutation, c.850C>T (p.Arg284(∗)), respectively. These two mutations are located in the last exon of SERPINB8 and, hence, would not be expected to lead to nonsense-mediated decay of the mRNA; nonetheless, both mutations are predicted to lead to loss of the reactive site loop of SERPINB8, which is crucial for forming the SERPINB8-protease complex. Using Sanger sequencing, a homozygous missense mutation, c.2T>C (p.Met1?), predicted to result in an N-terminal truncated protein, was identified in an additional family from UAE. Histological analysis of a skin biopsy from an individual homozygous for the variant p.Arg284(∗) showed disadhesion of keratinocytes in the lower epidermal layers plus decreased SERPINB8 levels compared to control. In vitro studies utilizing siRNA-mediated knockdown of SERPINB8 in keratinocytes demonstrated that in the absence of the protein, there is a cell-cell adhesion defect, particularly when cells are subjected to mechanical stress. In addition, immunoblotting and immunostaining revealed an upregulation of desmosomal proteins. In conclusion, we report mutations in SERPINB8 that are associated with exfoliative ichthyosis and provide evidence that SERPINB8 contributes to the mechanical stability of intercellular adhesions in the epidermis. Copyright © 2016 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  13. Curcumin inhibits activation induced by urban particulate material or titanium dioxide nanoparticles in primary human endothelial cells

    PubMed Central

    Montiel-Dávalos, Angélica; Silva Sánchez, Guadalupe Jazmin; Huerta-García, Elizabeth; Rueda-Romero, Cristhiam; Soca Chafre, Giovanny; Mitre-Aguilar, Irma B.; Alfaro-Moreno, Ernesto; Pedraza-Chaverri, José

    2017-01-01

    Curcumin has protective effects against toxic agents and shows preventive properties for various diseases. Particulate material with an aerodynamic diameter of ≤10 μm (PM10) and titanium dioxide nanoparticles (TiO2-NPs) induce endothelial dysfunction and activation. We explored whether curcumin is able to attenuate different events related to endothelial activation. This includes adhesion, expression of adhesion molecules and oxidative stress induced by PM10 and TiO2-NPs. Human umbilical vein endothelial cells (HUVEC) were treated with 1, 10 and 100 μM curcumin for 1 h and then exposed to PM10 at 3 μg/cm2 or TiO2-NPs at 10 μg/cm2. Cell adhesion was evaluated by co-culture with U937 human myelomonocytic cells. Adhesion molecules expression was measured by flow cytometry after 3 or 24 h of exposure. Oxidative stress was determined by 2,7-dichlorodihydrofluorescein (H2DCF) oxidation. PM10 and TiO2-NPs induced the adhesion of U937 cells and the expression of E- and P-selectins, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and platelet-endothelial cell adhesion molecule-1 (PECAM-1). The expression of E- and P-selectins matched the adhesion of monocytes to HUVEC after 3 h. In HUVEC treated with 1 or 10 μM curcumin, the expression of adhesion molecules and monocytes adhesion was significantly diminished. Curcumin also partially reduced the H2DCF oxidation induced by PM10 and TiO2-NPs. Our results suggest an anti-inflammatory and antioxidant role by curcumin attenuating the activation caused on endothelial cells by exposure to particles. Therefore, curcumin could be useful in the treatment of diseases where an inflammatory process and endothelial activation are involved. PMID:29244817

  14. Thrombomodulin-mediated cell adhesion: involvement of its lectin-like domain.

    PubMed

    Huang, Huey-Chun; Shi, Guey-Yueh; Jiang, Shinn-Jong; Shi, Chung-Sheng; Wu, Chun-Mei; Yang, Hsi-Yuan; Wu, Hua-Lin

    2003-11-21

    Thrombomodulin (TM) is an integral membrane glycoprotein that is a potent anticoagulant factor. TM may also possess functions distinct from its anticoagulant activity. Here the influence of TM on cell adhesion was studied in TM-negative melanoma A2058 cells transfected with green fluorescent protein-tagged TM (TMG) or lectin domain-deleted TM (TMG(DeltaL)). Confocal microscopy demonstrated that both TMG and TMG(DeltaL) were distributed in the plasma membrane. TMG-expressed cells grew as closely clustered colonies, with TM localized prominently in the intercellular boundaries. TMG(DeltaL)-expressed cells grew singly. Overexpression of TMG, but not TMG(DeltaL), decreased monolayer permeability in vitro and tumor growth in vivo. The cell-to-cell adhesion in TMG-expressed cells was Ca2+-dependent and was inhibited by monoclonal antibody against the lectin-like domain of TM. The effects of TM-mediated cell adhesion were abolished by the addition of mannose, chondroitin sulfate A, or chondroitin sulfate C. In addition, anti-lectin-like domain antibody disrupted the close clustering of the endogenous TM-expressed keratinocyte HaCaT cell line derived from normal human epidermis. Double-labeling immunofluorescence staining revealed similar distributions of TM and actin filament in the cortex region of the TMG-expressed cells. Thus, TM can function as a Ca2+-dependent cell-to-cell adhesion molecule. Binding of specific carbohydrates to the lectin-like domain is essential for this specific function.

  15. Low-calorie cranberry juice supplementation reduces plasma oxidized LDL and cell adhesion molecule concentrations in men.

    PubMed

    Ruel, Guillaume; Pomerleau, Sonia; Couture, Patrick; Lemieux, Simone; Lamarche, Benoît; Couillard, Charles

    2008-02-01

    Elevated circulating concentrations of oxidized LDL (OxLDL) and cell adhesion molecules are considered to be relevant markers of oxidative stress and endothelial activation which are implicated in the development of CVD. On the other hand, it has been suggested that dietary flavonoid consumption may be cardioprotective through possible favourable impacts on LDL particle oxidation and endothelial activation. The present study was undertaken to determine the effect of the daily consumption of low-calorie cranberry juice cocktail on plasma OxLDL, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin concentrations in men. Thirty men (mean age 51 (sd 10) years) were recruited and asked to consume increasing daily doses of cranberry juice cocktail (125, 250 and 500 ml/d) over three successive periods of 4 weeks. Plasma OxLDL and adhesion molecule concentrations were measured by ELISA before and after each phase. We noted a significant decrease in plasma OxLDL concentrations following the intervention (P < 0.0001). We also found that plasma ICAM-1 (P < 0.0001) and VCAM-1 (P < 0.05) concentrations decreased significantly during the course of the study. In summary, the present results show that daily cranberry juice cocktail consumption is associated with decreases in plasma OxLDL, ICAM-1 and VCAM-1 concentrations in men.

  16. PLCε1 regulates SDF-1α–induced lymphocyte adhesion and migration to sites of inflammation

    PubMed Central

    Strazza, Marianne; Azoulay-Alfaguter, Inbar; Peled, Michael; Smrcka, Alan V.; Skolnik, Edward Y.; Srivastava, Shekhar; Mor, Adam

    2017-01-01

    Regulation of integrins is critical for lymphocyte adhesion to endothelium and migration throughout the body. Inside-out signaling to integrins is mediated by the small GTPase Ras-proximate-1 (Rap1). Using an RNA-mediated interference screen, we identified phospholipase Cε 1 (PLCε1) as a crucial regulator of stromal cell-derived factor 1 alpha (SDF-1α)-induced Rap1 activation. We have shown that SDF-1α-induced activation of Rap1 is transient in comparison with the sustained level following cross-linking of the antigen receptor. We identified that PLCε1 was necessary for SDF-1α-induced adhesion using shear stress, cell morphology alterations, and crawling on intercellular adhesion molecule 1 (ICAM-1)–expressing cells. Structure–function experiments to separate the dual-enzymatic function of PLCε1 uncover necessary contributions of the CDC25, Pleckstrin homology, and Ras-associating domains, but not phospholipase activity, to this pathway. In the mouse model of delayed type hypersensitivity, we have shown an essential role for PLCε1 in T-cell migration to inflamed skin, but not for cytokine secretion and proliferation in regional lymph nodes. Our results reveal a signaling pathway where SDF-1α induces T-cell adhesion through activation of PLCε1, suggesting that PLCε1 is a specific potential target in treating conditions involving migration of T cells to inflamed organs. PMID:28213494

  17. Endothelial cell SHP-2 negatively regulates neutrophil adhesion and promotes transmigration by enhancing ICAM-1-VE-cadherin interaction.

    PubMed

    Yan, Meiping; Zhang, Xinhua; Chen, Ao; Gu, Wei; Liu, Jie; Ren, Xiaojiao; Zhang, Jianping; Wu, Xiaoxiong; Place, Aaron T; Minshall, Richard D; Liu, Guoquan

    2017-11-01

    Intercellular adhesion molecule-1 (ICAM-1) mediates the firm adhesion of leukocytes to endothelial cells and initiates subsequent signaling that promotes their transendothelial migration (TEM). Vascular endothelial (VE)-cadherin plays a critical role in endothelial cell-cell adhesion, thereby controlling endothelial permeability and leukocyte transmigration. This study aimed to determine the molecular signaling events that originate from the ICAM-1-mediated firm adhesion of neutrophils that regulate VE-cadherin's role as a negative regulator of leukocyte transmigration. We observed that ICAM-1 interacts with Src homology domain 2-containing phosphatase-2 (SHP-2), and SHP-2 down-regulation via silencing of small interfering RNA in endothelial cells enhanced neutrophil adhesion to endothelial cells but inhibited neutrophil transmigration. We also found that VE-cadherin associated with the ICAM-1-SHP-2 complex. Moreover, whereas the activation of ICAM-1 leads to VE-cadherin dissociation from ICAM-1 and VE-cadherin association with actin, SHP-2 down-regulation prevented ICAM-1-VE-cadherin association and promoted VE-cadherin-actin association. Furthermore, SHP-2 down-regulation in vivo promoted LPS-induced neutrophil recruitment in mouse lung but delayed neutrophil extravasation. These results suggest that SHP-2- via association with ICAM-1-mediates ICAM-1-induced Src activation and modulates VE-cadherin switching association with ICAM-1 or actin, thereby negatively regulating neutrophil adhesion to endothelial cells and enhancing their TEM.-Yan, M., Zhang, X., Chen, A., Gu, W., Liu, J., Ren, X., Zhang, J., Wu, X., Place, A. T., Minshall, R. D., Liu, G. Endothelial cell SHP-2 negatively regulates neutrophil adhesion and promotes transmigration by enhancing ICAM-1-VE-cadherin interaction. © FASEB.

  18. Mycophenolate mofetil increases adhesion capacity of tumor cells in vitro.

    PubMed

    Blaheta, Roman A; Bogossian, Harilaos; Beecken, Wolf-Dietrich; Jonas, Dietger; Hasenberg, Christoph; Makarevic, Jasmina; Ogbomo, Henry; Bechstein, Wolf O; Oppermann, Elsie; Leckel, Kerstin; Cinatl, Jindrich

    2003-12-27

    The immunosuppressive drug mycophenolate mofetil (MMF) reduces expression of the heterophilic binding elements intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 and thereby prevents attachment of alloactivated leukocytes to donor endothelium. The authors speculated that MMF might further diminish receptors of the immunoglobulin superfamily which, however, act as homophilic binding elements. Because decrease of homophilic adhesion receptors correlates with tumor dissemination and metastasis, MMF could trigger development or recurrence of neoplastic tumors. The authors analyzed the influence of MMF on homotypic adhesion receptors and its consequence for tumor cell attachment to an endothelial cell monolayer. Neuroblastoma (NB) cells, which self-aggregate by means of the homophilic-binding element neural cell adhesion molecule (NCAM), were used. Effects of MMF on the 140- and 180-kDa NCAM isoforms were investigated quantitatively by flow cytometry, Western blot, and reverse-transcriptase (RT) polymerase chain reaction (PCR). The relevance of NCAM for tumor cell binding was proven by treating NB with NCAM antisense oligonucleotides. MMF profoundly increased the number of adherent NB cells, with a maximum effect at 0.1 microM, compared with controls. Decrease of NCAM on the cell surface was detected by flow cytometry. Western blot and RT-PCR demonstrated reduced protein and RNA levels of the 140- and 180-kDa isoforms. Treatment of NB cells with NCAM antisense oligonucleotides showed that reduced NCAM expression leads to enhanced tumor cell adhesion. MMF decreases NCAM receptors, which is associated with enhanced tumor cell invasiveness. The authors conclude that an MMF-based immunosuppressive regimen might increase the risk of tumor metastasis if this process is predominantly conveyed by means of homophilic adhesion proteins.

  19. Mathematical modeling of cell adhesion in shear flow: application to targeted drug delivery in inflammation and cancer metastasis.

    PubMed

    Jadhav, Sameer; Eggleton, Charles D; Konstantopoulos, Konstantinos

    2007-01-01

    Cell adhesion plays a pivotal role in diverse biological processes that occur in the dynamic setting of the vasculature, including inflammation and cancer metastasis. Although complex, the naturally occurring processes that have evolved to allow for cell adhesion in the vasculature can be exploited to direct drug carriers to targeted cells and tissues. Fluid (blood) flow influences cell adhesion at the mesoscale by affecting the mechanical response of cell membrane, the intercellular contact area and collisional frequency, and at the nanoscale level by modulating the kinetics and mechanics of receptor-ligand interactions. Consequently, elucidating the molecular and biophysical nature of cell adhesion requires a multidisciplinary approach involving the synthesis of fundamentals from hydrodynamic flow, molecular kinetics and cell mechanics with biochemistry/molecular cell biology. To date, significant advances have been made in the identification and characterization of the critical cell adhesion molecules involved in inflammatory disorders, and, to a lesser degree, in cancer metastasis. Experimental work at the nanoscale level to determine the lifetime, interaction distance and strain responses of adhesion receptor-ligand bonds has been spurred by the advent of atomic force microscopy and biomolecular force probes, although our current knowledge in this area is far from complete. Micropipette aspiration assays along with theoretical frameworks have provided vital information on cell mechanics. Progress in each of the aforementioned research areas is key to the development of mathematical models of cell adhesion that incorporate the appropriate biological, kinetic and mechanical parameters that would lead to reliable qualitative and quantitative predictions. These multiscale mathematical models can be employed to predict optimal drug carrier-cell binding through isolated parameter studies and engineering optimization schemes, which will be essential for developing effective drug carriers for delivery of therapeutic agents to afflicted sites of the host.

  20. [Morphological changes in tongue cancer after cryosurgery].

    PubMed

    Zhou, X D; Mao, T Q

    1993-01-01

    Tca 8113 (human tongue cancer cell line) cell transplanted tumors in nude mice were treated with cryosurgery for three freeze-thaw cycles. Tumor samples were obtained by biopsies pre- and post-cryosurgery for morphological study. The results showed intercellular adhesion damage, nuclear pyknosis, cell death, etc. One week after, the deep parts of the frozen samples were similar to that of the untreated ones. Our study indicates the change of biomembrance may be also important as of nuclei in cell death and may play an important role in the treatment of cancer by cryochemistry.

  1. The melanocortin receptor agonist NDP-MSH impairs the allostimulatory function of dendritic cells.

    PubMed

    Rennalls, La'Verne P; Seidl, Thomas; Larkin, James M G; Wellbrock, Claudia; Gore, Martin E; Eisen, Tim; Bruno, Ludovica

    2010-04-01

    As alpha-melanocyte-stimulating hormone (alpha-MSH) is released by immunocompetent cells and has potent immunosuppressive properties, it was determined whether human dendritic cells (DCs) express the receptor for this hormone. Reverse transcription-polymerase chain reaction detected messenger RNA specific for all of the known melanocortin receptors in DCs. Mixed lymphocyte reactions also revealed that treatment with [Nle(4), DPhe(7)]-alpha-MSH (NDP-MSH), a potent alpha-MSH analogue, significantly reduced the ability of DCs to stimulate allogeneic T cells. The expression of various cell surface adhesion, maturation and costimulatory molecules on DCs was also investigated. Although treatment with NDP-MSH did not alter the expression of CD83 and major histocompatibility complex class I and II, the surface expression of CD86 (B7.2), intercellular adhesion molecule (ICAM-1/CD54) and CD1a was reduced. In summary, our data indicate that NDP-MSH inhibits the functional activity of DCs, possibly by down-regulating antigen-presenting and adhesion molecules and that these events may be mediated via the extracellular signal-regulated kinase 1 and 2 pathway.

  2. The effects of platelet activating factor and retinoic acid on the expression of ELAM-1 and ICAM-1 and the functions of neutrophils

    PubMed Central

    1995-01-01

    Preincubation of pulmonary microvascular endothelial cells (PMVECs) with platelet-activating factor (PAF) for 3.5 h increased the adhesion rate of polymorphonuclear leukocytes (PMNs) to PMVECs from 57.3% to 72.8% (p < 0.01). Preincubation of PMNs with PAF also increased PMN-PMVEC adhesion rate. All-trans retinoic acid (RA) blocked the adherence of untreated PMNs to PAF-pretreated PMVECs but not the adherence of PAF-pretreated PMNs to untreated PMVECs. PAF increased the expression of intercellular adhesion molecule-1 (ICAM-1) and E-selection (ELAM-1) on PMVECs, PMN chemotaxis to zymosan-activated serum and histamine, and PMN aggregation and the release of acid phosphatase from PMNs. Co-incubation of RA inhibited PAF-induced PMN aggregation, the release of acid phosphatase from PMNs, and PMN chemotaxis to zymosan-activated serum and histamine while the expression of ICAM-1 and ELAM-1 did not change. Our results suggest that RA can be used to ameliorate PMN-mediated inflammation. PMID:18475624

  3. Arginase-I enhances vascular endothelial inflammation and senescence through eNOS-uncoupling.

    PubMed

    Zhu, Cuicui; Yu, Yi; Montani, Jean-Pierre; Ming, Xiu-Fen; Yang, Zhihong

    2017-02-02

    Augmented arginase-II (Arg-II) is implicated in endothelial senescence and inflammation through a mutual positive regulatory circuit with S6K1. This study was conducted to investigate whether Arg-I, another isoform of arginase that has been also reported to play a role in vascular endothelial dysfunction, promotes endothelial senescence through similar mechanisms. The non-senescent human endothelial cells from umbilical veins (passage 2 to 4) were transduced with empty recombinant adenovirus vector (rAd/CMV) as control or rAd/CMV-Arg-I to overexpress Arg-I. Overexpressing Arg-I promoted eNOS-uncoupling, enhanced senescence markers including p53-S15, p21 and senescence-associated β-galactosidase (SA-β-gal) staining, and increased inflammatory vascular adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) as well as monocyte adhesion to endothelial cells without activating S6K1. All the effects of Arg-I were inhibited by the anti-oxidant N-acetylcysteine (NAC). Our study demonstrates that Arg-I promotes endothelial senescence and inflammatory responses through eNOS-uncoupling unrelated to activation of the S6K1 pathway.

  4. JAM-C regulates tight junctions and integrin-mediated cell adhesion and migration.

    PubMed

    Mandicourt, Guillaume; Iden, Sandra; Ebnet, Klaus; Aurrand-Lions, Michel; Imhof, Beat A

    2007-01-19

    Junctional Adhesion Molecules (JAMs) have been described as major components of tight junctions in endothelial and epithelial cells. Tight junctions are crucial for the establishment and maintenance of cell polarity. During tumor development, they are remodeled, enabling neoplastic cells to escape from constraints imposed by intercellular junctions and to adopt a migratory behavior. Using a carcinoma cell line we tested whether JAM-C could affect tight junctions and migratory properties of tumor cells. We show that transfection of JAM-C improves the tight junctional barrier in tumor cells devoid of JAM-C expression. This is dependent on serine 281 in the cytoplasmic tail of JAM-C because serine mutation into alanine abolishes the specific localization of JAM-C in tight junctions and establishment of cell polarity. More importantly, the same mutation stimulates integrin-mediated cell migration and adhesion via the modulation of beta1 and beta3 integrin activation. These results highlight an unexpected function for JAM-C in controlling epithelial cell conversion from a static, polarized state to a pro-migratory phenotype.

  5. Antibody Against Integrin Lymphocyte Function-Associated Antigen 1 Inhibits HIV Type 1 Infection in Primary Cells Through Caspase-8-Mediated Apoptosis

    PubMed Central

    Walker, Tiffany N.; Cimakasky, Lisa M.; Coleman, Ebony M.; Madison, M. Nia

    2013-01-01

    Abstract HIV-1 infection induces formation of a virological synapse wherein CD4, chemokine receptors, and cell-adhesion molecules such as lymphocyte function-associated antigen 1 (LFA-1) form localized domains on the cell surface. Studies show that LFA-1 on the surface of HIV-1 particles retains its adhesion function and enhances virus attachment to susceptible cells by binding its counterreceptor intercellular adhesion molecule 1 (ICAM-1). This virus–cell interaction augments virus infectivity by facilitating binding and entry events. In this study, we demonstrate that inhibition of the LFA-1/ICAM-1 interaction by a monoclonal antibody leads to decreased virus production and spread in association with increased apoptosis of HIV-infected primary T cells. The data indicate that the LFA-1/ICAM-1 interaction may limit apoptosis in HIV-1-infected T cells. This phenomenon appears similar to anoikis wherein epithelial cells are protected from apoptosis conferred by ligand-bound integrins. These results have implications for further understanding HIV pathogenesis and replication in peripheral compartments and lymphoid organs. PMID:22697794

  6. Activation of cannabinoid CB2 receptor ameliorates atherosclerosis associated with suppression of adhesion molecules.

    PubMed

    Zhao, Yan; Yuan, Zuyi; Liu, Yan; Xue, Jiahong; Tian, Yuling; Liu, Weimin; Zhang, Weiping; Shen, Yan; Xu, Wei; Liang, Xiao; Chen, Tao

    2010-03-01

    Adhesion molecules have been implicated in the development and progression of atherosclerosis. Cannabinoids have been reported to modulate the migration and adhesion molecules expression of various cell types. Here we examined the effects of WIN55212-2, a cannabinoid receptor 1 (CB1-R)/cannabinoid receptor 2 (CB2-R) agonist on the development of atherosclerotic lesions in apolipoprotein E-deficient (ApoE-/-) mice, which are vulnerable because of their high plasma cholesterol and triacylglycerol levels, focusing on the expression of endothelial adhesion molecules. In the aorta of ApoE-/- mice, WIN55212-2 significantly reduced aortic root plaque area. The mechanism for this seemed to be reduced infiltration of macrophages into the atherosclerotic plaque which was also associated with reduced expression of vascular cellular adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and P-selectin in the aorta. In vitro studies revealed reduced cell adhesion of a monocytic cell line (U937) to human umbilical vein endothelial cells after incubation with WIN55212-2. The reduction in macrophage adhesion also correlated with significant reductions in the expression of VCAM-1, ICAM-1, and P-selectin, indicating that reduced infiltration of macrophages in atherosclerotic plaques may occur as a result of the direct effect of WIN55212-2 on adhesion molecules in macrophages and endothelial cells. In conclusion, WIN55212-2 seems to have direct anti-atherosclerotic effects in an animal model of atherosclerosis. These effects were at least partly due to effects on the expression of VCAM-1, ICAM-1, and P-selectin, which led to reduced macrophage adhesion and infiltration. Furthermore, the protective effects completely blocked by the highly selective CB2 receptor antagonist AM630 suggest that these beneficial effects of WIN55212-2 may be mediated through the CB2 receptor.

  7. Epigallocatechin 3-gallate inhibits 7-ketocholesterol-induced monocyte-endothelial cell adhesion.

    PubMed

    Yamagata, Kazuo; Tanaka, Noriko; Suzuki, Koichi

    2013-07-01

    7-Ketocholesterol (7KC) induces monocytic adhesion to endothelial cells, and induces arteriosclerosis while high-density lipoprotein (HDL) inhibits monocytic adhesion to the endothelium. Epigallocatechin 3-gallate (EGCG) was found to have a protective effect against arteriosclerosis. Therefore, the purpose of this study was to examine the possible HDL-like mechanisms of EGCG in endothelial cells by investigating whether EGCG inhibits 7KC-induced monocyte-endothelial cell adhesion by activating HDL-dependent signal transduction pathways. 7KC and/or EGCG were added to human endothelial cells (ISO-HAS), and the adhesion of pro-monocytic U937 cells was examined. The expression of genes associated with HDL effects such as Ca(2+)/calmodulin-dependent kinase II (CaMKKII), liver kinase B (LKD1), PSD-95/Dlg/ZO-1 kinase 1 (PDZK1), phosphatidylinositol 3-kinase (PI3K), intercellular adhesion molecule-1 (ICAM-1), monocyte chemotactic protein-1 (MCP-1), and endothelial nitric oxide synthase (eNOS) was examined by RT-PCR, and ICAM-1 protein expression was evaluated by western blot (WB). Production of reactive oxygen species (ROS) was examined with H2DCFDA. 7KC significantly induced adhesion of U937 cells to human endothelial cells while significantly increasing gene expressions of ICAM-1 and MCP-1 and decreasing eNOS and CaMKKII gene expressions. EGCG inhibited 7KC-induced monocytic adhesion to endothelial cells, and induced expression of eNOS and several genes involved in the CaMKKII pathway. Stimulation of endothelial cells with EGCG produced intracellular ROS, whereas treatment with N-acetylcysteine (NAC) blocked EGCG-induced expression of eNOS and CaMKKII. These results suggest that inhibition of monocyte-endothelial cell adhesion by EGCG is associated with CaMKKII pathway activation by ROS. Inhibition of 7KC-induced monocyte-endothelial cell adhesion induced by EGCG may function similarly to HDL. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Bronchial biopsy evidence for leukocyte infiltration and upregulation of leukocyte-endothelial cell adhesion molecules 6 hours after local allergen challenge of sensitized asthmatic airways.

    PubMed Central

    Montefort, S; Gratziou, C; Goulding, D; Polosa, R; Haskard, D O; Howarth, P H; Holgate, S T; Carroll, M P

    1994-01-01

    We have examined the mucosal changes occurring in bronchial biopsies from six atopic asthmatics 5-6 h after local endobronchial allergen challenge and compared them with biopsies from saline-challenged segments from the same subjects at the same time point. All the subjects developed localized bronchoconstriction in the allergen-challenged segment and had a decrease in forced expiratory volume in 1 s (FEV1) (P < 0.01) and a decrease in their methacholine provocative concentration of agonist required to reduce FEV1 from baseline by 20% (P < 0.05) 24 h postchallenge. At 6 h we observed an increase in neutrophils (P = 0.03), eosinophils (P = 0.025), mast cells (P = 0.03), and CD3+ lymphocytes (P = 0.025), but not in CD4+ or CD8+ lymphocyte counts. We also detected an increase in endothelial intercellular adhesion molecule type 1 (P < 0.05) and E-selectin (P < 0.005), but not vascular cell adhesion molecule type 1 expression with a correlative increase in submucosal and epithelial LFA+ leucocytes (P < 0.01). Thus, in sensitized asthmatics, local endobronchial allergen instillation leads to an increased inflammatory cell infiltrate of the airway mucosa that involves upregulation of specific adhesion molecules expressed on the microvasculature. Images PMID:7512980

  9. Coaction of intercellular adhesion and cortical tension specifies tissue surface tension

    PubMed Central

    Manning, M. Lisa; Foty, Ramsey A.; Steinberg, Malcolm S.; Schoetz, Eva-Maria

    2010-01-01

    In the course of animal morphogenesis, large-scale cell movements occur, which involve the rearrangement, mutual spreading, and compartmentalization of cell populations in specific configurations. Morphogenetic cell rearrangements such as cell sorting and mutual tissue spreading have been compared with the behaviors of immiscible liquids, which they closely resemble. Based on this similarity, it has been proposed that tissues behave as liquids and possess a characteristic surface tension, which arises as a collective, macroscopic property of groups of mobile, cohering cells. But how are tissue surface tensions generated? Different theories have been proposed to explain how mesoscopic cell properties such as cell–cell adhesion and contractility of cell interfaces may underlie tissue surface tensions. Although recent work suggests that both may be contributors, an explicit model for the dependence of tissue surface tension on these mesoscopic parameters has been missing. Here we show explicitly that the ratio of adhesion to cortical tension determines tissue surface tension. Our minimal model successfully explains the available experimental data and makes predictions, based on the feedback between mechanical energy and geometry, about the shapes of aggregate surface cells, which we verify experimentally. This model indicates that there is a crossover from adhesion dominated to cortical-tension dominated behavior as a function of the ratio between these two quantities. PMID:20616053

  10. Inhibition of STAT3 phosphorylation by sulforaphane reduces adhesion molecule expression in vascular endothelial cell.

    PubMed

    Cho, Young S; Kim, Chan H; Ha, Tae S; Ahn, Hee Y

    2015-11-18

    Intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) play key roles in the initiation of vascular inflammation. In this study, we explored whether sulforaphane, a dietary phytochemical, can inhibit the expression of ICAM-1 and VCAM-1 in human umbilical vein endothelial cells (HUVEC) stimulated with lipopolysaccharide (LPS), and the mechanisms involved. Sulforaphane prevented the LPS-mediated increase in ICAM-1 and VCAM-1 expression, (P < 0.01) in HUVEC. Sulforaphane also prevented the LPS-mediated increase in the phosphorylation of signal transducer and activator of transcription 3 (STAT3) (P < 0.01). Stattic, a STAT3 inhibitor, reduced the LPS-induced expression of ICAM-1 and VCAM-1, and STAT3 phosphorylation (P < 0.01). STAT3 small interfering RNA treatment reduced the LPS-induced expression of ICAM-1, VCAM-1, and STAT3 (P < 0.01). Sulforaphane reduced LPS-mediated THP-1 monocyte adhesion to HUVEC (P < 0.01). In C57BL/6 mice, injection of LPS increased aortic ICAM-1 and VCAM-1 expression, and this effect was prevented by sulforaphane. These data provide insight into the mechanism through which sulforaphane partly reduces the expression of ICAM-1 and VCAM-1 on the vascular wall by inhibiting STAT3 phosphorylation.

  11. Morphological alterations of T24 cells on flat and nanotubular TiO2 surfaces.

    PubMed

    Imani, Roghayeh; Kabaso, Doron; Erdani Kreft, Mateja; Gongadze, Ekaterina; Penic, Samo; Elersic, Kristina; Kos, Andrej; Veranic, Peter; Zorec, Robert; Iglic, Ales

    2012-12-01

    To investigate morphological alterations of malignant cancer cells (T24) of urothelial origin seeded on flat titanium (Ti) and nanotubular TiO(2) (titanium dioxide) nanostructures. Using anodization method, TiO(2) surfaces composed of vertically aligned nanotubes of 50-100 nm diameters were produced. The flat Ti surface was used as a reference. The alteration in the morphology of cancer cells was evaluated using scanning electron microscopy (SEM). A computational model, based on the theory of membrane elasticity, was constructed to shed light on the biophysical mechanisms responsible for the observed changes in the contact area of adhesion. Large diameter TiO(2) nanotubes exhibited a significantly smaller contact area of adhesion (P<0.0001) and had more membrane protrusions (eg, microvilli and intercellular membrane nanotubes) than on flat Ti surface. Numerical membrane dynamics simulations revealed that the low adhesion energy per unit area would hinder the cell spreading on the large diameter TiO(2) nanotubular surface, thus explaining the small contact area. The reduction in the cell contact area in the case of large diameter TiO(2) nanotube surface, which does not enable formation of the large enough number of the focal adhesion points, prevents spreading of urothelial cells.

  12. Hug tightly and say goodbye: role of endothelial ICAM-1 in leukocyte transmigration.

    PubMed

    Rahman, Arshad; Fazal, Fabeha

    2009-04-01

    Stable adhesion of leukocytes to endothelium is crucial for transendothelial migration (TEM) of leukocytes evoked during inflammatory responses, immune surveillance, and homing and mobilization of hematopoietic progenitor cells. The basis of stable adhesion involves expression of intercellular adhesion molecule-1 (ICAM-1), an inducible endothelial adhesive protein that serves as a counter-receptor for beta(2)-integrins on leukocytes. Interaction of ICAM-1 with beta(2)-integrins enables leukocytes to adhere firmly to the vascular endothelium and subsequently, to migrate across the endothelial barrier. The emerging paradigm is that ICAM-1, in addition to firmly capturing leukocytes, triggers intracellular signaling events that may contribute to active participation of the endothelium in facilitating the TEM of adherent leukocytes. The nature, duration, and intensity of ICAM-1-dependent signaling events may contribute to the determination of the route (paracellular vs. transcellular) of leukocyte passage; these aspects of ICAM-1 signaling may in turn be influenced by density and distribution of ICAM-1 on the endothelial cell surface, the source of endothelial cells it is present on, and the type of leukocytes with which it is engaged. This review summarizes our current understanding of the "ICAM-1 paradigm" of TEM with an emphasis on the signaling events mediating ICAM-1 expression and activated by ICAM-1 engagement in endothelial cells.

  13. On the self-association potential of transmembrane tight junction proteins.

    PubMed

    Blasig, I E; Winkler, L; Lassowski, B; Mueller, S L; Zuleger, N; Krause, E; Krause, G; Gast, K; Kolbe, M; Piontek, J

    2006-02-01

    Tight junctions seal intercellular clefts via membrane-related strands, hence, maintaining important organ functions. We investigated the self-association of strand-forming transmembrane tight junction proteins. The regulatory tight junction protein occludin was differently tagged and cotransfected in eucaryotic cells. These occludins colocalized within the plasma membrane of the same cell, coprecipitated and exhibited fluorescence resonance energy transfer. Differently tagged strand-forming claudin-5 also colocalized in the plasma membrane of the same cell and showed fluorescence resonance energy transfer. This demonstrates self-association in intact cells both of occludin and claudin-5 in one plasma membrane. In search of dimerizing regions of occludin, dimerization of its cytosolic C-terminal coiledcoil domain was identified. In claudin-5, the second extracellular loop was detected as a dimer. Since the transmembrane junctional adhesion molecule also is known to dimerize, the assumption that homodimerization of transmembrane tight junction proteins may serve as a common structural feature in tight junction assembly is supported.

  14. Pseudorabies Virus US3-Induced Tunneling Nanotubes Contain Stabilized Microtubules, Interact with Neighboring Cells via Cadherins, and Allow Intercellular Molecular Communication

    PubMed Central

    Jansens, Robert J. J.; Van den Broeck, Wim; De Pelsmaeker, Steffi; Lamote, Jochen A. S.; Van Waesberghe, Cliff; Couck, Liesbeth

    2017-01-01

    ABSTRACT Tunneling nanotubes (TNTs) are long bridge-like structures that connect eukaryotic cells and mediate intercellular communication. We found earlier that the conserved alphaherpesvirus US3 protein kinase induces long cell projections that contact distant cells and promote intercellular virus spread. In this report, we show that the US3-induced cell projections constitute TNTs. In addition, we report that US3-induced TNTs mediate intercellular transport of information (e.g., green fluorescent protein [GFP]) in the absence of other viral proteins. US3-induced TNTs are remarkably stable compared to most TNTs described in the literature. In line with this, US3-induced TNTs were found to contain stabilized (acetylated and detyrosinated) microtubules. Transmission electron microscopy showed that virus particles are individually transported in membrane-bound vesicles in US3-induced TNTs and are released along the TNT and at the contact area between a TNT and the adjacent cell. Contact between US3-induced TNTs and acceptor cells is very stable, which correlated with a marked enrichment in adherens junction components beta-catenin and E-cadherin at the contact area. These data provide new structural insights into US3-induced TNTs and how they may contribute to intercellular communication and alphaherpesvirus spread. IMPORTANCE Tunneling nanotubes (TNT) represent an important and yet still poorly understood mode of long-distance intercellular communication. We and others reported earlier that the conserved alphaherpesvirus US3 protein kinase induces long cellular protrusions in infected and transfected cells. Here, we show that US3-induced cell projections constitute TNTs, based on structural properties and transport of biomolecules. In addition, we report on different particular characteristics of US3-induced TNTs that help to explain their remarkable stability compared to physiological TNTs. In addition, transmission electron microscopy assays indicate that, in infected cells, virions travel in the US3-induced TNTs in membranous transport vesicles and leave the TNT via exocytosis. These data generate new fundamental insights into the biology of (US3-induced) TNTs and into how they may contribute to intercellular virus spread and communication. PMID:28747498

  15. Natural Hemozoin Stimulates Syncytiotrophoblast to Secrete Chemokines and Recruit Peripheral Blood Mononuclear Cells

    PubMed Central

    Lucchi, Naomi W.; Sarr, Demba; Owino, Simon O.; Mwalimu, Stephen M.; Peterson, David S.; Moore, Julie M.

    2011-01-01

    Background Placental malaria is associated with local accumulation of parasitized erythrocytes, deposition of the parasite hemoglobin metabolite, hemozoin, and accumulation of mononuclear cells in the intervillous space. Fetal syncytiotrophoblast cells in contact with maternal blood are known to respond immunologically to cytoadherent Plasmodium falciparum-infected erythrocytes, but their responsiveness to hemozoin, a potent pro-inflammatory stimulator of monocytes, macrophages and dendritic cells, is not known. Methods The biochemical and immunological changes induced in primary syncytiotrophoblast by natural hemozoin was assessed. Changes in syncytiotrophoblast mitogen-activated protein kinase activation was assessed by immunoblotting and secreted cytokine and chemokine proteins were assayed by ELISA. Chemotaxis of peripheral blood mononuclear cells was assessed using a two-chamber assay system and flow cytometry was used to assess the activation of primary monocytes by hemozoin-stimulated syncytiotrophoblast conditioned medium. Results Hemozoin stimulation induced ERK1/2 phosphorylation. Treated cells secreted CXCL8, CCL3, CCL4, and tumor necrosis factor and released soluble intercellular adhesion molecule-1. Furthermore, the dependence of the hemozoin responses on ERK1/2 stimulation was confirmed by inhibition of chemokine release in syncytiotrophoblast treated with an ERK pathway inhibitor. Hemozoin-stimulated cells elicited the specific migration of PBMCs, and conditioned medium from the cells induced the upregulation of intercellular adhesion molecule-1 on primary monocytes. Conclusions These findings confirm an immunostimulatory role for hemozoin and expand the cell types known to be responsive to hemozoin to include fetal syncytiotrophoblast. The results provide further evidence that syncytiotrophoblast cells can influence the local maternal immune response to placental malaria. PMID:21632106

  16. Low-molecular-weight hyaluronan (LMW-HA) accelerates lymph node metastasis of melanoma cells by inducing disruption of lymphatic intercellular adhesion.

    PubMed

    Du, Yan; Cao, Manlin; Liu, Yiwen; He, Yiqing; Yang, Cuixia; Wu, Man; Zhang, Guoliang; Gao, Feng

    2016-01-01

    Endothelial integrity defects initiate lymphatic metastasis of tumor cells. Low-molecular-weight hyaluronan (LMW-HA) derived from plasma and interstitial fluid was reported to be associated with tumor lymphatic metastasis. In addition, LMW-HA was proved to disrupt lymphatic vessel endothelium integrity, thus promoting lymphatic metastasis of tumor cells. Until now, there are few reports on how LMW-HA modulates lymphatic endothelial cells adhesion junctions and affects cancer cells metastasizing into lymph vessels. The aim of our study is to unravel the novel mechanism of LMW-HA in mediating tumor lymphatic metastasis. Here, we employed a melanoma metastasis model to investigate whether LMW-HA facilitates tumor cells transferring from foci to remote lymph nodes by disrupting the lymphatic endothelial integrity. Our data indicate that LMW-HA significantly induces metastasis of melanoma cells to lymph nodes and accelerates interstitial-lymphatic flow in vivo . Further experiments show that increased migration of melanoma cells across human dermal lymphatic endothelial cell (HDLEC) monolayers is accompanied by impaired lymphatic endothelial barrier function and increased permeability. The mechanism study reveals that VE-cadherin-β-catenin pathway and relevant signals are involved in modulating the interactions between endothelial cells and that a significant inhibition of lymphatic endothelium disruption is observed when antibodies to the LMW-HA receptor (LYVE-1) are present. Thus, our findings demonstrate a disruptive effect of LMW-HA on lymphatic endothelium continuity which leads to a promotion on melanoma lymphatic metastasis and also suggest a cellular signaling mechanism associated with VE-cadherin-mediated lymphatic intercellular junctions.

  17. Cyclic Stretching of Mesangial Cells Up-Regulates Intercellular Adhesion Molecule-1 and Leukocyte Adherence

    PubMed Central

    Riser, Bruce L.; Varani, James; Cortes, Pedro; Yee, Jerry; Dame, Michael; Sharba, Abdul K.

    2001-01-01

    Intraglomerular hypertension is a primary causal factor in the progressive glomerulosclerosis that characterizes diabetic nephropathy or severe renal ablation. However, inflammation of the glomerular mesangium also participates in at least the early phase of these diseases. In glomerulonephritis, where inflammation is thought to be the predominant causal factor, intraglomerular hypertension is also often present. Mesangial cells (MCs) are critical in orchestrating key functions of the glomerulus including extracellular matrix metabolism, cytokine production, and interaction with leukocytes. Because MCs are subject to increased stretching when intraglomerular hypertension is present, and in glomerulonephritis MC/leukocyte interactions seem to be mediated primarily via the up-regulation of intercellular adhesion molecule-1 (ICAM-1), we examine the possibility that cyclic stretching is a stimulus for increased MC ICAM-1 activity. We demonstrate that the normal low levels of MC ICAM-1 mRNA and protein are dramatically up-regulated by even short intervals of cyclic stretch. This effect is dose- and time-dependent, and requires little amplitude and a brief period of elongation for significant induction. Stretch-induced MC ICAM-1 also leads to a marked elevation in phagocytic leukocyte adherence. This stimulated adherence is equal or greater than that induced by the inflammatory cytokine tumor necrosis factor-α, whereas an additive effect occurs when both are applied in combination. Our results indicate that stretch-induced ICAM-1 may provide a direct link between hypertension and inflammation in the progression of injury and glomerulosclerosis in diabetes, renal ablation, and other forms of glomerulonephritis. PMID:11141473

  18. Cyclic stretching of mesangial cells up-regulates intercellular adhesion molecule-1 and leukocyte adherence: a possible new mechanism for glomerulosclerosis.

    PubMed

    Riser, B L; Varani, J; Cortes, P; Yee, J; Dame, M; Sharba, A K

    2001-01-01

    Intraglomerular hypertension is a primary causal factor in the progressive glomerulosclerosis that characterizes diabetic nephropathy or severe renal ablation. However, inflammation of the glomerular mesangium also participates in at least the early phase of these diseases. In glomerulonephritis, where inflammation is thought to be the predominant causal factor, intraglomerular hypertension is also often present. Mesangial cells (MCs) are critical in orchestrating key functions of the glomerulus including extracellular matrix metabolism, cytokine production, and interaction with leukocytes. Because MCs are subject to increased stretching when intraglomerular hypertension is present, and in glomerulonephritis MC/leukocyte interactions seem to be mediated primarily via the up-regulation of intercellular adhesion molecule-1 (ICAM-1), we examine the possibility that cyclic stretching is a stimulus for increased MC ICAM-1 activity. We demonstrate that the normal low levels of MC ICAM-1 mRNA and protein are dramatically up-regulated by even short intervals of cyclic stretch. This effect is dose- and time-dependent, and requires little amplitude and a brief period of elongation for significant induction. Stretch-induced MC ICAM-1 also leads to a marked elevation in phagocytic leukocyte adherence. This stimulated adherence is equal or greater than that induced by the inflammatory cytokine tumor necrosis factor-alpha, whereas an additive effect occurs when both are applied in combination. Our results indicate that stretch-induced ICAM-1 may provide a direct link between hypertension and inflammation in the progression of injury and glomerulosclerosis in diabetes, renal ablation, and other forms of glomerulonephritis.

  19. Dietary sodium, adiposity, and inflammation in healthy adolescents.

    PubMed

    Zhu, Haidong; Pollock, Norman K; Kotak, Ishita; Gutin, Bernard; Wang, Xiaoling; Bhagatwala, Jigar; Parikh, Samip; Harshfield, Gregory A; Dong, Yanbin

    2014-03-01

    To determine the relationships of sodium intake with adiposity and inflammation in healthy adolescents. A cross-sectional study involved 766 healthy white and African American adolescents aged 14 to 18 years. Dietary sodium intake was estimated by 7-day 24-hour dietary recall. Percent body fat was measured by dual-energy x-ray absorptiometry. Subcutaneous abdominal adipose tissue and visceral adipose tissue were assessed using magnetic resonance imaging. Fasting blood samples were measured for leptin, adiponectin, C-reactive protein, tumor necrosis factor-α, and intercellular adhesion molecule-1. The average sodium intake was 3280 mg/day. Ninety-seven percent of our adolescents exceeded the American Heart Association recommendation for sodium intake. Multiple linear regressions revealed that dietary sodium intake was independently associated with body weight (β = 0.23), BMI (β = 0.23), waist circumference (β = 0.23), percent body fat (β = 0.17), fat mass (β = 0.23), subcutaneous abdominal adipose tissue (β = 0.25), leptin (β = 0.20), and tumor necrosis factor-α (β = 0.61; all Ps < .05). No relation was found between dietary sodium intake and visceral adipose tissue, skinfold thickness, adiponectin, C-reactive protein, or intercellular adhesion molecule-1. All the significant associations persisted after correction for multiple testing (all false discovery rates < 0.05). The mean sodium consumption of our adolescents is as high as that of adults and more than twice the daily intake recommended by the American Heart Association. High sodium intake is positively associated with adiposity and inflammation independent of total energy intake and sugar-sweetened soft drink consumption.

  20. Dietary Sodium, Adiposity, and Inflammation in Healthy Adolescents

    PubMed Central

    Pollock, Norman K.; Kotak, Ishita; Gutin, Bernard; Wang, Xiaoling; Bhagatwala, Jigar; Parikh, Samip; Harshfield, Gregory A.; Dong, Yanbin

    2014-01-01

    OBJECTIVES: To determine the relationships of sodium intake with adiposity and inflammation in healthy adolescents. METHODS: A cross-sectional study involved 766 healthy white and African American adolescents aged 14 to 18 years. Dietary sodium intake was estimated by 7-day 24-hour dietary recall. Percent body fat was measured by dual-energy x-ray absorptiometry. Subcutaneous abdominal adipose tissue and visceral adipose tissue were assessed using magnetic resonance imaging. Fasting blood samples were measured for leptin, adiponectin, C-reactive protein, tumor necrosis factor-α, and intercellular adhesion molecule-1. RESULTS: The average sodium intake was 3280 mg/day. Ninety-seven percent of our adolescents exceeded the American Heart Association recommendation for sodium intake. Multiple linear regressions revealed that dietary sodium intake was independently associated with body weight (β = 0.23), BMI (β = 0.23), waist circumference (β = 0.23), percent body fat (β = 0.17), fat mass (β = 0.23), subcutaneous abdominal adipose tissue (β = 0.25), leptin (β = 0.20), and tumor necrosis factor-α (β = 0.61; all Ps < .05). No relation was found between dietary sodium intake and visceral adipose tissue, skinfold thickness, adiponectin, C-reactive protein, or intercellular adhesion molecule-1. All the significant associations persisted after correction for multiple testing (all false discovery rates < 0.05). CONCLUSIONS: The mean sodium consumption of our adolescents is as high as that of adults and more than twice the daily intake recommended by the American Heart Association. High sodium intake is positively associated with adiposity and inflammation independent of total energy intake and sugar-sweetened soft drink consumption. PMID:24488738

  1. Morphological evaluation of tongue mucosa in burning mouth syndrome.

    PubMed

    Sardella, Andrea; Gualerzi, Alice; Lodi, Giovanni; Sforza, Chiarella; Carrassi, Antonio; Donetti, Elena

    2012-01-01

    The aim of the present study was to perform a morphological evaluation by immunofluorescence of biomarkers of keratinocyte intercellular adhesion, and of differentiation in the tongue mucosa of burning mouth syndrome patients (BMS), compared with a control group. A prospective blinded evaluation of tongue mucosal specimens processed for light microscopy was performed. Intercellular adhesion was evaluated by investigating the expression of desmoglein 1, desmoglein 3, and of occludin. Keratin 10 and keratin 14 (markers of epithelial differentiation) were also evaluated, as keratin 16 (marker for activated keratinocytes after epithelial injury). Apoptotic cascade was investigated by p53 and activated caspase-3 expression. The basal membrane integrity was analysed through laminin immunoreactivity. In both groups, a preserved three-dimensional architecture of the tongue was observed. Desmoglein 1 and desmoglein 3 epithelial distributions were similar in the desmosomes of patients and control subjects. Again, keratin 10 immunoreactivity and distribution pattern of keratin 14 in the epithelial compartment was similar in both groups. In control samples, keratin 16 immunoreactivity was scant throughout the epithelium with a punctuate and scattered cytoplasmic labelling. In contrast, in all BMS patients keratinocyte cytoplasm was homogeneously labelled for keratin 16, with a more intense staining than controls. Furthermore, keratin 16 staining progressively decreased proceeding towards the most superficial epithelial layers. The results of this study are consistent with and support the clinically normal features of oral mucosa in BMS, and suggest that keratin 16 may be involved in the cell mechanisms underlying the syndrome occurrence. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Antibody to a conserved antigenic target is protective against diverse prokaryotic and eukaryotic pathogens

    PubMed Central

    Cywes-Bentley, Colette; Skurnik, David; Zaidi, Tanweer; Roux, Damien; DeOliveira, Rosane B.; Garrett, Wendy S.; Lu, Xi; O’Malley, Jennifer; Kinzel, Kathryn; Zaidi, Tauqeer; Rey, Astrid; Perrin, Christophe; Fichorova, Raina N.; Kayatani, Alexander K. K.; Maira-Litràn, Tomas; Gening, Marina L.; Tsvetkov, Yury E.; Nifantiev, Nikolay E.; Bakaletz, Lauren O.; Pelton, Stephen I.; Golenbock, Douglas T.; Pier, Gerald B.

    2013-01-01

    Microbial capsular antigens are effective vaccines but are chemically and immunologically diverse, resulting in a major barrier to their use against multiple pathogens. A β-(1→6)–linked poly-N-acetyl-d-glucosamine (PNAG) surface capsule is synthesized by four proteins encoded in genetic loci designated intercellular adhesion in Staphylococcus aureus or polyglucosamine in selected Gram-negative bacterial pathogens. We report that many microbial pathogens lacking an identifiable intercellular adhesion or polyglucosamine locus produce PNAG, including Gram-positive, Gram-negative, and fungal pathogens, as well as protozoa, e.g., Trichomonas vaginalis, Plasmodium berghei, and sporozoites and blood-stage forms of Plasmodium falciparum. Natural antibody to PNAG is common in humans and animals and binds primarily to the highly acetylated glycoform of PNAG but is not protective against infection due to lack of deposition of complement opsonins. Polyclonal animal antibody raised to deacetylated glycoforms of PNAG and a fully human IgG1 monoclonal antibody that both bind to native and deacetylated glycoforms of PNAG mediated complement-dependent opsonic or bactericidal killing and protected mice against local and/or systemic infections by Streptococcus pyogenes, Streptococcus pneumoniae, Listeria monocytogenes, Neisseria meningitidis serogroup B, Candida albicans, and P. berghei ANKA, and against colonic pathology in a model of infectious colitis. PNAG is also a capsular polysaccharide for Neisseria gonorrhoeae and nontypable Hemophilus influenzae, and protects cells from environmental stress. Vaccination targeting PNAG could contribute to immunity against serious and diverse prokaryotic and eukaryotic pathogens, and the conserved production of PNAG suggests that it is a critical factor in microbial biology. PMID:23716675

  3. Interaction between hyaluronan and CD44 in the development of dimethylnitrosamine-induced liver cirrhosis.

    PubMed

    Satoh, T; Ichida, T; Matsuda, Y; Sugiyama, M; Yonekura, K; Ishikawa, T; Asakura, H

    2000-04-01

    A significant increase in serum hyaluronan (HA) levels has been reported in patients with liver cirrhosis. This mechanism is not yet clear, and receptors for HA have not been characterized. In this study, we examined the expression of both HA and its receptors, CD44 and intercellular adhesion molecule-1 (ICAM-1), in dimethylnitrosamine-induced liver cirrhosis. Using biotinylated HA binding protein, HA was detected in the area of periportal fibrosis and around the sinusoidal wall where hepatic fibrosis was developing. Electron microscopy revealed that HA was localized on Ito cells and sinusoidal endothelial cells (SEC). Conversely, CD44, which was only expressed weakly in normal liver, was present in large amounts in cirrhotic liver. The distribution pattern of CD44 was similar to that of HA, however, CD44 was mainly localized on the infiltrating lymphocytes and Kupffer cells. Moreover, CD44 was detected on part of factor VIII-positive SEC. Intercellular adhesion molecule-1, another receptor for HA, was detected on the surface of hepatocytes and around the sinusoidal wall in cirrhotic liver, but its distribution was not accompanied by expression of HA. With respect to CD44 isoforms, the standard form m-RNA predominated in both normal and cirrhotic liver. Variant pMeta-1 mRNA was detected at low levels. An interaction between HA and CD44 may play a role in the recruitment of numerous infiltrating cells and HA accumulation in hepatic sinusoids. Together with phenotypic changes in the SEC, these results may lead to a disturbance in the elimination of HA during the progression of liver cirrhosis.

  4. Progression of symptomatic intracranial large artery atherosclerosis is associated with a proinflammatory state and impaired fibrinolysis.

    PubMed

    Arenillas, Juan F; Alvarez-Sabín, José; Molina, Carlos A; Chacón, Pilar; Fernández-Cadenas, Israel; Ribó, Marc; Delgado, Pilar; Rubiera, Marta; Penalba, Anna; Rovira, Alex; Montaner, Joan

    2008-05-01

    The molecular pathways involved in the progression of intracranial large artery atherosclerosis (ILA) are largely unknown. Our objective was to prospectively study the relationship between circulating levels of inflammatory markers and fibrinolysis inhibitors, and the risk of progression of symptomatic ILA. Seventy-five consecutive patients with first-ever symptomatic intracranial atherostenosis were studied. Blood levels of C-reactive protein (CRP), E-selectin, monocyte chemoattractant protein-1, intercellular adhesion molecule-1, matrix metalloproteinases 1, 2, 3, 8, 9, 10, and 13, plasminogen activator inhibitor-1 (PAI-1), and lipoprotein(a) were measured 3 months after the qualifying stroke or transient ischemic attack. Thereafter, patients underwent long-term transcranial Doppler follow-up to detect progression of ILA. During a median follow-up time of 23 months, 25 (33%) patients showed ILA progression. Multivariable adjusted Cox regression models and Kaplan-Meier curves showed that high baseline level of CRP, E-selectin, intercellular adhesion molecule-1, matrix metalloproteinase 9, PAI-1, and lipoprotein(a) predicted ILA progression independently of vascular risk factors. Of them, only CRP (CRP>5.5 mg/L; HR, 5.4 [2.3 to 12.7]; P=0.0001) and PAI-1 (PAI-1>23.1 ng/mL; HR, 2.4 [1.0 to 5.8]; P=0.05) predicted ILA progression also independently of the other studied molecules. Progression of symptomatic ILA is associated with a proinflammatory state, as reflected by high levels of inflammatory markers, and with defective fibrinolysis, as indicated by raised concentrations of endogenous fibrinolysis inhibitors.

  5. Advanced glycation end products and the progressive course of renal disease.

    PubMed

    Heidland, A; Sebekova, K; Schinzel, R

    2001-10-01

    In experimental and human diabetic nephropathy (DN), it has been shown that advanced glycation end products (AGEs), in particular, carboxymethyl-lysine and pentosidine, accumulate with malondialdehyde in glomerular lesions in relation to disease severity and in the presence of an upregulated receptor for AGE (RAGE) in podocytes. Toxic effects of AGEs result from structural and functional alterations in plasma and extracellular matrix (ECM) proteins, in particular, from cross-linking of proteins and interaction of AGEs with their receptors and/or binding proteins. In mesangial and endothelial cells, the AGE-RAGE interaction caused enhanced formation of oxygen radicals with subsequent activation of nuclear factor-kappaB and release of pro-inflammatory cytokines (interleukin-6, tumor necrosis factor-alpha), growth factors (transforming growth factor-beta1 [TGF-beta1], insulin-like growth factor-1), and adhesion molecules (vascular cell adhesion molecule-1, intercellular adhesion molecule-1). In tubular cells, incubation with AGE albumin was followed by stimulation of the mitogen-activating protein (MAP) kinase pathway and its downstream target, the activating protien-1 (AP-1) complex, TGF-beta1 overexpression, enhanced protein kinase C activity, decreased cell proliferation, and impaired protein degradation rate, in part caused by decreased cathepsin activities. The pathogenic relevance of AGEs was further verified by in vivo experiments in euglycemic rats and mice by the parenteral administration of AGE albumin, leading in the glomeruli to TGF-beta1 overproduction, enhanced gene expression of ECM proteins, and morphological lesions similar to those of DN. Evidence for the pathogenic relevance of AGEs in DN also comes from experimental studies in which the formation and/or action of AGEs was modulated by aminoguanidine, OPB-9195, pyridoxamine, soluble RAGEs, serine protease trypsin, and antioxidants, resulting in improved cell and/or renal function.

  6. Sulforaphane suppresses vascular adhesion molecule-1 expression in TNF-α-stimulated mouse vascular smooth muscle cells: involvement of the MAPK, NF-κB and AP-1 signaling pathways.

    PubMed

    Kim, Ji-Yun; Park, Hye-Jin; Um, Sung Hee; Sohn, Eun-Hwa; Kim, Byung-Oh; Moon, Eun-Yi; Rhee, Dong-Kwon; Pyo, Suhkneung

    2012-01-01

    Atherosclerosis is a long-term inflammatory disease of the arterial wall. Increased expression of the cell adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) is associated with increased proliferation of vascular smooth muscle cells (VSMCs), leading to increased neointima or atherosclerotic lesion formation. Therefore, the functional inhibition of adhesion molecules could be a critical therapeutic target of inflammatory disease. In the present study, we investigate the effect of sulforaphane on the expression of VCAM-1 induced by TNF-α in cultured mouse vascular smooth muscle cell lines. Pretreatment of VSMCs for 2h with sulforaphane (1-5μg/ml) dose-dependently inhibited TNF-α-induced adhesion of THP-1 monocytic cells and protein expression of VCAM-1. Sulforaphane also suppressed TNF-α-induced production of intracellular reactive oxygen species (ROS) and activation of p38, ERK and JNK. Furthermore, sulforaphane inhibited NK-κB and AP-1 activation induced by TNF-α. Sulforaphane inhibited TNF-α-induced ΙκΒ kinase activation, subsequent degradation of ΙκΒα and nuclear translocation of p65 NF-κB and decreased c-Jun and c-Fos protein level. This study suggests that sulforaphane inhibits the adhesive capacity of VSMC and downregulates the TNF-α-mediated induction of VCAM-1 in VSMC by inhibiting the MAPK, NF-κB and AP-1 signaling pathways and intracellular ROS production. Thus, sulforaphane may have beneficial effects to suppress inflammation within the atherosclerotic lesion. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Quantal concept of T-cell activation: adhesion domains as immunological synapses

    NASA Astrophysics Data System (ADS)

    Sackmann, Erich

    2011-06-01

    Adhesion micro-domains (ADs) formed during encounters of lymphocytes with antigen-presenting cells (APC) mediate the genetic expression of quanta of cytokines interleukin-2 (IL-2). The IL-2-induced activation of IL-2 receptors promotes the stepwise progression of the T-cells through the cell cycle, hence their name, immunological synapses. The ADs form short-lived reaction centres controlling the recruitment of activators of the biochemical pathway (the kinases Lck and ZAP) while preventing the access of inhibitors (phosphatase CD45) through steric repulsion forces. CD45 acts as the generator of adhesion domains and, through its role as a spacer protein, also as the promoter of the reaction. In a second phase of T-cell-APC encounters, long-lived global reaction spaces (called supramolecular activation complexes (SMAC)) form by talin-mediated binding of the T-cell integrin (LFA-1) to the counter-receptor ICAM-1, resulting in the formation of ring-like tight adhesion zones (peripheral SMAC). The ADs move to the centre of the intercellular adhesion zone forming the central SMAC, which serve in the recycling of the AD. We propose that cell stimulation is triggered by integrating the effect evoked by the short-lived adhesion domains. Similar global reaction platforms are formed by killer cells to destruct APC. We present a testable mechanical model showing that global reaction spaces (SMAC or dome-like contacts between cytotoxic cells and APC) form by self-organization through delayed activation of the integrin-binding affinity and stabilization of the adhesion zones by F-actin recruitment. The mechanical stability and the polarization of the adhering T-cells are mediated by microtubule-actin cross-talk.

  8. Targeting Tumor Necrosis Factor-α with Adalimumab: Effects on Endothelial Activation and Monocyte Adhesion

    PubMed Central

    Oberoi, Raghav; Schuett, Jutta; Schuett, Harald; Koch, Ann-Kathrin; Luchtefeld, Maren

    2016-01-01

    Objective It is well known that atherosclerotic inflammatory vascular disease is critically driven by oxidized lipids and cytokines. In this regard, tumor necrosis factor (TNF)-α is known as a crucial mediator of early pro-atherosclerotic events. Epidemiologic data suggest that blockade of TNF-α has beneficial effects on vascular outcomes in patients with rheumatoid arthritis, however, detailed mechanistic studies are still lacking. This study aims to elucidate effects of TNF-α blockade by adalimumab–which is approved for several inflammatory disorders–on endothelial activation and monocyte adhesion under pro-atherosclerotic conditions. Methods and Results Phorbol myristate acetate (PMA) differentiated THP-1 macrophages were stimulated with oxidized low density lipoprotein and subsequent analysis of this conditioned media (oxLDL CM) revealed a strong release of TNF-α. The TNF-α rich supernatant led to activation of human umbilical vein endothelial cells (HUVEC) as shown by enhanced expression of major adhesion molecules, such as vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1) and E-selectin which was suppressed by the TNF-α inhibitor adalimumab. Accordingly, adalimumab effectively prevented THP-1 monocyte adhesion to endothelial cells under static as well as under flow conditions. Furthermore, adalimumab suppressed endothelial leakage as shown by Evan's blue diffusion across a confluent endothelial monolayer. Of note, after intraperitoneal injection we detected abundant deposition of fluorophore-labelled adalimumab in atherosclerotic plaques of hypercholesterolemic mice. Conclusion Our results show that adalimumab prevents major inflammatory effects of TNF-α on endothelial activation, endothelial monocyte adhesion, endothelial leakage and therefore extends the therapeutic options of adalimumab to limit vascular inflammation. PMID:27467817

  9. Vascular Cell Adhesion Molecule-1 Expression and Signaling During Disease: Regulation by Reactive Oxygen Species and Antioxidants

    PubMed Central

    Marchese, Michelle E.; Abdala-Valencia, Hiam

    2011-01-01

    Abstract The endothelium is immunoregulatory in that inhibiting the function of vascular adhesion molecules blocks leukocyte recruitment and thus tissue inflammation. The function of endothelial cells during leukocyte recruitment is regulated by reactive oxygen species (ROS) and antioxidants. In inflammatory sites and lymph nodes, the endothelium is stimulated to express adhesion molecules that mediate leukocyte binding. Upon leukocyte binding, these adhesion molecules activate endothelial cell signal transduction that then alters endothelial cell shape for the opening of passageways through which leukocytes can migrate. If the stimulation of this opening is blocked, inflammation is blocked. In this review, we focus on the endothelial cell adhesion molecule, vascular cell adhesion molecule-1 (VCAM-1). Expression of VCAM-1 is induced on endothelial cells during inflammatory diseases by several mediators, including ROS. Then, VCAM-1 on the endothelium functions as both a scaffold for leukocyte migration and a trigger of endothelial signaling through NADPH oxidase-generated ROS. These ROS induce signals for the opening of intercellular passageways through which leukocytes migrate. In several inflammatory diseases, inflammation is blocked by inhibition of leukocyte binding to VCAM-1 or by inhibition of VCAM-1 signal transduction. VCAM-1 signal transduction and VCAM-1-dependent inflammation are blocked by antioxidants. Thus, VCAM-1 signaling is a target for intervention by pharmacological agents and by antioxidants during inflammatory diseases. This review discusses ROS and antioxidant functions during activation of VCAM-1 expression and VCAM-1 signaling in inflammatory diseases. Antioxid. Redox Signal. 15, 1607–1638. PMID:21050132

  10. Highly sensitivity adhesion molecules detection in hereditary haemochromatosis patients reveals altered expression.

    PubMed

    Norris, S; White, M; Mankan, A K; Lawless, M W

    2010-04-01

    Several abnormalities in the immune status of patients with hereditary haemochromatosis (HH) have been reported, suggesting an imbalance in their immune function. This may include persistent production of, or exposure to, altered immune signalling contributing to the pathogenesis of this disorder. Adhesion molecules L-, E- and P-Selectin, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) are some of the major regulators of the immune processes and altered levels of these proteins have been found in pathological states including cardiovascular diseases, arthritis and liver cancer. The aim of this study was to assess L-, E- and P-Selectin, ICAM-1 and VCAM-1 expression in patients with HH and correlate these results with HFE mutation status and iron indexes. A total of 139 subjects were diagnosed with HH (C282Y homozygotes = 87, C282Y/H63D = 26 heterozygotes, H63D homozygotes = 26), 27 healthy control subjects with no HFE mutation (N/N), 18 normal subjects heterozygous for the H63D mutation served as age-sex-matched controls. We observed a significant decrease in L-selectin (P = 0.0002) and increased E-selectin and ICAM-1 (P = 0.0006 and P = 0.0059) expression in HH patients compared with healthy controls. This study observes for the first time that an altered adhesion molecules profile occurs in patients with HH that is associated with specific HFE genetic component for iron overload, suggesting that differential expression of adhesion molecules may play a role in the pathogenesis of HH.

  11. The low molecular weight Dextran 40 inhibits the adhesion of T lymphocytes to endothelial cells

    PubMed Central

    TERMEER, C C; WEISS, J M; SCHÖPF, E; VANSCHEIDT, W; SIMON, J C

    1998-01-01

    Dextrans are complex colloidal macromolecules widely used as haemorrheologic substances and anti-thrombotic agents. Here we describe a novel function of Dextran 40 by demonstrating an inhibition of T lymphocyte adhesion to endothelial cells (EC). We applied an established microassay in which constitutive and tumour necrosis factor-alpha (TNF-α)-induced binding of mouse T lymphoma cells (TK-1) to mouse endothelioma (eEND.2) cells is mediated by the interaction of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) on EC with their counter-receptors the LFA-1 heterodimer (CD11a/CD18) and VLA-4 on T cells. Dextran 40 in therapeutically achievable levels (2–32 mg/ml) reduced both constitutive and TNF-α-stimulated TK-1 adhesion to eEND.2. Selective preincubation of eEND.2 or TK-1 revealed that Dextran 40 acted exclusively on the T cells. To explore further the mechanisms by which Dextran 40 interfered with TK-1 adhesion, their LFA-1 and VLA-4 expression was analysed by FACS. The surface expression levels of neither receptor were affected by Dextran 40. However, confocal microscopy revealed that Dextran 40 interfered with the activation-dependent capping and clustering of LFA-1 and VLA-4 on the surface of TK-1. We conclude that Dextran 40 inhibits the capacity of TK-1 T cells to adhere to eEND.2 endothelial cells and thus may be useful for therapeutic intervention in diseases associated with enhanced T lymphocyte binding to microvascular endothelium. PMID:9844053

  12. Ephrin-A1/EphA4-mediated adhesion of monocytes to endothelial cells.

    PubMed

    Jellinghaus, Stefanie; Poitz, David M; Ende, Georg; Augstein, Antje; Weinert, Sönke; Stütz, Beryl; Braun-Dullaeus, Rüdiger C; Pasquale, Elena B; Strasser, Ruth H

    2013-10-01

    The Eph receptors represent the largest family of receptor tyrosine kinases. Both Eph receptors and their ephrin ligands are cell-surface proteins, and they typically mediate cell-to-cell communication by interacting at sites of intercellular contact. The major aim of the present study was to investigate the involvement of EphA4-ephrin-A1 interaction in monocyte adhesion to endothelial cells, as this process is a crucial step during the initiation and progression of the atherosclerotic plaque. Immunohistochemical analysis of human atherosclerotic plaques revealed expression of EphA4 receptor and ephrin-A1 ligand in major cell types within the plaque. Short-time stimulation of endothelial cells with the soluble ligand ephrin-A1 leads to a fourfold increase in adhesion of human monocytes to endothelial cells. In addition, ephrin-A1 further increases monocyte adhesion to already inflamed endothelial cells. EphrinA1 mediates its effect on monocyte adhesion via the activated receptor EphA4. This ephrinA1/EphA4 induced process involves the activation of the Rho signaling pathway and does not require active transcription. Rho activation downstream of EphA4 leads to increased polymerization of actin filaments in endothelial cells. This process was shown to be crucial for the proadhesive effect of ephrin-A1. The results of the present study show that ephrin-A1-induced EphA4 forward signaling promotes monocyte adhesion to endothelial cells via activation of RhoA and subsequent stress-fiber formation by a non-transcriptional mechanism. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. A single-cell analysis platform for electrochemiluminescent detection of platelets adhesion to endothelial cells based on Au@DL-ZnCQDs nanoprobes.

    PubMed

    Long, Dongping; Shang, Yunfei; Qiu, Youyi; Zhou, Bin; Yang, Peihui

    2018-04-15

    A novel single-cell analysis platform (SCA) was developed for the investigation of platelets adhesion to single human umbilical vein endothelial cell (HUVEC) via using the adhesion molecule (E-selectin) on the damaged HUVEC as the marker site, and integrating electrochemiluminescence (ECL) with the ultrasensitive Au@DL-ZnCQDs nanoprobes. The Au@DL-ZnCQDs nanocomposite, a kind of double layer zinc-coadsorbed carbon quantum dot (ZnCQDs) core-shell nanoprobe, was firstly constructed by using gold nanoparticles (AuNPs) as the core to load with ZnCQDs and then the citrate-modified silver nanoparticles (AgNPs) as the bridge to link AuNPs-ZnCQDs with ZnCQDs to form the core-shell with double layer ZnCQDs (DL-ZnCQDs) nanoprobe, revealed a 10-fold signal amplification. The H 2 O 2 -induced oxidative damage HUVECs were utilized as the cellular model on which anti-E-selectin functionalized nanoprobes specially recognized E-selectin, the SCA showed that the ECL signals decreased with platelets adhesion to single HUVEC. The proposed SCA could effectively and dynamically monitor the adhesion between single HUVEC and platelets in the absence and presence of collagen activation, moreover, be able to quantitatively detect the number of platelets adhesion to single HUVEC, and show a good analytical performance with linear range from 1 to 15 platelets. In contrast, the HUVEC was down-regulated the expression of adhesion molecules by treating with quercetin inhibitor, and the SCA also exhibited the feasibility for analysis of platelets adhesion to single HUVEC. Therefore, the single-cell analysis platform provided a novel and promising protocol for analysis of the single intercellular adhesion, and it will be beneficial to elucidate the pathogenesis of cardiovascular diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Anti-Inflammatory Effects of Pomegranate Peel Extract in THP-1 Cells Exposed to Particulate Matter PM10.

    PubMed

    Park, Soojin; Seok, Jin Kyung; Kwak, Jun Yup; Suh, Hwa-Jin; Kim, Young Mi; Boo, Yong Chool

    2016-01-01

    Epidemiological and experimental evidence support health risks associated with the exposure to airborne particulate matter with a diameter of <10 μM (PM10). PM10 stimulates the production of reactive oxygen species (ROS) and inflammatory mediators. Thus, we assumed that natural antioxidants might provide health benefits attenuating hazardous effects of PM10. In the present study, we examined the effects of pomegranate peel extract (PPE) on THP-1 monocytic cells exposed to PM10. PM10 induced cytotoxicity and the production of ROS. It also increased the expression and secretion of inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and monocyte chemoattractant protein-1 (MCP-1), and cell adhesion molecules, such as intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). PPE at 10-100 μg mL(-1) attenuated the production of ROS and the expression of TNF-α, IL-1β, MCP-1, and ICAM-1, but not VCAM-1, in THP-1 cells stimulated by PM10 (100 μg mL(-1)). PPE also attenuated the adhesion of PM10-stimulated THP-1 cells to EA.hy926 endothelial cells. PPE constituents, punicalagin and ellagic acid, attenuated PM10-induced monocyte adhesion to endothelial cells, and punicalagin was less cytotoxic compared to ellagic acid. The present study suggests that PPE and punicalagin may be useful in alleviating inflammatory reactions due to particulate matter.

  15. Diverse roles of guanine nucleotide exchange factors in regulating collective cell migration

    PubMed Central

    Tseng, Yun-Yu; Rabadán, M. Angeles; Krishna, Shefali; Hall, Alan

    2017-01-01

    Efficient collective migration depends on a balance between contractility and cytoskeletal rearrangements, adhesion, and mechanical cell–cell communication, all controlled by GTPases of the RHO family. By comprehensive screening of guanine nucleotide exchange factors (GEFs) in human bronchial epithelial cell monolayers, we identified GEFs that are required for collective migration at large, such as SOS1 and β-PIX, and RHOA GEFs that are implicated in intercellular communication. Down-regulation of the latter GEFs differentially enhanced front-to-back propagation of guidance cues through the monolayer and was mirrored by down-regulation of RHOA expression and myosin II activity. Phenotype-based clustering of knockdown behaviors identified RHOA-ARHGEF18 and ARHGEF3-ARHGEF28-ARHGEF11 clusters, indicating that the latter may signal through other RHO-family GTPases. Indeed, knockdown of RHOC produced an intermediate between the two phenotypes. We conclude that for effective collective migration, the RHOA-GEFs → RHOA/C → actomyosin pathways must be optimally tuned to compromise between generation of motility forces and restriction of intercellular communication. PMID:28512143

  16. A model for the kinetics of homotypic cellular aggregation under static conditions

    NASA Technical Reports Server (NTRS)

    Neelamegham, S.; Munn, L. L.; Zygourakis, K.; McIntire, L. V. (Principal Investigator)

    1997-01-01

    We present the formulation and testing of a mathematical model for the kinetics of homotypic cellular aggregation. The model considers cellular aggregation under no-flow conditions as a two-step process. Individual cells and cell aggregates 1) move on the tissue culture surface and 2) collide with other cells (or aggregates). These collisions lead to the formation of intercellular bonds. The aggregation kinetics are described by a system of coupled, nonlinear ordinary differential equations, and the collision frequency kernel is derived by extending Smoluchowski's colloidal flocculation theory to cell migration and aggregation on a two-dimensional surface. Our results indicate that aggregation rates strongly depend upon the motility of cells and cell aggregates, the frequency of cell-cell collisions, and the strength of intercellular bonds. Model predictions agree well with data from homotypic lymphocyte aggregation experiments using Jurkat cells activated by 33B6, an antibody to the beta 1 integrin. Since cell migration speeds and all the other model parameters can be independently measured, the aggregation model provides a quantitative methodology by which we can accurately evaluate the adhesivity and aggregation behavior of cells.

  17. Porcine Reproductive and Respiratory Syndrome Virus Utilizes Nanotubes for Intercellular Spread

    PubMed Central

    Guo, Rui; Katz, Benjamin B.; Tomich, John M.; Gallagher, Tom

    2016-01-01

    ABSTRACT Intercellular nanotube connections have been identified as an alternative pathway for cellular spreading of certain viruses. In cells infected with porcine reproductive and respiratory syndrome virus (PRRSV), nanotubes were observed connecting two distant cells with contiguous membranes, with the core infectious viral machinery (viral RNA, certain replicases, and certain structural proteins) present in/on the intercellular nanotubes. Live-cell movies tracked the intercellular transport of a recombinant PRRSV that expressed green fluorescent protein (GFP)-tagged nsp2. In MARC-145 cells expressing PRRSV receptors, GFP-nsp2 moved from one cell to another through nanotubes in the presence of virus-neutralizing antibodies. Intercellular transport of viral proteins did not require the PRRSV receptor as it was observed in receptor-negative HEK-293T cells after transfection with an infectious clone of GFP-PRRSV. In addition, GFP-nsp2 was detected in HEK-293T cells cocultured with recombinant PRRSV-infected MARC-145 cells. The intercellular nanotubes contained filamentous actin (F-actin) with myosin-associated motor proteins. The F-actin and myosin IIA were identified as coprecipitates with PRRSV nsp1β, nsp2, nsp2TF, nsp4, nsp7-nsp8, GP5, and N proteins. Drugs inhibiting actin polymerization or myosin IIA activation prevented nanotube formation and viral clusters in virus-infected cells. These data lead us to propose that PRRSV utilizes the host cell cytoskeletal machinery inside nanotubes for efficient cell-to-cell spread. This form of virus transport represents an alternative pathway for virus spread, which is resistant to the host humoral immune response. IMPORTANCE Extracellular virus particles transmit infection between organisms, but within infected hosts intercellular infection can be spread by additional mechanisms. In this study, we describe an alternative pathway for intercellular transmission of PRRSV in which the virus uses nanotube connections to transport infectious viral RNA, certain replicases, and certain structural proteins to neighboring cells. This process involves interaction of viral proteins with cytoskeletal proteins that form the nanotube connections. Intercellular viral spread through nanotubes allows the virus to escape the neutralizing antibody response and may contribute to the pathogenesis of viral infections. The development of strategies that interfere with this process could be critical in preventing the spread of viral infection. PMID:26984724

  18. Visualization of glucagon secretion from pancreatic α cells by bioluminescence video microscopy: Identification of secretion sites in the intercellular contact regions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yokawa, Satoru; School of Pharmacy, Aichi Gakuin University, Nagoya 464-8650; Suzuki, Takahiro

    We have firstly visualized glucagon secretion using a method of video-rate bioluminescence imaging. The fusion protein of proglucagon and Gaussia luciferase (PGCG-GLase) was used as a reporter to detect glucagon secretion and was efficiently expressed in mouse pancreatic α cells (αTC1.6) using a preferred human codon-optimized gene. In the culture medium of the cells expressing PGCG-GLase, luminescence activity determined with a luminometer was increased with low glucose stimulation and KCl-induced depolarization, as observed for glucagon secretion. From immunochemical analyses, PGCG-GLase stably expressed in clonal αTC1.6 cells was correctly processed and released by secretory granules. Luminescence signals of the secreted PGCG-GLase frommore » the stable cells were visualized by video-rate bioluminescence microscopy. The video images showed an increase in glucagon secretion from clustered cells in response to stimulation by KCl. The secretory events were observed frequently at the intercellular contact regions. Thus, the localization and frequency of glucagon secretion might be regulated by cell-cell adhesion. - Highlights: • The fused protein of proglucagon to Gaussia luciferase was used as a reporter. • The fusion protein was highly expressed using a preferred human-codon optimized gene. • Glucagon secretion stimulated by depolarization was determined by luminescence. • Glucagon secretion in α cells was visualized by bioluminescence imaging. • Glucagon secretion sites were localized in the intercellular contact regions.« less

  19. Circulating vascular cell adhesion molecule-1 in pre-eclampsia, gestational hypertension, and normal pregnancy: evidence of selective dysregulation of vascular cell adhesion molecule-1 homeostasis in pre-eclampsia.

    PubMed

    Higgins, J R; Papayianni, A; Brady, H R; Darling, M R; Walshe, J J

    1998-08-01

    Our purpose was to investigate circulating levels of vascular cell adhesion molecule-1 in the peripheral and uteroplacental circulations during normotensive and hypertensive pregnancies. This prospective observational study involved 2 patient groups. Group 1 consisted of 22 women with pre-eclampsia and 30 normotensive women followed up longitudinally through pregnancy and post partum. There were an additional 13 women with established gestational hypertension. Group 2 consisted of 20 women with established pre-eclampsia and 19 normotensive control subjects undergoing cesarean delivery. Plasma levels of vascular cell adhesion molecule-1 were measured in blood drawn from the antecubital vein (group 1) and from both the antecubital and uterine veins (group 2). Data were analyzed by analysis of variance. In group 1 vascular cell adhesion molecule-1 levels did not change significantly throughout normal pregnancy and post partum. Women with established pre-eclampsia had increased vascular cell adhesion molecule-1 levels compared with the normotensive pregnancy group (P = .01). Vascular cell adhesion molecule-1 levels were not elevated in women with established gestational hypertension. In group 2 significantly higher levels of vascular cell adhesion molecule-1 were detected in the uteroplacental (P < .0001) and peripheral (P < .0001) circulations of pre-eclamptic women by comparison with normotensive women. In the pre-eclamptic group there was a tendency toward higher vascular cell adhesion molecule-1 levels in the peripheral circulation than in the uteroplacental circulation (P = .06). In contrast to vascular cell adhesion molecule-1, circulating levels of E-selectin and intercellular adhesion molecule-1, other major leukocyte adhesion molecules expressed by the endothelium, were not different in pre-eclamptic and normotensive pregnancies. Established pre-eclampsia is characterized by selective dysregulation of vascular cell adhesion molecule-1 homeostasis. This event is not an early preclinical feature of pre-eclampsia, does not persist post partum, is not a feature of nonproteinuric gestational hypertension, and is not observed with other major leukocyte adhesion molecules. Induction of vascular cell adhesion molecule-1 expression in pre-eclampsia may contribute to leukocyte-mediated tissue injury in this condition or may reflect perturbation of other, previously unrecognized, functions of this molecule in pregnancy.

  20. A recessive mutation in the DSP gene linked to cardiomyopathy, skin fragility and hair defects impairs the binding of desmoplakin to epidermal keratins and the muscle-specific intermediate filament desmin.

    PubMed

    Favre, B; Begré, N; Borradori, L

    2018-06-07

    Desmoplakin (DSP) is a cytolinker of the plakin family. It mediates the connection of intermediate filaments (IFs) to desmosomes, intercellular adhesion junctions. The carboxyl (C)-terminal tail of DSP binds to IFs, while its amino-terminal part interacts with the armadillo proteins plakophilins and plakoglobin that in turn associate with the desmosomal cadherin desmogleins and desmocollins 1 . This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  1. Possible Involvement of Tight Junctions, Extracellular Matrix and Nuclear Receptors in Epithelial Differentiation

    PubMed Central

    Ichikawa-Tomikawa, Naoki; Sugimoto, Kotaro; Satohisa, Seiro; Nishiura, Keisuke; Chiba, Hideki

    2011-01-01

    Tight junctions are intercellular junctions localized at the most apical end of the lateral plasma membrane. They consist of four kinds of transmembrane proteins (occludin, claudins, junctional adhesion molecules, and tricellulin) and huge numbers of scaffolding proteins and contribute to the paracellular barrier and fence function. The mutation and deletion of these proteins impair the functions of tight junctions and cause various human diseases. In this paper, we provide an overview of recent studies on transmembrane proteins of tight junctions and highlight the functional significance of tight junctions, extracellular matrix, and nuclear receptors in epithelial differentiation. PMID:22162632

  2. Poly-N-acetylglucosamine mediates biofilm formation and detergent resistance in Aggregatibacter actinomycetemcomitans

    PubMed Central

    Izano, Era A.; Sadovskaya, Irina; Wang, Hailin; Vinogradov, Evgeny; Ragunath, Chandran; Ramasubbu, Narayanan; Jabbouri, Saïd; Perry, Malcolm B.; Kaplan, Jeffrey B.

    2008-01-01

    Clinical isolates of the periodontopathogen Aggregatibacter actinomycetemcomitans form matrix-encased biofilms on abiotic surfaces in vitro. A major component of the A. actinomycetemcomitans biofilm matrix is PGA, a hexosamine-containing polysaccharide that mediates intercellular adhesion. In this report we describe studies on the purification, structure, genetics and function of A. actinomycetemcomitans PGA. We found that PGA was very tightly attached to A. actinomycetemcomitans biofilm cells and could be efficiently separated from the cells only by phenol extraction. A. actinomycetemcomitans PGA copurified with LPS on a gel filtration column. 1H-NMR spectra of purified A. actinomycetemcomitans PGA were consistent with a structure containing a linear chain of N-acetyl-D-glucosamine residues in β(1,6) linkage. Genetic analyses indicated that all four genes of the pgaABCD locus were required for PGA production in A. actinomycetemcomitans. PGA mutant strains still formed biofilms in vitro. Unlike wild-type biofilms, however, PGA mutant biofilms were sensitive to detachment by DNase I and proteinase K. Treatment of A. actinomycetemcomitans biofilms with the PGA-hydrolyzing enzyme dispersin B made them 3 log units more sensitive to killing by the cationic detergent cetylpyridinium chloride. Our findings suggest that PGA, extracellular DNA and proteinaceous adhesins all contribute to the structural integrity of the A. actinomycetemcomitans biofilm matrix. PMID:17851029

  3. E-cadherin and cell adhesion: a role in architecture and function in the pancreatic islet.

    PubMed

    Rogers, Gareth J; Hodgkin, Matthew N; Squires, Paul E

    2007-01-01

    The efficient secretion of insulin from beta-cells requires extensive intra-islet communication. The cell surface adhesion protein epithelial (E)-cadherin (ECAD) establishes and maintains epithelial tissues such as the islets of Langerhans. In this study, the role of ECAD in regulating insulin secretion from pseudoislets was investigated. The effect of an immuno-neutralising ECAD on gross morphology, cytosolic calcium signalling, direct cell-to-cell communication and insulin secretion was assessed by fura-2 microfluorimetry, Lucifer Yellow dye injection and insulin ELISA in an insulin-secreting model system. Antibody blockade of ECAD reduces glucose-evoked changes in [Ca(2+)](i) and insulin secretion. Neutralisation of ECAD causes a breakdown in the glucose-stimulated synchronicity of calcium oscillations between discrete regions within the pseudoislet, and the transfer of dye from an individual cell within a cell cluster is attenuated in the absence of ECAD ligation, demonstrating that gap junction communication is disrupted. The functional consequence of neutralising ECAD is a significant reduction in insulin secretion. Cell adhesion via ECAD has distinct roles in the regulation of intercellular communication between beta-cells within islets, with potential repercussions for insulin secretion.

  4. Branched actin networks push against each other at adherens junctions to maintain cell-cell adhesion.

    PubMed

    Efimova, Nadia; Svitkina, Tatyana M

    2018-05-07

    Adherens junctions (AJs) are mechanosensitive cadherin-based intercellular adhesions that interact with the actin cytoskeleton and carry most of the mechanical load at cell-cell junctions. Both Arp2/3 complex-dependent actin polymerization generating pushing force and nonmuscle myosin II (NMII)-dependent contraction producing pulling force are necessary for AJ morphogenesis. Which actin system directly interacts with AJs is unknown. Using platinum replica electron microscopy of endothelial cells, we show that vascular endothelial (VE)-cadherin colocalizes with Arp2/3 complex-positive actin networks at different AJ types and is positioned at the interface between two oppositely oriented branched networks from adjacent cells. In contrast, actin-NMII bundles are located more distally from the VE-cadherin-rich zone. After Arp2/3 complex inhibition, linear AJs split, leaving gaps between cells with detergent-insoluble VE-cadherin transiently associated with the gap edges. After NMII inhibition, VE-cadherin is lost from gap edges. We propose that the actin cytoskeleton at AJs acts as a dynamic push-pull system, wherein pushing forces maintain extracellular VE-cadherin transinteraction and pulling forces stabilize intracellular adhesion complexes. © 2018 Efimova and Svitkina.

  5. Intercellular diffusion of a fluorescent sucrose analog via the septal junctions in a filamentous cyanobacterium.

    PubMed

    Nürnberg, Dennis J; Mariscal, Vicente; Bornikoel, Jan; Nieves-Morión, Mercedes; Krauß, Norbert; Herrero, Antonia; Maldener, Iris; Flores, Enrique; Mullineaux, Conrad W

    2015-03-17

    Many filamentous cyanobacteria produce specialized nitrogen-fixing cells called heterocysts, which are located at semiregular intervals along the filament with about 10 to 20 photosynthetic vegetative cells in between. Nitrogen fixation in these complex multicellular bacteria depends on metabolite exchange between the two cell types, with the heterocysts supplying combined-nitrogen compounds but dependent on the vegetative cells for photosynthetically produced carbon compounds. Here, we used a fluorescent tracer to probe intercellular metabolite exchange in the filamentous heterocyst-forming cyanobacterium Anabaena sp. strain PCC 7120. We show that esculin, a fluorescent sucrose analog, is incorporated by a sucrose import system into the cytoplasm of Anabaena cells. The cytoplasmic esculin is rapidly and reversibly exchanged across vegetative-vegetative and vegetative-heterocyst cell junctions. Our measurements reveal the kinetics of esculin exchange and also show that intercellular metabolic communication is lost in a significant fraction of older heterocysts. SepJ, FraC, and FraD are proteins located at the intercellular septa and are suggested to form structures analogous to gap junctions. We show that a ΔsepJ ΔfraC ΔfraD triple mutant shows an altered septum structure with thinner septa but a denser peptidoglycan layer. Intercellular diffusion of esculin and fluorescein derivatives is impaired in this mutant, which also shows a greatly reduced frequency of nanopores in the intercellular septal cross walls. These findings suggest that FraC, FraD, and SepJ are important for the formation of junctional structures that constitute the major pathway for feeding heterocysts with sucrose. Anabaena and its relatives are filamentous cyanobacteria that exhibit a sophisticated form of prokaryotic multicellularity, with the formation of differentiated cell types, including normal photosynthetic cells and specialized nitrogen-fixing cells called heterocysts. The question of how heterocysts communicate and exchange metabolites with other cells in the filament is key to understanding this form of bacterial multicellularity. Here we provide the first information on the intercellular exchange of a physiologically important molecule, sucrose. We show that a fluorescent sucrose analog can be imported into the Anabaena cytoplasm by a sucrose import system. Once in the cytoplasm, it is rapidly and reversibly exchanged among all of the cells in the filament by diffusion across the septal junctions. Photosynthetically produced sucrose likely follows the same route from cytoplasm to cytoplasm. We identify some of the septal proteins involved in sucrose exchange, and our results indicate that these proteins form structures functionally analogous to metazoan gap junctions. Copyright © 2015 Nürnberg et al.

  6. Endothelial NOS is required for SDF-1alpha/CXCR4-mediated peripheral endothelial adhesion of c-kit+ bone marrow stem cells.

    PubMed

    Kaminski, Alexander; Ma, Nan; Donndorf, Peter; Lindenblatt, Nicole; Feldmeier, Gregor; Ong, Lee-Lee; Furlani, Dario; Skrabal, Christian A; Liebold, Andreas; Vollmar, Brigitte; Steinhoff, Gustav

    2008-01-01

    In the era of intravascular approaches for regenerative cell therapy, the underlying mechanisms of stem cell migration to non-marrow tissue have not been clarified. We hypothesized that next to a local inflammatory response implying adhesion molecule expression, endothelial nitric oxide synthase (eNOS)-dependent signaling is required for stromal- cell-derived factor-1 alpha (SDF-1alpha)-induced adhesion of c-kit+ cells to the vascular endothelium. SDF-1alpha/tumor necrosis factor-alpha (TNF-alpha)-induced c-kit+-cell shape change and migration capacity was studied in vitro using immunohistochemistry and Boyden chamber assays. In vivo interaction of c-kit+ cells from bone marrow with the endothelium in response to SDF-1alpha/TNF-alpha stimulation was visualized in the cremaster muscle microcirculation of wild-type (WT) and eNOS (-/-) mice using intravital fluorescence microscopy. In addition, NOS activity was inhibited with N-nitro-L-arginine-methylester-hydrochloride in WT mice. To reveal c-kit+-specific adhesion behavior, endogenous leukocytes (EL) and c-kit+ cells from peripheral blood served as control. Moreover, intercellular adhesion molecule-1 (ICAM-1) and CXCR4 were blocked systemically to determine their role in inflammation-related c-kit+-cell adhesion. In vitro, SDF-1alpha enhanced c-kit+-cell migration. In vivo, SDF-1alpha alone triggered endothelial rolling-not firm adherence-of c-kit+ cells in WT mice. While TNF-alpha alone had little effect on adhesion of c-kit+ cells, it induced maximum endothelial EL adherence. However, after combined treatment with SDF-1alpha+TNF-alpha, endothelial adhesion of c-kit+ cells increased independent of their origin, while EL adhesion was not further incremented. Systemic treatment with anti-ICAM-1 and anti-CXCR4-monoclonal antibody completely abolished endothelial c-kit+-cell adhesion. In N-nitro-L-arginine-methylester-hydrochloride-treated WT mice as well as in eNOS (-/-) mice, firm endothelial adhesion of c-kit+ cells was entirely abrogated, while EL adhesion was significantly increased. The chemokine SDF-1alpha mediates firm adhesion c-kit+ cells only in the presence of TNF-alpha stimulation via an ICAM-1- and CXCR4-dependent mechanism. The presence of eNOS appears to be a crucial and specific factor for firm c-kit+-cell adhesion to the vascular endothelium.

  7. Interplay between Rolling and Firm Adhesion Elucidated with a Cell-Free System Engineered with Two Distinct Receptor-Ligand Pairs

    PubMed Central

    Eniola, A. Omolola; Willcox, P. Jeanene; Hammer, Daniel A.

    2003-01-01

    The firm arrest of leukocytes to the endothelium during inflammation is known to be mediated by endothelial intercellular adhesion molecules (ICAMs) binding to activated integrins displayed on leukocyte surface. Selectin-ligand interactions, which mediate rolling, are believed to be important for facilitating firm adhesion, either by activating integrins or by facilitating the transition to firm adhesion by making it easier for integrins to bind. Although leukocytes employ two distinct adhesion molecules that mediate different states of adhesion, the fundamental biophysical mechanisms by which two pairs of adhesion molecules facilitate cell adhesion is not well understood. In this work, we attempt to understand the interaction between two molecular systems using a cell-free system in which polystyrene microspheres functionalized with the selectin ligand, sialyl LewisX (sLeX), and an antibody against ICAM-1, aICAM-1, are perfused over P-selectin/ICAM-1 coated surfaces in a parallel plate flow chamber. Separately, sLeX/P-selectin interactions support rolling and aICAM-1/ICAM-1 interactions mediate firm adhesion. Our results show that sLeX/aICAM-1 microspheres will firmly adhere to P-selectin/ICAM-1 coated surfaces, and that the extent of firm adhesion of microspheres is dependent on wall shear stress within the flow chamber, sLeX/aICAM-1 microsphere site density, and P-selectin/ICAM-1 surface density ratio. We show that P-selectin's interaction with sLeX mechanistically facilitates firm adhesion mediated by antibody binding to ICAM-1: the extent of firm adhesion for the same concentration of aICAM-1/ICAM-1 interaction is greater when sLeX/P-selectin interactions are present. aICAM-1/ICAM-1 interactions also stabilize rolling by increasing pause times and decreasing average rolling velocities. Although aICAM-1 is a surrogate for β2-integrin, the kinetics of association between aICAM-1 and ICAM-1 is within a factor of 1.5 of activated integrin binding ICAM-1, suggesting the findings from this model system may be insightful to the mechanism of leukocyte firm adhesion. In particular, these experimental results show how two molecule systems can interact to produce an effect not achievable by either system alone, a fundamental mechanism that may pervade leukocyte adhesion biology. PMID:14507735

  8. Cigarette smoke increases BLT2 receptor functions in bronchial epithelial cells: in vitro and ex vivo evidence

    PubMed Central

    Pace, Elisabetta; Ferraro, Maria; Vincenzo, Serena Di; Bruno, Andreina; Giarratano, Antonino; Scafidi, Valeria; Lipari, Luana; Benedetto, Denise Valentina Di; Sciarrino, Serafina; Gjomarkaj, Mark

    2013-01-01

    Leukotriene B4 (LTB4) is a neutrophil chemotactic molecule with important involvement in the inflammatory responses of chronic obstructive pulmonary disease (COPD). Airway epithelium is emerging as a regulator of innate immune responses to a variety of insults including cigarette smoke, the major risk factor for COPD. In this study we have explored whether cigarette smoke extracts (CSE) or soluble mediators present in distal lung fluid samples (mini-bronchoalveolar lavages) from smokers alter the expression of the LTB4 receptor 2 (BLT2) and peroxisome proliferator-activated receptor-α (PPAR-α) in bronchial epithelial cells. We also evaluated the effects of CSE on the expression of intercellular adhesion molecule 1 (ICAM-1) and on the binding of signal transducer and activator of transcription 1 (STAT-1) to ICAM-1 promoter as well as the adhesiveness of neutrophils to bronchial epithelial cells. CSE and mini-bronchoalveolar lavages from smokers increased BLT2 and ICAM-1 expression as well as the adhesiveness of neutrophils to bronchial epithelial cells and decreased PPAR-α expression. CSE induced the activation of STAT-1 and its binding to ICAM-1 promoter. These findings suggest that, in bronchial epithelial cells, CSE promote a prevalent induction of pro-inflammatory BLT2 receptors and activate mechanisms leading to increased neutrophil adhesion, a mechanism that contributes to airway neutrophilia and to tissue damage. PMID:23347335

  9. Anti-inflammatory and anti-angiogenic effects of flavonoids isolated from Lycium barbarum Linnaeus on human umbilical vein endothelial cells.

    PubMed

    Wu, Wen-Bin; Hung, Dian-Kun; Chang, Fung-Wei; Ong, Eng-Thaim; Chen, Bing-Huei

    2012-10-01

    Anti-inflammatory and anti-angiogenic effects of flavonoids isolated from Lycium barbarum fruits, a traditional Chinese medicine, on human umbilical vein endothelial cells (HUVECs) were investigated. Initially, flavonoids were extracted with 80% ethanol and separated using a Cosmosil 140 C18-OPN column, with the acidic fraction eluted with deionized water being composed of chlorogenic acid, caffeoyl quinic acid, caffeic acid and p-coumaric acid and the neutral fraction eluted with methanol composed of quercetin-diglycoside, rutin and kaempferol-O-rutinoside. Flavonoid extract was effective in inhibiting expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule (VCAM-1) induced by TNF-α in HUVECs. The RT-PCR analysis indicated that ICAM-1 mRNA induced by TNF-α was inhibited by flavonoid extract. The flavonoid extract attenuated TNF-α-induced IκB phosphorylation as well as NF-κB, p65 and p50 translocation from cytosol to nucleus, through inhibition on TNF-α- and H(2)O(2)-induced intracellular reactive oxygen species (ROS) production. For the anti-angiogenic study, the flavonoid extract inhibited vascular endothelial growth factor (VEGF)-induced cell proliferation and migration in HUVECs, as well as angiogenesis. However, the flavonoid extract did not inhibit VEGF signaling. Surprisingly, HUVECs adhesion to the extracellular matrix was compromised and adhesion-induced signaling was retarded by the flavonoid extract.

  10. I-domain of lymphocyte function-associated antigen-1 mediates rolling of polystyrene particles on ICAM-1 under flow.

    PubMed

    Eniola, A Omolola; Krasik, Ellen F; Smith, Lee A; Song, Gang; Hammer, Daniel A

    2005-11-01

    In their active state, beta(2)-integrins, such as LFA-1, mediate the firm arrest of leukocytes by binding intercellular adhesion molecules (ICAMs) expressed on endothelium. Although the primary function of LFA-1 is assumed to be the ability to mediate firm adhesion, recent work has shown that LFA-1 can contribute to cell tethering and rolling under hydrodynamic flow, a role previously largely attributed to the selectins. The inserted (I) domain of LFA-1 has recently been crystallized in the wild-type (wt) and locked-open conformations and has been shown to, respectively, support rolling and firm adhesion under flow when expressed in alpha(L)beta(2) heterodimers or as isolated domains on cells. Here, we report results from cell-free adhesion assays where wt I-domain-coated polystyrene particles were allowed to interact with ICAM-1-coated surfaces in shear flow. We show that wt I-domain can independently mediate the capture of particles from flow and support their rolling on ICAM-1 surfaces in a manner similar to how carbohydrate-selectin interactions mediate rolling. Adhesion is specific and blocked by appropriate antibodies. We also show that the rolling velocity of I-domain-coated particles depends on the wall shear stress in flow chamber, I-domain site density on microsphere surfaces, and ICAM-1 site density on substrate surfaces. Furthermore, we show that rolling is less sensitive to wall shear stress and ICAM-1 substrate density at high density of I-domain on the microsphere surface. Computer simulations using adhesive dynamics can recreate bead rolling dynamics and show that the mechanochemical properties of ICAM-1-I-domain interactions are similar to those of carbohydrate-selectin interactions. Understanding the biophysics of adhesion mediated by the I-domain of LFA-1 can elucidate the complex roles this integrin plays in leukocyte adhesion in inflammation.

  11. Inhibition of endothelial receptor expression and of T-cell ligand activity by mycophenolate mofetil.

    PubMed

    Blaheta, R A; Leckel, K; Wittig, B; Zenker, D; Oppermann, E; Harder, S; Scholz, M; Weber, S; Schuldes, H; Encke, A; Markus, B H

    1998-12-01

    The novel immunosuppressive drug mycophenolate mofetil (CellCept, MMF) blocks DNA-synthesis by the inhibition of the enzyme inosine monophosphate dehydrogenase (IMDH). IMDH is also involved in the synthesis of adhesion receptors which are known to play an important role in the regulation of cell-cell contacts. Therefore, application of MMF might lead to a reduction of cellular infiltrates in the course of transplant rejection. To evaluate the therapeutic value of MMF, we investigated to what extent MMF blocks T-lymphocyte infiltration in vitro with regard to (a) adhesion to endothelial cells, (b) horizontal migration along these cells and (c) penetration through the endothelial cells. The results demonstrated a strong inhibition of both CD4+ and CD8+ T-cell adhesion and penetration by MMF. The ID50 value for CD4+ T-cell adhesion was calculated to be 0.03 microM and the ID50 value for CD4+ T-cell penetration 1.21 microM. MMF did not significantly influence the horizontal migration of T-lymphocytes along the human vascular endothelial cell (HUVEC) borders. FACS-analysis revealed a diminished E-selectin and P-selectin expression on endothelial cell membranes in the presence of MMF. Although MMF did not interfere with the synthesis of T-cell adhesion ligands, the binding activity of lymphocytic leucocyte function associated antigen 1 (LFA-1), very late antigen 4 (VLA-4) and PSGL-1 (P-selectin glycoprotein ligand 1) to immobilized intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1) and P-selectin was impaired. Moreover, MMF prevented VLA-4 and PSGL-1 receptor accumulation on the membranes of T-cell pseudopodia. It can be concluded that MMF possesses potent infiltration blocking properties. MMF evoked down-regulation of specific endothelial membrane molecules and the loss of protein localization in the lymphocyte protrusions might be predominantly responsible for the observed blockade of cell adhesion and penetration.

  12. Thalidomide inhibits inflammatory and angiogenic activation of human intestinal microvascular endothelial cells (HIMEC).

    PubMed

    Rafiee, Parvaneh; Stein, Daniel J; Nelson, Victoria M; Otterson, Mary F; Shaker, Reza; Binion, David G

    2010-02-01

    The glutamic acid derivative thalidomide is a transcriptional inhibitor of TNF-alpha but is also known to affect human blood vessels, which may underlie its teratogenicity. Thalidomide has been used in the treatment of refractory Crohn's disease (CD), but the therapeutic mechanism is not defined. We examined the effect of thalidomide on primary cultures of human intestinal microvascular endothelial cells (HIMEC), the relevant endothelial cell population in inflammatory bowel disease (IBD), to determine its effect on endothelial activation, leukocyte interaction, and VEGF-induced angiogenesis. HIMEC cultures were pretreated with thalidomide before activation with either TNF-alpha/LPS or VEGF. A low-shear-stress flow adhesion assay with either U-937 or whole blood was used to assess HIMEC activation following TNF-alpha/LPS, and a Wright's stain identified adherent leukocytes. Expression of cell adhesion molecules (E-selectin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1) was assessed using radioimmunoassay. Effects of thalidomide on NF-kappaB activation, cyclooxygenase (COX)-2, and inducible nitric oxide synthase (iNOS) expression in TNF-alpha/LPS-activated HIMEC were determined by RT-PCR and Western blotting. Thalidomide blocked adhesion of both U-937 and whole blood leukocytes by 50% in HIMEC, inhibiting binding of all classes of leukocytes. Thalidomide also blocked NF-kappaB and cell adhesion molecule expression in HIMEC. In marked contrast, thalidomide did not affect either iNOS or COX-2 expression, two key molecules that play a role in the downregulation of HIMEC activation. VEGF-induced HIMEC transmigration, growth, proliferation, tube formation, and Akt phosphorylation were significantly inhibited by thalidomide. In summary, thalidomide exerted a potent effect on HIMEC growth and activation, suggesting that it may also function via an endothelial mechanism in the treatment of CD.

  13. Thalidomide inhibits inflammatory and angiogenic activation of human intestinal microvascular endothelial cells (HIMEC)

    PubMed Central

    Stein, Daniel J.; Nelson, Victoria M.; Otterson, Mary F.; Shaker, Reza; Binion, David G.

    2010-01-01

    The glutamic acid derivative thalidomide is a transcriptional inhibitor of TNF-α but is also known to affect human blood vessels, which may underlie its teratogenicity. Thalidomide has been used in the treatment of refractory Crohn's disease (CD), but the therapeutic mechanism is not defined. We examined the effect of thalidomide on primary cultures of human intestinal microvascular endothelial cells (HIMEC), the relevant endothelial cell population in inflammatory bowel disease (IBD), to determine its effect on endothelial activation, leukocyte interaction, and VEGF-induced angiogenesis. HIMEC cultures were pretreated with thalidomide before activation with either TNF-α/LPS or VEGF. A low-shear-stress flow adhesion assay with either U-937 or whole blood was used to assess HIMEC activation following TNF-α/LPS, and a Wright's stain identified adherent leukocytes. Expression of cell adhesion molecules (E-selectin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1) was assessed using radioimmunoassay. Effects of thalidomide on NF-κB activation, cyclooxygenase (COX)-2, and inducible nitric oxide synthase (iNOS) expression in TNF-α/LPS-activated HIMEC were determined by RT-PCR and Western blotting. Thalidomide blocked adhesion of both U-937 and whole blood leukocytes by 50% in HIMEC, inhibiting binding of all classes of leukocytes. Thalidomide also blocked NF-κB and cell adhesion molecule expression in HIMEC. In marked contrast, thalidomide did not affect either iNOS or COX-2 expression, two key molecules that play a role in the downregulation of HIMEC activation. VEGF-induced HIMEC transmigration, growth, proliferation, tube formation, and Akt phosphorylation were significantly inhibited by thalidomide. In summary, thalidomide exerted a potent effect on HIMEC growth and activation, suggesting that it may also function via an endothelial mechanism in the treatment of CD. PMID:19926820

  14. Alteration of pancreatic carcinoma and promyeloblastic cell adhesion in liver microvasculature by co-culture of hepatocytes, hepatic stellate cells and endothelial cells in a physiologically-relevant model.

    PubMed

    Danoy, Mathieu; Shinohara, Marie; Rizki-Safitri, Astia; Collard, Dominique; Senez, Vincent; Sakai, Yasuyuki

    2017-04-18

    In vitro models of the liver microvasculature, especially with respect to cancer cell extravasation, should include not only endothelial and cancer cells but also surrounding cells to mimic the physiological situation. To this end, in the present study, we established a physiologically-relevant hierarchical co-culture model by stacking layers of primary rat hepatocytes (Hep), hepatic stellate cells embedded in collagen gel (LX-2) and endothelial cells (HUVECs) on a specially designed oxygen-permeable polydimethylsiloxane PDMS bottom plate. The model was used to investigate the role and contribution of each of the three cell types in pancreatic cancer and promyeloblast cell adhesion. In particular, we showed an increase in albumin production by the primary hepatocytes and in the consumption of the produced vascular endothelial growth factors (VEGFs). Furthermore, in co-culture, the HUVECs exhibited a mature vascular endothelial and non-inflamed phenotype, as evidenced by Stabilin-1, lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1), intercellular adhesion molecule (ICAM-1), and vascular adhesion protein-1 (VAP-1) expression. The HUVECs were also successfully activated with an inflammatory cytokine and their ICAM-1 response was found to be higher in monoculture compared to co-culture. Additionally, the adhesion of MiaPaCa-2 pancreatic cancer cells and HL60 promyeloblasts was tested in both cases (i.e.: activation or not by an inflammatory cytokine). It has been found that their adhesion was always reduced in the co-culture model. These results highlight the importance of integrating hepatic stellate cells in the design of biomimetic models of the hepatic endothelial barrier.

  15. Cobra CRISP functions as an inflammatory modulator via a novel Zn2+- and heparan sulfate-dependent transcriptional regulation of endothelial cell adhesion molecules.

    PubMed

    Wang, Yu-Ling; Kuo, Je-Hung; Lee, Shao-Chen; Liu, Jai-Shin; Hsieh, Yin-Cheng; Shih, Yu-Tsung; Chen, Chun-Jung; Chiu, Jeng-Jiann; Wu, Wen-Guey

    2010-11-26

    Cysteine-rich secretory proteins (CRISPs) have been identified as a toxin family in most animal venoms with biological functions mainly associated with the ion channel activity of cysteine-rich domain (CRD). CRISPs also bind to Zn(2+) at their N-terminal pathogenesis-related (PR-1) domain, but their function remains unknown. Interestingly, similar the Zn(2+)-binding site exists in all CRISP family, including those identified in a wide range of organisms. Here, we report that the CRISP from Naja atra (natrin) could induce expression of vascular endothelial cell adhesion molecules, i.e. intercellular adhesion molecule-1, vascular adhesion molecule-1, and E-selectin, to promote monocytic cell adhesion in a heparan sulfate (HS)- and Zn(2+)-dependent manner. Using specific inhibitors and small interfering RNAs, the activation mechanisms are shown to involve both mitogen-activated protein kinases and nuclear factor-κB. Biophysical characterization of natrin by using fluorescence, circular dichroism, and x-ray crystallographic methods further reveals the presence of two Zn(2+)-binding sites for natrin. The strong binding site is located near the putative Ser-His-Glu catalytic triad of the N-terminal domain. The weak binding site remains to be characterized, but it may modulate HS binding by enhancing its interaction with long chain HS. Our results strongly suggest that natrin may serve as an inflammatory modulator that could perturb the wound-healing process of the bitten victim by regulating adhesion molecule expression in endothelial cells. Our finding uncovers a new aspect of the biological role of CRISP family in immune response and is expected to facilitate future development of new therapeutic strategy for the envenomed victims.

  16. Effect of treatment with the antioxidant alpha-lipoic (thioctic) acid on heart and kidney microvasculature in spontaneously hypertensive rats.

    PubMed

    Tayebati, Seyed Khosrow; Tomassoni, Daniele; Di Cesare Mannelli, Lorenzo; Amenta, Francesco

    2016-01-01

    Endothelial cells represent an important vascular site of signaling and development of damage during ischemia, inflammation and other pathological conditions. Excessive reactive oxygen species production causes pathological activation of endothelium including exposure of cell to adhesion molecules. Intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and platelet-endothelial cell adhesion molecule-1 (PECAM-1) are members of the immunoglobulin super-family which are present on the surface of endothelial cells. These molecules represent important markers of endothelial inflammation. The present study was designed to investigate, with immunochemical and immunohistochemical techniques, the effect of treatment with (+/-)-alpha lipoic (thioctic) acid and its enantiomers on heart and kidney endothelium in spontaneously hypertensive rats (SHR). Arterial hypertension is accompanied by an increased oxidative stress status in the heart characterized by thiobarbituric acid reactive substances (TBARS) and nucleic acid oxidation increase. The higher oxidative stress also modifies adhesion molecules expression. In the heart VCAM-1, which was higher than ICAM-1 and PECAM-1, was increased in SHR. ICAM-1, VCAM-1 and PECAM-1 expression was significantly greater in the renal endothelium of SHR. (+/-)-Alpha lipoic acid and (+)-alpha lipoic acid treatment significantly decreased TBARS levels, the nucleic acid oxidation and prevented adhesion molecules expression in cardiac and renal vascular endothelium. These data suggest that endothelial molecules may be used for studying the mechanisms of vascular injury on target organs of hypertension. The effects observed after treatment with (+)-alpha lipoic acid could open new perspectives for countering heart and kidney microvascular injury which represent a common feature in hypertensive end-organs damage.

  17. Glutathione regulation of redox-sensitive signals in tumor necrosis factor-{alpha}-induced vascular endothelial dysfunction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsou, T.-C.; Yeh, S.C.; Tsai, F.-Y.

    2007-06-01

    We investigated the regulatory role of glutathione in tumor necrosis factor-alpha (TNF-{alpha})-induced vascular endothelial dysfunction as evaluated by using vascular endothelial adhesion molecule expression and monocyte-endothelial monolayer binding. Since TNF-{alpha} induces various biological effects on vascular cells, TNF-{alpha} dosage could be a determinant factor directing vascular cells into different biological fates. Based on the adhesion molecule expression patterns responding to different TNF-{alpha} concentrations, we adopted the lower TNF-{alpha} (0.2 ng/ml) to rule out the possible involvement of other TNF-{alpha}-induced biological effects. Inhibition of glutathione synthesis by L-buthionine-(S,R)-sulfoximine (BSO) resulted in down-regulations of the TNF-{alpha}-induced adhesion molecule expression and monocyte-endothelial monolayermore » binding. BSO attenuated the TNF-{alpha}-induced nuclear factor-kappaB (NF-{kappa}B) activation, however, with no detectable effect on AP-1 and its related mitogen-activated protein kinases (MAPKs). Deletion of an AP-1 binding site in intercellular adhesion molecule-1 (ICAM-1) promoter totally abolished its constitutive promoter activity and its responsiveness to TNF-{alpha}. Inhibition of ERK, JNK, or NF-{kappa}B attenuates TNF-{alpha}-induced ICAM-1 promoter activation and monocyte-endothelial monolayer binding. Our study indicates that TNF-{alpha} induces adhesion molecule expression and monocyte-endothelial monolayer binding mainly via activation of NF-{kappa}B in a glutathione-sensitive manner. We also demonstrated that intracellular glutathione does not modulate the activation of MAPKs and/or their downstream AP-1 induced by lower TNF-{alpha}. Although AP-1 activation by the lower TNF-{alpha} was not detected in our systems, we could not rule out the possible involvement of transiently activated MAPKs/AP-1 in the regulation of TNF-{alpha}-induced adhesion molecule expression.« less

  18. Increased ICAM-1 Expression in Transformed Human Oral Epithelial Cells: Molecular Mechanism and Functional Role in Peripheral Blood Mononuclear Cell Adhesion and Lymphokine-Activated-Killer Cell Cytotoxicity

    PubMed Central

    Huang, George T.-J.; Zhang, Xinli; Park, No-Hee

    2012-01-01

    The intercellular adhesion molecule-1 (ICAM-1, CD54) serves as a counter-receptor for the β2-integrins, LFA-1 and Mac-1, which are expressed on leukocytes. Although expression of ICAM-1 on tumor cells has a role in tumor progression and development, information on ICAM-1 expression and its role in oral cancer has not been established. Normal human oral keratinocytes (NHOK), human papilloma virus (HPV)-immortalized human oral keratinocyte lines (HOK-16B, HOK-18A, and HOK-18C), and six human oral neoplastic cell lines (HOK-16B-BaP-T1, SCC-4, SCC-9, HEp-2, Tu-177 and 1483) were used to study ICAM-1 expression and its functional role in vitro. Our results demonstrated that NHOK express negligible levels of ICAM-1, whereas immortalized human oral keratinocytes and cancer cells express significantly higher levels of ICAM-1, except for HOK-16B-BaP-T1 and HEp-2. Altered mRNA half-lives did not fully account for the increased accumulation of ICAM-1 mRNA. Adhesion of peripheral blood mononuclear cells (PBMC) to epithelial cells correlated with cell surface ICAM-1 expression levels. This adhesion was inhibited by antibodies specific for either ICAM-1 or LFA-1/Mac-1, suggesting a role for these molecules in adhesion. In contrast, lymphokine-activated-killer (LAK) cell cytotoxic killing of epithelial cells did not correlate with ICAM-1 levels or with adhesion. Nonetheless, within each cell line, blocking of ICAM-1 or LFA-1/Mac-1 reduced LAK cells killing, suggesting that ICAM-1 is involved in mediating this killing. PMID:10938387

  19. Screening for genes and subnetworks associated with pancreatic cancer based on the gene expression profile.

    PubMed

    Long, Jin; Liu, Zhe; Wu, Xingda; Xu, Yuanhong; Ge, Chunlin

    2016-05-01

    The present study aimed to screen for potential genes and subnetworks associated with pancreatic cancer (PC) using the gene expression profile. The expression profile GSE 16515 was downloaded from the Gene Expression Omnibus database, which included 36 PC tissue samples and 16 normal samples. Limma package in R language was used to screen differentially expressed genes (DEGs), which were grouped as up‑ and downregulated genes. Then, PFSNet was applied to perform subnetwork analysis for all the DEGs. Moreover, Gene Ontology (GO) and REACTOME pathway enrichment analysis of up‑ and downregulated genes was performed, followed by protein‑protein interaction (PPI) network construction using Search Tool for the Retrieval of Interacting Genes Search Tool for the Retrieval of Interacting Genes. In total, 1,989 DEGs including 1,461 up‑ and 528 downregulated genes were screened out. Subnetworks including pancreatic cancer in PC tissue samples and intercellular adhesion in normal samples were identified, respectively. A total of 8 significant REACTOME pathways for upregulated DEGs, such as hemostasis and cell cycle, mitotic were identified. Moreover, 4 significant REACTOME pathways for downregulated DEGs, including regulation of β‑cell development and transmembrane transport of small molecules were screened out. Additionally, DEGs with high connectivity degrees, such as CCNA2 (cyclin A2) and PBK (PDZ binding kinase), of the module in the protein‑protein interaction network were mainly enriched with cell‑division cycle. CCNA2 and PBK of the module and their relative pathway cell‑division cycle, and two subnetworks (pancreatic cancer and intercellular adhesion subnetworks) may be pivotal for further understanding of the molecular mechanism of PC.

  20. Cannabinoids increase lung cancer cell lysis by lymphokine-activated killer cells via upregulation of ICAM-1.

    PubMed

    Haustein, Maria; Ramer, Robert; Linnebacher, Michael; Manda, Katrin; Hinz, Burkhard

    2014-11-15

    Cannabinoids have been shown to promote the expression of the intercellular adhesion molecule 1 (ICAM-1) on lung cancer cells as part of their anti-invasive and antimetastatic action. Using lung cancer cell lines (A549, H460) and metastatic cells derived from a lung cancer patient, the present study addressed the impact of cannabinoid-induced ICAM-1 on cancer cell adhesion to lymphokine-activated killer (LAK) cells and LAK cell-mediated cytotoxicity. Cannabidiol (CBD), a non-psychoactive cannabinoid, enhanced the susceptibility of cancer cells to adhere to and subsequently be lysed by LAK cells, with both effects being reversed by a neutralizing ICAM-1 antibody. Increased cancer cell lysis by CBD was likewise abrogated when CBD-induced ICAM-1 expression was blocked by specific siRNA or by antagonists to cannabinoid receptors (CB1, CB2) and to transient receptor potential vanilloid 1. In addition, enhanced killing of CBD-treated cancer cells was reversed by preincubation of LAK cells with an antibody to lymphocyte function associated antigen-1 (LFA-1) suggesting intercellular ICAM-1/LFA-1 crosslink as crucial event within this process. ICAM-1-dependent pro-killing effects were further confirmed for the phytocannabinoid Δ(9)-tetrahydrocannabinol (THC) and R(+)-methanandamide (MA), a hydrolysis-stable endocannabinoid analogue. Finally, each cannabinoid elicited no significant increase of LAK cell-mediated lysis of non-tumor bronchial epithelial cells, BEAS-2B, associated with a far less pronounced (CBD, THC) or absent (MA) ICAM-1 induction as compared to cancer cells. Altogether, our data demonstrate cannabinoid-induced upregulation of ICAM-1 on lung cancer cells to be responsible for increased cancer cell lysis by LAK cells. These findings provide proof for a novel antitumorigenic mechanism of cannabinoids. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Cannabidiol inhibits lung cancer cell invasion and metastasis via intercellular adhesion molecule-1.

    PubMed

    Ramer, Robert; Bublitz, Katharina; Freimuth, Nadine; Merkord, Jutta; Rohde, Helga; Haustein, Maria; Borchert, Philipp; Schmuhl, Ellen; Linnebacher, Michael; Hinz, Burkhard

    2012-04-01

    Cannabinoids inhibit cancer cell invasion via increasing tissue inhibitor of matrix metalloproteinases-1 (TIMP-1). This study investigates the role of intercellular adhesion molecule-1 (ICAM-1) within this action. In the lung cancer cell lines A549, H358, and H460, cannabidiol (CBD; 0.001-3 μM) elicited concentration-dependent ICAM-1 up-regulation compared to vehicle via cannabinoid receptors, transient receptor potential vanilloid 1, and p42/44 mitogen-activated protein kinase. Up-regulation of ICAM-1 mRNA by CBD in A549 was 4-fold at 3 μM, with significant effects already evident at 0.01 μM. ICAM-1 induction became significant after 2 h, whereas significant TIMP-1 mRNA increases were observed only after 48 h. Inhibition of ICAM-1 by antibody or siRNA approaches reversed the anti-invasive and TIMP-1-upregulating action of CBD and the likewise ICAM-1-inducing cannabinoids Δ(9)-tetrahydrocannabinol and R(+)-methanandamide when compared to isotype or nonsilencing siRNA controls. ICAM-1-dependent anti-invasive cannabinoid effects were confirmed in primary tumor cells from a lung cancer patient. In athymic nude mice, CBD elicited a 2.6- and 3.0-fold increase of ICAM-1 and TIMP-1 protein in A549 xenografts, as compared to vehicle-treated animals, and an antimetastatic effect that was fully reversed by a neutralizing antibody against ICAM-1 [% metastatic lung nodules vs. isotype control (100%): 47.7% for CBD + isotype antibody and 106.6% for CBD + ICAM-1 antibody]. Overall, our data indicate that cannabinoids induce ICAM-1, thereby conferring TIMP-1 induction and subsequent decreased cancer cell invasiveness.

  2. Induction of human macrophage vascular endothelial growth factor and intercellular adhesion molecule-1 by Ureaplasma urealyticum and downregulation by steroids.

    PubMed

    Li, Ying-Hua; Brauner, Annelie; Jensen, Jørgen Skov; Tullus, Kjell

    2002-01-01

    Chronic lung disease (CLD) remains a major cause of morbidity for the prematurely born infant. The pathogenesis of CLD is complex and has not been defined entirely. Infection and lung inflammatory events have been thought to play a key role in the development of CLD. However, the contribution of Ureaplasma urealyticum to the development of CLD is debated and steroids produce some improvement in neonates with this disease. The aim of this study was to investigate if U. urealyticum could stimulate macrophages to produce vascular endothelial growth factor (VEGF) and intercellular adhesion molecule-1 (ICAM-1) in vitro, which are potentially associated with both early and later pathological changes in the lung during the development of CLD. In addition, the impact of dexamethasone and budesonide on these processes was examined. We found that U. urealyticum antigen (>/=4 x 10(7) color-changing units/ml) stimulated human macrophages (phorbol 12-myristate 13-acetate-differentiated THP-1 cell line) to produce VEGF and soluble ICAM-1 in a dose-dependent manner (p < 0.05) measured by ELISA. Likewise, cell surface ICAM-1 (CD54) measured by flow cytometry was increased after stimulation with U. urealyticum. This effect was attenuated by budesonide and dexamethasone (p < 0.05). The mRNA expressions of VEGF and ICAM-1 detected by a semi-quantitative reverse transcriptase polymerase chain reaction were also induced in response to U. urealyticum and inhibited by the steroids (p < 0.05). The expression of ICAM-1 was reduced by 85.5% when the TNF-alpha production was neutralized with an anti-TNF-alpha antibody. Our findings imply that U. urealyticum might be involved in the development of CLD of prematurity. Copyright 2002 S. Karger AG, Basel

  3. [Effect of different porcelain-fused-to-metal crown inner metal materials on the level of soluble intercellular adhesion molecule-1 and interleukin-1beta in gingival crevicular fluid].

    PubMed

    Yuan, Tangxia; Zhang, Yanbiao; Wu, Zheng-Hua

    2011-10-01

    To investigate the effect of different inner metal materials of porcelain-fused-to-metal (PFM) crown on periodontal tissue by means of measuring the level of soluble intercellular adhesion molecule-1 (sICAM-1) and interleukin-1beta (IL-1beta) in gingival crevicular fluid (GCF) after PFM restorations. 30 teeth were divided into three groups (Ni-Cr alloy group, Co-Cr alloy group and Au-Pt alloy group, 10 teeth each group), and restored by Ni-Cr alloy, Co-Cr alloy and Au-Pt alloy PFM crown according grouping. At the point of pre-restoration, 6-month and 12-month after cementation, the clinical parameters including plaque index (PLI), gingival index (GI) and gingival crevice depth (GCD) were detected, and GCF was collected from labial and lingual of mesial site and distal site. The level of sICAM-1 and IL-1beta were detected. At the point of 6-month and 12-month after cementation, Ni-Cr alloy group showed significant difference for GI, GCD and all GCF indexes when compared to pre-restoration, Co-Cr alloy group and Au-Pt alloy group (P < 0.05). At the point of 12-month after cementation, Co-Cr alloy group showed significant difference for GI, GCD and all GCF indexes when compared to pre-restoration and Au-Pt alloy group (P < 0.05). All indexes have no significant difference for Au-Pt alloy group during the 12-month experiment times when compared to pre-restoration (P > 0.05). Non-noble metal has bad effect on the periodontal tissue.

  4. Functional variants in intercellular adhesion molecule-1 and toll-like receptor-4 genes are more frequent in children with febrile urinary tract infection with renal parenchymal involvement.

    PubMed

    Hussein, Almontaser; Saad, Khaled; Askar, Eman; Zahran, Asmaa M; Farghaly, Hekma; Metwalley, Kotb; Elderwy, Ahmad A

    2018-02-01

    We studied the functional polymorphisms of intercellular adhesion molecule-1 (ICAM-1) and toll-like receptor-4 (TLR-4) genes and risk of acute pyelonephritis (APN) in children attending Assiut University Children's Hospitals, Egypt, from 2011 to 2015. Urinary tract infections (UTIs) were diagnosed in 380 children: 98 had APN and 282 had lower UTIs. Four single-nucleotide polymorphisms in ICAM-1 and TLR-4 genes were genotyped in all subjects: ICAM-1 rs1799969 Gly241Arg, ICAM-1 rs5498 Glu469Lys, TLR-4 rs4896791 Thr399Ile and TLR-4 rs4896790 Asp299Gly. Patients with APN were significantly more likely to have AA genotype of the ICAM-1 rs5498 (1462 A/G) polymorphism (p = 0.04) than children with lower UTIs and the TLR-4 Asp299Gly GG genotype (p = 0.002) and G allele (p = 0.006) than healthy controls. The association with the ICAM-1 Glu469Lys (1462A/G) was less evident. The GG genotype was associated with a modest relative risk of 1.4 (p = 0.1) of developing APN, but was not an independent odds ratio, at 1.2 (p = 0.48). Functional variants in ICAM-1 and TLR-4 genes were increasingly common in children with febrile UTIs with renal parenchymal involvement, but the ICAM-1 Glu469Lys (1462A/G) association was less evident. TLR4 Asp299Gly might independently increase renal parenchymal infection rather than renal scarring. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  5. Dendritic Cell-specific Intercellular Adhesion Molecule 3-grabbing Non-integrin (DC-SIGN) Recognizes a Novel Ligand, Mac-2-binding Protein, Characteristically Expressed on Human Colorectal Carcinomas*

    PubMed Central

    Nonaka, Motohiro; Ma, Bruce Yong; Imaeda, Hirotsugu; Kawabe, Keiko; Kawasaki, Nobuko; Hodohara, Keiko; Kawasaki, Nana; Andoh, Akira; Fujiyama, Yoshihide; Kawasaki, Toshisuke

    2011-01-01

    Dendritic cell (DC)-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) is a type II transmembrane C-type lectin expressed on DCs such as myeloid DCs and monocyte-derived DCs (MoDCs). Recently, we have reported that DC-SIGN interacts with carcinoembryonic antigen (CEA) expressed on colorectal carcinoma cells. CEA is one of the most widely used tumor markers for gastrointestinal cancers such as colorectal cancer. On the other hand, other groups have reported that the level of Mac-2-binding protein (Mac-2BP) increases in patients with pancreatic, breast, and lung cancers, virus infections such as human immunodeficiency virus and hepatitis C virus, and autoimmune diseases. Here, we first identified Mac-2BP expressed on several colorectal carcinoma cell lines as a novel DC-SIGN ligand through affinity chromatography and mass spectrometry. Interestingly, we found that DC-SIGN selectively recognizes Mac-2BP derived from some colorectal carcinomas but not from the other ones. Furthermore, we found that the α1-3,4-fucose moieties of Le glycans expressed on DC-SIGN-binding Mac-2BP were important for recognition. DC-SIGN-dependent cellular interactions between immature MoDCs and colorectal carcinoma cells significantly inhibited MoDC functional maturation, suggesting that Mac-2BP may provide a tolerogenic microenvironment for colorectal carcinoma cells through DC-SIGN-dependent recognition. Importantly, Mac-2BP was detected as a predominant DC-SIGN ligand expressed on some primary colorectal cancer tissues from certain parts of patients in comparison with CEA from other parts, suggesting that DC-SIGN-binding Mac-2BP bearing tumor-associated Le glycans may become a novel potential colorectal cancer biomarker for some patients instead of CEA. PMID:21515679

  6. Experimental gingivitis, bacteremia and systemic biomarkers: a randomized clinical trial.

    PubMed

    Kinane, D F; Zhang, P; Benakanakere, M; Singleton, J; Biesbrock, A; Nonnenmacher, C; He, T

    2015-12-01

    Bacteremia and systemic inflammatory markers are associated with periodontal and systemic diseases and may be linking mechanisms between these conditions. We hypothesized that in the development of gingival inflammation, systemic markers of inflammation and bacteremia would increase. To study the effect of bacteremia on systemic inflammatory markers, we recruited 80 subjects to participate in an experimental gingivitis study. Subjects were stratified based on gender, smoking and the number of bleeding sites and then randomized to one of two groups: control group (n = 40) or experimental gingivitis group (n = 40). Subjects in the control group conducted an oral hygiene regimen: brushing twice daily with a regular sodium fluoride cavity protection dentifrice and a standard manual toothbrush, flossing twice daily, and mouth rinsing with an anti-cavity fluoride rinse once daily. The experimental group stopped brushing and flossing, and used only the fluoride anti-cavity mouth rinse for 21 d. Seventy-nine of 80 subjects were evaluable. One subject in the control group was excluded from the results due to antibiotic use during the study. Our data showed the experimental gingivitis group exhibited a significant (p < 0.05) increase in dental plaque level and gingival inflammatory indices relative to baseline and the control group but a decrease in bacteremia and soluble intercellular adhesion molecule-1 levels vs. baseline. Bacteremia was negatively correlated with gingival inflammatory indices and soluble intercellular adhesion molecule-1 levels in the experimental gingivitis group, thus negating our hypothesis. We conclude that there are marked differences in systemic cytokine levels over the course of short-term experimentally induced gingivitis and further conclude that a long-term periodontitis study must be considered to address mechanisms whereby oral diseases may affect systemic diseases. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. In Vitro Gluten Challenge Test for Celiac Disease Diagnosis.

    PubMed

    Khalesi, Maryam; Jafari, Seyed Ali; Kiani, Mohammadali; Picarelli, Antonio; Borghini, Raffaele; Sadeghi, Ramin; Eghtedar, Alireza; Ayatollahi, Hosein; Kianifar, Hamid R

    2016-02-01

    The in vitro gluten challenge test is an important diagnostic modality in celiac disease (CD), especially in patients who begin treatment with a gluten-free diet before adequate diagnostic workup or in cases with atypical CD. Available literature was reviewed regarding the accuracy of the in vitro gluten challenge test for CD diagnosis. MEDLINE, Scopus, and Google Scholar were searched, and studies that used serology and bowel biopsy as the criterion standard for diagnosis were included in our study. Data on authors, publication year, characteristics of the patient and control groups, patients' diet, duration of the gluten challenge test, histology findings, endomysial antibody (EMA) and anti-tissue transglutaminase (tTG) levels, CD markers, and intercellular cell adhesion molecule-1, and human leukocyte antigens before and after the gluten challenge test were extracted. Overall, 15 studies were included in this meta-analysis. Pooled sensitivity %/specificity % was 84/99 for EMA after the challenge, 52/96 for EMA without the challenge, 95.5/98.3 for anti-tTG after the challenge, and 95.1/98.3 for anti-tTG without the challenge test. Sensitivity/specificity for immunological markers were 89/97 for the percentage of CD25⁺-lamina propria lymphocytes, 96/91 for the percentage of CD3⁺-lamina propria lymphocytes, and 96.1/85.7 for the percentage of intercellular cell adhesion molecule-1-lamina propria lymphocytes. The factors that increased the sensitivity of EMA were longer test duration, and the evaluation of patients on a gluten-containing diet or short-term gluten-free diet. The in vitro gluten challenge test can be a useful part of the diagnostic workup of CD, rather than only a model to evaluate its mechanisms.

  8. Exercise and coronary heart disease risk markers in South Asian and European men.

    PubMed

    Arjunan, Saravana Pillai; Bishop, Nicolette Claire; Reischak-Oliveira, Alvaro; Stensel, David John

    2013-07-01

    South Asians have a higher-than-average risk of CHD. The reasons for this are unclear, but physical inactivity and/or poor responsiveness to exercise may play a role. This study compared the effect of prior exercise on postprandial triacylglycerol (TAG), glucose, insulin, interleukin-6, and soluble intercellular adhesion molecule-1 concentrations in South Asian and European men. Ten healthy South Asian men (i.e., nine Indian men and one Pakistani man) and 10 healthy European men age 20 to 28 yr completed two 2-d trials (exercise and control) in a randomized crossover design. On the afternoon of day 1 of the exercise trial, participants ran on a treadmill for 60 min at approximately 70% of maximal oxygen uptake. Participants rested on day 1 of the control trial. On day 2 of both trials, participants rested and consumed high-fat (57% of energy content) test meals for breakfast (0 h) and lunch (4 h). Fourteen venous blood samples were collected from a cannula between 0 and 9 h for metabolic measurements. Three-way ANOVA identified higher (P < 0.05) postprandial TAG and insulin concentrations in South Asian versus European men. Exercise lowered postprandial TAG and interleukin-6 and elevated soluble intercellular adhesion molecule-1 concentrations. An interaction effect indicated a greater decrease (22% vs 10%) in TAG area under the concentration versus time curve after exercise in South Asian than in European men. Postprandial TAG and insulin responses to high-fat meals were elevated in these South Asian men, but acute exercise was equally, if not more, effective for reducing postprandial lipemia in South Asian than in European men.

  9. Localization of intercellular adhesion molecule-1 (ICAM-1) in the lungs of silica-exposed mice.

    PubMed Central

    Nario, R C; Hubbard, A K

    1997-01-01

    Intercellular adhesion molecule-1 (ICAM-1) is expressed on a variety of cells including endothelial cells, alveolar epithelial cells, and alveolar macrophages. Endothelial/epithelial cell ICAM-1 participates in the migration of leukocytes out of the blood in response to pulmonary inflammation, whereas alveolar macrophage ICAM-1 may represent cell activation. Our previous studies have shown that there is increased expression of ICAM-1 in lung tissue during acute inflammation following intratracheal injection with silica particles (2 mg/mouse). This increased expression was shown to play a role, in part, in the migration of neutrophils from the circulation into the tissue parenchyma. The aim of the current work is to localize expression of ICAM-1 during acute inflammation in lungs of mice exposed to either silica or the nuisance dust, titanium dioxide. In silica-exposed mice, a significant increase in ICAM-1 was detected on day-1 and localized by immunohistochemistry to aggregates of pulmonary macrophages and to type II epithelial cells. Areas of the lung with increased ICAM-1 expression also showed increased tumor necrosis factor alpha expression. Immunocytochemical staining of bronchoalveolar lavage (BAL) cells demonstrated increased ICAM-1 expression associated with alveolar macrophages 3, 5, and 7 days following silica exposure. Finally, soluble ICAM-1 levels in the BAL fluid were significantly increased in mice exposed to silica on the same days. Titanium dioxide exposure elicited a minimal increase in expression of ICAM-1 in the lungs. These data demonstrate that exposure to the toxic particle silica specifically increases ICAM-1 expression localized to pulmonary macrophages and type II epithelial cells. Images Figure 2. B Figure 2. A Figure 2. D Figure 2. C Figure 3. A Figure 3. B Figure 5. B Figure 5. A Figure 5. C PMID:9400721

  10. Modulation of N-glycosylation by mesalamine facilitates membranous E-cadherin expression in colon epithelial cells☆

    PubMed Central

    Khare, Vineeta; Lang, Michaela; Dammann, Kyle; Campregher, Christoph; Lyakhovich, Alex; Gasche, Christoph

    2014-01-01

    Genome wide association studies have implicated intestinal barrier function genes in the pathogenesis of ulcerative colitis. One of such loci CDH1, encoding E-cadherin, a transmembrane glycoprotein with known tumor suppressor functions, is also linked to the susceptibility to colorectal cancer. Loss of membranous E-cadherin expression is common in both colitis and cancer. We have recently demonstrated that mesalamine (5-ASA); the anti-inflammatory drug used to treat ulcerative colitis, induces membranous expression of E-cadherin and increases intercellular adhesion. Using colorectal cancer epithelial cells with aberrant E-cadherin expression, we investigated the mechanism underlying such an effect of 5-ASA. Post-translational modification of E-cadherin glycosylation was analyzed by biotin/streptavidin detection of sialylated glycoproteins. GnT-III (N-acetylglucosaminyltransferase III) expression was assessed by qRT-PCR, Western blot and immunofluorescence. GnT-III activity was analyzed by reactivity with E-4/L-4-PHA. Expression, localization and interaction of E-cadherin and β-catenin were analyzed by Western blot, immunocytochemistry and RNA interference. 5-ASA activity modulated E-cadherin glycosylation and increased both mRNA and protein levels of GnT-III and its activity as detected by increased E4-lectin reactivity. Intestinal APCMin polyps in mice showed low expression of GnT-III and 5-ASA was effective in increasing its expression. The data demonstrated that remodeling of glycans by GnT-III mediated bisect glycosylation, contributes to the membranous retention of E-cadherin by 5-ASA; facilitating intercellular adhesion. Induction of membranous expression of E-cadherin by 5-ASA is a novel mechanism for mucosal healing in colitis that might impede tumor progression by modulation of GnT-III expression. PMID:24184502

  11. The polymorphisms K469E and G261R of intercellular adhesion molecule-1 and susceptibility to inflammatory bowel disease: a meta-analysis.

    PubMed

    Song, Gwan Gyu; Lee, Young Ho

    2015-01-01

    The aim of this study was to explore whether polymorphisms of intercellular adhesion molecule-1 (ICAM-1) are associated with susceptibility to Crohn's disease (CD) and ulcerative colitis (UC). The authors conducted a meta-analysis on the associations between the polymorphisms K469E and G241R of ICAM-1 and susceptibility to CD and UC. A total of 8 studies with 801 patients with CD, 672 patients with UC, and 1,828 controls were included in the meta-analysis. The meta-analysis revealed no association between CD and the ICAM-1 469E allele among the subjects (OR = 1.175, 95% CI = 0.901-1.533, p = 0.233). However, stratification by ethnicity indicated an association between the ICAM-1 469E allele and CD in Europeans (OR = 1.425, 95% CI = 1.013-2.002, p = 0.042). Meta-analysis using the homozygosity also showed an association with CD in Europeans (OR = 2.054, 95% CI = 1.036-4.073, p = 0.039). The meta-analysis revealed no association between UC and the ICAM-1 K469E polymorphism. No association between CD or UC and the ICAM-1 G241R polymorphism was observed. This meta-analysis demonstrates that the ICAM-1 K469E polymorphism may be associated with susceptibility to CD in Europeans, but no association was found between ICAM-1 K469E and UC. In contrast, the G241R polymorphism was not found to be associated with susceptibility to either CD or UC.

  12. Clinical Significance of Soluble Intercellular Adhesion Molecule-1 and Interleukin-6 in Patients with Extrahepatic Cholangiocarcinoma.

    PubMed

    Shimura, Tatsuo; Shibata, Masahiko; Gonda, Kenji; Kofunato, Yasuhide; Okada, Ryo; Ishigame, Teruhide; Kimura, Takashi; Kenjo, Akira; Marubashi, Shigeru; Kono, Koji; Takenoshita, Seiichi

    2017-09-19

    Purpose/Aim: Although several prognostic factors for extrahepatic cholangiocarcinoma (EHC) have been reported, preoperative prognostic factors have yet to be established. We investigated the serum concentration of angiogenic, inflammatory, and nutritional parameters. Twenty-five patients with EHC were enrolled before starting treatment. Preoperative prognostic factors were identified using multivariate analyses. The serum soluble intercellular adhesion molecule-1 (sICAM-1) levels were significantly higher in the patients with EHC (436.0 ± 43.2 ng/ml) than in the healthy volunteers (228.6 ± 22.0 ng/ml) (p <.001). In addition, the serum IL-6 levels were significantly higher in the patients (18.0 ± 5.6 pg/ml) than in the healthy volunteers (5.7 ± 0.8 pg/ml) (p <.05). The serum IL-6 and sICAM-1 showed a strong correlation (r = 0.559) in the patients with EHC (p <.01). The serum IL-6 (area under the curve = 0.764, p =.030, cut-off level = 11.6) and sICAM-1 (area under the curve = 0.818, p =.007, cutoff level = 322.6) were revealed to be useful as prognostic factors by the receiver operating characteristic curves. The high IL-6 group and the high sICAM-1 group showed poorer DSS than those of the respective low groups. In the multivariate analysis, IL-6 (hazard ratio: 1.050, 95% confidence interval: 1.002-1.100, p =.043) and sICAM-1 (hazard ratio: 1.009, 95% confidence interval: 1.002-1.015, p =.009) were independent prognostic factors for DSS. IL-6 and sICAM-1 were independent preoperative prognostic factors in EHC patients, causing continuous inflammation and malnutrition in collaboration with other pro-angiogenic factors.

  13. Soluble intercellular adhesion molecule-1 and clinical outcomes in patients with acute lung injury

    PubMed Central

    Eisner, Mark D.; Parsons, Polly E.; Thompson, B. Taylor; Conner, Edward R.; Matthay, Michael A.; Ware, Lorraine B.

    2009-01-01

    Objective To determine if levels of soluble intercellular adhesion molecule-1 (sICAM-1), a marker of alveolar epithelial and endothelial injury, differ in patients with hydrostatic pulmonary edema and acute lung injury (ALI) and are associated with clinical outcomes in patients with ALI. Design, setting, and participants Measurement of sICAM-1 levels in (1) plasma and edema fluid from 67 patients with either hydrostatic pulmonary edema or ALI enrolled in an observational, prospective single center study, and (2) in plasma from 778 patients with ALI enrolled in a large multi-center randomized controlled trial of ventilator strategy. Results In the single-center study, levels of sICAM-1 were significantly higher in both edema fluid and plasma (median 938 and 545 ng/ml, respectively) from ALI patients compared to hydrostatic edema patients (median 384 and 177 ng/ml, P < 0.03 for both comparisons). In the multi-center study, higher plasma sICAM-1 levels were associated with poor clinical outcomes in both unadjusted and multivariable models. Subjects with ALI whose plasma sICAM-1 levels increased over the first 3 days of the study had a higher risk of death, after adjusting for other important predictors of outcome (odds ratio 1.48; 95% CI 1.03–2.12, P = 0.03). Conclusions Both plasma and edema fluid levels of sICAM-1 are higher in patients with ALI than in patients with hydrostatic pulmonary edema. Higher plasma sICAM-1 levels and increasing sICAM-1 levels over time are associated with poor clinical outcomes in ALI. Measurement of sICAM-1 levels may be useful for identifying patients at highest risk of poor outcomes from ALI. PMID:18670758

  14. Cell-to-cell communication in plants, animals, and fungi: a comparative review.

    PubMed

    Bloemendal, Sandra; Kück, Ulrich

    2013-01-01

    Cell-to-cell communication is a prerequisite for differentiation and development in multicellular organisms. This communication has to be tightly regulated to ensure that cellular components such as organelles, macromolecules, hormones, or viruses leave the cell in a precisely organized way. During evolution, plants, animals, and fungi have developed similar ways of responding to this biological challenge. For example, in higher plants, plasmodesmata connect adjacent cells and allow communication to regulate differentiation and development. In animals, two main general structures that enable short- and long-range intercellular communication are known, namely gap junctions and tunneling nanotubes, respectively. Finally, filamentous fungi have also developed specialized structures called septal pores that allow intercellular communication via cytoplasmic flow. This review summarizes the underlying mechanisms for intercellular communication in these three eukaryotic groups and discusses its consequences for the regulation of differentiation and developmental processes.

  15. Cell-to-cell communication in plants, animals, and fungi: a comparative review

    NASA Astrophysics Data System (ADS)

    Bloemendal, Sandra; Kück, Ulrich

    2013-01-01

    Cell-to-cell communication is a prerequisite for differentiation and development in multicellular organisms. This communication has to be tightly regulated to ensure that cellular components such as organelles, macromolecules, hormones, or viruses leave the cell in a precisely organized way. During evolution, plants, animals, and fungi have developed similar ways of responding to this biological challenge. For example, in higher plants, plasmodesmata connect adjacent cells and allow communication to regulate differentiation and development. In animals, two main general structures that enable short- and long-range intercellular communication are known, namely gap junctions and tunneling nanotubes, respectively. Finally, filamentous fungi have also developed specialized structures called septal pores that allow intercellular communication via cytoplasmic flow. This review summarizes the underlying mechanisms for intercellular communication in these three eukaryotic groups and discusses its consequences for the regulation of differentiation and developmental processes.

  16. Rapid detection of urinary soluble intercellular adhesion molecule-1 for determination of lupus nephritis activity.

    PubMed

    Wang, Yanyun; Tao, Ye; Liu, Yi; Zhao, Yi; Song, Chao; Zhou, Bin; Wang, Tao; Gao, Linbo; Zhang, Lin; Hu, Huaizhong

    2018-06-01

    The current methods of monitoring the activity of lupus nephritis (LN) may cause unnecessary hospital visits or delayed immunosuppressive therapy. We aimed to find a urinary biomarker that could be developed as a home-based test for monitoring the activity of LN.Urine samples were collected immediately before a renal biopsy from patients of suspected active LN, and also from patients with inactive LN, systemic lupus erythematous without LN or healthy controls. Biomarker search was conducted on a cytokine antibody array and confirmation was done by quantitative evaluation with enzyme-linked immunosorbent assay. The Mann-Whiney test or Student t test was used to compare the levels of 9 cytokines between different groups. The sensitivity and specificity of each cytokine for diagnosis of LN was evaluated by receiver operating characteristic curve. A rapid test based on colloidal gold immunochromatography was then developed for bedside or home use. Furthermore, an experimental e-healthcare system was constructed for recording and sharing the results of the rapid test a cloud-assisted internet of things (IoT) consisting of a sensing device, an IoT device and a cloud server.Adiponectin (Acrp30), soluble intercellular cell adhesion molecule-1 (sICAM-1), neural cell adhesion molecule 1 (NCAM-1), and CD26 were significantly higher in urine samples of active LN patients. sICAM-1 appeared more sensitive and specific among these candidates. When the cut-off value of sICAM-1 was set at 1.44 ng/mL, the sensitivity reached 98.33% with a specificity at 85.71%. The sICAM-1 strip test showed comparable sensitivity of 95% and a specificity of 83.3% for assessing the LN activity. Meanwhile, the e-healthcare system was able to conveniently digitize and share the sICAM-1 rapid test results.sICAM-1 appeared to be an excellent biomarker for monitoring LN activity. The e-healthcare system with cloud-assisted IoT could assist the digitalization and sharing of the bedside or home-based sICAM-1 test results.

  17. Microvascular hemodynamics and in vivo evidence for the role of intercellular adhesion molecule-1 in the sequestration of infected red blood cells in a mouse model of lethal malaria.

    PubMed

    Kaul, D K; Liu, X D; Nagel, R L; Shear, H L

    1998-02-01

    The cytoadherence of infected red blood cells (IRBCs) to the vascular endothelium is the major cause of IRBC sequestration and vessel blockage in the cerebral form of human malaria. Among the rodent models of malaria, Plasmodium yoelii 17XL-infected mice show many similarities with the human cerebral malaria caused by P. falciparum. In both, the sequestration of IRBCs in the brain vessels is secondary to the cytoadherence of IRBCs to the vascular endothelium. Similar to P. falciparum infection in the human but in contrast to P. berghei ANKA infection in mice, P. yoelii 17XL results in little, if any, accumulation of monocytes in the brain. In vivo microcirculatory studies reported here were designed to further understand the hemodynamic aspects and mechanisms underlying cytoadherence of IRBCs in the P. yoelii model using the easily accessible cremaster muscle vasculature. The results show significant decreases in arteriovenous red blood cell velocities (Vrbc) and wall shear rates in the microcirculation of P. yoelii-infected mice, with a maximal decrease occurring in small-diameter postcapillary venules, the main sites of cytoadherence. This reflects contributions from IRBC cytoadherence as well as from increased rigidity of parasitized red blood cells. No cytoadherence is observed in arterioles of the infected mice despite decreased wall shear rates, indicating that endothelial receptors for cytoadherence are restricted to venules. Infusion of a monoclonal antibody (MAb) against the intercellular adhesion molecule-1 (ICAM-1) resulted in significant increases in both arteriolar and venular Vrbc and wall shear rates, accompanied by detachment of adhered IRBCs at some venular sites. The peripheral blood smears taken after the MAb infusion showed a distinct increase in the percentage of schizonts, again indicating detachment and/or prevention of cytoadherence. An MAb against the vascular cell adhesion molecule-1 (VCAM-1) as well as an irrelevant control antibody had no effect on these parameters. These results provide the first in vivo microcirculatory evidence indicating involvement of ICAM-1, but not of VCAM-1, in the sequestration of IRBCs in a rodent model of cerebral malaria.

  18. Switch from intracellular to intercellular invasion during water stress-tolerant legume nodulation

    PubMed Central

    Goormachtig, Sofie; Capoen, Ward; James, Euan K.; Holsters, Marcelle

    2004-01-01

    Rhizobia colonize their legume hosts by different modes of entry while initiating symbiotic nitrogen fixation. Most legumes are invaded via growing root hairs by the root hair-curl mechanism, which involves epidermal cell responses. However, invasion of a number of tropical legumes happens through fissures at lateral root bases by cortical, intercellular crack entry. In the semiaquatic Sesbania rostrata, the bacteria entered via root hair curls under nonflooding conditions. Upon flooding, root hair growth was prevented, invasion on accessible root hairs was inhibited, and intercellular invasion was recruited. The plant hormone ethylene was involved in these processes. The occurrence of both invasion pathways on the same host plant enabled a comparison to be made of the structural requirements for the perception of nodulation factors, which were more stringent for the epidermal root hair invasion than for the cortical intercellular invasion at lateral root bases. PMID:15079070

  19. Depression, daily stressors and inflammatory responses to high-fat meals: when stress overrides healthier food choices.

    PubMed

    Kiecolt-Glaser, J K; Fagundes, C P; Andridge, R; Peng, J; Malarkey, W B; Habash, D; Belury, M A

    2017-03-01

    Depression, stress and diet can all alter inflammation. This double-blind, randomized crossover study addressed the impact of daily stressors and a history of major depressive disorder (MDD) on inflammatory responses to high-fat meals. During two separate 9.5 h admissions, 58 healthy women (38 breast cancer survivors and 20 demographically similar controls), mean age 53.1 years, received either a high saturated fat meal or a high oleic sunflower oil meal. The Daily Inventory of Stressful Events assessed prior day stressors and the Structured Clinical Interview for DSM-IV evaluated MDD. As expected, for a woman with no prior day stressors, C-reactive protein (CRP), serum amyloid A (SAA), intercellular adhesion molecule-1 (sICAM-1) and vascular cell adhesion molecule-1 (sVCAM-1) were higher following the saturated fat meal than the high oleic sunflower oil meal after controlling for pre-meal measures, age, trunk fat and physical activity. But if a woman had prior day stressors, these meal-related differences disappeared-because the stressors heightened CRP, SAA, sICAM-1 and sVCAM-1 responses to the sunflower oil meal, making it look more like the responses to the saturated fat meal. In addition, women with an MDD history had higher post-meal blood pressure responses than those without a similar history. These data show how recent stressors and an MDD history can reverberate through metabolic alterations, promoting inflammatory and atherogenic responses.

  20. Role of AGEs-RAGE system in cardiovascular disease.

    PubMed

    Fukami, Kei; Yamagishi, Sho-Ichi; Okuda, Seiya

    2014-01-01

    Advanced glycation end products (AGEs) are a heterogenous group of molecules formed during a non-enzymatic reaction between proteins and sugar residues. Recently, AGEs and their receptor (receptor for AGEs; RAGE) play a central role in the pathogenesis of cardiovascular disease (CVD), which accounts for disability and high mortality rate in patients with diabetes. AGEs initiate diabetic micro- and macrovascular complications through the structural modification and functional alteration of the extracellular matrix proteins as well as intracellular signaling molecules. Engagement of RAGEs with AGEs elicits intracellular reactive oxygen species (ROS) generation and subsequently activates mitogen-activated protein kinase (MAPK) and nuclear factor kappa-B (NF-κB) signaling, followed by production of several inflammatory and/or profibrotic factors such as vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), plasminogen activator inhibitor-1 (PAI-1) and monocyte chemoattractant protein-1 (MCP-1), thereby being involved in the progression of atherosclerosis. Administration of soluble form of RAGE (sRAGE) could work as a decoy receptor for AGEs and might inhibit the binding of AGEs to RAGE, preventing the development and progression of atherosclerosis in animal models. Furthermore, AGEs/high mobility group box-1 (HMGB-1)-RAGE interaction is involved in heart failure, abdominal aortic aneurysm (AAA) and vascular calcification as well. Thus, blockade of the AGEs/HMGB-1-RAGE system may be a promising therapeutic target for preventing diabetes- and/or age-related CVD. We review here the pathological role of the AGEs/HMGB-1-RAGE system in various types of CVD.

  1. Direct Leukocyte Migration across Pulmonary Arterioles and Venules into the Perivascular Interstitium of Murine Lungs during Bleomycin Injury and Repair

    PubMed Central

    Wang, Ping M.; Kachel, Diane L.; Cesta, Mark F.; Martin, William J.

    2011-01-01

    During acute lung injury and repair, leukocytes are thought to enter the lung primarily across alveolar capillaries and postcapillary venules. We hypothesized that leukocytes also migrate across pulmonary arterioles and venules, which serve as alternative sites for leukocyte influx into the lung during acute lung injury and repair. Lung sections from C57BL/6J mice up to 14 days after intratracheal bleomycin (3.33 U/kg) or saline instillation were assessed by light, fluorescence, confocal, and transmission electron microscopy for evidence of inflammatory cell sequestration and transmigration at these sites. After bleomycin treatment, large numbers of leukocytes (including neutrophils, eosinophils, and monocytes) were present in the vascular lumina and in perivascular interstitia of pulmonary arterioles and venules, as well as within the vascular walls. Leukocytes were observed within well-defined pathways in arteriolar walls and much less structured pathways in venular walls, apparently in the process of transmigration. Intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were expressed at sites of leukocyte interaction with the luminal surface, especially in arterioles. Leukocytes appeared to exit from the vessels near collagen fibers into the perivascular interstitium. Results indicate that leukocytes can directly migrate across arteriolar and venular walls into the perivascular interstitium, which may represent an important but under-recognized pathway for leukocyte influx into the lung during injury and repair. PMID:21641381

  2. Neurochemical Characterization of PSA-NCAM+ Cells in the Human Brain and Phenotypic Quantification in Alzheimer's Disease Entorhinal Cortex.

    PubMed

    Murray, Helen C; Swanson, Molly E V; Dieriks, B Victor; Turner, Clinton; Faull, Richard L M; Curtis, Maurice A

    2018-02-21

    Polysialylated neural cell adhesion molecule (PSA-NCAM) is widely expressed in the adult human brain and facilitates structural remodeling of cells through steric inhibition of intercellular NCAM adhesion. We previously showed that PSA-NCAM immunoreactivity is decreased in the entorhinal cortex in Alzheimer's disease (AD). Based on available evidence, we hypothesized that a loss of PSA-NCAM + interneurons may underlie this reduction. PSA-NCAM expression by interneurons has previously been described in the human medial prefrontal cortex. Here we used postmortem human brain tissue to provide further evidence of PSA-NCAM + interneurons throughout the human hippocampal formation and additional cortical regions. Furthermore, PSA-NCAM + cell populations were assessed in the entorhinal cortex of normal and AD cases using fluorescent double labeling and manual cell counting. We found a significant decrease in the number of PSA-NCAM + cells per mm 2 in layer II and V of the entorhinal cortex, supporting our previous description of reduced PSA-NCAM immunoreactivity. Additionally, we found a significant decrease in the proportion of PSA-NCAM + cells that co-labeled with NeuN and parvalbumin, but no change in the proportion that co-labeled with calbindin or calretinin. These results demonstrate that PSA-NCAM is expressed by a variety of interneuron populations throughout the brain. Furthermore, that loss of PSA-NCAM expression by NeuN + cells predominantly contributes to the reduced PSA-NCAM immunoreactivity in the AD entorhinal cortex. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.

  3. The vascular plant-pathogenic bacterium Ralstonia solanacearum produces biofilms required for its virulence on the surfaces of tomato cells adjacent to intercellular spaces.

    PubMed

    Mori, Yuka; Inoue, Kanako; Ikeda, Kenichi; Nakayashiki, Hitoshi; Higashimoto, Chikaki; Ohnishi, Kouhei; Kiba, Akinori; Hikichi, Yasufumi

    2016-08-01

    The mechanism of colonization of intercellular spaces by the soil-borne and vascular plant-pathogenic bacterium Ralstonia solanacearum strain OE1-1 after invasion into host plants remains unclear. To analyse the behaviour of OE1-1 cells in intercellular spaces, tomato leaves with the lower epidermis layers excised after infiltration with OE1-1 were observed under a scanning electron microscope. OE1-1 cells formed microcolonies on the surfaces of tomato cells adjacent to intercellular spaces, and then aggregated surrounded by an extracellular matrix, forming mature biofilm structures. Furthermore, OE1-1 cells produced mushroom-type biofilms when incubated in fluids of apoplasts including intercellular spaces, but not xylem fluids from tomato plants. This is the first report of biofilm formation by R. solanacearum on host plant cells after invasion into intercellular spaces and mushroom-type biofilms produced by R. solanacearum in vitro. Sugar application led to enhanced biofilm formation by OE1-1. Mutation of lecM encoding a lectin, RS-IIL, which reportedly exhibits affinity for these sugars, led to a significant decrease in biofilm formation. Colonization in intercellular spaces was significantly decreased in the lecM mutant, leading to a loss of virulence on tomato plants. Complementation of the lecM mutant with native lecM resulted in the recovery of mushroom-type biofilms and virulence on tomato plants. Together, our findings indicate that OE1-1 produces mature biofilms on the surfaces of tomato cells after invasion into intercellular spaces. RS-IIL may contribute to biofilm formation by OE1-1, which is required for OE1-1 virulence. © 2015 BSPP AND JOHN WILEY & SONS LTD.

  4. A novel leukocyte adhesion deficiency caused by expressed but nonfunctional β2 integrins Mac-1 and LFA-1

    PubMed Central

    Hogg, Nancy; Stewart, Mairi P.; Scarth, Sarah L.; Newton, Rebecca; Shaw, Jacqueline M.; Law, S.K. Alex; Klein, Nigel

    1999-01-01

    In the leukocyte adhesion deficiency (LAD)-1 syndrome, there is diminished expression of β2(CD18) integrins. This is caused by lesions in the β2-subunit gene and gives rise to recurrent bacterial infections, impaired pus formation, and poor wound healing. We describe a patient with clinical features compatible with a moderately severe phenotype of LAD-1 but who expresses the β2 integrins lymphocyte function– associated molecule (LFA)-1 and Mac-1 at 40%–60% of normal levels. This level of expression should be adequate for normal integrin function, but both the patient's Mac-1 on neutrophils and LFA-1 on T cells failed to bind ligands such as fibrinogen and intercellular adhesion molecule (ICAM)-1, respectively, or to display a β2-integrin activation epitope after adhesion-inducing stimuli. Unexpectedly, divalent cation treatment induced the patient's T cells to bind to ICAM-2 and ICAM-3. Sequencing of the patient's two CD18 alleles revealed the mutations S138P and G273R. Both mutations are in the β2-subunit conserved domain, with S138P a putative divalent cation coordinating residue in the metal ion–dependent adhesion site (MIDAS) motif. After K562 cell transfection with α subunits, the mutated S138P β subunit was coexpressed but did not support function, whereas the G273R mutant was not expressed. In summary, the patient described here exhibits failure of the β2 integrins to function despite adequate levels of cell-surface expression. PMID:9884339

  5. Anti-Inflammatory Effects of Pomegranate Peel Extract in THP-1 Cells Exposed to Particulate Matter PM10

    PubMed Central

    Park, Soojin; Seok, Jin Kyung; Kwak, Jun Yup; Suh, Hwa-Jin; Kim, Young Mi; Boo, Yong Chool

    2016-01-01

    Epidemiological and experimental evidence support health risks associated with the exposure to airborne particulate matter with a diameter of <10 μM (PM10). PM10 stimulates the production of reactive oxygen species (ROS) and inflammatory mediators. Thus, we assumed that natural antioxidants might provide health benefits attenuating hazardous effects of PM10. In the present study, we examined the effects of pomegranate peel extract (PPE) on THP-1 monocytic cells exposed to PM10. PM10 induced cytotoxicity and the production of ROS. It also increased the expression and secretion of inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and monocyte chemoattractant protein-1 (MCP-1), and cell adhesion molecules, such as intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). PPE at 10–100 μg mL−1 attenuated the production of ROS and the expression of TNF-α, IL-1β, MCP-1, and ICAM-1, but not VCAM-1, in THP-1 cells stimulated by PM10 (100 μg mL−1). PPE also attenuated the adhesion of PM10-stimulated THP-1 cells to EA.hy926 endothelial cells. PPE constituents, punicalagin and ellagic acid, attenuated PM10-induced monocyte adhesion to endothelial cells, and punicalagin was less cytotoxic compared to ellagic acid. The present study suggests that PPE and punicalagin may be useful in alleviating inflammatory reactions due to particulate matter. PMID:27247608

  6. Hamamelitannin from Hamamelis virginiana inhibits the tumour necrosis factor-alpha (TNF)-induced endothelial cell death in vitro.

    PubMed

    Habtemariam, Solomon

    2002-01-01

    The tumour necrosis factor-alpha (TNF) inhibitory activity of hamamelitannin from Hamamelis virginiana was investigated by assessing the TNF-mediated EAhy926 endothelial cell death and adhesiveness to monocytes. Treatment of the cells by TNF (25 ng/ml) and actinomycin D (0.1ng/ml) resulted in significant DNA fragmentation (34+/-0.6, n=4) and cytotoxicity (97+/-4.5%, n=6) following treatment for 8 and 24h, respectively. One to 100 microM concentrations of hamamelitannin inhibited the TNF-mediated endothelial cell death and DNA fragmentation in a dose-dependent manner. One hundred % protection against TNF-induced DNA fragmentation and cytotoxicity was obtained for hamamelitannin concentrations higher than 10 microM. The protective effect of hamamelitannin was comparable with that of a related compound epigallocatechin gallate while gallic acid was a weak protective agent (<40% protection). EAhy926 endothelial cells upregulated (by 4- to 7-fold) the surface expression of intercellular adhesion molecule-1 (ICAM-1) and adhesiveness to monocytic U937 cells after treatment with TNF (0.5ng/ml) for 6 or 24h. Concentrations (1-100 microM) of hamamelitannin that inhibited the TNF-mediated cell death and DNA fragmentation, however, failed to inhibit the TNF-induced ICAM-1 expression and EAhy926 cell adhesiveness to U937 cells. Thus, hamamelitannin inhibits the TNF-mediated endothelial cell death without altering the TNF-induced upregulation of endothelial adhesiveness. The observed anti-TNF activity of hamamelitannin may explain the antihamorrhaegic use of H. virginiana in traditional medicine and its claimed use as a protective agent for UV radiation.

  7. CLASP2 interacts with p120-catenin and governs microtubule dynamics at adherens junctions

    PubMed Central

    Shahbazi, Marta N.; Megias, Diego; Epifano, Carolina; Akhmanova, Anna; Gundersen, Gregg G.; Fuchs, Elaine

    2013-01-01

    Classical cadherins and their connections with microtubules (MTs) are emerging as important determinants of cell adhesion. However, the functional relevance of such interactions and the molecular players that contribute to tissue architecture are still emerging. In this paper, we report that the MT plus end–binding protein CLASP2 localizes to adherens junctions (AJs) via direct interaction with p120-catenin (p120) in primary basal mouse keratinocytes. Reductions in the levels of p120 or CLASP2 decreased the localization of the other protein to cell–cell contacts and altered AJ dynamics and stability. These features were accompanied by decreased MT density and altered MT dynamics at intercellular junction sites. Interestingly, CLASP2 was enriched at the cortex of basal progenitor keratinocytes, in close localization to p120. Our findings suggest the existence of a new mechanism of MT targeting to AJs with potential functional implications in the maintenance of proper cell–cell adhesion in epidermal stem cells. PMID:24368809

  8. Endothelium dysfunction markers in patients with diabetic retinopathy.

    PubMed

    Siemianowicz, Krzysztof; Francuz, Tomasz; Gminski, Jan; Telega, Alicja; Syzdól, Marcin

    2005-03-01

    Diabetes mellitus leads to endothelium dysfunction and an accelerated progression of atherosclerosis. Vascular complications of diabetes mellitus can affect not only large and medium arteries resulting in coronary heart disease and peripheral arteries diseases, but also small vessels leading to retinopathy and nephropathy. Intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1), E-selectin and von Willebrand factor (vWF) are considered as markers of endothelium dysfunction. The aim of our study was to evaluate plasma levels of ICAM-1, VCAM-1, E-selectin and vWF in patients with type 2 diabetes mellitus receiving insulin therapy and who had diabetic non-proliferative retinopathy, proliferative retinopathy, or did not develop diabetic retinopathy. There were no statistically significant differences between studied groups in any of evaluated endothelium dysfunction markers. There was no statistically significant correlation between measured parameters and a period of diabetic history. None of the studied markers presented a significant correlation with a period of insulin treatment.

  9. [Behavior of soluble L-selectin in HIV infected children].

    PubMed

    Gaddi, E; Balbaryski, J; Cantisano, C; Barboni, G; Candi, M; Quiroz, H; Giraudi, V

    2001-01-01

    L-selectin is an adhesion molecule that is responsible for the initial attachment of leukocytes to endothelium. After leukocyte activation L-selectin is endoproteolytically released from the cell surface. In order to analyze the relationship between soluble L-selectin (sL-selectin) and parameters of immune activation and disease progression, 51 HIV infected children and 15 healthy controls were studied. Serum L-selectin concentrations were significantly higher in HIV infected children than in the control group. Levels of sL-selectin were higher in HIV infected patients with severe immunologic suppression than in those with moderate or no evidence of suppression. A positive correlation between sL-selectin levels and LTCD8 counts, sL-selectin and soluble intercellular adhesion molecule-1 (sICAM-1) and immunogobulin A (IgA) levels was detected. On the contrary sL-selectin concentration did not correlate with plasmatic viral load. The correlation with parameters of immune activation may implicate involvement of sL-selectin in the immunopathogenesis of HIV infection.

  10. New domains of neural cell-adhesion molecule L1 implicated in X-linked hydrocephalus and MASA syndrome

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jouet, M.; Kenwick, S.; Moncla, A.

    1995-06-01

    The neural cell-adhesion molecule L1 is involved in intercellular recognition and neuronal migration in the CNS. Recently, we have shown that mutations in the gene encoding L1 are responsible for three related disorders; X-linked hydrocephalus, MASA (mental retardation, aphasia, shuffling gait, and adducted thumbs) syndrome, and spastic paraplegia type I (SPG1). These three disorders represent a clinical spectrum that varies not only between families but sometimes also within families. To date, 14 independent L1 mutations have been reported and shown to be disease causing. Here we report nine novel L1 mutations in X-linked hydrocephalus and MASA-syndrome families, including the firstmore » examples of mutations affecting the fibronectin type III domains of the molecule. They are discussed in relation both to phenotypes and to the insights that they provide into L1 function. 39 refs., 5 figs., 3 tabs.« less

  11. p120 catenin associates with kinesin and facilitates the transport of cadherin–catenin complexes to intercellular junctions

    PubMed Central

    Chen, Xinyu; Kojima, Shin-ichiro; Borisy, Gary G.; Green, Kathleen J.

    2003-01-01

    p120 catenin (p120) is a component of adherens junctions and has been implicated in regulating cadherin-based cell adhesion as well as the activity of Rho small GTPases, but its exact roles in cell–cell adhesion are unclear. Using time-lapse imaging, we show that p120-GFP associates with vesicles and exhibits unidirectional movements along microtubules. Furthermore, p120 forms a complex with kinesin heavy chain through the p120 NH2-terminal head domain. Overexpression of p120, but not an NH2-terminal deletion mutant deficient in kinesin binding, recruits endogenous kinesin to N-cadherin. Disruption of the interaction between N-cadherin and p120, or the interaction between p120 and kinesin, leads to a delayed accumulation of N-cadherin at cell–cell contacts during calcium-initiated junction reassembly. Our analyses identify a novel role of p120 in promoting cell surface trafficking of cadherins via association and recruitment of kinesin. PMID:14610057

  12. Surface Expression of Precursor N-cadherin Promotes Tumor Cell Invasion12

    PubMed Central

    Maret, Deborah; Gruzglin, Eugenia; Sadr, Mohamad Seyed; Siu, Vincent; Shan, Weisong; Koch, Alexander W; Seidah, Nabil G; Del Maestro, Rolando F; Colman, David R

    2010-01-01

    The expression of N-cadherin (NCAD) has been shown to correlate with increased tumor cell motility and metastasis. However, NCAD-mediated adhesion is a robust phenomenon and therefore seems to be inconsistent with the “release” from intercellular adhesion required for invasion. We show that in the most invasive melanoma and brain tumor cells, altered posttranslational processing results in abundant nonadhesive precursor N-cadherin (proNCAD) at the cell surface, although total NCAD levels remain constant. We demonstrate that aberrantly processed proNCAD promotes cell migration and invasion in vitro. Furthermore, in human tumor specimens, we find high levels of proNCAD as well, supporting an overall conclusion that proNCAD and mature NCAD coexist on these tumor cell surfaces and that it is the ratio between these functionally antagonistic moieties that directly correlates with invasion potential. Our work provides insight into what may be a widespread mechanism for invasion and metastasis and challenges the current dogma of the functional roles played by classic cadherins in tumor progression. PMID:21170270

  13. M-cadherin and its sisters in development of striated muscle.

    PubMed

    Kaufmann, U; Martin, B; Link, D; Witt, K; Zeitler, R; Reinhard, S; Starzinski-Powitz, A

    1999-04-01

    Cadherins are calcium-dependent, transmembrane intercellular adhesion proteins with morphoregulatory functions in the development and maintenance of tissues. In the development of striated muscle, the expression and function of mainly M-, N-, and R-cadherin has been studied so far. While these three cadherins are expressed in skeletal muscle cells, of these only N-cadherin is expressed in cardiac muscle. In this review, M-, N-, and R-cadherin are discussed as important players in the terminal differentiation and possibly also in the commitment of skeletal muscle cells. Furthermore, reports are described which evaluate the essential role of N-cadherin in the formation of heart tissue.

  14. Structural basis of Staphylococcus epidermidis biofilm formation: mechanisms and molecular interactions

    PubMed Central

    Büttner, Henning; Mack, Dietrich; Rohde, Holger

    2015-01-01

    Staphylococcus epidermidis is a usually harmless commensal bacterium highly abundant on the human skin. Under defined predisposing conditions, most importantly implantation of a medical device, S. epidermidis, however, can switch from a colonizing to an invasive life style. The emergence of S. epidermidis as an opportunistic pathogen is closely linked to the biofilm forming capability of the species. During the past decades, tremendous advance regarding our understanding of molecular mechanisms contributing to surface colonization has been made, and detailed information is available for several factors active during the primary attachment, accumulative or dispersal phase of biofilm formation. A picture evolved in which distinct factors, though appearing to be redundantly organized, take over specific and exclusive functions during biofilm development. In this review, these mechanisms are described in molecular detail, with a highlight on recent insights into multi-functional S. epidermidis cell surface proteins contributing to surface adherence and intercellular adhesion. The integration of distinct biofilm-promoting factors into regulatory networks is summarized, with an emphasis on mechanism that could allow S. epidermidis to flexibly adapt to changing environmental conditions present during colonizing or invasive life-styles. PMID:25741476

  15. Establishment of cell-cell junctions depends on the oligomeric states of VE-cadherin

    PubMed Central

    Bibert, Stéphanie; Ayari, Hélène; Riveline, Daniel; Concord, Evelyne; Hermant, Bastien; Vernet, Thierry; Gulino-Debrac, Danièle

    2008-01-01

    Specifically expressed at intercellular adherens junctions of endothelial cells, VE-cadherin is a receptor that exhibits particular self-association properties. Indeed, in vitro studies demonstrated that the extracellular part of VE-cadherin elaborates Ca++-dependent hexameric structures. We hypothesized that this assembly could be at the basis of a new cadherin-mediated cell-cell adhesion mechanism. To verify this assumption, we first demonstrated that VE-cadherin can elaborate hexamers at the cell surface of confluent endothelial cells. Second, mutations were introduced within the extracellular part of VE-cadherin to destabilize the hexamer. Following an in vitro screening, three mutants were selected, among which, one is able to elaborate only dimers. The selected mutations were expressed as C-terminal Green Fluorescent Protein fusions in CHO cells. Despite their capacity to elaborate nascent cell-cell contacts, the mutants seem to be rapidly degraded and or internalized. Altogether, our results suggest that the formation of VE-cadherin hexamers protects this receptor and might allow the elaboration of mature endothelial cell-cell junctions. PMID:18343874

  16. Intercellular signalling in Stigmatella aurantiaca.

    PubMed

    Plaga, W; Ulrich, S H

    1999-12-01

    The myxobacterium Stigmatella aurantiaca is a prokaryotic model used to study intercellular signalling and the genetic determination of morphogenesis. Signalling factors and genes required for the generation of the elaborate multicellular fruiting body are to be identified. Recently, the structure of stigmolone, which is the pheromone necessary for fruiting body formation, was elucidated, and genes involved in development were characterised. Progress has also been made in the genetic accessibility of S. aurantiaca.

  17. Does infection with Chlamydia pneumoniae and/or Helicobacter pylori increase the expression of endothelial cell adhesion molecules in humans?

    PubMed

    Schumacher, A; Seljeflot, I; Lerkerød, A B; Sommervoll, L; Otterstad, J E; Arnesen, H

    2002-10-01

    To investigate if Chlamydia pneumoniae and/or Helicobacter pylori seropositivity is associated with elevated levels of soluble endothelial cell adhesion molecules (sCAMs) as markers of atherosclerotic activity. Immunoglobulin A (IgA) and IgG antibodies to the two bacteria, soluble intercellular cell adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1) and E-selectin were measured in coronary heart disease (CHD) patients (n = 193) and age- and sex-matched controls (n = 193). Two different serological methods were used for the detection of Chlamydia antibodies: Labsystems microimmunofluorescence to detect species-specific C. pneumoniae antibodies and Medac's recombinant enzyme-linked immunosorbent assay to detect genus-specific lipopolysaccharide antibodies. The concentrations of sICAM-1 and E-selectin were higher in CHD patients with positive vs. negative Chlamydia lipopolysaccharide IgA (P = 0.044 for both). H. pylori antibodies alone did not predict raised levels of sCAMs, but in CHD patients sICAM-1 was increased with IgA seropositivity to both bacteria compared to double seronegativity (P = 0.034). Concentrations of sVCAM-1 were elevated in CHD patients with double IgA seropositivity compared to those with Chlamydia lipopolysaccharide IgA seropositivity alone (P = 0.018). Our results may indicate that C. pneumoniae contributes to increased inflammation in CHD, and that this contribution is even more pronounced when present in combination with H. pylori IgA antibodies.

  18. HMC05, Herbal Formula, Inhibits TNF-α-Induced Inflammatory Response in Human Umbilical Vein Endothelial Cells

    PubMed Central

    Lee, Jong Suk; Park, Su-Young; Thapa, Dinesh; Kim, Ah Ra; Shin, Heung-Mook; Kim, Jung-Ae

    2011-01-01

    Vascular inflammation has been implicated in the progression of cardiovascular diseases such as atherosclerosis. In the present study, we found that HMC05, an extract from eight different herbal mixtures, dose-dependently inhibited tumor necrosis factor-α (TNF-α)-induced adhesion of monocytes to endothelial cells. Such inhibitory effect of HMC05 correlated with suppressed expression of monocyte chemoattractant protein-1, CC chemokine receptor 2, vascular cell adhesion molecule-1 and intercellular cell adhesion molecule-1. In addition, HMC05 significantly inhibited production of reactive oxygen species (ROS) and nuclear factor (NF)-κB activation by TNF-α. Those inhibitory effects of HMC05 (1–10 μg mL−1) on the TNF-α-induced inflammatory event was similar to those of berberine (1–10 μM), which is a major component of HMC05 and one of herbal compounds known to have vasorelaxing and lipid-lowering activities. However, berberine significantly reduced the viability of HUVECs in a time- and concentration-dependent manner. In contrast, HMC05 (1–10 μg ml−1) did not affect the cell viability for up to 48 h treatment. In conclusion, we propose that HMC05 may be a safe and potent herbal formula against vascular inflammation, and its action may be attributable to the inhibition of ROS- and NF-κB-dependent expression of adhesion molecules and chemokines. PMID:19736220

  19. P-selectin, endocan, and some adhesion molecules in obese children and adolescents with non-alcoholic fatty liver disease.

    PubMed

    Ustyol, Ala; Aycan Ustyol, Esra; Gurdol, Figen; Kokali, Funda; Bekpınar, Seldag

    2017-05-01

    There is increasing evidence for a direct relationship between the vascular system and non-alcoholic fatty liver disease (NAFLD). The aim of this study was to investigate endocan and adhesion molecules such as P-selectin derived from the endothelium and platelets in obese children and adolescents with NAFLD. One hundred obese patients and 40 lean controls were enrolled. The obese subjects were divided into two subgroups based on the presence or absence of fatty liver. Blood samples were assayed for endocan, P-selectin, platelet-derived growth factor (PDGF), intercellular cell adhesion molecule (ICAM)-1, and vascular cell adhesion molecule (VCAM)-1. Obese patients with NAFLD presented higher ALT and insulin levels, as well as more profound dyslipidemia when compared with their counterparts without NAFLD. Serum levels of high-sensitivity C-reactive protein, VCAM-1 and ICAM-1 were found increased in both obese groups, regardless of NAFLD. In obese subjects with NAFLD, decreased P-selectin levels (51.6 ± 4.14 ng/mL) were detected as compared with the obese (72.3 ± 4.23) and control (74.2 ± 6.97) subjects. Furthermore, circulating P-selectin levels were closely associated with endocan levels (r = 0.852, p < 0.001). Childhood obesity leads to vascular inflammation and therefore may cause a predisposition to atherosclerosis at an early age. The possible outcome of decreased P-selectin levels with NAFLD development must be further investigated.

  20. Brain endothelial adhesion molecule expression in experimental colitis.

    PubMed

    Sans, M; Kawachi, S; Soriano, A; Palacín, A; Morise, Z; Granger, D N; Piqué, J M; Grisham, M B; Panés, J

    2001-04-01

    1) To determine if endothelial expression of adhesion molecules involved in leukocyte recruitment is increased in the brain and other organs in four different models of experimental colitis, and 2) to investigate whether leukocyte infiltration occurs in the brain of colitic animals. Endothelial vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) expression was quantified, using the dual radiolabeled antibody technique in rats with trinitrobenzenesulfonic acid (TNBS)-induced colitis, in mice with dextran sulfate sodium (DSS)-induced colitis, in SCID mice reconstituted with CD45RBhigh T-cells, and in IL-10-/- mice. Leukocyte infiltration in the brain of TNBS-induced colitic rats was assessed by myeloperoxidase activity and immunohistochemical staining with anti-CD45 monoclonal antibody. Marked upregulation of brain endothelial VCAM-1 (2- to 5.5-fold) was consistently found in colitic animals in the four models studied. Brain VCAM-1 strongly correlated with colon VCAM-1 and colon weight. By contrast, upregulation of brain ICAM-1 in colitic animals was only observed in the CD45RBhigh transfer (3-fold) and the TNBS-induced (1.5-fold models). Heart and muscle VCAM-1 and ICAM-1 were not upregulated in colitic animals in the majority of models studied. There was no leukocyte infiltration into the brain of TNBS-induced colitic rats. Our study demonstrates a marked and specific upregulation of endothelial VCAM-1 in the brain of colitic animals. This activation of cerebral endothelial cells was not associated with an infiltration of leukocytes into brain tissue.

  1. DEPTOR regulates vascular endothelial cell activation and proinflammatory and angiogenic responses.

    PubMed

    Bruneau, Sarah; Nakayama, Hironao; Woda, Craig B; Flynn, Evelyn A; Briscoe, David M

    2013-09-05

    The maintenance of normal tissue homeostasis and the prevention of chronic inflammatory disease are dependent on the active process of inflammation resolution. In endothelial cells (ECs), proinflammation results from the activation of intracellular signaling responses and/or the inhibition of endogenous regulatory/pro-resolution signaling networks that, to date, are poorly defined. In this study, we find that DEP domain containing mTOR interacting protein (DEPTOR) is expressed in different microvascular ECs in vitro and in vivo, and using a small interfering RNA (siRNA) knockdown approach, we find that it regulates mammalian target of rapamycin complex 1 (mTORC1), extracellular signal-regulated kinase 1/2, and signal transducer and activator of transcription 1 activation in part through independent mechanisms. Moreover, using limited gene arrays, we observed that DEPTOR regulates EC activation including mRNA expression of the T-cell chemoattractant chemokines CXCL9, CXCL10, CXCL11, CX3CL1, CCL5, and CCL20 and the adhesion molecules intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 (P < .05). DEPTOR siRNA-transfected ECs also bound increased numbers of peripheral blood mononuclear cells (P < .005) and CD3+ T cells (P < .005) in adhesion assays in vitro and had increased migration and angiogenic responses in spheroid sprouting (P < .01) and wound healing (P < .01) assays. Collectively, these findings define DEPTOR as a critical upstream regulator of EC activation responses and suggest that it plays an important role in endogenous mechanisms of anti-inflammation and pro-resolution.

  2. Leonurine protects against tumor necrosis factor-α-mediated inflammation in human umbilical vein endothelial cells.

    PubMed

    Liu, Xinhua; Pan, Lilong; Wang, Xianli; Gong, Qihai; Zhu, Yi Zhun

    2012-05-01

    Leonurine, a bioactive alkaloid compound in Herba leonuri, has various pharmacological activities, including antioxidant and anti-apoptotic capacities. This study was conducted to test the hypothesis that leonurine was able to attenuate tumor necrosis factor (TNF)-α-induced human umbilical vein endothelial cells (HUVEC) activation and the underlying molecular mechanisms. Mitogen-activated protein kinases (MAPK) activation, nuclear factor-κB (NF-κB) activation, and inflammatory mediators expression were detected by Western blot or enzyme-liked immunosorbent assay, intracellular reactive oxygen species (ROS) and NF-κB p65 translocation were measured by immunofluorescence, endothelial cell-monocyte interaction was detected by microscope. Leonurine inhibited U937 cells adhesion to TNF-α-activated HUVEC in a concentration dependent manner. Treatment with leonurine blocked TNF-α-induced mRNA and protein expression of adhesion molecules (intercellular adhesion molecule-1 and vascular cell adhesion molecule-1), cyclooxygenase-2, and monocyte chemoattractant protein-1 in endothelial cells. In addition, leonurine attenuated TNF-α-induced intracellular ROS production in HUVEC. Furthermore, leonurine also suppressed the TNF-α-activated p38 phosphorylation and IκBα degradation. Subsequently, reduced NF-κB p65 phosphorylation, nuclear translocation, and DNA-binding activity were also observed. Our results demonstrated for the first time that the anti-inflammatory properties of leonurine in endothelial cells, at least in part, through suppression of NF-κB activation, which may have a potential therapeutic use for inflammatory vascular diseases. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  3. Soy-Leaf Extract Exerts Atheroprotective Effects via Modulation of Krüppel-Like Factor 2 and Adhesion Molecules

    PubMed Central

    Han, Jong-Min; Li, Hua; Cho, Moon-Hee; Baek, Seung-Hwa; Lee, Chul-Ho; Park, Ho-Yong; Jeong, Tae-Sook

    2017-01-01

    Soy-leaf extracts exert their cardioprotective effects by inducing endothelium-dependent vasodilation in the arteries, and they favorably modulate the serum lipid profile. In this study, we investigated the atheroprotective effects of an ethanol extract of soy leaf (ESL) in human umbilical vein endothelial cells (HUVECs) and high-cholesterol diet (HCD)-fed low-density lipoprotein receptor deficient (LDLR−/−) mice. ESL induced the expression of Krüppel-like factor 2 (KLF2), an endothelial transcription factor, and endothelial nitric oxide synthase (eNOS), and suppressed the expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) through moderate inflammatory signal activation, not only in tumor necrosis factor-α (TNF-α)-stimulated HUVECs but also in 7-ketocholesterol (7-KC)-stimulated HUVECs. ESL supplementation reduced aortic lesion formation in Western diet-fed LDLR−/− mice by 46% (p < 0.01) compared to the HCD group. ESL also markedly decreased the aortic expression levels of VCAM-1, ICAM-1, monocyte chemotactic protein-1 (MCP-1), TNF-α, IL-6, IL-1β, matrix metallopeptidase 9 (MMP-9), and fractalkine, while the expression of KLF2 was significantly increased. These results suggest that ESL supplementation has potential for preventing HCD-induced atherosclerosis effectively. PMID:28208647

  4. O-sulfated bacterial polysaccharides with low anticoagulant activity inhibit metastasis.

    PubMed

    Borgenström, Marjut; Wärri, Anni; Hiilesvuo, Katri; Käkönen, Rami; Käkönen, Sanna; Nissinen, Liisa; Pihlavisto, Marjo; Marjamäki, Anne; Vlodavsky, Israel; Naggi, Annamaria; Torri, Giangiacomo; Casu, Benito; Veromaa, Timo; Salmivirta, Markku; Elenius, Klaus

    2007-07-01

    Heparin-like polysaccharides possess the capacity to inhibit cancer cell proliferation, angiogenesis, heparanase-mediated cancer cell invasion, and cancer cell adhesion to vascular endothelia via adhesion receptors, such as selectins. The clinical applicability of the antitumor effect of such polysaccharides, however, is compromised by their anticoagulant activity. We have compared the potential of chemically O-sulfated and N,O-sulfated bacterial polysaccharide (capsular polysaccharide from E. COLI K5 [K5PS]) species to inhibit metastasis of mouse B16-BL6 melanoma cells and human MDA-MB-231 breast cancer cells in two in vivo models. We demonstrate that in both settings, O-sulfated K5PS was a potent inhibitor of metastasis. Reducing the molecular weight of the polysaccharide, however, resulted in lower antimetastatic capacity. Furthermore, we show that O-sulfated K5PS efficiently inhibited the invasion of B16-BL6 cells through Matrigel and also inhibited the in vitro activity of heparanase. Moreover, treatment with O-sulfated K5PS lowered the ability of B16-BL6 cells to adhere to endothelial cells, intercellular adhesion molecule-1, and P-selectin, but not to E-selectin. Importantly, O-sulfated K5PSs were largely devoid of anticoagulant activity. These findings indicate that O-sulfated K5PS polysaccharide should be considered as a potential antimetastatic agent.

  5. Isolation of antioxidative phenolic glucosides from lemon juice and their suppressive effect on the expression of blood adhesion molecules.

    PubMed

    Miyake, Yoshiaki; Mochizuki, Mika; Okada, Miki; Hiramitsu, Masanori; Morimitsu, Yasujiro; Osawa, Toshihiko

    2007-08-01

    Phenolic glucosides having radical scavenging activity were examined from the fraction eluted with 20% methanol on Amberlite XAD-2 resin applied to lemon (Citrus limon) juice by using reversed phase chromatography. Four phenolic glucosides were identified as 1-feruloyl-beta-D-glucopyranoside, 1-sinapoyl-beta-D-glucopyranoside, 6,8-di-C-glucosylapigenin and 6,8-di-C-glucosyldiosmetin by (1)H-NMR, (13)C-NMR, and MS analyses. They exhibited radical scavenging activity for 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide, although the activity was low in comparison with eriocitrin, a potent antioxidant in lemon fruit, and the eriodictyol of its aglycone. The phenolic compounds in lemon juice were examined for their suppressive effect on the expression of blood adhesion molecules by measuring the expression of intercellular adhesion molecule-1 (ICAM-1) in human umbilical vein endothelial cells (HUVECs) induced by necrosis factor-alpha (TNF-alpha). 6,8-Di-C-glucosylapigenin, apigenin, and diosmentin of the flavones were found to significantly suppress the expression of ICAM-1 at 10 muM (P<0.05). The phenolic glucosides isolated in this study were contained in comparative abundance in daidai (Citrus aurantium) and niihime (Citrus unshiu x Citrus tachibana) among the sour citrus juices.

  6. PI3Kδ promotes CD4(+) T-cell interactions with antigen-presenting cells by increasing LFA-1 binding to ICAM-1.

    PubMed

    Garçon, Fabien; Okkenhaug, Klaus

    2016-05-01

    Activation of T lymphocytes by peptide/major histocompatibility complex on antigen-presenting cells (APCs) involves dynamic contacts between the two cells, during which T cells undergo marked morphological changes. These interactions are facilitated by integrins. Activation of the T cells increases the binding of the integrin lymphocyte function-associated antigen 1 (LFA-1) expressed by T cells to intercellular adhesion molecule (ICAM)-1 and ICAM-2 expressed by APCs. The signalling pathways that control integrin affinities are incompletely defined. The phosphoinositide 3-kinases (PI3Ks) generate second-messenger signalling molecules that control cell growth, proliferation, differentiation and trafficking. Here we show that in T cells, PI3Kδ attenuates the activation of Rac1, but sustains the activation of Rap1. Consequently, PI3Kδ increases LFA-1-dependent adhesion to form stable conjugates with APCs. Increased Rap1 activity and LFA-1 adhesion were only in part mediated by the downstream kinase Akt, suggesting the involvement of additional phosphatidylinositol(3,4,5)P3-binding proteins. These results establish a link between PI3K activity, cytoskeletal changes and integrin binding and help explain the impaired T-cell-dependent immune responses in PI3Kδ-deficient mice.

  7. A Key Claudin Extracellular Loop Domain is Critical for Epithelial Barrier Integrity

    PubMed Central

    Mrsny, Randall J.; Brown, G. Thomas; Gerner-Smidt, Kirsten; Buret, Andre G.; Meddings, Jon B.; Quan, Clifford; Koval, Michael; Nusrat, Asma

    2008-01-01

    Intercellular tight junctions (TJs) regulate epithelial barrier properties. Claudins are major structural constituents of TJs and belong to a large family of tetra-spanning membrane proteins that have two predicted extracellular loops (ELs). Given that claudin-1 is widely expressed in epithelia, we further defined the role of its EL domains in determining TJ function. The effects of several claudin-1 EL mimetic peptides on epithelial barrier structure and function were examined. Incubation of model human intestinal epithelial cells with a 27-amino acid peptide corresponding to a portion of the first EL domain (Cldn-153–80) reversibly interfered with epithelial barrier function by inducing the rearrangement of key TJ proteins: occludin, claudin-1, junctional adhesion molecule-A, and zonula occludens-1. Cldn-153–80 associated with both claudin-1 and occludin, suggesting both the direct interference with the ability of these proteins to assemble into functional TJs and their close interaction under physiological conditions. These effects were specific for Cldn-153–80, because peptides corresponding to other claudin-1 EL domains failed to influence TJ function. Furthermore, the oral administration of Cldn-153–80 to rats increased paracellular gastric permeability. Thus, the identification of a critical claudin-1 EL motif, Cldn-153–80, capable of regulating TJ structure and function, offers a useful adjunct to treatments that require drug delivery across an epithelial barrier. PMID:18349130

  8. Identification and Characterization of an Acinetobacter baumannii Biofilm-Associated Protein▿

    PubMed Central

    Loehfelm, Thomas W.; Luke, Nicole R.; Campagnari, Anthony A.

    2008-01-01

    We have identified a homologue to the staphylococcal biofilm-associated protein (Bap) in a bloodstream isolate of Acinetobacter baumannii. The fully sequenced open reading frame is 25,863 bp and encodes a protein with a predicted molecular mass of 854 kDa. Analysis of the nucleotide sequence reveals a repetitive structure consistent with bacterial cell surface adhesins. Bap-specific monoclonal antibody (MAb) 6E3 was generated to an epitope conserved among 41% of A. baumannii strains isolated during a recent outbreak in the U.S. military health care system. Flow cytometry confirms that the MAb 6E3 epitope is surface exposed. Random transposon mutagenesis was used to generate A. baumannii bap1302::EZ-Tn5, a mutant negative for surface reactivity to MAb 6E3 in which the transposon disrupts the coding sequence of bap. Time course confocal laser scanning microscopy and three-dimensional image analysis of actively growing biofilms demonstrates that this mutant is unable to sustain biofilm thickness and volume, suggesting a role for Bap in supporting the development of the mature biofilm structure. This is the first identification of a specific cell surface protein directly involved in biofilm formation by A. baumannii and suggests that Bap is involved in intercellular adhesion within the mature biofilm. PMID:18024522

  9. Periostin: a novel prognostic and therapeutic target for genitourinary cancer?

    PubMed

    Nuzzo, Pier Vitale; Buzzatti, Giulia; Ricci, Francesco; Rubagotti, Alessandra; Argellati, Francesca; Zinoli, Linda; Boccardo, Francesco

    2014-10-01

    Many of the cellular abnormalities present in solid tumors are structural in nature and involve the proteins of the extracellular matrix (ECM). Periostin is a protein produced and secreted by the fibroblasts as a component of the ECM where it is involved in regulating intercellular adhesion. The expression of periostin has an important physiological role during embryogenesis and growth, namely at the level of bone, dental, and cardiac tissues. Many studies indicate that periostin plays an important role for tumor progression in various types of cancer, such as colon, lung, head and neck, breast, ovarian, and prostate. To the best of our knowledge, a limited number of studies have investigated periostin expression in urogenital cancer, such as prostate, bladder, penile, and renal cancer, and no studies were performed in testis cancer. In this review article, we summarize the most recent knowledge of periostin, its genetic and protein structure, and the role of the different isoforms identified and sequenced so far. In particular, we focus our attention on the role of this protein in genitourinary tumors, trying to emphasize the role not only as a possible prognostic marker, but also as a possible target for the development of future anticancer therapies. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. The molecular basis of induction and formation of tunneling nanotubes.

    PubMed

    Kimura, Shunsuke; Hase, Koji; Ohno, Hiroshi

    2013-04-01

    Tunneling nanotubes (TNTs) and associated structures are recently recognized structures for intercellular communication. They are F-actin-containing thin protrusions of the plasma membrane of a cell and allow a direct physical connection to the plasma membranes of remote cells. TNTs and associated structures serve as mediators for intercellular transfer of organelles as well as membrane components and cytoplasmic molecules. Moreover, several pathogens have been shown to exploit these structures to spread among cells. Because of their contribution to normal cellular functions and importance in pathological conditions, studies on TNTs and related structures have accelerated over the past few years. These studies have revealed key molecules for their induction and/or formation; HIV Nef and M-Sec can induce the formation of TNTs in coordination with the remodeling of the actin cytoskeleton and vesicle trafficking.

  11. Autoimmune and infectious skin diseases that target desmogleins

    PubMed Central

    AMAGAI, Masayuki

    2010-01-01

    Desmosomes are intercellular adhesive junctions of epithelial cells that contain two major transmembrane components, the desmogleins (Dsg) and desmocollins (Dsc), which are cadherin-type cell–cell adhesion molecules and are anchored to intermediate filaments of keratin through interactions with plakoglobin and desmoplakin. Desmosomes play an important role in maintaining the proper structure and barrier function of the epidermis and mucous epithelia. Four Dsg isoforms have been identified to date, Dsg1–Dsg4, and are involved in several skin and heart diseases. Dsg1 and Dsg3 are the two major Dsg isoforms in the skin and mucous membranes, and are targeted by IgG autoantibodies in pemphigus, an autoimmune disease of the skin and mucous membranes. Dsg1 is also targeted by exfoliative toxin (ET) released by Staphylococcus aureus in the infectious skin diseases bullous impetigo and staphylococcal scalded skin syndrome (SSSS). ET is a unique serine protease that shows lock and key specificity to Dsg1. Dsg2 is expressed in all tissues possessing desmosomes, including simple epithelia and myocardia, and mutations in this gene are responsible for arrhythmogenic right ventricular cardiomyopathy/dysplasia. Dsg4 plays an important adhesive role mainly in hair follicles, and Dsg4 mutations cause abnormal hair development. Recently, an active disease model for pemphigus was generated by a unique approach using autoantigen-deficient mice that do not acquire tolerance against the defective autoantigen. Adoptive transfer of Dsg3−/− lymphocytes into mice expressing Dsg3 induces stable anti-Dsg3 IgG production with development of the pemphigus phenotype. This mouse model is a valuable tool with which to investigate immunological mechanisms of harmful IgG autoantibody production in pemphigus. Further investigation of desmoglein molecules will continue to provide insight into the unsolved pathophysiological mechanisms of diseases and aid in the development of novel therapeutic strategies with minimal side effects. PMID:20467217

  12. Migration of Toxoplasma gondii–Infected Dendritic Cells across Human Retinal Vascular Endothelium

    PubMed Central

    Furtado, João M.; Bharadwaj, Arpita S.; Ashander, Liam M.; Olivas, Antoinette; Smith, Justine R.

    2012-01-01

    Purpose. Toxoplasma gondii, the parasite responsible for ocular toxoplasmosis, accesses the retina from the bloodstream. We investigated the dendritic cell as a potential taxi for T. gondii tachyzoites moving across the human retinal endothelium, and examined the participation of adhesion molecules and chemokines in this process. Methods. CD14-positive monocytes were isolated from human peripheral blood by antibody-mediated cell enrichment, and cultured in granulocyte-macrophage colony-stimulating factor and interleukin-4 to generate dendritic cells. Transmigration assays were performed over 18 hours in transwells seeded with human retinal endothelial cells and using dendritic cells exposed to laboratory or natural strains of T. gondii tachyzoites. Parasites were tagged with yellow fluorescent protein to verify infection. In some experiments, endothelial monolayers were preincubated with antibody directed against adhesion molecules, or chemokine was added to lower chambers of transwells. Results. Human monocyte–derived dendritic cell preparations infected with laboratory or natural strain T. gondii tachyzoites transmigrated in larger numbers across simulated human retinal endothelium than uninfected dendritic cells (P ≤ 0.0004 in 5 of 6 experiments). Antibody blockade of intercellular adhesion molecule (ICAM)–1, vascular cell adhesion molecule (VCAM)–1, and activated leukocyte cell adhesion molecule (ALCAM) inhibited transmigration (P ≤ 0.007), and CCL21 or CXCL10 increased transmigration (P ≤ 0.031). Conclusions. Transmigration of human dendritic cells across retinal endothelium is increased following infection with T. gondii. Movement may be impacted by locally produced chemokines and is mediated in part by ICAM-1, VCAM-1, and ALCAM. These findings have implications for development of novel therapeutics aimed at preventing retinal infection by T. gondii. PMID:22952125

  13. Shikonin inhibits oxidized LDL-induced monocyte adhesion by suppressing NFκB activation via up-regulation of PI3K/Akt/Nrf2-dependent antioxidation in EA.hy926 endothelial cells.

    PubMed

    Huang, Chin-Shiu; Lin, Ai-Hsuan; Yang, Ting-Chun; Liu, Kai-Li; Chen, Haw-Wen; Lii, Chong-Kuei

    2015-02-01

    Oxidized low-density lipoprotein (oxLDL) is a key contributor to atherogenesis through multiple mechanisms, including the reactive oxygen species (ROS)-mediated nuclear factor-kappaB (NFκB) signaling pathway. Although shikonin, one of the main active components isolated from the Chinese herb Lithospermum erythrorhizon, has been shown to possess cardioprotective, antioxidative, and anti-inflammatory effects, the mechanisms underlying these actions are not well understood. In this study, we used EA.hy926 endothelial-like cells to examine the anti-atherogenic activity of shikonin. Shikonin (0-1 μM) concentration-dependently induced heme oxygenase-1, glutamate cysteine ligase modifier subunit, catalase, superoxide dismutase 1, glutathione peroxidase 1, and glutathione reductase protein and mRNA expression and glutathione content via activation of the phosphatidylinositol 3-kinase (PI3K)/Akt/Nrf2 signaling pathway. In the presence of oxLDL (40 μg/ml), shikonin pretreatment reversed oxLDL-induced ROS production, antioxidant response element reporter activity, NFκB nuclear translocation, and intercellular adhesion molecule (ICAM)-1 and E-selectin expression and suppressed the increase of monocyte adhesion to endothelial cells. Nrf2 knockdown by using RNA interference attenuated the ability of shikonin to inhibit oxLDL-induced NFκB DNA binding activity, adhesion molecule expression, and monocyte adhesion. Taken together, these results suggest that shikonin protects against oxLDL-induced endothelial damage by suppressing ROS/NFκB-mediated ICAM-1 and E-selectin expression via up-regulation of PI3K/Akt/Nrf2-dependent antioxidant enzyme expression. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Profiling of kidney vascular endothelial cell plasma membrane proteins by liquid chromatography-tandem mass spectrometry.

    PubMed

    Liu, Zan; Xu, Bo; Nameta, Masaaki; Zhang, Ying; Magdeldin, Sameh; Yoshida, Yutaka; Yamamoto, Keiko; Fujinaka, Hidehiko; Yaoita, Eishin; Tasaki, Masayuki; Nakagawa, Yuki; Saito, Kazuhide; Takahashi, Kota; Yamamoto, Tadashi

    2013-06-01

    Vascular endothelial cells (VECs) play crucial roles in physiological and pathologic conditions in tissues and organs. Most of these roles are related to VEC plasma membrane proteins. In the kidney, VECs are closely associated with structures and functions; however, plasma membrane proteins in kidney VECs remain to be fully elucidated. Rat kidneys were perfused with cationic colloidal silica nanoparticles (CCSN) to label the VEC plasma membrane. The CCSN-labeled plasma membrane fraction was collected by gradient ultracentrifugation. The VEC plasma membrane or whole-kidney lysate proteins were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis and digested with trypsin in gels for liquid chromatography-tandem mass spectrometry. Enrichment analysis was then performed. The VEC plasma membrane proteins were purified by the CCSN method with high yield (approximately 20 μg from 1 g of rat kidney). By Mascot search, 582 proteins were identified in the VEC plasma membrane fraction, and 1,205 proteins were identified in the kidney lysate. In addition to 16 VEC marker proteins such as integrin beta-1 and intercellular adhesion molecule-2 (ICAM-2), 8 novel proteins such as Deltex 3-like protein and phosphatidylinositol binding clathrin assembly protein (PICALM) were identified. As expected, many key functions of plasma membranes in general and of endothelial cells in particular (i.e., leukocyte adhesion) were significantly overrepresented in the proteome of CCSN-labeled kidney VEC fraction. The CCSN method is a reliable technique for isolation of VEC plasma membrane from the kidney, and proteomic analysis followed by bioinformatics revealed the characteristics of in vivo VECs in the kidney.

  15. Indentation versus Rolling: Dependence of Adhesion on Contact Geometry for Biomimetic Structures.

    PubMed

    Moyle, Nichole; He, Zhenping; Wu, Haibin; Hui, Chung-Yuen; Jagota, Anand

    2018-04-03

    Numerous biomimetic structures made from elastomeric materials have been developed to produce enhancement in properties such as adhesion, static friction, and sliding friction. As a property, one expects adhesion to be represented by an energy per unit area that is usually sensitive to the combination of shear and normal stresses at the crack front but is otherwise dependent only on the two elastic materials that meet at the interface. More specifically, one would expect that adhesion measured by indentation (a popular and convenient technique) could be used to predict adhesion hysteresis in the more practically important rolling geometry. Previously, a structure with a film-terminated fibrillar geometry exhibited dramatic enhancement of adhesion by a crack-trapping mechanism during indentation with a rigid sphere. Roughly isotropic structures such as the fibrillar geometry show a strong correlation between adhesion enhancement in indentation versus adhesion hysteresis in rolling. However, anisotropic structures, such as a film-terminated ridge-channel geometry, surprisingly show a dramatic divergence between adhesion measured by indentation versus rolling. We study this experimentally and theoretically, first comparing the adhesion of the anisotropic ridge-channel structure to the roughly isotropic fibrillar structure during indentation with a rigid sphere, where only the isotropic structure shows adhesion enhancement. Second, we examine in more detail the anomalous anisotropic film-terminated ridge-channel structure during indentation with a rigid sphere versus rolling to show why these structures show a dramatic adhesion enhancement for the rolling case and no adhesion enhancement for indentation.

  16. Epithelial Permeability Alterations in an In Vitro Air-Liquid Interface Model of Allergic Fungal Rhinosinusitis

    PubMed Central

    Den Beste, Kyle A.; Hoddeson, Elizabeth K.; Parkos, Charles A.; Nusrat, Asma; Wise, Sarah K.

    2012-01-01

    Background Chronic rhinosinusitis (CRS) is an inflammatory upper-airway disease with numerous etiologies. Patients with a characteristic subtype of CRS, allergic fungal rhinosinusitis (AFRS), display increased expression of Th2 cytokines and antigen-specific IgE. Various sinonasal inflammatory conditions are associated with alterations in epithelial barrier function. The aim of this study was to compare epithelial permeability and intercellular junctional protein expression amongst cultured primary sinonasal cells from AFRS patients versus non-inflammatory controls. Methods Epithelial cells isolated from paranasal sinus mucosa of AFRS and non-inflammatory control patients were grown to confluence on permeable supports and transitioned to air-liquid interface (ALI). Trans-epithelial resistance (TER) was measured with a horizontal Ussing chamber to characterize the functional permeability of each cell type. After TER recordings were complete, a panel of intercellular junctional proteins was assessed by Western blot and immunofluorescence labeling followed by confocal microscopy. Results After 12 samples were measured from each group, we observed a 41% mean decrease in TER in AFRS cells (296±89 ohms × cm2) compared to control (503±134 ohms × cm2, P=0.006). TER deficits observed in AFRS were associated with decreased expression of the tight junction proteins occludin and Junctional Adhesion Molecule-A (JAM-A), and increased expression of a leaky tight junction protein claudin-2. Conclusions Cultured sinonasal epithelium from AFRS patients displayed increased epithelial permeability and altered expression of intercellular junctional proteins. Given that these cells were not incubated with inflammatory cytokines in vitro, the cultured AFRS epithelial alterations may represent a retained modification in protein expression from the in vivo phenotype. PMID:22927233

  17. Structure of Peptide Sex Pheromone Receptor PrgX and PrgX/Pheromone Complexes and Regulation of Conjugation in Enterococcus faecalis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shi,K.; Brown, C.; Gu, Z.

    2005-01-01

    Many bacterial activities, including expression of virulence factors, horizontal genetic transfer, and production of antibiotics, are controlled by intercellular signaling using small molecules. To date, understanding of the molecular mechanisms of peptide-mediated cell-cell signaling has been limited by a dearth of published information about the molecular structures of the signaling components. Here, we present the molecular structure of PrgX, a DNA- and peptide-binding protein that regulates expression of the conjugative transfer genes of the Enterococcus faecalis plasmid pCF10 in response to an intercellular peptide pheromone signal. Comparison of the structures of PrgX and the PrgX/pheromone complex suggests that pheromone bindingmore » destabilizes PrgX tetramers, opening a 70-bp pCF10 DNA loop required for conjugation repression.« less

  18. Exosomes from iPSCs Delivering siRNA Attenuate Intracellular Adhesion Molecule-1 Expression and Neutrophils Adhesion in Pulmonary Microvascular Endothelial Cells.

    PubMed

    Ju, Zhihai; Ma, Jinhui; Wang, Chen; Yu, Jie; Qiao, Yeru; Hei, Feilong

    2017-04-01

    The pro-inflammatory activation of pulmonary microvascular endothelial cells resulting in continuous expression of cellular adhesion molecules, and subsequently recruiting primed neutrophils to form a firm neutrophils-endothelium (PMN-EC) adhesion, has been examined and found to play a vital role in acute lung injury (ALI). RNA interference (RNAi) is a cellular process through harnessing a natural pathway silencing target gene based on recognition and subsequent degradation of specific mRNA sequences. It opens a promising approach for precision medicine. However, this application was hampered by many obstacles, such as immunogenicity, instability, toxicity problems, and difficulty in across the biological membrane. In this study, we reprogrammed urine exfoliated renal epithelial cells into human induced pluripotent stem cells (huiPSCs) and purified the exosomes (Exo) from huiPSCs as RNAi delivery system. Through choosing the episomal system to deliver transcription factors, we obtained a non-integrating huiPSCs. Experiments in both vitro and vivo demonstrated that these huiPSCs possess the pluripotent properties. The exosomes of huiPSCs isolated by differential centrifugation were visualized by transmission electron microscopy (TEM) showing a typical exosomal appearance with an average diameter of 122 nm. Immunoblotting confirmed the presence of the typical exosomal markers, including CD63, TSG 101, and Alix. Co-cultured PKH26-labeled exosomes with human primary pulmonary microvascular endothelial cells (HMVECs) confirmed that they could be internalized by recipient cells at a time-dependent manner. Then, electroporation was used to introduce siRNA against intercellular adhesion molecule-1 (ICAM-1) into exosomes to form an Exo/siRNA compound. The Exo/siRNA compound efficiently delivered the target siRNA into HMVECs causing selective gene silencing, inhibiting the ICAM-1 protein expression, and PMN-EC adhesion induced by lipopolysaccharide (LPS). These data suggest that huiPSCs exosomes could be used as a natural gene delivery vector to transport therapeutic siRNAs for alleviating inflammatory responses in recipient cells.

  19. 6-Mercaptopurine attenuates adhesive molecules in experimental vasospasm.

    PubMed

    Chang, Chih-Zen; Lin, Chih-Lung; Kassel, Neal F; Kwan, Aij-Lie; Howng, Shen-Long

    2010-05-01

    Adhesion molecules, including intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin, are important inflammatory mediators which are elevated in the serum of patients following aneurysmal subarachnoid hemorrhage (SAH). The authors previously found that 6-mercaptopurine (6-mp) was effective in preventing and reversing arterial narrowing in a rodent SAH model. The present study was to examine whether levels of adhesion molecules were altered after treatment with 6-mp in this animal model. Animals were each injected with autologous blood into the cisterna magna, and intraperitoneal treatment with 6-mp (2 mg/kg) was initiated 1 h before (prevention) or later (treatment). The compound was subsequently administered at 24 and 48 h post-SAH. Blood samples were collected at 72 h post-SAH to measure ICAM-1, VCAM-1, and E-selectin levels. The basilar arteries were harvested and sliced, and their cross-sectional areas were measured. Morphologically, convolution of the internal elastic lamina, distorted endothelial wall, and myonecrosis of the smooth muscle were prominently observed in the SAH only and vehicle-treated SAH groups, but not in the 6-mp-treated SAH group or in healthy controls. No significant differences were found in the levels of VCAM-1 among all groups. However, the levels of E-selectin were increased in all animals subjected to SAH (SAH only and SAH plus vehicle groups) compared with healthy controls (no SAH), but not in the 6-mp group (SAH plus 6-mp treatment and preventive treatment with 6-mp).Likewise, the levels of ICAM-1 in the SAH only and SAH plus vehicle groups were significantly elevated (p < 0.001), and pretreatment and treatment with 6-mp reduced ICAM-1 to control levels. These results show that ICAM-1 and E-selectin may play a role in mediating SAH-induced vasospasm and that a reduction of both adhesive molecules after SAH may partly contribute to the antispastic effect of 6-mp.

  20. The effect of soy protein beverages on serum cell adhesion molecule concentrations in prehypertensive/stage 1 hypertensive individuals.

    PubMed

    Dettmer, Michelle; Alekel, D Lee; Lasrado, Joanne A; Messina, Mark; Carriquiry, Alicia; Heiberger, Kevin; Stewart, Jeanne W; Franke, Warren

    2012-04-01

    Prehypertensive and hypertensive individuals are at increased risk of atherosclerotic cardiovascular disease (CVD), in part because hypertension contributes to endothelial dysfunction and increased cell adhesion molecule expression. Soy protein and isoflavones may favorably alter CVD risk factors, and hence the aim of this study was to determine whether intake of cow's milk compared with soy beverage prepared from whole soy bean (WSB) or soy protein isolate (SPI) would lower soluble cell adhesion molecule concentrations as a means of decreasing CVD risk. We enrolled healthy prehypertensive/stage 1 hypertensive men (n = 60; 18-63 years) and premenopausal women (n = 8; 20-48 years). Participants were randomized to 1 of 3 groups for 8 weeks: cow's milk (600 mL/d), SPI beverage (840 mL/d; 30.1 mg total isoflavones/d), or WSB beverage (840 mL/d; 91.4 mg total isoflavones/d). We measured soluble vascular cell adhesion molecule-1 (VCAM-1), intercellular cell adhesion molecule-1 (ICAM-1), and endothelial-leukocyte adhesion molecule-1 (E-selectin) concentrations at baseline and week 8. Soluble CAM concentrations were not altered by treatment and did not differ between prehypertensive and hypertensive participants. However, analysis of variance indicated a treatment × gender interaction (gender effect) for ICAM-1 (p = 0.0037) but not for E-selectin (p = 0.067) or VCAM-1 (p = 0.16). Men had higher concentrations of ICAM-1 and E-selectin, respectively, at baseline (p = 0.0071, p = 0.049) and week 8 (p = 0.0054, p = 0.038) than women did. Neither intake of cow's milk nor soy beverage for 8 weeks altered soluble CAM concentrations in prehypertensive/stage 1 hypertensive individuals, suggesting that neither type of beverage diminished atherosclerotic CVD risk in mildly hypertensive individuals by way of improving circulating CAM concentrations.

  1. Effects of hierarchical structures and insulating liquid media on adhesion

    NASA Astrophysics Data System (ADS)

    Yang, Weixu; Wang, Xiaoli; Li, Hanqing; Song, Xintao

    2017-11-01

    Effects of hierarchical structures and insulating liquid media on adhesion are investigated through a numerical adhesive contact model established in this paper, in which hierarchical structures are considered by introducing the height distribution into the surface gap equation, and media are taken into account through the Hamaker constant in Lifshitz-Hamaker approach. Computational methods such as inexact Newton method, bi-conjugate stabilized (Bi-CGSTAB) method and fast Fourier transform (FFT) technique are employed to obtain the adhesive force. It is shown that hierarchical structured surface exhibits excellent anti-adhesive properties compared with flat, micro or nano structured surfaces. Adhesion force is more dependent on the sizes of nanostructures than those of microstructures, and the optimal ranges of nanostructure pitch and maximum height for small adhesion force are presented. Insulating liquid media effectively decrease the adhesive interaction and 1-bromonaphthalene exhibits the smallest adhesion force among the five selected media. In addition, effects of hierarchical structures with optimal sizes on reducing adhesion are more obvious than those of the selected insulating liquid media.

  2. Molecular cell biology and physiology of solute transport

    PubMed Central

    Caplan, Michael J.; Seo-Mayer, Patricia; Zhang, Li

    2010-01-01

    Purpose of review An enormous body of research has been focused on exploring the mechanisms through which epithelial cells establish their characteristic polarity. It is clear that under normal circumstances cell–cell contacts mediated by the calcium-dependent adhesion proteins of the intercellular adhesion junctions are required to initiate complete polarization. Furthermore, formation of the tight, or occluding, junctions that limit paracellular permeability has long been thought to help to establish polarity by preventing the diffusion of membrane proteins between the two plasmalemmal domains. This review will discuss several selected kinases and protein complexes and highlight their relevance to transporting epithelial cell polarization. Recent findings Recent work has shed new light on the roles of junctional complexes in establishing and maintaining epithelial cell polarity. In addition, work from several laboratories, suggests that the formation of these junctions is tied to processes that regulate cellular energy metabolism. Summary Junctional complexes and energy sensing kinases constitute a novel class of machinery whose capacity to generate and modulate epithelial cell polarity is likely to have wide ranging and important physiological ramifications. PMID:18695392

  3. HDL-transferred microRNA-223 regulates ICAM-1 expression in endothelial cells

    PubMed Central

    Tabet, Fatiha; Vickers, Kasey C.; Cuesta Torres, Luisa F.; Wiese, Carrie B.; Shoucri, Bassem M.; Lambert, Gilles; Catherinet, Claire; Prado-Lourenco, Leonel; Levin, Michael G.; Thacker, Seth; Sethupathy, Praveen; Barter, Philip J.; Remaley, Alan T.; Rye, Kerry-Anne

    2014-01-01

    High-density lipoproteins (HDL) have many biological functions, including reducing endothelial activation and adhesion molecule expression. We recently reported that HDL transport and deliver functional microRNAs (miRNA). Here we show that HDL suppresses expression of intercellular adhesion molecule 1 (ICAM-1) through the transfer of miR-223 to endothelial cells. After incubation of endothelial cells with HDL, mature miR-223 levels are significantly increased in endothelial cells and decreased on HDL. However, miR-223 is not transcribed in endothelial cells and is not increased in cells treated with HDL from miR-223−/− mice. HDL inhibit ICAM-1 protein levels, but not in cells pretreated with miR-223 inhibitors. ICAM-1 is a direct target of HDL-transferred miR-223 and this is the first example of an extracellular miRNA regulating gene expression in cells where it is not transcribed. Collectively, we demonstrate that HDL’s anti-inflammatory properties are conferred, in part, through HDL-miR-223 delivery and translational repression of ICAM-1 in endothelial cells. PMID:24576947

  4. Identification of New Anti-inflammatory Peptides from Zein Hydrolysate after Simulated Gastrointestinal Digestion and Transport in Caco-2 Cells.

    PubMed

    Liang, Qiufang; Chalamaiah, Meram; Ren, Xiaofeng; Ma, Haile; Wu, Jianping

    2018-02-07

    Chronic inflammation is an underlying contributor to various chronic diseases. The objectives of this study were to investigate the anti-inflammatory activity of zein hydrolysate after simulated gastrointestinal digestion and Caco-2 cell absorption and to identify novel anti-inflammatory peptides after transport across Caco-2 cells. Three zein hydrolysates were prepared and further digested using gastrointestinal proteases; their transports were studied in Caco-2 cells. Anti-inflammatory activity was studied in endothelial EA.hy926 cells. Three zein hydrolysates and their digests significantly decreased the expression of tumor necrosis factor-α (TNF-α) induced pro-inflammatory vascular cell adhesion molecule-1 (VCAM-1) by 37.3-66.0%. Eleven novel peptides with 5-9 amino acid residues were sequenced; three peptides showed strong anti-inflammatory activity by inhibiting the VCAM-1 by 54-38.9% and intercellular cell adhesion molecule-1 (ICAM-1) by 36.5-28.6% at 0.2 mM. A new approach to identify novel anti-inflammatory peptides that could survive gastrointestinal digestion and absorption was developed.

  5. Dendritic Cells Pulsed with Leukemia Cell-Derived Exosomes More Efficiently Induce Antileukemic Immunities

    PubMed Central

    Wei, Wei; Shen, Chang; Deng, Xiaohui; Chen, Linjun; Ma, Liyuan; Hao, Siguo

    2014-01-01

    Dendritic cells (DCs) and tumor cell-derived exosomes have been used to develop antitumor vaccines. However, the biological properties and antileukemic effects of leukemia cell-derived exosomes (LEXs) are not well described. In this study, the biological properties and induction of antileukemic immunity of LEXs were investigated using transmission electron microscopy, western blot analysis, cytotoxicity assays, and animal studies. Similar to other tumor cells, leukemia cells release exosomes. Exosomes derived from K562 leukemia cells (LEXK562) are membrane-bound vesicles with diameters of approximately 50–100 μm and harbor adhesion molecules (e.g., intercellular adhesion molecule-1) and immunologically associated molecules (e.g., heat shock protein 70). In cytotoxicity assays and animal studies, LEXs-pulsed DCs induced an antileukemic cytotoxic T-lymphocyte immune response and antileukemic immunity more effectively than did LEXs and non-pulsed DCs (P<0.05). Therefore, LEXs may harbor antigens and immunological molecules associated with leukemia cells. As such, LEX-based vaccines may be a promising strategy for prolonging disease-free survival in patients with leukemia after chemotherapy or hematopoietic stem cell transplantation. PMID:24622345

  6. Myeloid-Related Protein-14/MRP-14/S100A9/Calgranulin B is Associated with Inflammation in Proliferative Diabetic Retinopathy.

    PubMed

    Abu El-Asrar, Ahmed M; Alam, Kaiser; Siddiquei, Mohammad M; Van den Eynde, Kathleen; Mohammad, Ghulam; De Hertogh, Gert; Opdenakker, Ghislain

    2018-01-01

    To investigate the expression of the leukocyte proteins myeloid-related protein (MRP)-8 and MRP-14 in proliferative diabetic retinopathy (PDR) and the effect of MRP-8/MRP-14 (calprotectin) heterodimer on induction of proinflammatory factors in human retinal microvascular endothelial cells (HRMEC). Epiretinal membranes from 20 patients with PDR and 10 patients with proliferative vitreoretinopathy (PVR), vitreous fluid samples from PDR and non-diabetic subjects and HRMEC were studied by immunohistochemistry and Western blot analysis. MRP-14 expression was localized in endothelial cells, leukocytes and myofibroblasts in all PDR membranes. MRP-8 expression was limited to intravascular leukocytes in 42% of the studied membranes. In PVR membranes, MRP-14 was expressed in leukocytes and myofibroblasts, whereas MRP-8 immunoreactivity was limited to leukocytes. MRP-14 was significantly upregulated in vitreous from PDR patients. MRP-8/MRP-14 (calprotectin) increased expression of intercellular adhesion molecule-1, but attenuated vascular cell adhesion molecule-1 expression in HRMEC. Increased MRP-14 levels are associated with inflammation in PDR.

  7. Aloe-emodin inhibits Staphylococcus aureus biofilms and extracellular protein production at the initial adhesion stage of biofilm development.

    PubMed

    Xiang, Hua; Cao, Fengjiao; Ming, Di; Zheng, Yanyang; Dong, Xiaoyun; Zhong, Xiaobo; Mu, Dan; Li, Bangbang; Zhong, Ling; Cao, Junjie; Wang, Lin; Ma, Hongxia; Wang, Tiedong; Wang, Dacheng

    2017-09-01

    Staphylococcus aureus (S. aureus) biofilms are clinically serious and play a critical role in the persistence of chronic infections due to their ability to resist antibiotics. The inhibition of biofilm formation is viewed as a new strategy for the prevention of S. aureus infections. Here, we demonstrated that minimum inhibitory concentrations (MICs) of aloe-emodin exhibited no bactericidal activity against S. aureus but affected S. aureus biofilm development in a dose-dependent manner. Further studies indicated that aloe-emodin specifically inhibits the initial adhesion and proliferation stages of S. aureus biofilm development. Scanning electron microscopy (SEM) indicated that the S. aureus ATCC29213 biofilm extracellular matrix is mainly composed of protein. Laser scanning confocal microscope assays revealed that aloe-emodin treatment primarily inhibited extracellular protein production. Moreover, the Congo red assay showed that aloe-emodin also reduced the accumulation of polysaccharide intercellular adhesin (PIA) on the cell surface. These findings will provide new insights into the mode of action of aloe-emodin in the treatment of infections by S. aureus biofilms.

  8. Antioxidant Peptides Identified from Ovotransferrin by the ORAC Method Did Not Show Anti-Inflammatory and Antioxidant Activities in Endothelial Cells.

    PubMed

    Jahandideh, Forough; Chakrabarti, Subhadeep; Davidge, Sandra T; Wu, Jianping

    2016-01-13

    Oxygen radical absorbance capacity (ORAC) is a widely used method of measuring antioxidant capacities of various antioxidant components. Surprisingly, 16 antioxidant peptides previously identified from egg protein ovotransferrin using the ORAC method did not show any anti-inflammatory and antioxidant activities in cells. After simulated gastro-intestinal digestion (GID), several peptide digests significantly reduced the expression of tumor necrosis factor-α (TNF-α)-induced pro-inflammatory intercellular cell adhesion molecule-1 (ICAM-1) by 65.7 ± 10.4% and vascular cell adhesion molecule-1 (VCAM-1) by 53.5 ± 9.6% to 61.0 ± 14.5%, but only GWNI reduced TNF-α-activated superoxide generation by 71.0 ± 12.9% when tested with dihydroethidium (DHE) assay. Mass spectrometer analysis identified two new peptides, GWN and GW, in the GWNI digest; however, only GW reduced TNF-α-induced VCAM-1 expression (64.3 ± 20.6%) significantly compared to the TNF-α treated cells. Our study suggested that ORAC lacked biological relevance in assessing bioactive peptides.

  9. Quercetin nanoparticle complex attenuated diabetic nephropathy via regulating the expression level of ICAM-1 on endothelium

    PubMed Central

    Tong, Fei; Liu, Suhuan; Yan, Bing; Li, Xuejun; Ruan, Shiwei; Yang, Shuyu

    2017-01-01

    The purpose of the study was to reveal the therapeutic effect of quercetin (QUE) nanoparticle complex on diabetic nephropathy (DN) by regulating the expression of intercellular adhesion molecular-1 (ICAM-1) on endothelium as compared to free QUE. QUE 10 mg/kg as a single abdominal subcutaneous injection daily for 8 weeks continuously in diabetic rats and 10 mg/kg QUE nanoparticle complex as a single abdominal subcutaneous injection every 5 days, continuously administered for 8 weeks to diabetic rats. Blood and left kidneys were collected; pathological change of kidney, renal function, oxidative stress level, blood glucose level, serum lipid, urine protein, and albumin/creatinine ratio were measured; and neutrophil adhesion, ICAM-1 expression, and CD11b+ cells infiltration were observed. Both QUE and QUE nanoparticle complex preconditioning ameliorated the pathological damage of kidney and improved renal function, alleviated renal oxidative stress injury, restricted inflammatory cells infiltration, and downregulated the ICAM-1 expression as compared to DN group, while QUE nanoparticle complex significantly alleviated this effect. PMID:29123394

  10. Long term exposure to L-arginine accelerates endothelial cell senescence through arginase-II and S6K1 signaling

    PubMed Central

    Xiong, Yuyani; Fru, Michael Forbiteh; Yu, Yi; Montani, Jean-Pierre; Ming, Xiu-Fen; Yang, Zhihong

    2014-01-01

    L-arginine supplementation is proposed to improve health status or as adjunct therapy for diseases including cardiovascular diseases. However, controversial results and even detrimental effects of L-arginine supplementation are reported. We investigate potential mechanisms of L-arginine-induced detrimental effects on vascular endothelial cells. Human endothelial cells were exposed to a physiological (0.1 mmol/L) or pharmacological (0.5 mmol/L) concentration of L-arginine for 30 minutes (acute) or 7 days (chronic). The effects of L-arginine supplementation on endothelial senescence phenotype, i.e., levels of senescence-associated beta-galactosidase, expression of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1, eNOS-uncoupling, arginase-II expression/activity, and mTORC1-S6K1 activity were analyzed. While acute L-arginine treatment enhances endothelial NO production accompanied with superoxide production and activation of S6K1 but no up-regulation of arginase-II, chronic L-arginine supplementation causes endothelial senescence, up-regulation of the adhesion molecule expression, and eNOS-uncoupling (decreased NO and enhanced superoxide production), which are associated with S6K1 activation and up-regulation of arginase-II. Silencing either S6K1 or arginase-II inhibits up-regulation/activation of each other, prevents endothelial dysfunction, adhesion molecule expression, and senescence under the chronic L-arginine supplementation condition. These results demonstrate that S6K1 and arginase-II form a positive circuit mediating the detrimental effects of chronic L-arginine supplementation on endothelial cells. PMID:24860943

  11. DEPTOR regulates vascular endothelial cell activation and proinflammatory and angiogenic responses

    PubMed Central

    Bruneau, Sarah; Nakayama, Hironao; Woda, Craig B.; Flynn, Evelyn A.

    2013-01-01

    The maintenance of normal tissue homeostasis and the prevention of chronic inflammatory disease are dependent on the active process of inflammation resolution. In endothelial cells (ECs), proinflammation results from the activation of intracellular signaling responses and/or the inhibition of endogenous regulatory/pro-resolution signaling networks that, to date, are poorly defined. In this study, we find that DEP domain containing mTOR interacting protein (DEPTOR) is expressed in different microvascular ECs in vitro and in vivo, and using a small interfering RNA (siRNA) knockdown approach, we find that it regulates mammalian target of rapamycin complex 1 (mTORC1), extracellular signal-regulated kinase 1/2, and signal transducer and activator of transcription 1 activation in part through independent mechanisms. Moreover, using limited gene arrays, we observed that DEPTOR regulates EC activation including mRNA expression of the T-cell chemoattractant chemokines CXCL9, CXCL10, CXCL11, CX3CL1, CCL5, and CCL20 and the adhesion molecules intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 (P < .05). DEPTOR siRNA-transfected ECs also bound increased numbers of peripheral blood mononuclear cells (P < .005) and CD3+ T cells (P < .005) in adhesion assays in vitro and had increased migration and angiogenic responses in spheroid sprouting (P < .01) and wound healing (P < .01) assays. Collectively, these findings define DEPTOR as a critical upstream regulator of EC activation responses and suggest that it plays an important role in endogenous mechanisms of anti-inflammation and pro-resolution. PMID:23881914

  12. Vascular cell adhesion molecule-1 (VCAM-1) gene transcription and expression are regulated through an antioxidant-sensitive mechanism in human vascular endothelial cells.

    PubMed Central

    Marui, N; Offermann, M K; Swerlick, R; Kunsch, C; Rosen, C A; Ahmad, M; Alexander, R W; Medford, R M

    1993-01-01

    Oxidative stress and expression of the vascular cell adhesion molecule-1 (VCAM-1) on vascular endothelial cells are early features in the pathogenesis of atherosclerosis and other inflammatory diseases. Regulation of VCAM-1 gene expression may be coupled to oxidative stress through specific reduction-oxidation (redox) sensitive transcriptional or posttranscriptional regulatory factors. In cultured human umbilical vein endothelial (HUVE) cells, the cytokine interleukin 1 beta (IL-1 beta) activated VCAM-1 gene expression through a mechanism that was repressed approximately 90% by the antioxidants pyrrolidine dithiocarbamate (PDTC) and N-acetylcysteine (NAC). Furthermore, PDTC selectively inhibited the induction of VCAM-1, but not intercellular adhesion molecule-1 (ICAM-1), mRNA and protein accumulation by the cytokine tumor necrosis factor-alpha (TNF alpha) as well as the noncytokines bacterial endotoxin lipopolysaccharide (LPS) and double-stranded RNA, poly(I:C) (PIC). PDTC also markedly attenuated TNF alpha induction of VCAM-1-mediated cellular adhesion. In a distinct pattern, PDTC partially inhibited E-selectin gene expression in response to TNF alpha but not to LPS, IL-1 beta, or PIC. TNF alpha and LPS-mediated transcriptional activation of the human VCAM-1 promoter through NF-kappa B-like DNA enhancer elements and associated NF-kappa B-like DNA binding proteins was inhibited by PDTC. These studies suggest a molecular linkage between an antioxidant sensitive transcriptional regulatory mechanism and VCAM-1 gene expression that expands on the notion of oxidative stress as an important regulatory signal in the pathogenesis of atherosclerosis. Images PMID:7691889

  13. Short-term high-fat diet alters postprandial glucose metabolism and circulating vascular cell adhesion molecule-1 in healthy males.

    PubMed

    Numao, Shigeharu; Kawano, Hiroshi; Endo, Naoya; Yamada, Yuka; Takahashi, Masaki; Konishi, Masayuki; Sakamoto, Shizuo

    2016-08-01

    Short-term intake of a high-fat diet aggravates postprandial glucose metabolism; however, the dose-response relationship has not been investigated. We hypothesized that short-term intake of a eucaloric low-carbohydrate/high-fat diet (LCHF) would aggravate postprandial glucose metabolism and circulating adhesion molecules in healthy males. Seven healthy young males (mean ± SE; age: 26 ± 1 years) consumed either a eucaloric control diet (C, approximately 25% fats), a eucaloric intermediate-carbohydrate/intermediate-fat diet (ICIF, approximately 50% fats), or an LCHF (approximately 70% fats) for 3 days. An oral meal tolerance test (MTT) was performed after the 3-day dietary intervention. The concentrations of plasma glucose, insulin, glucagon-like peptide-1 (GLP-1), intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 (VCAM-1) were determined at rest and during MTT. The incremental area under the curve (iAUC) of plasma glucose concentration during MTT was significantly higher in LCHF than in C (P = 0.009). The first-phase insulin secretion indexes were significantly lower in LCHF than in C (P = 0.04). Moreover, the iAUC of GLP-1 and VCAM-1 concentrations was significantly higher in LCHF than in C (P = 0.014 and P = 0.04, respectively). The metabolites from ICIF and C were not significantly different. In conclusion, short-term intake of eucaloric diet containing a high percentage of fats in healthy males excessively increased postprandial glucose and VCAM-1 concentrations and attenuated first-phase insulin release.

  14. Lycopene inhibits NF-κB activation and adhesion molecule expression through Nrf2-mediated heme oxygenase-1 in endothelial cells.

    PubMed

    Yang, Po-Min; Chen, Huang-Zhi; Huang, Yu-Ting; Hsieh, Chia-Wen; Wung, Being-Sun

    2017-06-01

    The endothelial expression of cell adhesion molecules plays a leading role in atherosclerosis. Lycopene, a carotenoid with 11 conjugated double bonds, has been shown to have anti-inflammatory properties. In the present study, we demonstrate a putative mechanism for the anti-inflammatory effects of lycopene. We demonstrate that lycopene inhibits the adhesion of tumor necrosis factor α (TNFα)-stimulated monocytes to endothelial cells and suppresses the expression of intercellular cell adhesion molecule-1 (ICAM-1) at the transcriptional level. Moreover, lycopene was found to exert its inhibitory effects by blocking the degradation of the inhibitory protein, IκBα, following 6 h of pre-treatment. In TNFα-stimulated endothelial cells, nuclear factor-κB (NF-κB) nuclear translocation and transcriptional activity were abolished by up to 12 h of lycopene pre-treatment. We also found that lycopene increased the intracellular glutathione (GSH) level and glutamate-cysteine ligase expression. Subsequently, lycopene induced nuclear factor-erythroid 2 related factor 2 (Nrf2) activation, leading to the increased expression of downstream of heme oxygenase-1 (HO-1). The use of siRNA targeting HO-1 blocked the inhibitory effects of lycopene on IκB degradation and ICAM-1 expression. The inhibitory effects of lycopene thus appear to be mediated through its induction of Nrf2-mediated HO-1 expression. Therefore, the findings of the present study indicate that lycopene suppresses the activation of TNFα-induced signaling pathways through the upregulation of Nrf2-mediated HO-1 expression.

  15. Mechanisms for Cell-to-Cell Transmission of HIV-1

    PubMed Central

    Bracq, Lucie; Xie, Maorong; Benichou, Serge; Bouchet, Jérôme

    2018-01-01

    While HIV-1 infection of target cells with cell-free viral particles has been largely documented, intercellular transmission through direct cell-to-cell contact may be a predominant mode of propagation in host. To spread, HIV-1 infects cells of the immune system and takes advantage of their specific particularities and functions. Subversion of intercellular communication allows to improve HIV-1 replication through a multiplicity of intercellular structures and membrane protrusions, like tunneling nanotubes, filopodia, or lamellipodia-like structures involved in the formation of the virological synapse. Other features of immune cells, like the immunological synapse or the phagocytosis of infected cells are hijacked by HIV-1 and used as gateways to infect target cells. Finally, HIV-1 reuses its fusogenic capacity to provoke fusion between infected donor cells and target cells, and to form infected syncytia with high capacity of viral production and improved capacities of motility or survival. All these modes of cell-to-cell transfer are now considered as viral mechanisms to escape immune system and antiretroviral therapies, and could be involved in the establishment of persistent virus reservoirs in different host tissues. PMID:29515578

  16. Terbinafine inhibits gap junctional intercellular communication

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, Ju Yeun, E-mail: whitewndus@naver.com

    Terbinafine is an antifungal agent that selectively inhibits fungal sterol synthesis by blocking squalene epoxidase. We evaluated the effect of terbinafine on gap junctional intercellular communication (GJIC). Fluorescence recovery after photobleaching (FRAP) and I-YFP GJIC assays revealed that terbinafine inhibits GJIC in a reversible and dose-dependent manner in FRT-Cx43 and LN215 cells. Treatment with terbinafine did not affect Cx43 phosphorylation status or intracellular Ca{sup 2+} concentration, well-known action mechanisms of various GJIC blockers. While a structurally related chemical, naftifine, attenuated GJIC, epigallocatechin gallate, another potent squalene epoxidase inhibitor with a different structure, did not. These results suggest that terbinafine inhibitsmore » GJIC with a so far unknown mechanism of action. - Highlights: • In vitro pharmacological studies were performed on FRT-Cx43 and LN215 cells. • Terbinafine inhibits gap junctional intercellular communication in both cell lines. • The inhibitory effect of terbinafine is reversible and dose-dependent. • Treatment of terbinafine does not alter Cx43 phosphorylation or cytosolic Ca{sup 2+} concentration. • Inhibition of squalene epoxidase is not involved in this new effect of terbinafine.« less

  17. Dominant de novo DSP mutations cause erythrokeratodermia-cardiomyopathy syndrome

    PubMed Central

    Boyden, Lynn M.; Kam, Chen Y.; Hernández-Martín, Angela; Zhou, Jing; Craiglow, Brittany G.; Sidbury, Robert; Mathes, Erin F.; Maguiness, Sheilagh M.; Crumrine, Debra A.; Williams, Mary L.; Hu, Ronghua; Lifton, Richard P.; Elias, Peter M.; Green, Kathleen J.; Choate, Keith A.

    2016-01-01

    Disorders of keratinization (DOK) show marked genotypic and phenotypic heterogeneity. In most cases, disease is primarily cutaneous, and further clinical evaluation is therefore rarely pursued. We have identified subjects with a novel DOK featuring erythrokeratodermia and initially-asymptomatic, progressive, potentially fatal cardiomyopathy, a finding not previously associated with erythrokeratodermia. We show that de novo missense mutations clustered tightly within a single spectrin repeat of DSP cause this novel cardio-cutaneous disorder, which we term erythrokeratodermia-cardiomyopathy (EKC) syndrome. We demonstrate that DSP mutations in our EKC syndrome subjects affect localization of desmosomal proteins and connexin 43 in the skin, and result in desmosome aggregation, widening of intercellular spaces, and lipid secretory defects. DSP encodes desmoplakin, a primary component of desmosomes, intercellular adhesion junctions most abundant in the epidermis and heart. Though mutations in DSP are known to cause other disorders, our cohort features the unique clinical finding of severe whole-body erythrokeratodermia, with distinct effects on localization of desmosomal proteins and connexin 43. These findings add a severe, previously undescribed syndrome featuring erythrokeratodermia and cardiomyopathy to the spectrum of disease caused by mutation in DSP, and identify a specific region of the protein critical to the pathobiology of EKC syndrome and to DSP function in the heart and skin. PMID:26604139

  18. Expression and in vitro regulation of integrins by normal human urothelial cells.

    PubMed

    Southgate, J; Kennedy, W; Hutton, K A; Trejdosiewicz, L K

    1995-08-01

    Integrins are thought to be essential adhesion receptors for the maintenance of tissue histioarchitecture. The purpose of this study was to determine integrin expression patterns in the human stratified transitional epithelium of the urinary tract (urothelium). In situ expression patterns were compared with in vitro expression, using a normal cell culture model system in which the effects of cell stratification can be studied independently of differentiation. By immunohistological criteria, the urothelia of bladder, ureter and renal pelvis expressed alpha 2 beta 1 and alpha 3 beta 1 integrins in all layers at intercellular junctions, and cytoplasmically in the lower strata. By contrast, alpha 6 beta 4 and occasionally alpha v beta 4 were expressed only by basal cells and localised to the basal lamina. These expression patterns were unaltered in specimens where an inflammatory cell infiltrate was present. In long-term cultures of normal urothelial cells maintained in a low-Ca++ serum-free medium, the monolayer cultures expressed alpha 2 beta 1, alpha 3 beta 1 and alpha 5 beta 1 integrins at intercellular junctions and in cytoplasmic inclusions, whereas alpha 6 beta 4 was distributed in a random pattern over the substratum. Increasing exogenous Ca++ concentrations induced cell stratification and desmosome formation, but not cytodifferentiation. Under these conditions, alpha 6 beta 4 became cell-, rather than substratum-associated, localising particularly to filopodia and lamellipodia. Quantitation of integrin expression by flow cytometry confirmed increased surface expression of alpha 6 beta 4 in high Ca++ media, and also of alpha 3 and alpha 5, but not alpha 2, subunits. These results suggest that alpha 2 beta 1 and alpha 3 beta 1 integrins, although differentially regulated, are mainly involved in homotypic cell-cell interactions and the maintenance of a stratified morphology, whereas alpha 6 beta 4 is the principal integrin involved in substratum adhesion.

  19. Effect of nuclear factor kappa B on intercellular adhesion molecule-1 expression and neutrophil infiltration in lung injury induced by intestinal ischemia/reperfusion in rats

    PubMed Central

    Tian, Xiao-Feng; Yao, Ji-Hong; Li, Ying-Hua; Zhang, Xue-Song; Feng, Bing-An; Yang, Chun-Ming; Zheng, Shu-Sen

    2006-01-01

    AIM: To investigate the role of nuclear factor kappa B (NF-κB) in the pathogenesis of lung injury induced by intestinal ischemia/reperfusion (I/R), and its effect on intercellular adhesion molecule-1 (ICAM-1) expression and neutrophil infiltration. METHODS: Twenty-four Wistar rats were divided randomly into control, I/R and pyrrolidine dithiocarbamate (PDTC) treatment groups, n = 8 in each. I/R group and PDTC treatment group received superior mysenteric artery (SMA) occluding for 1 h and reperfusion for 2 h. PDTC group was administrated with intraperitoneal injection of 2% 100 mg/kg PDTC 1 h before surgery. Lung histology and bronchia alveolus lung fluid (BALF) protein were assayed. Serum IL-6, lung malondialdehyde (MDA) and myeloperoxidase (MPO) as well as the expression level of NF-κB and ICAM-1 were measured. RESULTS: Lung injury induced by intestinal I/R, was characterized by edema, hemorrhage and neutrophil infiltration as well as by the significant rising of BALF protein. Compared to control group, the levels of serum IL-6 and lung MDA and MPO increased significantly in I/R group (P = 0.001). Strong positive expression of NF-κB p65 and ICAM-1 was observed. After the administration of PDTC, the level of serum IL-6, lung MDA and MPO as well as NF-κB and ICAM-1 decreased significantly (P < 0.05) when compared to I/R group. CONCLUSION: The activation of NF-κB plays an important role in the pathogenesis of lung injury induced by intestinal I/R through upregulating the neutrophil infiltration and lung ICAM-1 expression. PDTC as an inhibitor of NF-κB can prevent lung injury induced by intestinal I/R through inhibiting the activity of NF-κB. PMID:16489637

  20. Impact of Intercellular Adhesion Molecule-1 Genetic Polymorphisms on Coronary Artery Disease Susceptibility in Taiwanese Subjects.

    PubMed

    Chou, Chi-Hung; Ueng, Kwo-Chang; Liu, Yu-Fan; Wu, Chih-Hsien; Yang, Shun-Fa; Wang, Po-Hui

    2015-01-01

    The principal pathogenesis of coronary artery disease (CAD) is coronary artery atherosclerosis, a chronic inflammatory disease of the vessel walls of the coronary artery. Intercellular adhesion molecule-1 (ICAM-1) displays an important role in the development of the inflammation reaction and atherosclerosis. Few studies report the association of ICAM-1 genetic polymorphisms with CAD in Taiwanese subjects. Therefore, we conducted a study to associate the single nucleotide polymorphisms (SNPs) of ICAM-1, rs5491, rs5498, rs281432 and rs3093030 with CAD. Five hundred and twenty-five male and female subjects, who received elective coronary angiography in Taiwan Chung Shan Medical University Hospital, were recruited to determine four ICAM-1 SNPs by real time-polymerase chain reaction and genotyping. The relationships among ICAM-1 SNPs, haplotypes, demographic and characteristics and CAD were analyzed. This study showed that rs281432 (C8823G) was the only ICAM-1 SNP which affect the development of CAD. Multivariate analysis revealed that ICAM-1 SNP rs281432 CC/CG [p=0.016; odds ratio (OR): 2.56, 95% confidence interval (CI): 1.19-5.56], male gender (p=0.018; OR: 1.66, 95% CI: 1.09-2.51), aspirin use in the past 7 days (p=0.001; OR: 2.05, 95% CI: 1.33-3.14), hypertension (p<0.001; OR: 2.15, 95% CI: 1.42-3.25), serum cardiac troponin I elevation (p<0.001; OR: 2.14, 95% CI: 1.47-3.24) and severe angina in recent 24 hours (p=0.001; OR: 1.97, 95% CI: 1.31- 2.95) increase the risk of CAD. In conclusion, ICAM-1 SNP rs281432 is an independent factor to predict the development of CAD. ICAM-1 SNP rs281432 homozygotic mutant GG can reduce the susceptibility to the CAD in Taiwanese subjects.

  1. Nifedipine inhibits advanced glycation end products (AGEs) and their receptor (RAGE) interaction-mediated proximal tubular cell injury via peroxisome proliferator-activated receptor-gamma activation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Matsui, Takanori; Yamagishi, Sho-ichi, E-mail: shoichi@med.kurume-u.ac.jp; Takeuchi, Masayoshi

    2010-07-23

    Research highlights: {yields} Nifedipine inhibited the AGE-induced up-regulation of RAGE mRNA levels in tubular cells, which was prevented by GW9662, an inhibitor of peroxisome proliferator-activated receptor-{gamma}. {yields} GW9662 treatment alone increased RAGE mRNA levels in tubular cells. {yields} Nifedipine inhibited the AGE-induced reactive oxygen species generation, NF-{kappa}B activation and increases in intercellular adhesion molecule-1 and transforming growth factor-{beta} gene expression in tubular cells, all of which were blocked by GW9662. -- Abstract: There is a growing body of evidence that advanced glycation end products (AGEs) and their receptor (RAGE) interaction evokes oxidative stress generation and subsequently elicits inflammatory and fibrogenicmore » reactions, thereby contributing to the development and progression of diabetic nephropathy. We have previously found that nifedipine, a calcium-channel blocker (CCB), inhibits the AGE-induced mesangial cell damage in vitro. However, effects of nifedipine on proximal tubular cell injury remain unknown. We examined here whether and how nifedipine blocked the AGE-induced tubular cell damage. Nifedipine, but not amlodipine, a control CCB, inhibited the AGE-induced up-regulation of RAGE mRNA levels in tubular cells, which was prevented by the simultaneous treatment of GW9662, an inhibitor of peroxisome proliferator-activated receptor-{gamma} (PPAR{gamma}). GW9662 treatment alone was found to increase RAGE mRNA levels in tubular cells. Further, nifedipine inhibited the AGE-induced reactive oxygen species generation, NF-{kappa}B activation and increases in intercellular adhesion molecule-1 and transforming growth factor-beta gene expression in tubular cells, all of which were blocked by GW9662. Our present study provides a unique beneficial aspect of nifedipine on diabetic nephropathy; it could work as an anti-oxidative and anti-inflammatory agent against AGEs in tubular cells by suppressing RAGE expression via PPAR{gamma} activation.« less

  2. High-polyphenol chocolate reduces endothelial dysfunction and oxidative stress during acute transient hyperglycaemia in Type 2 diabetes: a pilot randomized controlled trial.

    PubMed

    Mellor, D D; Madden, L A; Smith, K A; Kilpatrick, E S; Atkin, S L

    2013-04-01

    To investigate the effects of high-polyphenol chocolate upon endothelial function and oxidative stress in Type 2 diabetes mellitus during acute transient hyperglycaemia induced following a 75-g oral glucose challenge. Ten subjects with Type 2 diabetes underwent a double-blinded randomized controlled crossover study. A 75-g oral glucose load was used to induce hyperglycaemia, which was administered to participants 60 min after they had ingested either low (control) or high-polyphenol chocolate. Participants undertook testing at weekly intervals, following an initial cocoa-free period. Endothelial function was assessed by both functional [reactive hyperaemia peripheral artery tonometry (EndoPAT-2000) and serum markers (including intercellular adhesion molecule 1, P-selectin and P-selectin glycoprotein ligand 1]. Urinary 15-F2t-isoprostane adjusted for creatinine was used as an oxidative stress marker. Measurements were made at baseline and 2 h post-ingestion of the glucose load. Prior consumption of high-polyphenol chocolate before a glucose load improved endothelial function (1.7 ± 0.1 vs. 2.3 ± 0.1%, P = 0.01), whereas prior consumption of control chocolate resulted in a significant increase in intercellular adhesion molecule 1 (321.1 ± 7.6 vs. 373.6 ± 10.5 ng/ml, P = 0.04) and 15-F2t-isoprostane (116.8 ± 5.7 vs. 207.1 ± 5.7 mg/mol, P = 0.02). Analysis of percentage changes from baseline comparing control and high-polyphenol chocolate showed a significant improvement for high-polyphenol chocolate in both measures of endothelial function (P < 0.05) and for urinary 15-F2t-isoprostane (P = 0.04). High-polyphenol chocolate protected against acute hyperglycaemia-induced endothelial dysfunction and oxidative stress in individuals with Type 2 diabetes mellitus. © 2012 The Authors. Diabetic Medicine © 2012 Diabetes UK.

  3. Intercellular Adhesion Molecule 1 Knockout Abrogates Radiation Induced Pulmonary Inflammation

    NASA Astrophysics Data System (ADS)

    Hallahan, Dennis E.; Virudachalam, Subbulakshmi

    1997-06-01

    Increased expression of intercellular adhesion molecule 1 (ICAM-1; CD54) is induced by exposure to ionizing radiation. The lung was used as a model to study the role of ICAM-1 in the pathogenesis of the radiation-induced inflammation-like response. ICAM-1 expression increased in the pulmonary microvascular endothelium and not in the endothelium of larger pulmonary vessels following treatment of mice with thoracic irradiation. To quantify radiation-induced ICAM-1 expression, we utilized fluorescence-activated cell sorting analysis of anti-ICAM-1 antibody labeling of pulmonary microvascular endothelial cells from human cadaver donors (HMVEC-L cells). Fluorochrome conjugates and UV microscopy were used to quantify the fluorescence intensity of ICAM in the irradiated lung. These studies showed a dose- and time-dependent increase in ICAM-1 expression in the pulmonary microvascular endothelium. Peak expression occurred at 24 h, while threshold dose was as low as 2 Gy. To determine whether ICAM-1 is required for inflammatory cell infiltration into the irradiated lung, the anti-ICAM-1 blocking antibody was administered by tail vein injection to mice following thoracic irradiation. Inflammatory cells were quantified by immunofluorescence for leukocyte common antigen (CD45). Mice treated with the anti-ICAM-1 blocking antibody showed attenuation of inflammatory cell infiltration into the lung in response to ionizing radiation exposure. To verify the requirement of ICAM-1 in the inflammation-like radiation response, we utilized the ICAM-1 knockout mouse. ICAM-1 was not expressed in the lungs of ICAM-1-deficient mice following treatment with thoracic irradiation. ICAM-1 knockout mice had no increase in the inflammatory cell infiltration into the lung in response to thoracic irradiation. These studies demonstrate a radiation dose-dependent increase in ICAM-1 expression in the pulmonary microvascular endothelium, and show that ICAM-1 is required for inflammatory cell infiltration into the irradiated lung.

  4. In vitro studies of the antirhinovirus activity of soluble intercellular adhesion molecule-1.

    PubMed Central

    Arruda, E; Crump, C E; Marlin, S D; Merluzzi, V J; Hayden, F G

    1992-01-01

    We studied the in vitro antirhinovirus activity of a soluble form of intercellular adhesion molecule-1 (sICAM-1). sICAM-1 inhibited the cytopathic effect of 10 representative human rhinovirus (HRV) serotypes of the major receptor group with, 50% effective concentrations (EC50s) of 0.1 to 7.9 micrograms/ml. Cell type-dependent variation in the inhibitory activity of sICAM-1 was observed for two major receptor group serotypes in HeLa cells (EC50, greater than 32 micrograms/ml), and no inhibitory effect was observed for two serotypes which use different cell receptors. Yield reduction assays showed that sICAM-1 inhibited the replication of HRV serotype 39 (HRV-39) in human adenoid explants in a concentration-dependent manner. No direct inactivation of infectivity of HRV-39 (EC50, 0.5 microgram/ml) was observed after incubation with sICAM-1 (32 micrograms/ml) for up to 24 h. Single-cycle-of-replication experiments with the addition of sICAM-1 at 10 micrograms/ml at different times showed that the inhibitory effect occurs only when sICAM-1 is added within 30 min after infection. In experiments in which absorption was carried out at 4 degrees C and then a single cycle of replication incubation was carried out at 33 degrees C, it was found that sICAM-1 at 10 micrograms/ml was inhibitory only when it was present during the absorption period. Our data show that sICAM-1 is inhibitory for representative major receptor group serotypes of HRV in two cell lines and human respiratory epithelium, that the interaction of sICAM-1 with HRV is readily reversible by dilution, and that the inhibitory effect of sICAM-1 on virus replication is present early in the infection cycle. PMID:1358025

  5. Effects of anisodamine on the expressions of vascular endothelial growth factor and intercellular adhesion molecule 1 in experimental infusion phlebitis.

    PubMed

    Zhang, Zhen-Xiang; Wang, Peng; Zhang, Qiu-Shi; Pan, Xue; Zhao, Qing-Xia; Wang, Xiao-Kai

    2012-01-01

    Infusion phlebitis is the most common side effect of clinical intravenous drug therapy and several clinical studies have demonstrated that anisodamine can effectively prevent the occurrence of infusion phlebitis. This study was designed to investigate effects of anisodamine on the expressions of vascular endothelial growth factor (VEGF) and intercellular adhesion molecule 1 (ICAM-1) in a rabbit model of infusion phlebitis and to analyze the mechanisms of anisodamine effect on the prevention and treatment of experimental infusion phlebitis. Twenty-four specific pathogen-free male Japanese white rabbits were randomly assigned to the control group, the model group, the magnesium sulfate group and the anisodamine group. The rabbit model of infusion phlebitis, induced by intravenous administration, was established and expressions of VEGF and ICAM-1 were determined and contrasted with the control group treated with normal saline. We evaluated expression by histopathology, immunohistochemistry, reverse transcription-polymerase chain reaction, and Western blotting assay. Pathohistological changes of the model group were observed, such as loss of venous endothelial cells, inflammatory cell infiltration, edema and thrombus. The magnesium sulfate group and the anisodamine group showed significant protective effects on vascular congestion, inflammatory cell infiltration, proliferation, swelling of endothelium and perivascular hemorrhage. The model group showed the highest expressions of VEGF and ICAM-1 of the four groups (P < 0.01). On the contrary, anisodamine alleviated the inflammatory damage by significantly reducing the expressions of VEGF and ICAM-1 compared with the model group (P < 0.01). There was no significant difference in the expressions of VEGF and ICAM-1 between the magnesium sulfate group and the anisodamine group (P > 0.05). Anisodamine alleviates inflammatory damage by significantly reducing the expressions of VEGF and ICAM-1, and shows significant protective effects in an animal model of infusion phlebitis.

  6. Combined Treatment with Amlodipine and Atorvastatin Calcium Reduces Circulating Levels of Intercellular Adhesion Molecule-1 and Tumor Necrosis Factor-α in Hypertensive Patients with Prediabetes.

    PubMed

    Huang, Zhouqing; Chen, Chen; Li, Sheng; Kong, Fanqi; Shan, Peiren; Huang, Weijian

    2016-01-01

    To assess the effect of amlodipine and atorvastatin on intercellular adhesion molecule (ICAM)-1 and tumor necrosis factor (TNF)-α expression, as endothelial function and inflammation indicators, respectively, in hypertensive patients with and without prediabetes. Forty-five consecutive patients with hypertension, diagnosed according to JNC7, were divided into two groups based on the presence (HD group, n = 23) or absence (H group, n = 22) of prediabetes, diagnosed according to 2010 ADA criteria, including impaired glucose tolerance (IGT) and fasting glucose tests. All patients simultaneously underwent 12-week treatment with daily single-pill amlodipine besylate/atorvastatin calcium combination (5/10 mg; Hisun-Pfizer Pharmaceuticals Co. Ltd). Serum isolated before and after treatment from overnight fasting blood samples was analyzed by ELISA. In the HD and H groups after vs. before 12-week amlodipine/atorvastatin treatment, there were significantly (all P < 0.01) lower levels of ICAM-1 (3.06 ± 0.34 vs. 4.07 ± 0.70 pg/ml; 3.26 ± 0.32 vs. 3.81 ± 0.60 pg/ml, respectively) and TNF-α (78.71 ± 9.19 vs. 110.94 ± 10.71 pg/ml; 80.95 ± 9.33 vs. 101.79 ± 11.72 pg/ml, respectively), with more pronounced reductions in HD vs. H group (ICAM-1Δ: 1.01 ± 0.80 vs. 0.55 ± 0.64 pg/ml, respectively, P = 0.037; TNF-αΔ: 32.23 ± 14.33 vs. 20.84 ± 14.89 pg/ml, respectively, P = 0.011), independent of the blood pressure (BP) and cholesterol level reduction. Amlodipine/atorvastatin improved endothelial function and inflammation, as reflected by lower circulating levels of ICAM-1 and TNF-α, more prominently in hypertensives with than without prediabetes. Starting statin treatment before overt diabetes in hypertensives might thus improve cardiovascular outcomes.

  7. Genetic, epigenetic and protein analyses of intercellular adhesion molecule 1 in Malaysian subjects with type 2 diabetes and diabetic nephropathy.

    PubMed

    Abu Seman, Norhashimah; Anderstam, Björn; Wan Mohamud, Wan Nazaimoon; Östenson, Claes-Göran; Brismar, Kerstin; Gu, Harvest F

    2015-01-01

    Recent research has implicated that the inflammation may be a key pathophysiological mechanism in diabetic nephropathy (DN). Intercellular adhesion molecule 1 (ICAM-1) is an acute phase marker of inflammation. In the present study, we carried out genetic, epigenetic and protein analyses of ICAM-1 in a Malaysian population, including normal glucose tolerance (NGT) subjects and type 2 diabetes (T2D) patients with or without DN in order to evaluate its role in DN. Analyses of DNA polymorphism and methylation in the ICAM1 gene were performed with TaqMan allelic discrimination and pyrosequencing, respectively. Plasma ICAM-1 levels were determined using an enzyme-linked immune-sorbent assay kit. We found that the ICAM1 K469E(A/G) polymorphism (rs5498) was significantly associated with DN. Particularly, 86.1% of T2D patients with DN carried heterozygous genotype compared to the patients without DN (68.6%). Furthermore, plasma ICAM-1 levels were increased from NGT subjects to T2D patients without and with DN (P<0.001). The NGT subjects carrying heterozygous genotype had significantly lower plasma ICAM-1 levels compared to the K469(A/A) genotype carriers (P=0.009). In the ICAM1 gene promoter, DNA methylation levels of CpG sites were low, and no association of the ICAM1 DNA methylation alteration with DN was detected. The present study provided evidence that the ICAM1 K469E(A/G) polymorphism with high heterozygous index and elevation of plasma ICAM-1 levels were associated with DN in a Malaysian population. Further prospective study of ICAM-1 protein according to the ICAM1 K469E(A/G) genotypes is necessary for predicting the susceptibility to T2D and DN. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Inactivated Sendai virus particle upregulates cancer cell expression of intercellular adhesion molecule-1 and enhances natural killer cell sensitivity on cancer cells.

    PubMed

    Li, Simin; Nishikawa, Tomoyuki; Kaneda, Yasufumi

    2017-12-01

    We have already reported that the inactivated Sendai virus (hemagglutinating virus of Japan; HVJ) envelope (HVJ-E) has multiple anticancer effects, including induction of cancer-selective cell death and activation of anticancer immunity. The HVJ-E stimulates dendritic cells to produce cytokines and chemokines such as β-interferon, interleukin-6, chemokine (C-C motif) ligand 5, and chemokine (C-X-C motif) ligand 10, which activate both CD8 + T cells and natural killer (NK) cells and recruit them to the tumor microenvironment. However, the effect of HVJ-E on modulating the sensitivity of cancer cells to immune cell attack has yet to be investigated. In this study, we found that HVJ-E induced the production of intercellular adhesion molecule-1 (ICAM-1, CD54), a ligand of lymphocyte function-associated antigen 1, in several cancer cell lines through the activation of nuclear factor-κB downstream of retinoic acid-inducible gene I and the mitochondrial antiviral signaling pathway. The upregulation of ICAM-1 on the surface of cancer cells increased the sensitivity of cancer cells to NK cells. Knocking out expression of ICAM-1 in MDA-MB-231 cells using the CRISPR/Cas9 method significantly reduced the killing effect of NK cells on ICAM-1-depleted MDA-MB-231 cells. In addition, HVJ-E suppressed tumor growth in MDA-MB-231 tumor-bearing SCID mice, and the HVJ-E antitumor effect was impaired when NK cells were depleted by treatment with the anti-asialo GM1 antibody. Our findings suggest that HVJ-E enhances NK cell sensitivity against cancer cells by increasing ICAM-1 expression on the cancer cell surface. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  9. Successful treatment of alopecia areata-like hair loss with the contact sensitizer squaric acid dibutylester (SADBE) in C3H/HeJ mice.

    PubMed

    Freyschmidt-Paul, P; Sundberg, J P; Happle, R; McElwee, K J; Metz, S; Boggess, D; Hoffmann, R

    1999-07-01

    A type of hair loss closely resembling human alopecia areata has been described in C3H/HeJ mice. In order to test the assumed analogy with human alopecia areata, we investigated the efficacy of treatment with the contact allergen squaric acid dibutylester. In 12 C3H/HeJ mice with alopecia areata an allergic contact dermatitis was induced and elicited weekly on one side of the back by topical applications of squaric acid dibutylester. Overt hair regrowth was observed only on the treated side of the back in nine of 12 mice. Histopathologic examination revealed a change in the distribution of the inflammatory infiltrate from a dense perifollicular lymphocytic infiltrate around the mid and lower regions of hair follicles in untreated skin to a uniform presence in the upper dermis in treated skin. Immunohistomorphometric studies revealed that treatment with squaric acid dibutylester increased the CD4+/CD8+ ratio from approximately 1:2 in untreated alopecia areata to 1:1 in treated alopecia areata. Additional immunohistochemical investigations showed an aberrant expression of major histocompatibility complex class I, major histocompatibility complex class II and intercellular adhesion molecule 1 on keratinocytes of the mid and lower parts of hair follicles in untreated alopecia areata. In successfully treated skin ectopic major histocompatibility complex class I and II expression was clearly reduced, whereas intercellular adhesion molecule 1 expression showed only minor changes. In conclusion, alopecia areata-like hair loss in C3H/HeJ mice responded to treatment with the contact sensitizer squaric acid dibutylester analogous to human alopecia areata. Moreover, successful treatment changes the aberrant expression of major histocompatibility complex class I and II in a way similar to that observed in human alopecia areata. These observations support the concept that alopecia areata-like hair loss in C3H/HeJ mice can be utilized as an appropriate model for the study of human alopecia areata.

  10. Effect of Combined Treatment With Folic Acid, Vitamin B6, and Vitamin B12 on Plasma Biomarkers of Inflammation and Endothelial Dysfunction in Women.

    PubMed

    Christen, William G; Cook, Nancy R; Van Denburgh, Martin; Zaharris, Elaine; Albert, Christine M; Manson, JoAnn E

    2018-05-18

    The aim of this study was to determine whether reducing plasma homocysteine concentrations with long-term, combined treatment with folic acid, vitamin B 6 , and vitamin B 12 alters plasma biomarkers of inflammation and endothelial dysfunction in women at increased risk of cardiovascular disease. We conducted a blood substudy of 300 treatment-adherent participants (150 in the active treatment group, 150 in the placebo group) in the WAFACS (Women's Antioxidant and Folic Acid Cardiovascular Study), a randomized, double-blind, placebo-controlled trial testing a daily combination of folic acid (2.5 mg), vitamin B 6 (50 mg), vitamin B 12 (1 mg), or matching placebo, in cardiovascular disease prevention among women at increased risk of cardiovascular disease. Plasma concentration of 3 biomarkers of inflammation (C-reactive protein, interleukin-6, and fibrinogen) and a biomarker of endothelial dysfunction (intercellular adhesion molecule 1) were measured at baseline and at the end of treatment and follow-up. After 7.3 years of combined treatment with folic acid, vitamin B 6 , and vitamin B 12 , homocysteine concentrations were reduced by 18% in the active treatment group as compared with the placebo group ( P <0.001). However, there was no difference between treatment groups in change in blood concentration from baseline to follow-up for C-reactive protein ( P =0.77), interleukin-6 ( P =0.91), intercellular adhesion molecule 1 ( P =0.38), or fibrinogen ( P =0.68). These findings indicate that long-term, combined treatment with folic acid, vitamin B 6 , and vitamin B 12 lowers homocysteine concentrations, but does not alter major biomarkers of vascular inflammation, consistent with the lack of clinical cardiovascular disease benefit in the trial. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000541. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  11. Suppression of E-cadherin function drives the early stages of Ras-induced squamous cell carcinoma through up-regulation of FAK and Src

    PubMed Central

    Alt-Holland, Addy; Sowalsky, Adam; Szwec-Levin, Yonit; Shamis, Yulia; Hatch, Harold; Feig, Larry A.; Garlick, Jonathan A.

    2011-01-01

    Advanced stages of epithelial carcinogenesis involve the loss of intercellular adhesion, but it remains unclear how proteins that regulate alterations in cell-cell and cell-matrix adhesion are deregulated to promote the early stages of cancer development. To address this, a three-dimensional human tissue model that mimics the incipient stages of Squamous Cell Carcinoma (SCC) was used to study how E-cadherin suppression promotes tumor progression in Ras-expressing human keratinocytes. We found that E-cadherin suppression triggered elevated mRNA and protein expression levels of Focal Adhesion Kinase (FAK), and increased FAK and Src activities above the level seen in Ras-expressing E-cadherin-competent keratinocytes. sh-RNA-mediated depletion of FAK and Src restored E-cadherin expression levels by increasing its stability in the membrane, and blocked tumor cell invasion in tissues. Surface transplantation of these tissues to mice resulted in reversion of the tumor phenotype to low-grade tumor islands in contrast to control tissues that manifested an aggressive, high-grade SCC. These findings suggest that the tumor-promoting effect of E-cadherin suppression, a common event in SCC development, is exacerbated by enhanced E-cadherin degradation induced by elevated FAK and Src activities. Furthermore, they imply that targeting FAK or Src in human epithelial cells with neoplastic potential may inhibit the early stages of SCC. PMID:21716326

  12. Effects of cryopreservation on excretory function, cellular adhesion molecules and vessel lumen formation in human umbilical vein endothelial cells.

    PubMed

    Cai, Guoping; Lai, Binbin; Hong, Huaxing; Lin, Peng; Chen, Weifu; Zhu, Zhong; Chen, Haixiao

    2017-07-01

    Cryopreservation is widely used in regenerative medicine for tissue preservation. In the present study, the effects of cryopreservation on excretory function, cellular adhesion molecules and vessel lumen formation in human umbilical vein endothelial cells (HUVECs) were investigated. After 0, 4, 8, 12 or 24 weeks of cryopreservation in liquid nitrogen, the HUVECs were thawed. The excretory functions markers (endothelin‑1, prostaglandin E1, von Willebrand factor and nitric oxide) of HUVECs were measured by ELISA assay. The expression of intercellular adhesion molecule‑1 (ICAM‑1) in HUVECs was analyzed using flow cytometry. An angiogenesis assay was used to determine the angiogeneic capabilities of the thawed HUVECs. The results demonstrated that cryopreserved/thawed and recultivated HUVECs were unsuitable for tissue‑engineered microvascular construction. Specifically, the excretory function of the cells was significantly decreased in the post‑cryopreserved HUVECs at 24 weeks. In addition, the level of ICAM‑1 in HUVECs was significantly upregulated from the fourth week of cryopreservation. Furthermore, the tube‑like structure‑forming potential was weakened with increasing cryopreservation duration, and the numbers of lumen and the length of the pipeline were decreased in the thawed HUVECs, in a time‑dependent manner. In conclusion, the results of the present study revealed that prolonged cryopreservation may lead to HUVEC dysfunction and did not create stable cell lines for tissue‑engineered microvascular construction.

  13. Cortactin deficiency is associated with reduced neutrophil recruitment but increased vascular permeability in vivo.

    PubMed

    Schnoor, Michael; Lai, Frank P L; Zarbock, Alexander; Kläver, Ruth; Polaschegg, Christian; Schulte, Dörte; Weich, Herbert A; Oelkers, J Margit; Rottner, Klemens; Vestweber, Dietmar

    2011-08-01

    Neutrophil extravasation and the regulation of vascular permeability require dynamic actin rearrangements in the endothelium. In this study, we analyzed in vivo whether these processes require the function of the actin nucleation-promoting factor cortactin. Basal vascular permeability for high molecular weight substances was enhanced in cortactin-deficient mice. Despite this leakiness, neutrophil extravasation in the tumor necrosis factor-stimulated cremaster was inhibited by the loss of cortactin. The permeability defect was caused by reduced levels of activated Rap1 (Ras-related protein 1) in endothelial cells and could be rescued by activating Rap1 via the guanosine triphosphatase (GTPase) exchange factor EPAC (exchange protein directly activated by cAMP). The defect in neutrophil extravasation was caused by enhanced rolling velocity and reduced adhesion in postcapillary venules. Impaired rolling interactions were linked to contributions of β(2)-integrin ligands, and firm adhesion was compromised by reduced ICAM-1 (intercellular adhesion molecule 1) clustering around neutrophils. A signaling process known to be critical for the formation of ICAM-1-enriched contact areas and for transendothelial migration, the ICAM-1-mediated activation of the GTPase RhoG was blocked in cortactin-deficient endothelial cells. Our results represent the first physiological evidence that cortactin is crucial for orchestrating the molecular events leading to proper endothelial barrier function and leukocyte recruitment in vivo.

  14. Inhibitory Effect of a French Maritime Pine Bark Extract-Based Nutritional Supplement on TNF-α-Induced Inflammation and Oxidative Stress in Human Coronary Artery Endothelial Cells

    PubMed Central

    McGrath, Kristine C. Y.; Li, Xiao-Hong; McRobb, Lucinda S.; Heather, Alison K.

    2015-01-01

    Oxidative stress and inflammation, leading to endothelial dysfunction, contribute to the pathogenesis of atherosclerosis. The popularity of natural product supplements has increased in recent years, especially those with purported anti-inflammatory and/or antioxidant effects. The efficacy and mechanism of many of these products are not yet well understood. In this study, we tested the antioxidant and anti-inflammatory effects of a supplement, HIPER Health Supplement (HIPER), on cytokine-induced inflammation and oxidative stress in human coronary artery endothelial cells (HCAECs). HIPER is a mixture of French maritime pine bark extract (PBE), honey, aloe vera, and papaya extract. Treatment for 24 hours with HIPER reduced TNF-α-induced reactive oxygen species (ROS) generation that was associated with decreased NADPH oxidase 4 and increased superoxide dismutase-1 expression. HIPER inhibited TNF-α induced monocyte adhesion to HCAECs that was in keeping with decreased expression of vascular cell adhesion molecule-1 and intercellular cell adhesion molecule-1 and decreased nuclear factor-kappa B (NF-κB) activation. Further investigation of mechanism showed HIPER reduced TNF-α induced IκBα and p38 and MEK1/2 MAP kinases phosphorylation. Our findings show that HIPER has potent inhibitory effects on HCAECs inflammatory and oxidative stress responses that may protect against endothelial dysfunction that underlies early atherosclerotic lesion formation. PMID:26664450

  15. Soluble Forms of Intercellular and Vascular Cell Adhesion Molecules Independently Predict Progression to Type 2 Diabetes in Mexican American Families

    PubMed Central

    Kulkarni, Hemant; Mamtani, Manju; Peralta, Juan; Almeida, Marcio; Dyer, Thomas D.; Goring, Harald H.; Johnson, Matthew P.; Duggirala, Ravindranath; Mahaney, Michael C.; Olvera, Rene L.; Almasy, Laura; Glahn, David C.; Williams-Blangero, Sarah; Curran, Joanne E.; Blangero, John

    2016-01-01

    Objective While the role of type 2 diabetes (T2D) in inducing endothelial dysfunction is fairly well-established the etiological role of endothelial dysfunction in the onset of T2D is still a matter of debate. In the light of conflicting evidence in this regard, we conducted a prospective study to determine the association of circulating levels of soluble intercellular adhesion molecule 1 (sICAM-1) and soluble vessel cell adhesion molecule 1 (sVCAM-1) with incident T2D. Methods Data from this study came from 1,269 Mexican Americans of whom 821 initially T2D-free individuals were longitudinally followed up in the San Antonio Family Heart Study. These individuals were followed for 9752.95 person-years for development of T2D. Prospective association of sICAM-1 and sVCAM-1 with incident T2D was studied using Kaplan-Meier survival plots and mixed effects Cox proportional hazards modeling to account for relatedness among study participants. Incremental value of adhesion molecule biomarkers was studied using integrated discrimination improvement (IDI) and net reclassification improvement (NRI) indexes. Results Decreasing median values for serum concentrations of sICAM-1 and sVCAM-1 were observed in the following groups in this order: individuals with T2D at baseline, individuals who developed T2D during follow-up, individuals with prediabetes at baseline and normal glucose tolerant (NGT) individuals who remained T2D-free during follow-up. Top quartiles for sICAM-1 and sVCAM-1 were strongly and significantly associated with homeostatic model of assessment—insulin resistance (HOMA-IR). Mixed effects Cox proportional hazards modeling revealed that after correcting for important clinical confounders, high sICAM-1 and sVCAM-1 concentrations were associated with 2.52 and 1.99 times faster progression to T2D as compared to low concentrations, respectively. Individuals with high concentrations for both sICAM-1 and sVCAM-1 progressed to T2D 3.42 times faster than those with low values for both sICAM-1 and sVCAM-1. The results were similar in women in reproductive age group and the remainder of the cohort. Inclusion of sICAM-1 and sVCAM-1 in predictive models significantly improved reclassification and discrimination. The majority of these results were seen even when the analyses were restricted to NGT individuals. Conclusion Serum concentrations of sICAM-1 and sVCAM-1 independently and additively predict future T2D and represent important candidate biomarkers of T2D. PMID:27007680

  16. Carbon nanotube and nanofiber exposure and sputum and blood biomarkers of early effect among U.S. workers.

    PubMed

    Beard, John D; Erdely, Aaron; Dahm, Matthew M; de Perio, Marie A; Birch, M Eileen; Evans, Douglas E; Fernback, Joseph E; Eye, Tracy; Kodali, Vamsi; Mercer, Robert R; Bertke, Stephen J; Schubauer-Berigan, Mary K

    2018-07-01

    Carbon nanotubes and nanofibers (CNT/F) are increasingly used for diverse applications. Although animal studies suggest CNT/F exposure may cause deleterious health effects, human epidemiological studies have typically been small, confined to single workplaces, and limited in exposure assessment. We conducted an industrywide cross-sectional epidemiological study of 108 workers from 12 U.S. sites to evaluate associations between occupational CNT/F exposure and sputum and blood biomarkers of early effect. We assessed CNT/F exposure via personal breathing zone, filter-based air sampling to measure background-corrected elemental carbon (EC) (a CNT/F marker) mass and microscopy-based CNT/F structure count concentrations. We measured 36 sputum and 37 blood biomarkers. We used factor analyses with varimax rotation to derive factors among sputum and blood biomarkers separately. We used linear, Tobit, and unconditional logistic regression models to adjust for potential confounders and evaluate associations between CNT/F exposure and individual biomarkers and derived factors. We derived three sputum and nine blood biomarker factors that explained 78% and 67%, respectively, of the variation. After adjusting for potential confounders, inhalable EC and total inhalable CNT/F structures were associated with the most sputum and blood biomarkers, respectively. Biomarkers associated with at least three CNT/F metrics were 72 kDa type IV collagenase/matrix metalloproteinase-2 (MMP-2), interleukin-18, glutathione peroxidase (GPx), myeloperoxidase, and superoxide dismutase (SOD) in sputum and MMP-2, matrix metalloproteinase-9, metalloproteinase inhibitor 1/tissue inhibitor of metalloproteinases 1, 8-hydroxy-2'-deoxyguanosine, GPx, SOD, endothelin-1, fibrinogen, intercellular adhesion molecule 1, vascular cell adhesion protein 1, and von Willebrand factor in blood, although directions of associations were not always as expected. Inhalable rather than respirable CNT/F was more consistently associated with fibrosis, inflammation, oxidative stress, and cardiovascular biomarkers. Published by Elsevier Ltd.

  17. Structure and function of gap junction proteins: role of gap junction proteins in embryonic heart development.

    PubMed

    Ahir, Bhavesh K; Pratten, Margaret K

    2014-01-01

    Intercellular (cell-to-cell) communication is a crucial and complex mechanism during embryonic heart development. In the cardiovascular system, the beating of the heart is a dynamic and key regulatory process, which is functionally regulated by the coordinated spread of electrical activity through heart muscle cells. Heart tissues are composed of individual cells, each bearing specialized cell surface membrane structures called gap junctions that permit the intercellular exchange of ions and low molecular weight molecules. Gap junction channels are essential in normal heart function and they assist in the mediated spread of electrical impulses that stimulate synchronized contraction (via an electrical syncytium) of cardiac tissues. This present review describes the current knowledge of gap junction biology. In the first part, we summarise some relevant biochemical and physiological properties of gap junction proteins, including their structure and function. In the second part, we review the current evidence demonstrating the role of gap junction proteins in embryonic development with particular reference to those involved in embryonic heart development. Genetics and transgenic animal studies of gap junction protein function in embryonic heart development are considered and the alteration/disruption of gap junction intercellular communication which may lead to abnormal heart development is also discussed.

  18. A Review of Podocyte Biology.

    PubMed

    Garg, Puneet

    2018-05-31

    Podocyte biology is a developing science that promises to help improve understanding of the mechanistic nature of multiple diseases associated with proteinuria. Proteinuria in nephrotic syndrome has been linked to mechanistic dysfunctions in the renal glomerulus involving the function of podocyte epithelial cells, including podocyte foot process effacement. Developments in imaging technology are improving knowledge of the detailed structure of the human renal glomerulus and cortex. Podocyte foot processes attach themselves to the glomerular capillaries at the glomerular basement membrane (GBM) forming intercellular junctions that form slit diaphragm filtration barriers that help maintain normal renal function. Damage in this area has been implicated in glomerular disease. Injured podocytes undergo effacement whereby they lose their structure and spread out, leading to a reduction in filtration barrier function. Effacement is typically associated with the presence of proteinuria in focal segmental glomerulosclerosis, minimal change disease, and diabetes. It is thought to be due to a breakdown in the actin cytoskeleton of the foot processes, complex contractile apparatuses that allow podocytes to dynamically reorganize according to changes in filtration requirements. The process of podocyte depletion correlates with the development of glomerular sclerosis and chronic kidney disease. Focal adhesion complexes that interact with the underlying GBM bind the podocytes within the glomerular structure and prevent their detachment. Key Messages: Knowledge of glomerular podocyte biology is helping to advance our understanding of the science and mechanics of the glomerular filtering process, opening the way to a variety of new potential applications for clinical targeting. © 2018 S. Karger AG, Basel.

  19. Sooty mangabey genome sequence provides insight into AIDS resistance in a natural SIV host.

    PubMed

    Palesch, David; Bosinger, Steven E; Tharp, Gregory K; Vanderford, Thomas H; Paiardini, Mirko; Chahroudi, Ann; Johnson, Zachary P; Kirchhoff, Frank; Hahn, Beatrice H; Norgren, Robert B; Patel, Nirav B; Sodora, Donald L; Dawoud, Reem A; Stewart, Caro-Beth; Seepo, Sara M; Harris, R Alan; Liu, Yue; Raveendran, Muthuswamy; Han, Yi; English, Adam; Thomas, Gregg W C; Hahn, Matthew W; Pipes, Lenore; Mason, Christopher E; Muzny, Donna M; Gibbs, Richard A; Sauter, Daniel; Worley, Kim; Rogers, Jeffrey; Silvestri, Guido

    2018-01-03

    In contrast to infections with human immunodeficiency virus (HIV) in humans and simian immunodeficiency virus (SIV) in macaques, SIV infection of a natural host, sooty mangabeys (Cercocebus atys), is non-pathogenic despite high viraemia. Here we sequenced and assembled the genome of a captive sooty mangabey. We conducted genome-wide comparative analyses of transcript assemblies from C. atys and AIDS-susceptible species, such as humans and macaques, to identify candidates for host genetic factors that influence susceptibility. We identified several immune-related genes in the genome of C. atys that show substantial sequence divergence from macaques or humans. One of these sequence divergences, a C-terminal frameshift in the toll-like receptor-4 (TLR4) gene of C. atys, is associated with a blunted in vitro response to TLR-4 ligands. In addition, we found a major structural change in exons 3-4 of the immune-regulatory protein intercellular adhesion molecule 2 (ICAM-2); expression of this variant leads to reduced cell surface expression of ICAM-2. These data provide a resource for comparative genomic studies of HIV and/or SIV pathogenesis and may help to elucidate the mechanisms by which SIV-infected sooty mangabeys avoid AIDS.

  20. Sooty mangabey genome sequence provides insight into AIDS resistance in a natural SIV host

    PubMed Central

    Palesch, David; Bosinger, Steven E.; Tharp, Gregory K.; Vanderford, Thomas H.; Paiardini, Mirko; Chahroudi, Ann; Johnson, Zachary P.; Kirchhoff, Frank; Hahn, Beatrice H.; Norgren, Robert B.; Patel, Nirav B.; Sodora, Donald L.; Dawoud, Reem A.; Stewart, Caro-Beth; Seepo, Sara M.; Harris, R. Alan; Liu, Yue; Raveendran, Muthuswamy; Han, Yi; English, Adam; Thomas, Gregg W. C.; Hahn, Matthew W.; Pipes, Lenore; Mason, Christopher E.; Muzny, Donna M.; Gibbs, Richard A.; Sauter, Daniel; Worley, Kim; Rogers, Jeffrey; Silvestri, Guido

    2018-01-01

    In contrast to infections with human immunodeficiency virus (HIV) in humans and simian immunodeficiency virus (SIV) in macaques, SIV infection of a natural host, sooty mangabeys (Cercocebus atys), is non-pathogenic despite high viraemia1. Here we sequenced and assembled the genome of a captive sooty mangabey. We conducted genome-wide comparative analyses of transcript assemblies from C. atys and AIDS-susceptible species, such as humans and macaques, to identify candidates for host genetic factors that influence susceptibility. We identified several immune-related genes in the genome of C. atys that show substantial sequence divergence from macaques or humans. One of these sequence divergences, a C-terminal frameshift in the toll-like receptor-4 (TLR4) gene of C. atys, is associated with a blunted in vitro response to TLR-4 ligands. In addition, we found a major structural change in exons 3–4 of the immune-regulatory protein intercellular adhesion molecule 2 (ICAM-2); expression of this variant leads to reduced cell surface expression of ICAM-2. These data provide a resource for comparative genomic studies of HIV and/or SIV pathogenesis and may help to elucidate the mechanisms by which SIV-infected sooty mangabeys avoid AIDS. PMID:29300007

  1. Effect of fibril shape on adhesive properties

    NASA Astrophysics Data System (ADS)

    Soto, Daniel; Hill, Ginel; Parness, Aaron; Esparza, Noé; Cutkosky, Mark; Kenny, Tom

    2010-08-01

    Research into the gecko's adhesive system revealed a unique architecture for adhesives using tiny hairs. By using a stiff material (β-keratin) to create a highly structured adhesive, the gecko's system demonstrates properties not seen in traditional pressure-sensitive adhesives which use a soft, unstructured planar layer. In contrast to pressure sensitive adhesives, the gecko adhesive displays frictional adhesion, in which increased shear force allows it to withstand higher normal loads. Synthetic fibrillar adhesives have been fabricated but not all demonstrate this frictional adhesion property. Here we report the dual-axis force testing of single silicone rubber pillars from synthetic adhesive arrays. We find that the shape of the adhesive pillar dictates whether frictional adhesion or pressure-sensitive behavior is observed. This work suggests that both types of behavior can be achieved with structures much larger than gecko terminal structures. It also indicates that subtle differences in the shape of these pillars can significantly influence their properties.

  2. The Integrated Role of Wnt/β-Catenin, N-Glycosylation, and E-Cadherin-Mediated Adhesion in Network Dynamics

    PubMed Central

    Vargas, Diego A.; Sun, Meng; Sadykov, Khikmet; Kukuruzinska, Maria A.; Zaman, Muhammad H.

    2016-01-01

    The cellular network composed of the evolutionarily conserved metabolic pathways of protein N-glycosylation, Wnt/β-catenin signaling pathway, and E-cadherin-mediated cell-cell adhesion plays pivotal roles in determining the balance between cell proliferation and intercellular adhesion during development and in maintaining homeostasis in differentiated tissues. These pathways share a highly conserved regulatory molecule, β-catenin, which functions as both a structural component of E-cadherin junctions and as a co-transcriptional activator of the Wnt/β-catenin signaling pathway, whose target is the N-glycosylation-regulating gene, DPAGT1. Whereas these pathways have been studied independently, little is known about the dynamics of their interaction. Here we present the first numerical model of this network in MDCK cells. Since the network comprises a large number of molecules with varying cell context and time-dependent levels of expression, it can give rise to a wide range of plausible cellular states that are difficult to track. Using known kinetic parameters for individual reactions in the component pathways, we have developed a theoretical framework and gained new insights into cellular regulation of the network. Specifically, we developed a mathematical model to quantify the fold-change in concentration of any molecule included in the mathematical representation of the network in response to a simulated activation of the Wnt/ β-catenin pathway with Wnt3a under different conditions. We quantified the importance of protein N-glycosylation and synthesis of the DPAGT1 encoded enzyme, GPT, in determining the abundance of cytoplasmic β-catenin. We confirmed the role of axin in β-catenin degradation. Finally, our data suggest that cell-cell adhesion is insensitive to E-cadherin recycling in the cell. We validate the model by inhibiting β-catenin-mediated activation of DPAGT1 expression and predicting changes in cytoplasmic β-catenin concentration and stability of E-cadherin junctions in response to DPAGT1 inhibition. We show the impact of pathway dysregulation through measurements of cell migration in scratch-wound assays. Collectively, our results highlight the importance of numerical analyses of cellular networks dynamics to gain insights into physiological processes and potential design of therapeutic strategies to prevent epithelial cell invasion in cancer. PMID:27427963

  3. MicroSPECT imaging of triple negative breast cancer cell tumor xenografted in athymic mice with radioiodinated anti-ICAM-1 monoclonal antibody.

    PubMed

    You, Linyi; Wang, Xiangyu; Guo, Zhide; Zhang, Deliang; Zhang, Pu; Li, Jindian; Su, Xinhui; Pan, Weimin; Zhang, Xianzhong

    2018-04-04

    Intercellular adhesion molecule-1(ICAM-1) is a potential molecular target and biomarker for triple negative breast cancer (TNBC) therapy and diagnosis. In this study, aICAM-1 was radioiodinated with 125 I/ 131 I in high radiochemical yield and the probes for TNBC tumor targeting and radioimmunotherapy were evaluated in tumor-bearing mice. High and specific accumulation of 125 I-aICAM1 in TNBC MDA-MB-231 tumor was observed in SPECT imaging and the tumor grew was inhibited obviously by 131 I-aICAM1. Thus, the radioiodinated aICAM1 could serve as potential agents for TNBC theranostics. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Proteome Analyses of Staphylococcus aureus Biofilm at Elevated Levels of NaCl

    PubMed Central

    Islam, Nazrul; Ross, Julia M; Marten, Mark R

    2016-01-01

    Our studies demonstrate that sodium chloride (NaCl) induces changes in biofilm, mediated by increased production of polysaccharides intercellular adhesion (PIA). We identified 12 proteins that showed higher abundance in increased level of NaCl. This includes one important protein (IsaA) known to be associated with biofilm stability. In addition, we also found higher abundance of a cold shock protein, CspA, at higher NaCl. We have also identified several other proteins that are differentially expressed to the elevated levels of NaCl and mapped them in the regulatory pathways of PIA. The majority of proteins are involved with various aspects bacterial metabolic function. Our results demonstrated that NaCl influences gene regulatory networks controlling exopolysaccharide expression. PMID:26973848

  5. The pathogenic relevance of αM-integrin in Guillain-Barré syndrome.

    PubMed

    Dong, Chaoling; Palladino, Steven P; Helton, Eric Scott; Ubogu, Eroboghene E

    2016-11-01

    The molecular determinants and mechanisms involved in leukocyte trafficking across the blood-nerve barrier (BNB) in the acute inflammatory demyelinating polyradiculoneuropathy (AIDP) variant of Guillain-Barré syndrome are incompletely understood. Prior work using a flow-dependent in vitro human BNB model demonstrated a crucial role for α M -integrin (CD11b)-intercellular adhesion molecule-1 interactions in AIDP patient leukocyte trafficking. The aim of this study is to directly investigate the biological relevance of CD11b in AIDP pathogenesis. Immunohistochemistry was performed on three AIDP patient sural nerve biopsies to evaluate endoneurial leukocyte CD11b expression. A severe murine experimental autoimmune neuritis (sm-EAN) model was utilized to determine the functional role of CD11b in leukocyte trafficking in vivo and determine its effect on neurobehavioral measures of disease severity, electrophysiological assessments of axonal integrity and myelination and histopathological measures of peripheral nerve inflammatory demyelination. Time-lapse video microscopy and electron microscopy were employed to observe structural alterations at the BNB during AIDP patient leukocyte trafficking in vitro and in situ, respectively. Large clusters of endoneurial CD11b+ leukocytes associated with demyelinating axons were observed in AIDP patient sural nerves. Leukocyte CD11b expression was upregulated during sm-EAN. 5 mg/kg of a function-neutralizing monoclonal rat anti-mouse CD11b antibody administered after sm-EAN disease onset significantly ameliorated disease severity, as well as electrophysiological and histopathological parameters of inflammatory demyelination compared to vehicle- and isotype antibody-treated mice. Consistent with in vitro observations of leukocyte trafficking at the BNB, electron micrographs of AIDP patient sural nerves demonstrated intact electron-dense endoneurial microvascular intercellular junctions during paracellular mononuclear leukocyte transmigration. Our data support a crucial pathogenic role of CD11b in AIDP leukocyte trafficking, providing a potential therapeutic target for demyelinating variants of Guillain-Barré syndrome.

  6. Hierarchical macroscopic fibrillar adhesives: in situ study of buckling and adhesion mechanisms on wavy substrates.

    PubMed

    Bauer, Christina T; Kroner, Elmar; Fleck, Norman A; Arzt, Eduard

    2015-10-23

    Nature uses hierarchical fibrillar structures to mediate temporary adhesion to arbitrary substrates. Such structures provide high compliance such that the flat fibril tips can be better positioned with respect to asperities of a wavy rough substrate. We investigated the buckling and adhesion of hierarchically structured adhesives in contact with flat smooth, flat rough and wavy rough substrates. A macroscopic model for the structural adhesive was fabricated by molding polydimethylsiloxane into pillars of diameter in the range of 0.3-4.8 mm, with up to three different hierarchy levels. Both flat-ended and mushroom-shaped hierarchical samples buckled at preloads one quarter that of the single level structures. We explain this behavior by a change in the buckling mode; buckling leads to a loss of contact and diminishes adhesion. Our results indicate that hierarchical structures can have a strong influence on the degree of adhesion on both flat and wavy substrates. Strategies are discussed that achieve highly compliant substrates which adhere to rough substrates.

  7. Terbinafine inhibits gap junctional intercellular communication.

    PubMed

    Lee, Ju Yeun; Yoon, Sei Mee; Choi, Eun Ju; Lee, Jinu

    2016-09-15

    Terbinafine is an antifungal agent that selectively inhibits fungal sterol synthesis by blocking squalene epoxidase. We evaluated the effect of terbinafine on gap junctional intercellular communication (GJIC). Fluorescence recovery after photobleaching (FRAP) and I-YFP GJIC assays revealed that terbinafine inhibits GJIC in a reversible and dose-dependent manner in FRT-Cx43 and LN215 cells. Treatment with terbinafine did not affect Cx43 phosphorylation status or intracellular Ca(2+) concentration, well-known action mechanisms of various GJIC blockers. While a structurally related chemical, naftifine, attenuated GJIC, epigallocatechin gallate, another potent squalene epoxidase inhibitor with a different structure, did not. These results suggest that terbinafine inhibits GJIC with a so far unknown mechanism of action. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. [FUNCTION OF INTERCELLULAR ADHESION A, FIBRINOGEN BINDING PROTEIN, AND ACCUMULATION-ASSOCIATED PROTEIN GENES IN FORMATION OF STAPHYLOCOCCUS EPIDERMIDIS-CANDIDA ALBICANS MIXED SPECIES BIOFILMS].

    PubMed

    Wang, Xiaoyan; Chen, Ying; Huang, Yunchao; Zhou, Youquan; Zhao, Guangqiang; Ye, Lianhua; Lei, Yujie; Tang, Qi

    2015-01-01

    To explore the function of intercellular adhesion A (icaA), fibrinogen binding protein (fbe), and accumulation-associated protein (aap) genes in formation of Staphylococcus epidermidis-Candida albicans mixed species biofilms. The experiment was divided into 3 groups: single culture of Staphylococcus epidermidis ATCC35984 (S. epidermidis group) or Candida albicans ATCC10231 (C. albicans group), and co-culture of two strains (mixed group) to build in vitro biofilm model. Biofilm mass was detected by crystal violet semi-quantitative adherence assay at 2, 4, 6, 8, 12, 24, 48, and 72 hours after incubation. XTT assay was performed to determine the growth kinetics in the same time. Scanning electron microscopy (SEM) was used to observe the ultrastructure of the biofilms after 24 and 72 hours of incubation. The expressions of icaA, fbe, and aap genes were analyzed by real-time fluorescent quantitative PCR. Crystal violet semi-quantitative adherence assay showed that the biofilms thickened at 12 hours in the S. epidermidis and mixed groups; after co-cultured for 72 hours the thickness of biofilm in mixed group was more than that in the S. epidermidis group, and there was significant difference between 2 groups at the other time (P < 0.05) except at 72 hours (P > 0.05). In C. albicans group, the biofilm started to grow at 12 hours of cultivation, but the thickness of the biofilm was significantly lower than that in the mixed group in all the time points (P < 0.05). XTT assay showed that the overall growth speed in the mixed group was greater than that in the C. albicans group, and it was greater than that in the S. epidermidis group at 48 hours; there was no significant difference in the growth speed between the mixed groups and the S. epidermidis group in the other time points (P > 0.05) except at 12 hours (P < 0.05). The absorbance (A) value in the mixed group was lower than that in the S. epidermidis group at 2 and 4 hours, but no significant difference was shown (P > 0.05); the A value of mixed group was significantly higher than that of the C. albicans group after 6 hours (P < 0.05). SEM observation showed that mature biofilms with complex structure formed in all groups. The real-time fluorescent quantitative PCR showed the expressions of fbe, icaA, and aap genes in mixed group increased 1.93, 1.52, and 1.46 times respectively at 72 hours compared with the S. epidermidis group (P < 0.05). Mixed species biofilms have more complex structure and are thicker than single species biofilms of Staphylococcus epidermidis or Candida albicans, which is related to increased expressions of the icaA, fbe, and aap genes of Staphylococcus epidermidis.

  9. Analysis of gap junctional intercellular communications using a dielectrophoresis-based microchip.

    PubMed

    Tellez-Gabriel, Marta; Charrier, Céline; Brounais-Le Royer, Bénédicte; Mullard, Mathilde; Brown, Hannah K; Verrecchia, Franck; Heymann, Dominique

    2017-03-01

    Gap junctions are transmembrane structures that directly connect the cytoplasm of adjacent cells, making intercellular communications possible. It has been shown that the behaviour of several tumours - such as bone tumours - is related to gap junction intercellular communications (GJIC). Several methodologies are available for studying GJIC, based on measuring different parameters that are useful for multiple applications, such as the study of carcinogenesis for example. These methods nevertheless have several limitations. The present manuscript describes the setting up of a dielectrophoresis (DEP)-based lab-on-a-chip platform for the real-time study of Gap Junctional Intercellular Communication between osteosarcoma cells and the main cells accessible to their microenvironment. We conclude that using the DEParray technology for the GJIC assessment has several advantages comparing to current techniques. This methodology is less harmful for cells integrity; cells can be recovered after interaction to make further molecular analysis; it is possible to study GJIC in real time; we can promote cell interactions using up to five different populations. The setting up of this new methodology overcomes several difficulties to perform experiments for solving questions about GJIC process that we are not able to do with current technics. Copyright © 2017 Elsevier GmbH. All rights reserved.

  10. Intercellular signaling pathways active during intervertebral disc growth, differentiation, and aging.

    PubMed

    Dahia, Chitra Lekha; Mahoney, Eric J; Durrani, Atiq A; Wylie, Christopher

    2009-03-01

    Intervertebral discs at different postnatal ages were assessed for active intercellular signaling pathways. To generate a spatial and temporal map of the signaling pathways active in the postnatal intervertebral disc (IVD). The postnatal IVD is a complex structure, consisting of 3 histologically distinct components, the nucleus pulposus, fibrous anulus fibrosus, and endplate. These differentiate and grow during the first 9 weeks of age in the mouse. Identification of the major signaling pathways active during and after the growth and differentiation period will allow functional analysis using mouse genetics and identify targets for therapy for individual components of the disc. Antibodies specific for individual cell signaling pathways were used on cryostat sections of IVD at different postnatal ages to identify which components of the IVD were responding to major classes of intercellular signal, including sonic hedgehog, Wnt, TGFbeta, FGF, and BMPs. We present a spatial/temporal map of these signaling pathways during growth, differentiation, and aging of the disc. During growth and differentiation of the disc, its different components respond at different times to different intercellular signaling ligands. Most of these are dramatically downregulated at the end of disc growth.

  11. Intrinsically disordered proteins aggregate at fungal cell-to-cell channels and regulate intercellular connectivity.

    PubMed

    Lai, Julian; Koh, Chuan Hock; Tjota, Monika; Pieuchot, Laurent; Raman, Vignesh; Chandrababu, Karthik Balakrishna; Yang, Daiwen; Wong, Limsoon; Jedd, Gregory

    2012-09-25

    Like animals and plants, multicellular fungi possess cell-to-cell channels (septal pores) that allow intercellular communication and transport. Here, using a combination of MS of Woronin body-associated proteins and a bioinformatics approach that identifies related proteins based on composition and character, we identify 17 septal pore-associated (SPA) proteins that localize to the septal pore in rings and pore-centered foci. SPA proteins are not homologous at the primary sequence level but share overall physical properties with intrinsically disordered proteins. Some SPA proteins form aggregates at the septal pore, and in vitro assembly assays suggest aggregation through a nonamyloidal mechanism involving mainly α-helical and disordered structures. SPA loss-of-function phenotypes include excessive septation, septal pore degeneration, and uncontrolled Woronin body activation. Together, our data identify the septal pore as a complex subcellular compartment and focal point for the assembly of unstructured proteins controlling diverse aspects of intercellular connectivity.

  12. Surface and buried interfacial structures of epoxy resins used as underfills studied by sum frequency generation vibrational spectroscopy.

    PubMed

    Vázquez, Anne V; Holden, Brad; Kristalyn, Cornelius; Fuller, Mike; Wilkerson, Brett; Chen, Zhan

    2011-05-01

    Flip chip technology has greatly improved the performance of semiconductor devices, but relies heavily on the performance of epoxy underfill adhesives. Because epoxy underfills are cured in situ in flip chip semiconductor devices, understanding their surface and interfacial structures is critical for understanding their adhesion to various substrates. Here, sum frequency generation (SFG) vibrational spectroscopy was used to study surface and buried interfacial structures of two model epoxy resins used as underfills in flip chip devices, bisphenol A digylcidyl ether (BADGE) and 1,4-butanediol diglycidyl ether (BDDGE). The surface structures of these epoxies were compared before and after cure, and the orientations of their surface functional groups were deduced to understand how surface structural changes during cure may affect adhesion properties. Further, the effect of moisture exposure, a known cause of adhesion failure, on surface structures was studied. It was found that the BADGE surface significantly restructured upon moisture exposure while the BDDGE surface did not, showing that BADGE adhesives may be more prone to moisture-induced delamination. Lastly, although surface structure can give some insight into adhesion, buried interfacial structures more directly correspond to adhesion properties of polymers. SFG was used to study buried interfaces between deuterated polystyrene (d-PS) and the epoxies before and after moisture exposure. It was shown that moisture exposure acted to disorder the buried interfaces, most likely due to swelling. These results correlated with lap shear adhesion testing showing a decrease in adhesion strength after moisture exposure. The presented work showed that surface and interfacial structures can be correlated to adhesive strength and may be helpful in understanding and designing optimized epoxy underfill adhesives.

  13. Radiation results in IL-8 mediated intercellular signaling that increases adhesion between monocytic cells and aortic endothelium

    NASA Astrophysics Data System (ADS)

    Kucik, Dennis; Babitz, Stephen; Dunaway, Chad; Steele, Chad

    Epidemiological evidence has established terrestrial radiation exposure as a risk factor for cardiovascular disease. For example, a major side effect of therapeutic radiation, especially for breast and head-and-neck cancers, is atherosclerosis, which can result in stroke years after treatment. Similarly, atomic bomb survivors were significantly more likely to die of cardiovascular disease than their countrymen. Even radiation technologists, prior to 1950 (when regulations governing shielding and occupational exposure were less rigorous) had an increased risk of clinically significant atherosclerosis. We have recently shown that 600 MeV (56) Fe similarly exacerbates plaque formation in the apoE mouse atherosclerosis model at doses 4-7 fold lower than required for x-rays to produce a similar pro-atherogenic effect. This raises concern that exposure to cosmic radiation might pose a similar risk for astronauts. Because so little is known about the mechanism of pro-atherogenic radiation effects, however, the current strategy to minimize risk from terrestrial radiation sources is to limit exposure. For astronauts on deep space missions, exposure to a significant amount of radiation will be unavoidable. Therefore, an understanding of the mechanism of radiation-induced atherosclerosis will be essential in order to develop countermeasures. Radiation can cause increased adhesiveness of vascular endothelium, leading to inappropriate accumulation of monocytes and other white blood cells, which can initiate a self-perpetuating inflammatory response. This vascular inflammation is an early event in atherosclerosis that can eventually lead to clinically significant cardiovascular events such as myocardial infarction and stroke. We showed earlier that x-rays, (56) Fe, and (28) Si all accelerate development of atherosclerosis in the apoE -/- mouse model. We also demonstrated that both x-rays and heavy ions increase adhesion of monocytic cells to vascular human aortic endothelial cells (HAECs) in vitro under conditions that mimic the shear stress in the bloodstream. For both heavy ions and x-rays, these adhesiveness changes are independent of adhesion molecule expression levels, but are chemokine dependent. Here we identify the specific endothelial chemokine responsible for this radiation-induced adhesiveness. X-irradiation increased IL-8 secretion almost 5-fold, while having little or no effect on expression of 15 other chemokines. Adhesiveness was then assayed under physiological shear stress using a flow chamber adhesion assay. Radiation significantly increased endothelial adhesiveness. The radiation-induced adhesiveness was specifically blocked by anti-IL-8 antibody, with no effect on baseline, radiation-independent adhesion. Addition of recombinant human IL-8 to un-irradiated HAECs was sufficient to increase adhesion to the same level as x-rays. Therefore, radiation-induced IL-8 signaling is both necessary and sufficient for radiation effects on aortic endothelial adhesiveness. This IL-8 induced adhesiveness may explain, at least in part, the mechanism by which radiation accelerates development of atherosclerosis. A better understanding of this mechanism can provide the basis for future countermeasure development.

  14. Protective effects of hydrogen-rich medium on lipopolysaccharide-induced monocytic adhesion and vascular endothelial permeability through regulation of vascular endothelial cadherin.

    PubMed

    Yu, Y; Wang, W N; Han, H Z; Xie, K L; Wang, G L; Yu, Y H

    2015-06-11

    We observed the effect of hydrogen-rich medium on lipopolysaccharide (LPS)-induced human umbilical vein endothelial cells (HUVECs), hyaline leukocyte conglutination, and permeability of the endothelium. Endotheliocytes were inoculated on 6-well plates and randomly divided into 4 groups: control, H2, LPS, LPS+H2, H2, and LPS+H2 in saturated hydrogen-rich medium. We applied Wright's stain-ing to observe conglutination of hyaline leukocytes and HUVECs, flow cytometry to determine the content of vascular cell adhesion protein 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1), enzyme-linked immunosorbent assay to measure the E-selectin concentration in the cell liquor, the transendothelial electrical resistance (TEER) to test the permeability of endothelial cells, and Western blot and immunofluorescence to test the expression and distribution of vascular endothelial (VE)-cadherin. Compared with control cells, there was an increase in endothelium-hyaline leukocyte conglutination, a reduction in VCAM-1, ICAM-1, and E-selectin, and the TEER value increased obviously. Compared with LPS, there was an obvious reduction in the conglutination of LPS+H2 cells, a reduction in VCAM-1, ICAM-1, and E-selectin levels, and a reduction in the TEER-resistance value, while the expression of VE-cadherin increased. Fluorescence results showed that, compared with control cells, the VE-cadherin in LPS cells was in-complete at the cell joints. Compared with LPS cells, the VE-cadherin in LPS+H2 cells was even and complete at the cell joints. Liquid rich in hydrogen could reduce LPS-induced production of adhesion molecules and endothelium-hyaline leukocyte conglutination, and influence the expression and distribution of VE-cadherin to regulate the permeability of the endothelium.

  15. Allergen-stimulated T lymphocytes from allergic patients induce vascular cell adhesion molecule-1 (VCAM-1) expression and IL-6 production by endothelial cells.

    PubMed Central

    Delneste, Y; Jeannin, P; Gosset, P; Lassalle, P; Cardot, E; Tillie-Leblond, I; Joseph, M; Pestel, J; Tonnel, A B

    1995-01-01

    Adhesion of inflammatory cells to endothelium is a critical step for their transvascular migration to inflammatory sites. To evaluate the relationship between T lymphocytes (TL) and vascular endothelium, supernatants from allergen-stimulated TL obtained from patients sensitive to Dermatophagoides pteronyssinus (Dpt) versus healthy subjects were added to endothelial cell (EC) cultures. TL were stimulated by autologous-activated antigen-presenting cells (APC) previously fixed in paraformaldehyde to prevent monokine secretion. Two parameters were measured: the expression of adhesion molecule and the production of IL-6. Related allergen-stimulated TL supernatants from allergic patients induced an increase of VCAM-1 and intercellular adhesion molecule-1 (ICAM-1) expression when supernatants of the control groups (TL exposed to an unrelated allergen or not stimulated or TL obtained from healthy subjects) did not. E-selectin expression was not modulated whatever the supernatant added to EC culture. IL-6 production by EC was significantly enhanced after activation with related allergen-stimulated TL supernatants from allergics compared with control supernatants. Induction of VCAM-1 expression was inhibited by adding neutralizing antibodies against IL-4, whereas IL-6 production and ICAM-1 expression were inhibited by anti-interferon-gamma (IFN-gamma) antibodies. Enhanced production of IL-4 and IFN-gamma was detected in related allergen-stimulated TL supernatants from allergic subjects compared with the different supernatants. These data suggest that allergen-specific TL present in the peripheral blood of allergic patients are of Th1 and Th2 subtypes. Their stimulation in allergic patients may lead to the activation of endothelial cells and thereby participate in leucocyte recruitment towards the inflammatory site. PMID:7542574

  16. In vivo imaging of endothelial cell adhesion molecule expression after radiosurgery in an animal model of arteriovenous malformation.

    PubMed

    Raoufi-Rad, Newsha; McRobb, Lucinda S; Lee, Vivienne S; Bervini, David; Grace, Michael; Ukath, Jaysree; Mchattan, Joshua; Sreenivasan, Varun K A; Duong, T T Hong; Zhao, Zhenjun; Stoodley, Marcus A

    2017-01-01

    Focussed radiosurgery may provide a means of inducing molecular changes on the luminal surface of diseased endothelium to allow targeted delivery of novel therapeutic compounds. We investigated the potential of ionizing radiation to induce surface expression of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) on endothelial cells (EC) in vitro and in vivo, to assess their suitability as vascular targets in irradiated arteriovenous malformations (AVMs). Cultured brain microvascular EC were irradiated by linear accelerator at single doses of 0, 5, 15 or 25 Gy and expression of ICAM-1 and VCAM-1 measured by qRT-PCR, Western, ELISA and immunocytochemistry. In vivo, near-infrared (NIR) fluorescence optical imaging using Xenolight 750-conjugated ICAM-1 or VCAM-1 antibodies examined luminal biodistribution over 84 days in a rat AVM model after Gamma Knife surgery at a single 15 Gy dose. ICAM-1 and VCAM-1 were minimally expressed on untreated EC in vitro. Doses of 15 and 25 Gy stimulated expression equally; 5 Gy was not different from the unirradiated. In vivo, normal vessels did not bind or retain the fluorescent probes, however binding was significant in AVM vessels. No additive increases in probe binding were found in response to radiosurgery at a dose of 15 Gy. In summary, radiation induces adhesion molecule expression in vitro but elevated baseline levels in AVM vessels precludes further induction in vivo. These molecules may be suitable targets in irradiated vessels without hemodynamic derangement, but not AVMs. These findings demonstrate the importance of using flow-modulated, pre-clinical animal models for validating candidate proteins for vascular targeting in irradiated AVMs.

  17. Compound Danshen injection improves endotoxin-induced microcirculatory disturbance in rat mesentery

    PubMed Central

    Han, Jing-Yan; Horie, Yoshinori; Miura, Soichiro; Akiba, Yasutada; Guo, Jun; Li, Dan; Fan, Jing-Yu; Liu, Yu-Ying; Hu, Bai-He; An, Li-Hua; Chang, Xin; Xu, Man; Guo, De-An; Sun, Kai; Yang, Ji-Ying; Fang, Shu-Ping; Xian, Ming-Ji; Kizaki, Masahiro; Nagata, Hiroshi; Hibi, Toshifumi

    2007-01-01

    AIM: To investigate the effect of compound Danshen injection on lipopolysaccharide (LPS)-induced rat mesenteric microcirculatory dysfunctions and the underlying possible mechanism by an inverted intravital microscope and high-speed video camera system. METHODS: LPS was continuously infused through the jugular artery of male Wistar rats at the dose of 2 mg/kg per hour. Changes in mesenteric microcirculation, such as diameters of arterioles and venules, velocity of RBCs in venules, leukocyte rolling, adhesion and emigration, free radicals released from post-capillary venules, FITC-albumin leakage and mast cell degranulation, were observed through an inverted intravital microscope assisted with CCD camera and SIT camera. Meanwhile, the expression of adhesion molecules CD11b/CD18 and the production of free radical in neutrophils, and the expression of intercellular adhesion molecule 1 (ICAM-1) in human umbilical vein endothelial cells (HUVECs) were quantified by flow cytometry (FACS) in vitro. RESULTS: The continuous infusion with LPS resulted in a number of responses in microcirculation, including a significant increase in the positive region of venule stained with Monastral blue B, rolling and adhesion of leukocytes, production of oxygen radical in venular wall, albumin efflux and enhanced mast cell degranulation in vivo, all of which, except for the leukocyte rolling, were attenuated by the treatment with compound Danshen injection. Experiments performed in vitro further revealed that the expression of CD11b/CD18 and the production of oxygen free radical in neutrophils, and the expression of ICAM-1 in HUVECs were increased by exposure to LPS, and they were attenuated by compound Danshen injection. CONCLUSION: These results suggest that compound Danshen injection is an efficient drug with multi-targeting potential for improving the microcirculatory disturbance. PMID:17659708

  18. Differential patterns of endothelial and leucocyte activation in ‘typhus-like’ illnesses in Laos and Thailand

    PubMed Central

    Paris, D H; Jenjaroen, K; Blacksell, S D; Phetsouvanh, R; Wuthiekanun, V; Newton, P N; Day, N P J; Turner, G D H

    2008-01-01

    Scrub typhus is responsible for a large proportion of undifferentiated fevers in south-east Asia. The cellular tropism and pathophysiology of the causative agent, Orientia tsutsugamushi, remain poorly understood. We measured endothelial and leucocyte activation by soluble cell adhesion molecule enzyme-linked immunosorbent assays in 242 Lao and Thai patients with scrub or murine typhus, leptospirosis, dengue, typhoid and uncomplicated falciparum malaria on admission to hospital. Soluble E-selectin (sE-selectin) levels were lowest in dengue, sL-selectin highest in scrub typhus with a high sE-selectin to sL-selectin ratio in leptospirosis patients. In scrub typhus patients elevated sL-selectin levels correlated with the duration of skin rash (P = 0·03) and the presence of eschar (P = 0·03), elevated white blood cell (WBC) count (P = 0·007), elevated lymphocyte (P = 0·007) and neutrophil counts (P = 0·015) and elevated levels of sE-selectin correlated with the duration of illness before admission (P = 0·03), the presence of lymphadenopathy (P = 0·033) and eschar (P = 0·03), elevated WBC (P = 0·005) and neutrophil counts (P = 0·0003). In comparison, soluble selectin levels in murine typhus patients correlated only with elevated WBC counts (P = 0·03 for sE-selectin and sL-selectin). Soluble intercellular adhesion molecule-1 and soluble vascular adhesion molecule-1 levels were not associated significantly with any clinical parameters in scrub or murine typhus patients. The data presented suggest mononuclear cell activation in scrub typhus. As adhesion molecules direct leucocyte migration and induce inflammatory and immune responses, this may represent O. tsutsugamushi tropism during early dissemination, or local immune activation within the eschar. PMID:18505434

  19. Differential patterns of endothelial and leucocyte activation in 'typhus-like' illnesses in Laos and Thailand.

    PubMed

    Paris, D H; Jenjaroen, K; Blacksell, S D; Phetsouvanh, R; Wuthiekanun, V; Newton, P N; Day, N P J; Turner, G D H

    2008-07-01

    Scrub typhus is responsible for a large proportion of undifferentiated fevers in south-east Asia. The cellular tropism and pathophysiology of the causative agent, Orientia tsutsugamushi, remain poorly understood. We measured endothelial and leucocyte activation by soluble cell adhesion molecule enzyme-linked immunosorbent assays in 242 Lao and Thai patients with scrub or murine typhus, leptospirosis, dengue, typhoid and uncomplicated falciparum malaria on admission to hospital. Soluble E-selectin (sE-selectin) levels were lowest in dengue, sL-selectin highest in scrub typhus with a high sE-selectin to sL-selectin ratio in leptospirosis patients. In scrub typhus patients elevated sL-selectin levels correlated with the duration of skin rash (P = 0.03) and the presence of eschar (P = 0.03), elevated white blood cell (WBC) count (P = 0.007), elevated lymphocyte (P = 0.007) and neutrophil counts (P = 0.015) and elevated levels of sE-selectin correlated with the duration of illness before admission (P = 0.03), the presence of lymphadenopathy (P = 0.033) and eschar (P = 0.03), elevated WBC (P = 0.005) and neutrophil counts (P = 0.0003). In comparison, soluble selectin levels in murine typhus patients correlated only with elevated WBC counts (P = 0.03 for sE-selectin and sL-selectin). Soluble intercellular adhesion molecule-1 and soluble vascular adhesion molecule-1 levels were not associated significantly with any clinical parameters in scrub or murine typhus patients. The data presented suggest mononuclear cell activation in scrub typhus. As adhesion molecules direct leucocyte migration and induce inflammatory and immune responses, this may represent O. tsutsugamushi tropism during early dissemination, or local immune activation within the eschar.

  20. Compound Danshen injection improves endotoxin-induced microcirculatory disturbance in rat mesentery.

    PubMed

    Han, Jing-Yan; Horie, Yoshinori; Miura, Soichiro; Akiba, Yasutada; Guo, Jun; Li, Dan; Fan, Jing-Yu; Liu, Yu-Ying; Hu, Bai-He; An, Li-Hua; Chang, Xin; Xu, Man; Guo, De-An; Sun, Kai; Yang, Ji-Ying; Fang, Shu-Ping; Xian, Ming-Ji; Kizaki, Masahiro; Nagata, Hiroshi; Hibi, Toshifumi

    2007-07-14

    To investigate the effect of compound Danshen injection on lipopolysaccharide (LPS)-induced rat mesenteric microcirculatory dysfunctions and the underlying possible mechanism by an inverted intravital microscope and high-speed video camera system. LPS was continuously infused through the jugular artery of male Wistar rats at the dose of 2 mg/kg per hour. Changes in mesenteric microcirculation, such as diameters of arterioles and venules, velocity of RBCs in venules, leukocyte rolling, adhesion and emigration, free radicals released from post-capillary venules, FITC-albumin leakage and mast cell degranulation, were observed through an inverted intravital microscope assisted with CCD camera and SIT camera. Meanwhile, the expression of adhesion molecules CD11b/CD18 and the production of free radical in neutrophils, and the expression of intercellular adhesion molecule 1 (ICAM-1) in human umbilical vein endothelial cells (HUVECs) were quantified by flow cytometry (FACS) in vitro. The continuous infusion with LPS resulted in a number of responses in microcirculation, including a significant increase in the positive region of venule stained with Monastral blue B, rolling and adhesion of leukocytes, production of oxygen radical in venular wall, albumin efflux and enhanced mast cell degranulation in vivo, all of which, except for the leukocyte rolling, were attenuated by the treatment with compound Danshen injection. Experiments performed in vitro further revealed that the expression of CD11b/CD18 and the production of oxygen free radical in neutrophils, and the expression of ICAM-1 in HUVECs were increased by exposure to LPS, and they were attenuated by compound Danshen injection. These results suggest that compound Danshen injection is an efficient drug with multi-targeting potential for improving the microcirculatory disturbance.

  1. Quantitative genetic analysis of cellular adhesion molecules: the Fels Longitudinal Study.

    PubMed

    Lee, Miryoung; Czerwinski, Stefan A; Choh, Audrey C; Demerath, Ellen W; Sun, Shumei S; Chumlea, Wm C; Towne, Bradford; Siervogel, Roger M

    2006-03-01

    Circulating concentrations of inflammatory markers predict cardiovascular disease (CVD) risk and are closely associated with obesity. However, little is known concerning genetic influences on serum levels of inflammatory markers. In this study, we estimated the heritability (h2) of soluble cellular adhesion molecule (sCAM) concentrations and examined the correlational architecture between different sCAMs. The study population included 234 men and 270 women aged 18-76 years, belonging to 121 families participating in the Fels Longitudinal Study. Serum levels of soluble intercellular adhesion molecule-1 (sICAM-1), vascular cell adhesion molecule-1 (sVCAM-1), E-selectin (sESEL-1) and P-selectin (sPSEL-1) were assayed using commercially available kits. A variance components-based maximum likelihood method was used to estimate the h2 of the different serum inflammatory markers while simultaneously adjusting for the effects of known CVD risk factors, such as age and smoking. Additionally, we used bivariate extensions of these methods to estimate genetic and random environmental correlations among sCAMs. Levels of sCAMs were significantly heritable: h2=0.24+/-0.10 for sICAM-1, h2=0.22+/-0.10 for sVCAM-1, h2=0.50+/-0.11 for sESEL-1, and h2=0.46+/-0.10 for sPSEL-1. In addition, a significant genetic correlation (rho(G)=0.63) was found between sICAM-1 and sVCAM-1 indicating some degree of shared genetic control. In the Fels Longitudinal Study, the levels of four sCAMs are significantly influenced by genetic effects, and sICAM-1 shares a common genetic background with sVCAM-1.

  2. Adhesion molecules, chemokines and matrix metallo-proteinases response after albendazole and albendazole plus steroid therapy in swine neurocysticercosis.

    PubMed

    Singh, Satyendra K; Prasad, Kashi N; Singh, Aloukick K; Gupta, Kamlesh K; Singh, Amrita; Tripathi, Mukesh; Gupta, Rakesh K

    2017-11-01

    The treatment of neurocysticercosis (NCC) varies with location, number and stage of the Taenia solium cysticerci (cysts). Albendazole (ABZ) effectively kills cysticerci, and subsequently induces neuro-inflammation facilitated by leukocyte infiltration. We hypothesize that immune response varies around drug responder (degenerating/dying) and non-responder (viable) cysts after ABZ and ABZ plus steroid (ABZS) therapy, which may determine the disease pathogenesis. Twenty cysticercotic swine were treated with ABZ (n = 10; group1) and ABZS (n = 10; group2). Expression of adhesion molecules, chemokines and matrix metallo-proteinases (MMPs) was measured by qRT-PCR (quantitative reverse transcriptase-polymerase chain reaction) and ELISA. Gelatin gel zymography was performed to detect the activity of MMP-2 and -9. In group1, ABZ therapy induced higher expressions of ICAM-1 (intercellular adhesion molecule-1), VCAM-1 (vascular cell adhesion molecule-1), E-selectin, MCP-1 (monocyte chemotactic protein-1), Eotaxin-1, MIP-1α (macrophage inflammatory protein-1α), RANTES (regulated on activation, normal T cell expressed and secreted), MMP-2 and MMP-9 around ABZ responder (AR) cysts. Three pigs with cyst burdens ≥10 died following ABZ therapy. However, in group2, moderate expressions of ICAM-1, VCAM-1, E-selectin, RANTES and MMP-9 were associated with ABZS responder (ASR), whereas low expressions of these molecules were associated with ABZS non-responder (ASNR) cysts. In conclusion, ABZ alone therapy is not safe since it causes death of pigs due to higher inflammatory immune response around dying cysts. However, combination therapy is an effective treatment regimen even with the high cyst burden. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Calcium Dobesilate Inhibits the Alterations in Tight Junction Proteins and Leukocyte Adhesion to Retinal Endothelial Cells Induced by Diabetes

    PubMed Central

    Leal, Ermelindo C.; Martins, João; Voabil, Paula; Liberal, Joana; Chiavaroli, Carlo; Bauer, Jacques; Cunha-Vaz, José; Ambrósio, António F.

    2010-01-01

    OBJECTIVE Calcium dobesilate (CaD) has been used in the treatment of diabetic retinopathy in the last decades, but its mechanisms of action are not elucidated. CaD is able to correct the excessive vascular permeability in the retina of diabetic patients and in experimental diabetes. We investigated the molecular and cellular mechanisms underlying the protective effects of CaD against the increase in blood–retinal barrier (BRB) permeability induced by diabetes. RESEARCH DESIGN AND METHODS Wistar rats were divided into three groups: controls, streptozotocin-induced diabetic rats, and diabetic rats treated with CaD. The BRB breakdown was evaluated using Evans blue. The content or distribution of tight junction proteins (occludin, claudin-5, and zonula occluden-1 [ZO-1]), intercellular adhesion molecule-1 (ICAM-1), and p38 mitogen-activated protein kinase (p38 MAPK) was evaluated by Western blotting and immunohistochemistry. Leukocyte adhesion was evaluated in retinal vessels and in vitro. Oxidative stress was evaluated by the detection of oxidized carbonyls and tyrosine nitration. NF-κB activation was measured by enzyme-linked immunosorbent assay. RESULTS Diabetes increased the BRB permeability and retinal thickness. Diabetes also decreased occludin and claudin-5 levels and altered the distribution of ZO-1 and occludin in retinal vessels. These changes were inhibited by CaD treatment. CaD also inhibited the increase in leukocyte adhesion to retinal vessels or endothelial cells and in ICAM-1 levels, induced by diabetes or elevated glucose. Moreover, CaD decreased oxidative stress and p38 MAPK and NF-κB activation caused by diabetes. CONCLUSIONS CaD prevents the BRB breakdown induced by diabetes, by restoring tight junction protein levels and organization and decreasing leukocyte adhesion to retinal vessels. The protective effects of CaD are likely to involve the inhibition of p38 MAPK and NF-κB activation, possibly through the inhibition of oxidative/nitrosative stress. PMID:20627932

  4. Altered Monocyte and Endothelial Cell Adhesion Molecule Expression Is Linked to Vascular Inflammation in Human Immunodeficiency Virus Infection.

    PubMed

    Kulkarni, Manjusha; Bowman, Emily; Gabriel, Janelle; Amburgy, Taylor; Mayne, Elizabeth; Zidar, David A; Maierhofer, Courtney; Turner, Abigail Norris; Bazan, Jose A; Koletar, Susan L; Lederman, Michael M; Sieg, Scott F; Funderburg, Nicholas T

    2016-10-01

    Human immunodeficiency virus (HIV)-infected individuals have increased risk for vascular thrombosis, potentially driven by interactions between activated leukocytes and the endothelium. Monocyte subsets (CD14 + CD16 - , CD14 + CD16 + , CD14 Dim CD16 + ) from HIV negative (HIV - ) and antiretroviral therapy-treated HIV positive (HIV + ) participants (N = 19 and 49) were analyzed by flow cytometry for adhesion molecule expression (lymphocyte function-associated antigen 1 [LFA-1], macrophage-1 antigen [Mac-1], CD11c/CD18, very late antigen [VLA]-4) and the fractalkine receptor (CX3CR1); these receptors recognize ligands (intercellular adhesion molecules [ICAMs], vascular cell adhesion molecule [VCAM]-1, fractalkine) on activated endothelial cells (ECs) and promote vascular migration. Plasma markers of monocyte (soluble [s]CD14, sCD163) and EC (VCAM-1, ICAM-1,2, fractalkine) activation and systemic (tumor necrosis factor receptor [TNFR-I], TNFR-II) and vascular (lipoprotein-associated phospholipase A 2 [Lp-PLA 2 ]) inflammation were measured by enzyme-linked immunosorbent assay. Proportions of CD16 + monocyte subsets were increased in HIV + participants. Among all monocyte subsets, levels of LFA-1 were increased and CX3CR1 levels were decreased in HIV + participants ( P < .01). Levels of sCD163, sCD14, fractalkine, ICAM-1, VCAM-1, TNFR-II, and Lp-PLA 2 were also increased in HIV + participants ( P < .05), and levels of sCD14, TNFR-I, and TNFR-II were directly related to ICAM-1 and VCAM-1 levels in HIV + participants. Expression of CX3CR1 on monocyte subsets was inversely related to plasma Lp-PLA 2 ( P < .05 for all). Increased proportions of CD16 + monocytes, cells with altered adhesion molecule expression, combined with elevated levels of their ligands, may promote vascular inflammation in HIV infection. © The Author 2016. Published by Oxford University Press on behalf of the Infectious Diseases Society of America.

  5. Effects of angiopoietin-1 on inflammatory injury in endothelial progenitor cells and blood vessels.

    PubMed

    Wang, Yi-Qing; Song, Jing-Jin; Han, Xiao; Liu, Yi-Ye; Wang, Xi-Huang; Li, Zhi-Ming; Tzeng, Chi-Meng

    2014-01-01

    Endothelial progenitor cells (EPCs) and angiopoietin-1 (Ang-1) play important roles in vasculogenesis and angiogenesis, respectively. Thus, targeting both aspects of cardiovascular tissue regeneration may offer promising therapeutic options for cardiovascular disorders. To this end, we constructed a lentiviral vector (pNL) with the Ang-1 gene and transfected EPCs with it (Ang-1-EPCs) to investigate vasculogenesis in both cellular and animal models. Compared to controls, intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) increased significantly in both untreated EPCs and in the pNL vector group. After Ang-1 transcription, ICAM-1 and VCAM-1 decreased considerably in those treatment groups. Ang-1-modified EPCs alleviated inflammatory responses induced by tumor-necrosis factor-α (TNF-α) in vitro. Moreover, Ang-1-EPC implantation inhibited neointimal hyperplasia after balloon catheter injury in rats, dramatically diminishing the intimal-media (I/M) ratio and decreasing the neointimal area. Proliferating cell nuclear antigen expression in the Ang-1-EPC group was lower than the EPC non-treatment group as well, suggesting that Ang-1-EPC improved cell survival during inflammation and promoted endothelialization in damaged blood vessels.

  6. Polymorphisms and linkage analysis for ICAM-1 and the selectin gene cluster

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vora, D.K.; Rosenbloom, C.L.; Cottingham, R.W.

    1994-06-01

    Genetic polymorphisms in leukocyte and endothelial cell adhesion molecules may be important variables with regard to susceptibility to multifactorial disease processes that include an inflammatory component. For this reason, polymorphisms were sought for intercellular adhesion molecule-1 (ICAM-1; gene symbol ICAM1) and for the three genes in the selectin cluster, P-selectin, L-selectin, and E-selectin (gene symbols SELP, SELL, and SELE, respectively). Two amino acid polymorphisms were identified for ICAM-1; Gly or Arg at codon 241 and Lys or Glu at codon 469. Dinucleotide repeat polymorphisms were identified in the 3{prime}-untranslated region for ICAM-1 and in intron 9 for P-selectin. Restriction fragmentmore » length polymorphisms were found using cDNAs for each of the three selectin genes as probes; E-selectin with BglII, P-selectin with ScaI, and L-selectin with HincII. Linkage analysis was performed for the selectin gene cluster and for ICAM-1 using the CEPH families; ICAM-1 is very tightly linked to the LDL receptor on chromosome 19, and the selectin cluster is linked to markers at chromosome 1q23. 41 refs., 2 tabs.« less

  7. Immunohistochemical localization of cell adhesion molecule epithelial cadherin in human arachnoid villi and meningiomas.

    PubMed

    Tohma, Y; Yamashima, T; Yamashita, J

    1992-04-01

    Cadherins are a family of intercellular glycoproteins responsible for calcium-dependent cell adhesion and are currently divided into four types: epithelial (E), neuronal (N), placental (P), and vascular (V). Since cadherins are known to be indispensable for not only morphogenesis in the embryo but also maintenance of tumor cell nest, we examined the expression of E-cadherin in 31 meningiomas (11 syncytial, 12 transitional, 8 fibroblastic) and 3 arachnoid villi by immunoblot and immunohistochemical analyses. In the immunoblot analysis, E-cadherin was detected at the main band of Mr 124,000 in all of the arachnoid villi, as well as syncytial and transitional types of meningiomas, but not in the fibroblastic type. The immunohistochemical examination showed that E-cadherin was expressed at the cell borders of syncytial and transitional types, but the expression was absent in the fibroblastic type. Immunoelectron microscopy showed that E-cadherin was localized at the intermediate junctions in arachnoid villi, while it was detected diffusely at the cell surface in meningiomas. It is suggested from these data that the expression of E-cadherin might be closely related to the differentiation and organogenesis of meningioma cells.

  8. Prostaglandin E2 suppresses beta1-integrin expression via E-prostanoid receptor in human monocytes/macrophages.

    PubMed

    Hasegawa, Shunji; Ichiyama, Takashi; Kohno, Fumitaka; Korenaga, Yuno; Ohsaki, Ayami; Hirano, Reiji; Haneda, Yasuhiro; Fukano, Reiji; Furukawa, Susumu

    2010-01-01

    Beta1-integrins mediate cell attachment to different extracellular matrix proteins, intracellular proteins, and intercellular adhesions. Recently, it has been reported that prostaglandin E2 (PGE2) has anti-inflammatory properties such as inhibition of the expression of adhesion molecules or production of chemokines. However, the effect of PGE2 on the expression of beta1-integrin remains unknown. In this study, we investigated the effects of PGE2 on the expression of beta1-integrin in the human monocytic cell line THP-1 and in CD14+ monocytes/macrophages in human peripheral blood. For this, we examined the role of four subtypes of PGE2 receptors and E-prostanoid (EP) receptors on PGE2-mediated inhibition. We found that PGE2 significantly inhibited the expression of beta1-integrin, mainly through EP4 receptors in THP-1 cells and CD14+ monocytes/macrophages in human peripheral blood. We suggest that PGE2 has anti-inflammatory effects, leading to the inhibited expression of beta1-integrin in human monocytes/macrophages, and that the EP4 receptor may play an important role in PGE2-mediated inhibition. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  9. Role of tumour necrosis factor receptor-1 and nuclear factor-κB in production of TNF-α-induced pro-inflammatory microparticles in endothelial cells.

    PubMed

    Lee, S K; Yang, S-H; Kwon, I; Lee, O-H; Heo, J H

    2014-09-02

    Tumour necrosis factor-α (TNF-α) is upregulated in many inflammatory diseases and is also a potent agent for microparticle (MP) generation. Here, we describe an essential role of TNF-α in the production of endothelial cell-derived microparticles (EMPs) in vivo and the function of TNF-α-induced EMPs in endothelial cells. We found that TNF-α rapidly increased blood levels of EMPs in mice. Treatment of human umbilical vein endothelial cells (HUVECs) with TNF-α also induced EMP formation in a time-dependent manner. Silencing of TNF receptor (TNFR)-1 or inhibition of the nuclear factor-κB (NF-κB) in HUVECs impaired the production of TNF-α-induced EMP. Incubation of HUVECs with PKH-67-stained EMPs showed that endothelial cells readily engulfed EMPs, and the engulfed TNF-α-induced EMPs promoted the expression of pro-apoptotic molecules and upregulated intercellular adhesion molecule-1 level on the cell surface, which led to monocyte adhesion. Collectively, our findings indicate that the generation of TNF-α-induced EMPs was mediated by TNFR1 or NF-κB and that EMPs can contribute to apoptosis and inflammation of endothelial cells.

  10. Bone morphogenic protein 4 produced in endothelial cells by oscillatory shear stress stimulates an inflammatory response

    NASA Technical Reports Server (NTRS)

    Sorescu, George P.; Sykes, Michelle; Weiss, Daiana; Platt, Manu O.; Saha, Aniket; Hwang, Jinah; Boyd, Nolan; Boo, Yong C.; Vega, J. David; Taylor, W. Robert; hide

    2003-01-01

    Atherosclerosis is now viewed as an inflammatory disease occurring preferentially in arterial regions exposed to disturbed flow conditions, including oscillatory shear stress (OS), in branched arteries. In contrast, the arterial regions exposed to laminar shear (LS) are relatively lesion-free. The mechanisms underlying the opposite effects of OS and LS on the inflammatory and atherogenic processes are not clearly understood. Here, through DNA microarrays, protein expression, and functional studies, we identify bone morphogenic protein 4 (BMP4) as a mechanosensitive and pro-inflammatory gene product. Exposing endothelial cells to OS increased BMP4 protein expression, whereas LS decreased it. In addition, we found BMP4 expression only in the selective patches of endothelial cells overlying foam cell lesions in human coronary arteries. The same endothelial patches also expressed higher levels of intercellular cell adhesion molecule-1 (ICAM-1) protein compared with those of non-diseased areas. Functionally, we show that OS and BMP4 induced ICAM-1 expression and monocyte adhesion by a NFkappaB-dependent mechanism. We suggest that BMP4 is a mechanosensitive, inflammatory factor playing a critical role in early steps of atherogenesis in the lesion-prone areas.

  11. Impacts of ICAM-1 gene polymorphisms on urothelial cell carcinoma susceptibility and clinicopathologic characteristics in Taiwan.

    PubMed

    Wang, Shian-Shiang; Hsieh, Ming-Ju; Ou, Yen-Chuan; Chen, Chuan-Shu; Li, Jian-Ri; Hsiao, Pei-Ching; Yang, Shun-Fa

    2014-08-01

    Intercellular adhesion molecule (ICAM)-1, a cell adhesion molecule, is reportedly overexpressed in several cancers and may contribute to tumorgenesis and metastasis. The current study explored the effect of ICAM-1 gene polymorphisms on the susceptibility of developing urothelial cell carcinoma (UCC) and the clinicopathological status. A total of 558 participants, including 279 healthy people and 279 patients with UCC, were recruited for this study. Four single-nucleotide polymorphisms of the ICAM-1 gene were assessed by a real-time polymerase chain reaction with the TaqMan assay. After adjusting for other covariants, the individuals carrying at least one G allele at ICAM-1 rs5498 had a 1.603-fold risk of developing UCC than did wild-type (AA) carriers. Furthermore, UCC patients who carried at least one G allele at rs5498 had a higher invasive stage risk (p < 0.05) than did patients carrying the wild-type allele. In conclusion, the rs5498 polymorphic genotypes of ICAM-1 might contribute to the prediction of susceptibility to and pathological development of UCC. This is the first study to provide insight into risk factors associated with ICAM-1 variants in carcinogenesis of UCC in Taiwan.

  12. Weight loss improves biomarkers endothelial function and systemic inflammation in obese postmenopausal Saudi women.

    PubMed

    Abd El-Kader, Shehab Mahmoud; Saiem Al-Dahr, Mohammed H

    2016-06-01

    Although postmenopausal associated disorders are important public health problems worldwide, to date limited studies evaluated the endothelial function and systemic inflammation response to weight loss in obese postmenopausal women. This study was done to evaluate the endothelial function and systemic inflammation response to weight loss in obese postmenopausal Saudi women. Eighty postmenopausal obese Saudi women (mean age 52.64±6.13 year) participated in two groups: Group (A) received aerobic exercise on treadmill and diet whereas, group (B) received no intervention. Markers of inflammation and endothelial function were measured before and after 3 months at the end of the study. The values of body mass index(BMI), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), inter-cellular adhesion molecule (ICAM-1), vascular cell adhesion molecule (VCAM-1) and plasminogen activator inhibitor-1 activity (PAI-1:Ac) were significantly decreased in group (A), while changes were not significant in group (B). Also, there were significant differences between mean levels of the investigated parameters in group (A) and group (B) after treatment. Weight loss ameliorates inflammatory cytokines and markers of endothelial function in obese postmenopausal Saudi women.

  13. Phloretin ameliorates chemokines and ICAM-1 expression via blocking of the NF-κB pathway in the TNF-α-induced HaCaT human keratinocytes.

    PubMed

    Huang, Wen-Chung; Dai, Yi-Wen; Peng, Hui-Ling; Kang, Chiao-Wei; Kuo, Chun-Yu; Liou, Chian-Jiun

    2015-07-01

    Previous studies found that phloretin had anti-oxidant, anti-inflammatory, and anti-tumor properties. In this study, we investigated whether phloretin could suppress the production of the intercellular adhesion molecule (ICAM)-1 and chemokines through downregulation of the nuclear transcription factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways in TNF-α-stimulated HaCaT human keratinocytes. HaCaT cells were treated with phloretin and then the cells were stimulated by TNF-α. Phloretin treatment decreased the production of IL-6, IL-8, CCL5, MDC, and TARC. Phloretin decreased ICAM-1 protein and mRNA expression, and also suppressed the adhesion of monocyte THP-1 cells to inflammatory HaCaT cells. Phloretin inhibited NF-κB translocation into the nucleus and also suppressed the phosphorylation of Akt and MAPK signal. In addition, phloretin increased heme oxygenase-1 production in a concentration-dependent manner. These results demonstrated that phloretin has anti-inflammatory effects to inhibit chemokines and ICAM-1 expressions through suppression of the NF-κB and MAPK pathways in human keratinocytes. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Endothelial Msx1 transduces hemodynamic changes into an arteriogenic remodeling response

    PubMed Central

    Vandersmissen, Ine; Craps, Sander; Depypere, Maarten; Coppiello, Giulia; van Gastel, Nick; Maes, Frederik; Carmeliet, Geert; Schrooten, Jan; Jones, Elizabeth A.V.; Umans, Lieve; Devlieger, Roland; Koole, Michel; Gheysens, Olivier; Zwijsen, An; Aranguren, Xabier L.

    2015-01-01

    Collateral remodeling is critical for blood flow restoration in peripheral arterial disease and is triggered by increasing fluid shear stress in preexisting collateral arteries. So far, no arterial-specific mediators of this mechanotransduction response have been identified. We show that muscle segment homeobox 1 (MSX1) acts exclusively in collateral arterial endothelium to transduce the extrinsic shear stimulus into an arteriogenic remodeling response. MSX1 was specifically up-regulated in remodeling collateral arteries. MSX1 induction in collateral endothelial cells (ECs) was shear stress driven and downstream of canonical bone morphogenetic protein–SMAD signaling. Flow recovery and collateral remodeling were significantly blunted in EC-specific Msx1/2 knockout mice. Mechanistically, MSX1 linked the arterial shear stimulus to arteriogenic remodeling by activating the endothelial but not medial layer to a proinflammatory state because EC but not smooth muscle cellMsx1/2 knockout mice had reduced leukocyte recruitment to remodeling collateral arteries. This reduced leukocyte infiltration in EC Msx1/2 knockout mice originated from decreased levels of intercellular adhesion molecule 1 (ICAM1)/vascular cell adhesion molecule 1 (VCAM1), whose expression was also in vitro driven by promoter binding of MSX1. PMID:26391659

  15. MK2 inhibitor reduces alkali burn-induced inflammation in rat cornea

    PubMed Central

    Chen, Yanfeng; Yang, Wenzhao; Zhang, Xiaobo; Yang, Shu; Peng, Gao; Wu, Ting; Zhou, Yueping; Huang, Caihong; Reinach, Peter S.; Li, Wei; Liu, Zuguo

    2016-01-01

    MK2 activation by p38 MAPK selectively induces inflammation in various diseases. We determined if a MK2 inhibitor (MK2i), improves cornea wound healing by inhibiting inflammation caused by burning rat corneas with alkali. Our study, for the first time, demonstrated that MK2i inhibited alkali burn-induced MK2 activation as well as rises in inflammation based on: a) blunting rises in inflammatory index, inflammatory cell infiltration, ED1+ macrophage and PMN+ neutrophil infiltration; b) suppressing IL-6 and IL-1β gene expression along with those of macrophage inflammatory protein-1α (MIP-1α), intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1); c) reducing angiogenic gene expression levels and neovascularization (NV) whereas anti-angiogenic PEDF levels increased. In addition, this study found that MK2i did not affect human corneal epithelial cell (HCEC) proliferation and migration and had no detectable side effects on ocular surface integrity. Taken together, MK2i selectively inhibited alkali burn-induced corneal inflammation by blocking MK2 activation, these effects have clinical relevance in the treatment of inflammation related ocular surface diseases. PMID:27329698

  16. Contact inhibition of locomotion determines cell-cell and cell-substrate forces in tissues.

    PubMed

    Zimmermann, Juliane; Camley, Brian A; Rappel, Wouter-Jan; Levine, Herbert

    2016-03-08

    Cells organized in tissues exert forces on their neighbors and their environment. Those cellular forces determine tissue homeostasis as well as reorganization during embryonic development and wound healing. To understand how cellular forces are generated and how they can influence the tissue state, we develop a particle-based simulation model for adhesive cell clusters and monolayers. Cells are contractile, exert forces on their substrate and on each other, and interact through contact inhibition of locomotion (CIL), meaning that cell-cell contacts suppress force transduction to the substrate and propulsion forces align away from neighbors. Our model captures the traction force patterns of small clusters of nonmotile cells and larger sheets of motile Madin-Darby canine kidney (MDCK) cells. In agreement with observations in a spreading MDCK colony, the cell density in the center increases as cells divide and the tissue grows. A feedback between cell density, CIL, and cell-cell adhesion gives rise to a linear relationship between cell density and intercellular tensile stress and forces the tissue into a nonmotile state characterized by a broad distribution of traction forces. Our model also captures the experimentally observed tissue flow around circular obstacles, and CIL accounts for traction forces at the edge.

  17. Curcumin Protects against Atherosclerosis in Apolipoprotein E-Knockout Mice by Inhibiting Toll-like Receptor 4 Expression.

    PubMed

    Zhang, Shanshan; Zou, Jun; Li, Peiyang; Zheng, Xiumei; Feng, Dan

    2018-01-17

    Toll-like receptor 4 (TLR4) has been reported to play a critical role in the pathogenesis of atherosclerosis, the current study aimed to investigate whether curcumin suppresses atherosclerosis development in ApoE-knockout (ApoE -/- ) mice by inhibiting TLR4 expression. ApoE -/- mice were fed a high-fat diet supplemented with or without curcumin (0.1% w/w) for 16 weeks. Curcumin supplementation significantly reduced TLR4 expression and macrophage infiltration in atherosclerotic plaques. Curcumin also reduced aortic interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) expression, nuclear factor-κB (NF-κB) activity, and plasma IL-1β, TNF-α, soluble VCAM-1 and ICAM-1 levels. In addition, aortic sinus sections revealed that curcumin treatment reduced the extent of atherosclerotic lesions and inhibited atherosclerosis development. In vitro, curcumin inhibited NF-κB activation in macrophages and reduced TLR4 expression induced by lipopolysaccharide. Our results indicate that curcumin protects against atherosclerosis at least partially by inhibiting TLR4 expression and its related inflammatory reaction.

  18. Fate of Neutrophils during the Recovery Phase of Ischemia/Reperfusion Induced Acute Kidney Injury

    PubMed Central

    2017-01-01

    Effective clearance of inflammatory cells is required for resolution of inflammation. Here, we show in vivo evidence that apoptosis and reverse transendothelial migration (rTEM) are important mechanisms in eliminating neutrophils and facilitating recovery following ischemia/reperfusion injury (IRI) of the kidney. The clearance of neutrophils was delayed in the Bax knockout (KO)BM → wild-type (WT) chimera in which bone marrow derived cells are partially resistant to apoptosis, compared to WTBM → WT mice. These mice also showed delayed functional, histological recovery, increased tissue cytokines, and accelerated fibrosis. The circulating intercellular adhesion molecule-1 (ICAM-1)+ Gr-1+ neutrophils displaying rTEM phenotype increased during the recovery phase and blockade of junctional adhesion molecule-C (JAM-C), a negative regulator of rTEM, resulted in an increase in circulating ICAM-1+ neutrophils, faster resolution of inflammation and recovery. The presence of Tamm-Horsfall protein (THP) in circulating ICAM-1+ neutrophils could suggest that they are derived from injured kidneys. In conclusion, we suggest that apoptosis and rTEM are critically involved in the clearance mechanisms of neutrophils during the recovery phase of IRI. PMID:28875605

  19. Increased levels of markers of vascular inflammation in patients with coronary heart disease.

    PubMed

    Schumacher, A; Seljeflot, I; Sommervoll, L; Christensen, B; Otterstad, J E; Arnesen, H

    2002-01-01

    Elevated levels of soluble cell adhesion molecules (sCAMs), inflammatory cytokines and C-reactive protein (CRP) have been associated with atherosclerotic disease states. The aim of the present study was to evaluate whether circulating levels of vascular cell adhesion molecule-1 (sVCAM-1), intercellular adhesion molecule-1 (sICAM-1), E- and P-selectin were significantly elevated in patients with coronary heart disease (CHD) compared with healthy controls, and to study possible associations between these sCAMs, tumour necrosis factor alpha (TNFalpha). interleukin-6 (IL-6), CRP and major CHD risk factors. The study included 193 patients in various stages of CHD and 193 matched controls. To evaluate any possible influence of acute phase reaction, reinvestigation was performed after 6 months. After adjustment for major CHD risk factors, sVCAM-1, sICAM-1, P-selectin, IL-6 and CRP remained significantly elevated in the CHD patients (p for all <0.001). In multivariate analysis sVCAM-1 was predicted by age (p=0.015), sICAM-1 by smoking (p<0.001) and total cholesterol (p=0.026), E-selectin by body mass index (BMI) (p=0.004) and P-selectin by male gender (p=0.015). TNFalpha significantly predicted sICAM-1 and E-selectin levels, while IL-6 predicted CRP but none of the sCAMs measured. This might indicate that TNFalpha, but not IL-6, plays a major role in the regulation of sCAM levels in vivo.

  20. The Anti-Inflammatory Effect of Spray-Dried Plasma Is Mediated by a Reduction in Mucosal Lymphocyte Activation and Infiltration in a Mouse Model of Intestinal Inflammation.

    PubMed

    Pérez-Bosque, Anna; Miró, Lluïsa; Amat, Concepció; Polo, Javier; Moretó, Miquel

    2016-10-22

    Spray-dried preparations from porcine and bovine plasma can alleviate mucosal inflammation in experimental models and improve symptoms in patients with enteropathy. In rodents, dietary supplementation with porcine spray-dried plasma (SDP) attenuates intestinal inflammation and improves the epithelial barrier function during intestinal inflammation induced by Staphylococcus aureus enterotoxin B (SEB). The aim of this study was to discern the molecular mechanisms involved in the anti-inflammatory effects of SDP. Male C57BL/6 mice were fed with 8% SDP or control diet (based on milk proteins) for two weeks, from weaning until day 33. On day 32, the mice were given a SEB dose (i.p., 25 µg/mouse) or vehicle. SEB administration increased cell recruitment to mesenteric lymph nodes and the percentage of activated Th lymphocytes and SDP prevented these effects). SDP supplementation increased the expression of interleukin 10 (IL-10) or transforming growth factor- β (TGF-β) compared to the SEB group. The SEB challenge increased six-fold the expression of mucosal addressin cell adhesion molecule 1 (MAdCAM-1) and intercellular adhesion molecule 1 (ICAM-1); and these effects were attenuated by SDP supplementation. SEB also augmented NF-κB phosphorylation, an effect that was prevented by dietary SDP. Our results indicate that the anti-inflammatory effects of SDP involve the regulation of transcription factors and adhesion molecules that reduce intestinal cell infiltration and the degree of the inflammatory response.

  1. Infection of human intestinal epithelial cells with invasive bacteria upregulates apical intercellular adhesion molecule-1 (ICAM)-1) expression and neutrophil adhesion.

    PubMed Central

    Huang, G T; Eckmann, L; Savidge, T C; Kagnoff, M F

    1996-01-01

    The acute host response to gastrointestinal infection with invasive bacteria is characterized by an accumulation of neutrophils in the lamina propria, and neutrophil transmigration to the luminal side of the crypts. Intestinal epithelial cells play an important role in the recruitment of inflammatory cells to the site of infection through the secretion of chemokines. However, little is known regarding the expression, by epithelial cells, of molecules that are involved in interactions between the epithelium and neutrophils following bacterial invasion. We report herein that expression of ICAM-1 on human colon epithelial cell lines, and on human enterocytes in an in vivo model system, is upregulated following infection with invasive bacteria. Increased ICAM-1 expression in the early period (4-9 h) after infection appeared to result mainly from a direct interaction between invaded bacteria and host epithelial cells since it co-localized to cells invaded by bacteria, and the release of soluble factors by epithelial cells played only a minor role in mediating increased ICAM-1 expression. Furthermore, ICAM-1 was expressed on the apical side of polarized intestinal epithelial cells, and increased expression was accompanied by increased neutrophil adhesion to these cells. ICAM-1 expression by intestinal epithelial cells following infection with invasive bacteria may function to maintain neutrophils that have transmigrated through the epithelium in close contact with the intestinal epithelium, thereby reducing further invasion of the mucosa by invading pathogens. PMID:8755670

  2. Tanshinone II A stabilizes vulnerable plaques by suppressing RAGE signaling and NF-κB activation in apolipoprotein-E-deficient mice

    PubMed Central

    Zhao, Dong; Tong, Lufang; Zhang, Lixin; Li, Hong; Wan, Yingxin; Zhang, Tiezhong

    2016-01-01

    Tanshinone II A (TSIIA) is a diterpene quinone extracted from the roots of Salvia miltiorrhiza with anti-inflammatory and anti-oxidant properties that is used to treat atherosclerosis. In the current study, morphological analyses were conducted to evaluate the effects of TSIIA on atherosclerotic vulnerable plaque stability. Additionally, receptor of advanced glycation end products (RAGE), adhesion molecule, and matrix-metalloproteinases (MMPs) expression, and nuclear factor-κB (NF-κB) activation were examined in apolipoprotein E (apoE)-deficient mice treated with TSIIA. Eight-week-old apoE−/− mice were administered TSIIA and fed an atherogenic diet for 8 weeks. TSIIA exhibited no effects on plaque size. Analysis of the vulnerable plaque composition demonstrated decreased numbers of macrophages and smooth muscle cells, and increased collagen content in apoE-deficient mice treated with TSIIA compared with untreated mice. Western blotting revealed that TSIIA downregulated the expression levels of vascular cellular adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and MMP-2, −3, and −9, suppressed RAGE, and inhibited NF-κB, JNK and p38 activation. The present study demonstrated that the underlying mechanism of TSIIA stabilization of vulnerable plaques involves interfering with RAGE and NF-κB activation, and downregulation of downstream inflammatory factors, including ICAM-1, VCAM-1, and MMP-2, −3 and −9 in apoE−/− mice. PMID:27840935

  3. Marathon Race Affects Neutrophil Surface Molecules: Role of Inflammatory Mediators

    PubMed Central

    2016-01-01

    The fatigue induced by marathon races was observed in terms of inflammatory and immunological outcomes. Neutrophil survival and activation are essential for inflammation resolution and contributes directly to the pathogenesis of many infectious and inflammatory conditions. The aim of this study was to investigate the effect of marathon races on surface molecules related to neutrophil adhesion and extrinsic apoptosis pathway and its association with inflammatory markers. We evaluated 23 trained male runners at the São Paulo International Marathon 2013. The following components were measured: hematological and inflammatory mediators, muscle damage markers, and neutrophil function. The marathon race induced an increased leukocyte and neutrophil counts; creatine kinase (CK), lactate dehydrogenase (LDH), CK-MB, interleukin (IL)-6, IL-10, and IL-8 levels. C-reactive protein (CRP), IL-12, and tumor necrosis factor (TNF)-α plasma concentrations were significantly higher 24 h and 72 h after the marathon race. Hemoglobin and hematocrit levels decreased 72 h after the marathon race. We also observed an increased intercellular adhesion molecule-1 (ICAM-1) expression and decreasedTNF receptor-1 (TNFR1) expression immediately after and 24 h after the marathon race. We observed an increased DNA fragmentation and L-selectin and Fas receptor expressions in the recovery period, indicating a possible slow rolling phase and delayed neutrophil activation and apoptosis. Marathon racing affects neutrophils adhesion and survival in the course of inflammation, supporting the “open-window” post-exercise hypothesis. PMID:27911915

  4. Cellular and molecular mechanisms of pomegranate juice-induced anti-metastatic effect on prostate cancer cells.

    PubMed

    Wang, Lei; Alcon, Andre; Yuan, Hongwei; Ho, Jeffrey; Li, Qi-Jing; Martins-Green, M

    2011-07-01

    Prostate cancer is the second leading cause of cancer-related deaths among US males. Pomegranate juice (PJ), a natural product, was shown in a clinical trial to inhibit progression of this disease. However, the underlying mechanisms involved in the anti-progression effects of PJ on prostate cancer remain unclear. Here we show that, in addition to causing cell death of hormone-refractory prostate cancer cells, PJ also increases cell adhesion and decreases cell migration of the cells that do not die. We hypothesized that PJ does so by stimulating the expression and/or activation of molecules that alter the cytoskeleton and the adhesion machinery of prostate cancer cells, resulting in enhanced cell adhesion and reduced cell migration. We took an integrative approach to these studies by using Affimetrix gene arrays to study gene expression, microRNA arrays to study the non-coding RNAs, molecules known to be disregulated in cancer cells, and Luminex Multiplex array assays to study the level of secreted pro-inflammatory cytokines/chemokines. PJ up-regulates genes involved in cell adhesion such as E-cadherin, intercellular adhesion molecule 1 (ICAM-1) and down-regulates genes involved in cell migration such as hyaluranan-mediated motility receptor (HMMR) and type I collagen. In addition, anti-invasive microRNAs such as miR-335, miR-205, miR-200, and miR-126, were up-regulated, whereas pro-invasive microRNA such as miR-21 and miR-373, were down-regulated. Moreover, PJ significantly reduced the level of secreted pro-inflammatory cytokines/chemokines such as IL-6, IL-12p40, IL-1β and RANTES, thereby having the potential to decrease inflammation and its impact on cancer progression. PJ also inhibits the ability of the chemokine SDF1α to chemoattract these cancer cells. SDF1α and its receptor CXCR4 are important in metastasis of cancer cells to the bone. Discovery of the mechanisms by which this enhanced adhesion and reduced migration are accomplished can lead to sophisticated and effective prevention of metastasis in prostate and potentially other cancers. This journal is © The Royal Society of Chemistry 2011

  5. EGFR and ADAMs Cooperate to Regulate Shedding and Endocytic Trafficking of the Desmosomal Cadherin Desmoglein 2

    PubMed Central

    Klessner, Jodi L.; Desai, Bhushan V.; Amargo, Evangeline V.; Getsios, Spiro

    2009-01-01

    Regulation of classic cadherins plays a critical role in tissue remodeling during development and cancer; however, less attention has been paid to the importance of desmosomal cadherins. We previously showed that EGFR inhibition results in accumulation of the desmosomal cadherin, desmoglein 2 (Dsg2), at cell–cell interfaces accompanied by inhibition of matrix metalloprotease (MMP)-dependent shedding of the Dsg2 ectodomain and tyrosine phosphorylation of its cytoplasmic domain. Here, we show that EGFR inhibition stabilizes Dsg2 at intercellular junctions by interfering with its accumulation in an internalized cytoplasmic pool. Furthermore, MMP inhibition and ADAM17 RNAi, blocked shedding and depleted internalized Dsg2, but less so E-cadherin, in highly invasive SCC68 cells. ADAM9 and 15 silencing also impaired Dsg2 processing, supporting the idea that this desmosomal cadherin can be regulated by multiple ADAM family members. In contrast, ADAM10 siRNA enhanced accumulation of a 100-kDa Dsg2 cleavage product and internalized pool of Dsg2. Although both MMP and EGFR inhibition increased intercellular adhesive strength in control cells, the response to MMP-inhibition was Dsg2-dependent. These data support a role for endocytic trafficking in regulating desmosomal cadherin turnover and function and raise the possibility that internalization and regulation of desmosomal and classic cadherin function can be uncoupled mechanistically. PMID:18987342

  6. Geometry, packing, and evolutionary paths to increased multicellular size

    NASA Astrophysics Data System (ADS)

    Jacobeen, Shane; Graba, Elyes C.; Brandys, Colin G.; Day, Thomas C.; Ratcliff, William C.; Yunker, Peter J.

    2018-05-01

    The evolutionary transition to multicellularity transformed life on earth, heralding the evolution of large, complex organisms. Recent experiments demonstrated that laboratory-evolved multicellular "snowflake yeast" readily overcome the physical barriers that limit cluster size by modifying cellular geometry [Jacobeen et al., Nat. Phys. 14, 286 (2018), 10.1038/s41567-017-0002-y]. However, it is unclear why this route to large size is observed, rather than an evolved increase in intercellular bond strength. Here, we use a geometric model of the snowflake yeast growth form to examine the geometric efficiency of increasing size by modifying geometry and bond strength. We find that changing geometry is a far more efficient route to large size than evolving increased intercellular adhesion. In fact, increasing cellular aspect ratio is on average ˜13 times more effective than increasing bond strength at increasing the number of cells in a cluster. Modifying other geometric parameters, such as the geometric arrangement of mother and daughter cells, also had larger effects on cluster size than increasing bond strength. Simulations reveal that as cells reproduce, internal stress in the cluster increases rapidly; thus, increasing bond strength provides diminishing returns in cluster size. Conversely, as cells become more elongated, cellular packing density within the cluster decreases, which substantially decreases the rate of internal stress accumulation. This suggests that geometrically imposed physical constraints may have been a key early selective force guiding the emergence of multicellular complexity.

  7. Dominant de novo DSP mutations cause erythrokeratodermia-cardiomyopathy syndrome.

    PubMed

    Boyden, Lynn M; Kam, Chen Y; Hernández-Martín, Angela; Zhou, Jing; Craiglow, Brittany G; Sidbury, Robert; Mathes, Erin F; Maguiness, Sheilagh M; Crumrine, Debra A; Williams, Mary L; Hu, Ronghua; Lifton, Richard P; Elias, Peter M; Green, Kathleen J; Choate, Keith A

    2016-01-15

    Disorders of keratinization (DOK) show marked genotypic and phenotypic heterogeneity. In most cases, disease is primarily cutaneous, and further clinical evaluation is therefore rarely pursued. We have identified subjects with a novel DOK featuring erythrokeratodermia and initially-asymptomatic, progressive, potentially fatal cardiomyopathy, a finding not previously associated with erythrokeratodermia. We show that de novo missense mutations clustered tightly within a single spectrin repeat of DSP cause this novel cardio-cutaneous disorder, which we term erythrokeratodermia-cardiomyopathy (EKC) syndrome. We demonstrate that DSP mutations in our EKC syndrome subjects affect localization of desmosomal proteins and connexin 43 in the skin, and result in desmosome aggregation, widening of intercellular spaces, and lipid secretory defects. DSP encodes desmoplakin, a primary component of desmosomes, intercellular adhesion junctions most abundant in the epidermis and heart. Though mutations in DSP are known to cause other disorders, our cohort features the unique clinical finding of severe whole-body erythrokeratodermia, with distinct effects on localization of desmosomal proteins and connexin 43. These findings add a severe, previously undescribed syndrome featuring erythrokeratodermia and cardiomyopathy to the spectrum of disease caused by mutation in DSP, and identify a specific region of the protein critical to the pathobiology of EKC syndrome and to DSP function in the heart and skin. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Detection of entrapped moisture in honeycomb sandwich structures

    NASA Technical Reports Server (NTRS)

    Hallmark, W. B.

    1967-01-01

    Thermal neutron moisture detection system detects entrapped moisture in intercellular areas of bonded honeycomb sandwich structures. A radium/beryllium fast neutron source bombards a specimen. The emitted thermal neutrons from the target nucleus are detected and counted by a boron trifluoride thermal neutron detector.

  9. An electrostatic mechanism for Ca2+-mediated regulation of gap junction channels

    PubMed Central

    Bennett, Brad C.; Purdy, Michael D.; Baker, Kent A.; Acharya, Chayan; McIntire, William E.; Stevens, Raymond C.; Zhang, Qinghai; Harris, Andrew L.; Abagyan, Ruben; Yeager, Mark

    2016-01-01

    Gap junction channels mediate intercellular signalling that is crucial in tissue development, homeostasis and pathologic states such as cardiac arrhythmias, cancer and trauma. To explore the mechanism by which Ca2+ blocks intercellular communication during tissue injury, we determined the X-ray crystal structures of the human Cx26 gap junction channel with and without bound Ca2+. The two structures were nearly identical, ruling out both a large-scale structural change and a local steric constriction of the pore. Ca2+ coordination sites reside at the interfaces between adjacent subunits, near the entrance to the extracellular gap, where local, side chain conformational rearrangements enable Ca2+chelation. Computational analysis revealed that Ca2+-binding generates a positive electrostatic barrier that substantially inhibits permeation of cations such as K+ into the pore. Our results provide structural evidence for a unique mechanism of channel regulation: ionic conduction block via an electrostatic barrier rather than steric occlusion of the channel pore. PMID:26753910

  10. Interleukin-4 and interleukin-13 compromise the sinonasal epithelial barrier and perturb intercellular junction protein expression.

    PubMed

    Wise, Sarah K; Laury, Adrienne M; Katz, Elizabeth H; Den Beste, Kyle A; Parkos, Charles A; Nusrat, Asma

    2014-05-01

    Altered expression of epithelial intercellular junction proteins has been observed in sinonasal biopsies from nasal polyps and epithelial layers cultured from nasal polyp patients. These alterations comprise a "leaky" epithelial barrier phenotype. We hypothesize that T helper 2 (Th2) cytokines interleukin (IL)-4 and IL-13 modulate epithelial junction proteins, thereby contributing to the leaky epithelial barrier. Differentiated primary sinonasal epithelial layers cultured at the air-liquid interface were exposed to IL-4, IL-13, and controls for 24 hours at 37°C. Epithelial resistance measurements were taken every 4 hours during cytokine exposure. Western blot and immunofluorescence staining/confocal microscopy were used to assess changes in a panel of tight and adherens junction proteins. Western blot densitometry was quantified with image analysis. IL-4 and IL-13 exposure resulted in a mean decrease in transepithelial resistance at 24 hours to 51.6% (n = 6) and 68.6% (n = 8) of baseline, respectively. Tight junction protein junctional adhesion molecule-A (JAM-A) expression decreased 42.2% with IL-4 exposure (n = 9) and 37.5% with IL-13 exposure (n = 9). Adherens junction protein E-cadherin expression decreased 35.3% with IL-4 exposure (n = 9) and 32.9% with IL-13 exposure (n = 9). Tight junction protein claudin-2 showed more variability but had a trend toward higher expression with Th2 cytokine exposure. There were no appreciable changes in claudin-1, occludin, or zonula occludens-1 (ZO-1) with IL-4 or IL-13 exposure. Sinonasal epithelial exposure to Th2 cytokines IL-4 and IL-13 results in alterations in intercellular junction proteins, reflecting increased epithelial permeability. Such changes may explain some of the phenotypic manifestations of Th2-mediated sinonasal disease, such as edema, nasal discharge, and environmental reactivity. © 2014 ARS-AAOA, LLC.

  11. Interacting Network of the Gap Junction (GJ) Protein Connexin43 (Cx43) is Modulated by Ischemia and Reperfusion in the Heart.

    PubMed

    Martins-Marques, Tania; Anjo, Sandra Isabel; Pereira, Paulo; Manadas, Bruno; Girão, Henrique

    2015-11-01

    The coordinated and synchronized cardiac muscle contraction relies on an efficient gap junction-mediated intercellular communication (GJIC) between cardiomyocytes, which involves the rapid anisotropic impulse propagation through connexin (Cx)-containing channels, namely of Cx43, the most abundant Cx in the heart. Expectedly, disturbing mechanisms that affect channel activity, localization and turnover of Cx43 have been implicated in several cardiomyopathies, such as myocardial ischemia. Besides gap junction-mediated intercellular communication, Cx43 has been associated with channel-independent functions, including modulation of cell adhesion, differentiation, proliferation and gene transcription. It has been suggested that the role played by Cx43 is dictated by the nature of the proteins that interact with Cx43. Therefore, the characterization of the Cx43-interacting network and its dynamics is vital to understand not only the molecular mechanisms underlying pathological malfunction of gap junction-mediated intercellular communication, but also to unveil novel and unanticipated biological functions of Cx43. In the present report, we applied a quantitative SWATH-MS approach to characterize the Cx43 interactome in rat hearts subjected to ischemia and ischemia-reperfusion. Our results demonstrate that, in the heart, Cx43 interacts with proteins related with various biological processes such as metabolism, signaling and trafficking. The interaction of Cx43 with proteins involved in gene transcription strengthens the emerging concept that Cx43 has a role in gene expression regulation. Importantly, our data shows that the interactome of Cx43 (Connexome) is differentially modulated in diseased hearts. Overall, the characterization of Cx43-interacting network may contribute to the establishment of new therapeutic targets to modulate cardiac function in physiological and pathological conditions. Data are available via ProteomeXchange with identifier PXD002331. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Biophysics of cadherin adhesion.

    PubMed

    Leckband, Deborah; Sivasankar, Sanjeevi

    2012-01-01

    Since the identification of cadherins and the publication of the first crystal structures, the mechanism of cadherin adhesion, and the underlying structural basis have been studied with a number of different experimental techniques, different classical cadherin subtypes, and cadherin fragments. Earlier studies based on biophysical measurements and structure determinations resulted in seemingly contradictory findings regarding cadherin adhesion. However, recent experimental data increasingly reveal parallels between structures, solution binding data, and adhesion-based biophysical measurements that are beginning to both reconcile apparent differences and generate a more comprehensive model of cadherin-mediated cell adhesion. This chapter summarizes the functional, structural, and biophysical findings relevant to cadherin junction assembly and adhesion. We emphasize emerging parallels between findings obtained with different experimental approaches. Although none of the current models accounts for all of the available experimental and structural data, this chapter discusses possible origins of apparent discrepancies, highlights remaining gaps in current knowledge, and proposes challenges for further study.

  13. Grippers Based on Opposing Van Der Waals Adhesive Pads

    NASA Technical Reports Server (NTRS)

    Parness, Aaron (Inventor); Kennedy, Brett A. (Inventor); Heverly, Matthew C (Inventor); Cutkosky, Mark R. (Inventor); Hawkes, Elliot Wright (Inventor)

    2016-01-01

    Novel gripping structures based on van der Waals adhesive forces are disclosed. Pads covered with fibers can be activated in pairs by opposite forces, thereby enabling control of the adhesive force in an ON or OFF state. Pads can be used in groups, each comprising a group of opposite pads. The adhesive structures enable anchoring forces that can resist adverse forces from different directions. The adhesive structures can be used to enable the operation of robots on surfaces of space vehicles.

  14. Non-contact quantification of laser micro-impulse in water by atomic force microscopy and its application for biomechanics

    NASA Astrophysics Data System (ADS)

    Hosokawa, Yoichiroh

    2011-12-01

    We developed a local force measurement system of a femtosecond laser-induced impulsive force, which is due to shock and stress waves generated by focusing an intense femtosecond laser into water with a highly numerical aperture objective lens. In this system, the force localized in micron-sized region was detected by bending movement of a cantilever of atomic force microscope (AFM). Here we calculated the bending movement of the AFM cantilever when the femtosecond laser is focused in water at the vicinity of the cantilever and the impulsive force is loaded on the cantilever. From the result, a method to estimate the total of the impulsive force at the laser focal point was suggested and applied to estimate intercellular adhesion strength.

  15. Bacterial Influences on Animal Origins

    PubMed Central

    Alegado, Rosanna A.; King, Nicole

    2014-01-01

    Animals evolved in seas teeming with bacteria, yet the influences of bacteria on animal origins are poorly understood. Comparisons among modern animals and their closest living relatives, the choanoflagellates, suggest that the first animals used flagellated collar cells to capture bacterial prey. The cell biology of prey capture, such as cell adhesion between predator and prey, involves mechanisms that may have been co-opted to mediate intercellular interactions during the evolution of animal multicellularity. Moreover, a history of bacterivory may have influenced the evolution of animal genomes by driving the evolution of genetic pathways for immunity and facilitating lateral gene transfer. Understanding the interactions between bacteria and the progenitors of animals may help to explain the myriad ways in which bacteria shape the biology of modern animals, including ourselves. PMID:25280764

  16. Failure of physiologic transformation of spiral arteries, endothelial and trophoblast cell activation, and acute atherosis in the basal plate of the placenta

    PubMed Central

    Labarrere, Carlos A.; DiCarlo, Hector L.; Bammerlin, Elaine; Hardin, James W.; Kim, Yeon Mee; Chaemsaithong, Piya; Haas, David M.; Kassab, Ghassan S.; Romero, Roberto

    2018-01-01

    Background Failure of physiologic transformation of spiral arteries has been reported in preeclampsia, fetal growth restriction, fetal death, and spontaneous preterm labor with intact or ruptured membranes. Spiral arteries with failure of physiologic transformation are prone to develop atherosclerotic-like lesions of atherosis. There are striking parallels between preeclampsia and atherosclerotic disease, and between lesions of atherosis and atherosclerosis. Endothelial activation, identified by intercellular adhesion molecule-1 expression, is present in atherosclerotic-like lesions of heart transplantation and considered a manifestation of rejection. Similarly, endothelial activation/dysfunction has been implicated in the pathophysiology of atherosclerosis and preeclampsia. Intercellular adhesion molecule-1-overexpressing-activated endothelial cells are more resistant to trophoblast displacement than nonactivated endothelium and may contribute to shallow spiral artery trophoblastic invasion in obstetrical syndromes having failure of physiologic transformation. Objective To determine whether failure of spiral artery physiologic transformation was associated with activation of interstitial extravillous trophoblasts and/or spiral artery endothelium and presence of acute atherosis in the placental basal plate. Study Design A cross-sectional study of 123 placentas (19-42 weeks’ gestation) obtained from normal pregnancies (n = 22), preterm prelabor rupture of membranes (n = 26), preterm labor (n = 23), preeclampsia (n = 27), intrauterine fetal death (n = 15), and small for gestational age (n = 10) was performed. Failure of spiral artery physiologic transformation and presence of cell activation was determined using immunohistochemistry of placental basal plates containing a median of 4 (minimum: 1; maximum: 9) vessels per placenta. Endothelial/trophoblast cell activation was defined by the expression of intercellular adhesion molecule-1 (ICAM-1). Investigators examining microscopic sections were blinded to clinical diagnosis. Pairwise comparisons among placenta groups were performed with the Fisher’s exact and Wilcoxon rank sum tests using a Bonferroni-adjusted level of significance (.025). Results 87% (94/108) of placentas having spiral arteries with failure of physiologic transformation (actin-positive and cytokeratin-negative) in the basal plate, and 0% (0/15) of placentas having only spiral arteries with complete physiologic transformation (cytokeratin-positive and actin-negative), had arterial endothelial and/or interstitial extravillous trophoblasts reactive with the ICAM-1 activation marker (P < .001). A significant correlation (R2 = 0.84) was found between expression of spiral artery endothelial and interstitial extravillous trophoblast ICAM-1 (P < .001) in activated placentas. Lesions of atherosis were found in 31.9% (30/94) of placentas with complete and/or partial failure of physiologic transformation of spiral arteries that were ICAM-1-positive, in none of the 14 placentas with failure of physiologic transformation that were ICAM-1-negative, and in none of the 15 placentas with complete spiral artery physiologic transformation without failure (P = .001). All placentas (30/30, 100%) with atherosis were identified in placentas having concomitant spiral artery endothelial and interstitial extravillous trophoblast activation. Conclusion Failure of spiral artery physiologic transformation in the placental basal plate is associated with interstitial extravillous trophoblast and arterial endothelial activation along with increased frequency of spiral artery atherosis. These findings may be used to improve the characterization of different disorders of the placental bed such as in refining the existing tools for the early prediction of risk for preterm, preeclamptic, and other abnormal pregnancies. PMID:28034657

  17. Improved Adhesion and Compliancy of Hierarchical Fibrillar Adhesives.

    PubMed

    Li, Yasong; Gates, Byron D; Menon, Carlo

    2015-08-05

    The gecko relies on van der Waals forces to cling onto surfaces with a variety of topography and composition. The hierarchical fibrillar structures on their climbing feet, ranging from mesoscale to nanoscale, are hypothesized to be key elements for the animal to conquer both smooth and rough surfaces. An epoxy-based artificial hierarchical fibrillar adhesive was prepared to study the influence of the hierarchical structures on the properties of a dry adhesive. The presented experiments highlight the advantages of a hierarchical structure despite a reduction of overall density and aspect ratio of nanofibrils. In contrast to an adhesive containing only nanometer-size fibrils, the hierarchical fibrillar adhesives exhibited a higher adhesion force and better compliancy when tested on an identical substrate.

  18. Mechanisms and regulation of polymorphonuclear leukocyte and eosinophil adherence to human airway epithelial cells.

    PubMed

    Jagels, M A; Daffern, P J; Zuraw, B L; Hugli, T E

    1999-09-01

    Polymorphonuclear leukocytes (PMN) and eosinophils (Eos) are important cellular participants in a variety of acute and chronic inflammatory reactions in the airway. Histologic evidence has implicated direct interactions between these two subsets of leukocytes and airway epithelial cells during inflammation. A comprehensive characterization and comparison of physiologic stimuli and adhesion molecule involvement in granulocyte-epithelial-cell interactions done with nontransformed human airway epithelial cells has not been reported. We therefore examined the regulation and biochemical mechanisms governing granulocyte-epithelial-cell adhesion, using either purified PMN or Eos and primary cultures of human bronchial epithelial cells (HBECs). We investigated the involvement of a number of proinflammatory signals associated with allergic and nonallergic airway inflammation, as well as the contribution of several epithelial and leukocyte adhesion molecules, including intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and members of the beta(1), beta(2), and beta(7) integrin families. ICAM-1 was expressed at low levels on cultured HBECs and was markedly upregulated after stimulation with interferon (IFN)-gamma or, to a lesser extent, with tumor necrosis factor (TNF)-alpha or interleukin (IL)-1. VCAM-1 was not present on resting HBECs, and was not upregulated after stimulation with IFN-gamma, IL-1, IL-4, or TNF-alpha. PMN adhesion to HBECs could be induced either through activation of PMN with IL-8, granulocyte-macrophage colony-stimulating factor (GM-CSF), or C5a, but not with IL-5 or by preactivation of HBECs with TNF-alpha or IFN-gamma. Blocking antibody studies indicated that PMN-HBEC adherence depended on beta(2) integrins, primarily alpha(M)beta(2) (Mac-1). Adherence of Eos to HBECs could be induced through activation of Eos with IL-5, GM-CSF, or C5a, but not with IL-8 or by prior activation of HBECs with TNF-alpha of IFN-gamma. Maximal adhesion of Eos and PMN required pretreatment of HBECs with either TNF-alpha or IFN-gamma in addition to leukocyte activation. Adherence of Eos to unstimulated HBECs was mediated through both beta(1) and beta(2) integrins, whereas adhesion of Eos to activated HBECs was dominated by beta(2) integrins. Adhesion of both Eos and PMN was inhibited by treatment of HBECs with blocking antibodies to ICAM-1. Differential utilization of beta(1) and beta(2) integrins by Eos, depending on the activation state of the epithelium, is a novel finding and may affect activation and/or recruitment of Eos in airway tissue. Mechanisms of adhesion of HBECs to Eos and PMN, as evidenced by the different responsiveness of the two latter types of cells to IL-8 and IL-5, may account for a prevalence of Eos over PMN in certain airway diseases.

  19. Intrinsically disordered proteins aggregate at fungal cell-to-cell channels and regulate intercellular connectivity

    PubMed Central

    Lai, Julian; Koh, Chuan Hock; Tjota, Monika; Pieuchot, Laurent; Raman, Vignesh; Chandrababu, Karthik Balakrishna; Yang, Daiwen; Wong, Limsoon; Jedd, Gregory

    2012-01-01

    Like animals and plants, multicellular fungi possess cell-to-cell channels (septal pores) that allow intercellular communication and transport. Here, using a combination of MS of Woronin body-associated proteins and a bioinformatics approach that identifies related proteins based on composition and character, we identify 17 septal pore-associated (SPA) proteins that localize to the septal pore in rings and pore-centered foci. SPA proteins are not homologous at the primary sequence level but share overall physical properties with intrinsically disordered proteins. Some SPA proteins form aggregates at the septal pore, and in vitro assembly assays suggest aggregation through a nonamyloidal mechanism involving mainly α-helical and disordered structures. SPA loss-of-function phenotypes include excessive septation, septal pore degeneration, and uncontrolled Woronin body activation. Together, our data identify the septal pore as a complex subcellular compartment and focal point for the assembly of unstructured proteins controlling diverse aspects of intercellular connectivity. PMID:22955885

  20. CO₂ processing and hydration of fruit and vegetable tissues by clathrate hydrate formation.

    PubMed

    Takeya, Satoshi; Nakano, Kohei; Thammawong, Manasikan; Umeda, Hiroki; Yoneyama, Akio; Takeda, Tohoru; Hyodo, Kazuyuki; Matsuo, Seiji

    2016-08-15

    CO2 hydrate can be used to preserve fresh fruits and vegetables, and its application could contribute to the processing of carbonated frozen food. We investigated water transformation in the frozen tissue of fresh grape samples upon CO2 treatment at 2-3 MPa and 3°C for up to 46 h. Frozen fresh bean, radish, eggplant and cucumber samples were also investigated for comparison. X-ray diffraction indicated that after undergoing CO2 treatment for several hours, structure I CO2 hydrate formed within the grape tissue. Phase-contrast X-ray imaging using the diffraction-enhanced imaging technique revealed the presence of CO2 hydrate within the intercellular spaces of these tissues. The carbonated produce became effervescent because of the dissociation of CO2 hydrate through the intercellular space, especially above the melting point of ice. In addition, suppressed metabolic activity resulting from CO2 hydrate formation, which inhibits water and nutrient transport through intercellular space, can be expected. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Joining Tubes With Adhesive

    NASA Technical Reports Server (NTRS)

    Bateman, W. A.

    1984-01-01

    Cylindrical tubes joined together, end to end, by method employing adhesive, tapered ends, and spacing wires. Tapered joint between tubular structural elements provides pressure between bonding surfaces during adhesive curing. Spacing wires prevent adhesive from being scraped away when one element inserted in other. Method developed for assembling structural elements made of composite materials.

  2. Evaluation of high temperature structural adhesives for extended service, phase 5

    NASA Technical Reports Server (NTRS)

    Hendricks, C. L.; Hill, S. G.; Hale, J. N.; Dumars, W. G.

    1987-01-01

    The evaluation of 3 experimental polymers from NASA-Langley and a commercially produced polymer from Mitsui Toatsu Chemicals as high temperature structural adhesives is presented. A polyphenylquinoxaline (PPQ), polyimide (STPI/LaRC-2), and a polyarylene ether (PAE-SO2) were evaluated as metal-to-metal adhesives. Lap shear, crack extension, and climbing drum peel specimens were fabricated from all three polymers and tested after thermal, combined thermal/humidity, and stressed hydraulic fluid (Skydrol) exposure. The fourth polymer, LARC-TPI was evaluated as an adhesive for titanium honeycomb sandwich structure. All three experimental polymers performed well as metal-to-metal adhesives from 219 K (-65 F) to 505 K (450 F), including humidity exposure. Structural adhesive strength was also maintained at 505 K for a minimum of 3000 hours. LaRC-TPI was evaluated as a high temperature (505 K) adhesive for titanium honeycomb sandwich structure. The LaRC-TPI bonding process development concentrated on improving the honeycomb core-to-skin bond. The most promising approach of those evaluated combined a LaRC-TPI polymer solution with a semi-crystalline LaRC-TPI powder for adhesive film fabrication and fillet formation.

  3. High plasma levels of soluble intercellular adhesion molecule (ICAM)-1 are associated with cerebral malaria.

    PubMed

    Adukpo, Selorme; Kusi, Kwadwo A; Ofori, Michael F; Tetteh, John K A; Amoako-Sakyi, Daniel; Goka, Bamenla Q; Adjei, George O; Edoh, Dominic A; Akanmori, Bartholomew D; Gyan, Ben A; Dodoo, Daniel

    2013-01-01

    Cerebral malaria (CM) is responsible for most of the malaria-related deaths in children in sub-Saharan Africa. Although, not well understood, the pathogenesis of CM involves parasite and host factors which contribute to parasite sequestration through cytoadherence to the vascular endothelium. Cytoadherence to brain microvasculature is believed to involve host endothelial receptor, CD54 or intercellular adhesion molecule (ICAM)-1, while other receptors such as CD36 are generally involved in cytoadherence of parasites in other organs. We therefore investigated the contributions of host ICAM-1 expression and levels of antibodies against ICAM-1 binding variant surface antigen (VSA) on parasites to the development of CM. Paediatric malaria patients, 0.5 to 13 years were recruited and grouped into CM and uncomplicated malaria (UM) patients, based on well defined criteria. Standardized ELISA protocol was used to measure soluble ICAM-1 (sICAM-1) levels from acute plasma samples. Levels of IgG to CD36- or ICAM-1-binding VSA were measured by flow cytometry during acute and convalescent states. Wilcoxon sign rank-test analysis to compare groups revealed association between sICAM-1 levels and CM (p<0.0037). Median levels of antibodies to CD36-binding VSA were comparable in the two groups at the time of admission and 7 days after treatment was initiated (p>0.05). Median levels of antibodies to CD36-binding VSAs were also comparable between acute and convalescent samples within any patient group. Median levels of antibodies to ICAM-1-binding VSAs were however significantly lower at admission time than during recovery in both groups. High levels of sICAM-1 were associated with CM, and the sICAM-1 levels may reflect expression levels of the membrane bound form. Anti-VSA antibody levels to ICAM-binding parasites was more strongly associated with both UM and CM than antibodies to CD36 binding parasites. Thus, increasing host sICAM-1 levels were associated with CM whilst antibodies to parasite expressing non-ICAM-1-binding VSAs were not.

  4. Novel Metrics to Characterize Embryonic Elongation of the Nematode Caenorhabditis elegans.

    PubMed

    Martin, Emmanuel; Rocheleau-Leclair, Olivier; Jenna, Sarah

    2016-03-28

    Dissecting the signaling pathways that control the alteration of morphogenic processes during embryonic development requires robust and sensitive metrics. Embryonic elongation of the nematode Caenorhabditis elegans is a late developmental stage consisting of the elongation of the embryo along its longitudinal axis. This developmental stage is controlled by intercellular communication between hypodermal cells and underlying body-wall muscles. These signaling mechanisms control the morphology of hypodermal cells by remodeling the cytoskeleton and the cell-cell junctions. Measurement of embryonic lethality and developmental arrest at larval stages as well as alteration of cytoskeleton and cell-cell adhesion structures in hypodermal and muscle cells are classical phenotypes that have been used for more than 25 years to dissect these signaling pathways. Recent studies required the development of novel metrics specifically targeting either early or late elongation and characterizing morphogenic defects along the antero-posterior axis of the embryo. Here, we provide detailed protocols enabling the accurate measurement of the length and the width of the elongating embryos as well as the length of synchronized larvae. These methods constitute useful tools to identify genes controlling elongation, to assess whether these genes control both early and late phases of this stage and are required evenly along the antero-posterior axis of the embryo.

  5. Lactobacillus casei BL23 Produces Microvesicles Carrying Proteins That Have Been Associated with Its Probiotic Effect

    PubMed Central

    Domínguez Rubio, A. Paula; Martínez, Jimena H.; Martínez Casillas, Diana C.; Coluccio Leskow, Federico; Piuri, Mariana; Pérez, Oscar E.

    2017-01-01

    Archaea, bacteria, and eukarya secrete membrane microvesicles (MVs) as a mechanism for intercellular communication. We report the isolation and characterization of MVs from the probiotic strain Lactobacillus casei BL23. MVs were characterized using analytical high performance techniques, DLS, AFM and TEM. Similar to what has been described for other Gram-positive bacteria, MVs were on the nanometric size range (30–50 nm). MVs carried cytoplasmic components such as DNA, RNA and proteins. Using a proteomic approach (LC-MS), we identified a total of 103 proteins; 13 exclusively present in the MVs. The MVs content included cell envelope associated and secretory proteins, heat and cold shock proteins, several metabolic enzymes, proteases, structural components of the ribosome, membrane transporters, cell wall-associated hydrolases and phage related proteins. In particular, we identified proteins described as mediators of Lactobacillus’ probiotic effects such as p40, p75 and the product of LCABL_31160, annotated as an adhesion protein. The presence of these proteins suggests a role for the MVs in the bacteria-gastrointestinal cells interface. The expression and further encapsulation of proteins into MVs of GRAS (Generally Recognized as Safe) bacteria could represent a scientific novelty, with applications in food, nutraceuticals and clinical therapies. PMID:28979244

  6. Protective effects of intercalated disk protein afadin on chronic pressure overload-induced myocardial damage

    PubMed Central

    Zankov, Dimitar P.; Shimizu, Akio; Tanaka-Okamoto, Miki; Miyoshi, Jun; Ogita, Hisakazu

    2017-01-01

    Adhesive intercellular connections at cardiomyocyte intercalated disks (IDs) support contractile force and maintain structural integrity of the heart muscle. Disturbances of the proteins at IDs deteriorate cardiac function and morphology. An adaptor protein afadin, one of the components of adherens junctions, is expressed ubiquitously including IDs. At present, the precise role of afadin in cardiac physiology or disease is unknown. To explore this, we generated conditional knockout (cKO) mice with cardiomyocyte-targeted deletion of afadin. Afadin cKO mice were born according to the expected Mendelian ratio and have no detectable changes in cardiac phenotype. On the other hand, chronic pressure overload induced by transverse aortic constriction (TAC) caused systolic dysfunction, enhanced fibrogenesis and apoptosis in afadin cKO mice. Afadin deletion increased macrophage infiltration and monocyte chemoattractant protein-1 expression, and suppressed transforming growth factor (TGF) β receptor signaling early after TAC procedure. Afadin also associated with TGFβ receptor I at IDs. Pharmacological antagonist of TGFβ receptor I (SB431542) augmented mononuclear infiltration and fibrosis in the hearts of TAC-operated control mice. In conclusion, afadin is a critical molecule for cardiac protection against chronic pressure overload. The beneficial effects are likely to be a result from modulation of TGFβ receptor signaling pathways by afadin. PMID:28045017

  7. Protein Equilibration through Somatic Ring Canals in Drosophila

    PubMed Central

    McLean, Peter F.; Cooley, Lynn

    2013-01-01

    Although intercellular bridges resulting from incomplete cytokinesis were discovered in somatic Drosophila tissues decades ago, the impact of these structures on intercellular communication and tissue biology is largely unknown. In this work, we demonstrate that the ~250 nm diameter somatic ring canals permit diffusion of cytoplasmic contents between connected cells and across mitotic clone boundaries, and enable the equilibration of protein between transcriptionally mosaic follicle cells in the Drosophila ovary. We obtained similar, though more restricted, results in the larval imaginal discs. Our work illustrates the lack of cytoplasmic autonomy in these tissues and suggests a role for somatic ring canals in promoting homogeneous protein expression within the tissue. PMID:23704373

  8. Fabrication of biomimetic dry-adhesion structures through nanosphere lithography

    NASA Astrophysics Data System (ADS)

    Kuo, P. C.; Chang, N. W.; Suen, Y.; Yang, S. Y.

    2018-03-01

    Components with surface nanostructures suitable for biomimetic dry adhesion have a great potential in applications such as gecko tape, climbing robots, and skin patches. In this study, a nanosphere lithography technique with self-assembly nanospheres was developed to achieve effective and efficient fabrication of dry-adhesion structures. Self-assembled monolayer nanospheres with high regularity were obtained through tilted dip-coating. Reactive-ion etching of the self-assembled nanospheres was used to fabricate nanostructures of different shapes and aspect ratios by varying the etching time. Thereafter, nickel molds with inverse nanostructures were replicated using the electroforming process. Polydimethylsiloxane (PDMS) nanostructures were fabricated through a gas-assisted hot-embossing method. The pulling test was performed to measure the shear adhesion on the glass substrate of a sample, and the static contact angle was measured to verify the hydrophobic property of the structure. The enhancement of the structure indicates that the adhesion force increased from 1.2 to 4.05 N/cm2 and the contact angle increased from 118.6° to 135.2°. This columnar structure can effectively enhance the adhesion ability of PDMS, demonstrating the potential of using nanosphere lithography for the fabrication of adhesive structures.

  9. Heterogeneity of Focal Adhesions and Focal Contacts in Motile Fibroblasts.

    PubMed

    Gladkikh, Aleena; Kovaleva, Anastasia; Tvorogova, Anna; Vorobjev, Ivan A

    2018-01-01

    Cell-extracellular matrix (ECM) adhesion is an important property of virtually all cells in multicellular organisms. Cell-ECM adhesion studies, therefore, are very significant both for biology and medicine. Over the last three decades, biomedical studies resulted in a tremendous advance in our understanding of the molecular basis and functions of cell-ECM adhesion. Based on morphological and molecular criteria, several different types of model cell-ECM adhesion structures including focal adhesions, focal complexes, fibrillar adhesions, podosomes, and three-dimensional matrix adhesions have been described. All the subcellular structures that mediate cell-ECM adhesion are quite heterogeneous, often varying in size, shape, distribution, dynamics, and, to a certain extent, molecular constituents. The morphological "plasticity" of cell-ECM adhesion perhaps reflects the needs of cells to sense, adapt, and respond to a variety of extracellular environments. In addition, cell type (e.g., differentiation status, oncogenic transformation, etc.) often exerts marked influence on the structure of cell-ECM adhesions. Although molecular, genetic, biochemical, and structural studies provide important maps or "snapshots" of cell-ECM adhesions, the area of research that is equally valuable is to study the heterogeneity of FA subpopulations within cells. Recently time-lapse observations on the FA dynamics become feasible, and behavior of individual FA gives additional information on cell-ECM interactions. Here we describe a robust method of labeling of FA using plasmids with fluorescent markers for paxillin and vinculin and quantifying the morphological and dynamical parameters of FA.

  10. Lipid composition of the stratum corneum and cutaneous water loss in birds along an aridity gradient.

    PubMed

    Champagne, Alex M; Muñoz-Garcia, Agustí; Shtayyeh, Tamer; Tieleman, B Irene; Hegemann, Arne; Clement, Michelle E; Williams, Joseph B

    2012-12-15

    Intercellular and covalently bound lipids within the stratum corneum (SC), the outermost layer of the epidermis, are the primary barrier to cutaneous water loss (CWL) in birds. We compared CWL and intercellular SC lipid composition in 20 species of birds from desert and mesic environments. Furthermore, we compared covalently bound lipids with CWL and intercellular lipids in the lark family (Alaudidae). We found that CWL increases in birds from more mesic environments, and this increase was related to changes in intercellular SC lipid composition. The most consistent pattern that emerged was a decrease in the relative amount of cerebrosides as CWL increased, a pattern that is counterintuitive based on studies of mammals with Gaucher disease. Although covalently bound lipids in larks did not correlate with CWL, we found that covalently bound cerebrosides correlated positively with intercellular cerebrosides and intercellular cholesterol ester, and intercellular cerebrosides correlated positively with covalently bound free fatty acids. Our results led us to propose a new model for the organization of lipids in the avian SC, in which the sugar moieties of cerebrosides lie outside of intercellular lipid layers, where they may interdigitate with adjacent intercellular cerebrosides or with covalently bound cerebrosides.

  11. Signaling from the Podocyte Intercellular Junction to the Actin Cytoskeleton

    PubMed Central

    George, Britta; Holzman, Lawrence B.

    2012-01-01

    Observations of hereditary glomerular disease support the contention that podocyte intercellular junction proteins are essential for junction formation and maintenance. Genetic deletion of most of these podocyte intercellular junction proteins results in foot process effacement and proteinuria. This review focuses on the current understanding of molecular mechanisms by which podocyte intercellular junction proteins such as the Nephrin-Neph1-Podocin receptor complex coordinate cytoskeletal dynamics and thus intercellular junction formation, maintenance and injury-dependent remodeling. PMID:22958485

  12. Cavitation of intercellular spaces is critical to establishment of hydraulic properties of compression wood of Chamaecyparis obtusa seedlings

    PubMed Central

    Nakaba, Satoshi; Hirai, Asami; Kudo, Kayo; Yamagishi, Yusuke; Yamane, Kenichi; Kuroda, Katsushi; Nugroho, Widyanto Dwi; Kitin, Peter; Funada, Ryo

    2016-01-01

    Background and Aims When the orientation of the stems of conifers departs from the vertical as a result of environmental influences, conifers form compression wood that results in restoration of verticality. It is well known that intercellular spaces are formed between tracheids in compression wood, but the function of these spaces remains to be clarified. In the present study, we evaluated the impact of these spaces in artificially induced compression wood in Chamaecyparis obtusa seedlings. Methods We monitored the presence or absence of liquid in the intercellular spaces of differentiating xylem by cryo-scanning electron microscopy. In addition, we analysed the relationship between intercellular spaces and the hydraulic properties of the compression wood. Key Results Initially, we detected small intercellular spaces with liquid in regions in which the profiles of tracheids were not rounded in transverse surfaces, indicating that the intercellular spaces had originally contained no gases. In the regions where tracheids had formed secondary walls, we found that some intercellular spaces had lost their liquid. Cavitation of intercellular spaces would affect hydraulic conductivity as a consequence of the induction of cavitation in neighbouring tracheids. Conclusions Our observations suggest that cavitation of intercellular spaces is the critical event that affects not only the functions of intercellular spaces but also the hydraulic properties of compression wood. PMID:26818592

  13. Structure-property relationships in low-temperature adhesives. [for inflatable structures

    NASA Technical Reports Server (NTRS)

    Schoff, C. K.; Udipi, K.; Gillham, J. K.

    1977-01-01

    Adhesive materials of aliphatic polyester, linear hydroxyl end-capped polybutadienes, or SBS block copolymers are studied with the objective to replace conventional partially aromatic end-reactive polyester-isocyanate adhesives that have shown embrittlement

  14. Adhesives in Building--Lamination of Structural Timber Beams, Bonding of Cementitious Materials, Bonding of Gypsum Drywall Construction. Proceedings of a Conference of the Building Research Institute, Division of Engineering and Industrial Research (Spring 1960).

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC.

    The role of adhesives in building design is discussed. Three major areas are as follows--(1) lamination of structural timber beams, (2) bonding of cementitious materials, and (3) bonding of gypsum drywall construction. Topical coverage includes--(1) structural lamination today, (2) adhesives in use today, (3) new adhesives needed, (4) production…

  15. Serum Markers of Endothelial Dysfunction and Inflammation Increase in Hypertension with Prediabetes Mellitus.

    PubMed

    Huang, Zhouqing; Chen, Chen; Li, Sheng; Kong, Fanqi; Shan, Peiren; Huang, Weijian

    2016-06-01

    The aim of this study was to examine endothelial dysfunction and inflammation in hypertension and prediabetes by studying adhesion molecules and inflammatory factors. This study included 133 outpatients. Participants were categorized into three groups based on the presence or absence of hypertension and prediabetes: control subjects without prediabetes and hypertension (N group, n = 39); patients with hypertension only (H group, n = 34); and patients with hypertension and prediabetes (HD group, n = 60). Hypertension was diagnosed according to JNC7 criteria. Prediabetes was defined according to 2010 American Diabetes Association criteria. Plasma was isolated from overnight fasting blood samples for enzyme-linked immunosorbent assay (ELISA) analysis of concentrations of intercellular adhesion molecule-1 (ICAM-1), tumor necrosis factor-α (TNF-α), P-selectin, and interleukin-6 (IL-6) as indicators of endothelial function and inflammation. We found that the H and HD groups showed significantly higher levels of all four biomarkers compared with the N group (all p < 0.01). The HD group also showed significantly higher levels of ICAM-1 (p = 0.042) and TNF-α (p < 0.01) compared with the H group; no significant differences in P-selectin (p = 0.59) and IL-6 (p = 0.70) levels were observed among these groups. Prediabetes and hypertension induce endothelial dysfunction and inflammation by elevating levels of soluble adhesion molecules and inflammatory cytokines. The comorbidity of these diseases may exacerbate inflammation and endothelial dysfunction by enhancing the expression of ICAM-1 and TNF-α.

  16. Effect of high-glucose conditions on human periodontal ligament endothelial cells: in vitro analysis.

    PubMed

    Maruyama, Kosuke; Sato, Soh

    2017-01-01

    Endothelial cells participate in key aspects of vascular biology, such as maintenance of capillary permeability and regulation of inflammation. According to previous reports, endothelial cells have revealed highly specific characteristics depending on the organs and tissues. In particular, periodontal endothelial cells have a higher permeability than vascular endothelial cells of other types of tissue. Periodontal disease is not only a chronic disease in oral, but also affect the entire body. Diabetes and periodontal disease are closely related, with periodontal disease even been referred to as the sixth complication of disease. However, no reports have investigated the pathophysiology of microvascular in periodontal tissue once diabetes has developed. Therefore, the aim of the present study is to investigate changes in the properties of human periodontal endothelial cells (HPDLECs) that were cultured under high-glucose conditions. We isolated HPDLECs from human periodontal ligament cells. HPDLECs were cultured under high-glucose (5.5, 11.0, 22.0 mM) and investigated proliferation, apoptosis, tube formation and the expression of cell adhesion molecules. A 5.5 mM (100 mg/dl) control was used in this study. HPDLECs stimulated with high glucose concentration exhibited suppression of cell proliferation and an increased percentage of apoptosis-positive cells. This results suggested that apoptosis was caused by TNF-α expression. The expression levels cell adhesion molecules increased. These results suggest that when HPDLECs are stimulated with a high glucose concentrations, PKC in the intracellular cell substrate is activated, increasing the expression of intercellular and vascular adhesion molecules. Thus, the results of this study demonstrate that diabetes exacerbates periodontal disease.

  17. Platelet activation by Histophilus somni and its lipooligosaccharide induces endothelial cell proinflammatory responses and platelet internalization.

    PubMed

    Kuckleburg, Christopher J; McClenahan, Dave J; Czuprynski, Charles J

    2008-02-01

    Histophilus somni is a gram-negative coccobacillus that causes respiratory and reproductive disease in cattle. The hallmark of systemic H. somni infection is diffuse vascular inflammation that can lead to an acute central nervous system disease known as thrombotic meningoencephalitis. Previously, we demonstrated that H. somni and its lipooligosaccharide (LOS) activate bovine platelets, leading to expression of P selectin, CD40L, and FasL. Because activated platelets have been reported to induce endothelial cell cytokine production and adhesion molecule expression, we sought to determine if bovine platelets induce proinflammatory and procoagulative changes in bovine pulmonary artery endothelial cells. Endothelial cells were incubated with platelets activated with adenosine diphosphate, H. somni, or H. somni LOS. Incubation with activated bovine platelets significantly increased expression of in adhesion molecules (intercellular adhesion molecule 1, E selectin) and tissue factor, as measured by flow cytometry, real-time polymerase chain reaction, and Western blot analysis. Activated platelets also up-regulated expression of endothelial cell IL-1beta, monocyte chemoattractant protein 1, and macrophage inflammatory protein 1alpha as determined by real-time polymerase chain reaction and an IL-1beta enzyme-linked immunosorbent assay. An interesting and surprising finding was that bovine platelets activated by H. somni or its LOS were internalized by bovine endothelial cells as visualized by transmission electron microscopy. This internalization seemed to correlate with endothelial cell activation and morphological changes indicative of cell stress. These findings suggest that activated platelets might play a role in promoting vascular inflammation during H. somni infection.

  18. The structure of cell-matrix adhesions: the new frontier.

    PubMed

    Hanein, Dorit; Horwitz, Alan Rick

    2012-02-01

    Adhesions between the cell and the extracellular matrix (ECM) are mechanosensitive multi-protein assemblies that transmit force across the cell membrane and regulate biochemical signals in response to the chemical and mechanical environment. These combined functions in force transduction, signaling and mechanosensing contribute to cellular phenotypes that span development, homeostasis and disease. These adhesions form, mature and disassemble in response to actin organization and physical forces that originate from endogenous myosin activity or external forces by the extracellular matrix. Despite advances in our understanding of the protein composition, interactions and regulation, our understanding of matrix adhesion structure and organization, how forces affect this organization, and how these changes dictate specific signaling events is limited. Insights across multiple structural levels are acutely needed to elucidate adhesion structure and ultimately the molecular basis of signaling and mechanotransduction. Here we describe the challenges and recent advances and prospects for unraveling the structure of cell-matrix adhesions and their response to force. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Development of the PANVAC-VF vaccine for pancreatic cancer.

    PubMed

    Petrulio, Christian A; Kaufman, Howard L

    2006-02-01

    PANVAC-VF is a vaccine regimen composed of a priming dose of recombinant vaccinia virus and booster doses of recombinant fowlpox virus expressing carcinoembryonic antigen, mucin-1 and a triad of costimulatory molecules (TRICOM), which include B7.1, intercellular adhesion molecule-1 and leukocyte function-associated antigen-3. Vaccination is administered by subcutaneous injection followed by 4 days of local recombinant adjuvant granulocyte-macrophage colony-stimulating factor at the vaccination site. The vaccine has been developed for patients with advanced pancreatic cancer and has now entered a randomized Phase III clinical trial. This review will describe the background of recombinant poxvirus technology for tumor vaccine development, detail the key preclinical studies supporting the regimen, review the clinical trials supporting the current Phase III study, and highlight the key challenges and future obstacles to successful implementation of PANVAC-VF for pancreatic cancer.

  20. The Peptidoglycan-Binding Protein SjcF1 Influences Septal Junction Function and Channel Formation in the Filamentous Cyanobacterium Anabaena.

    PubMed

    Rudolf, Mareike; Tetik, Nalan; Ramos-León, Félix; Flinner, Nadine; Ngo, Giang; Stevanovic, Mara; Burnat, Mireia; Pernil, Rafael; Flores, Enrique; Schleiff, Enrico

    2015-06-30

    Filamentous, heterocyst-forming cyanobacteria exchange nutrients and regulators between cells for diazotrophic growth. Two alternative modes of exchange have been discussed involving transport either through the periplasm or through septal junctions linking adjacent cells. Septal junctions and channels in the septal peptidoglycan are likely filled with septal junction complexes. While possible proteinaceous factors involved in septal junction formation, SepJ (FraG), FraC, and FraD, have been identified, little is known about peptidoglycan channel formation and septal junction complex anchoring to the peptidoglycan. We describe a factor, SjcF1, involved in regulation of septal junction channel formation in the heterocyst-forming cyanobacterium Anabaena sp. strain PCC 7120. SjcF1 interacts with the peptidoglycan layer through two peptidoglycan-binding domains and is localized throughout the cell periphery but at higher levels in the intercellular septa. A strain with an insertion in sjcF1 was not affected in peptidoglycan synthesis but showed an altered morphology of the septal peptidoglycan channels, which were significantly wider in the mutant than in the wild type. The mutant was impaired in intercellular exchange of a fluorescent probe to a similar extent as a sepJ deletion mutant. SjcF1 additionally bears an SH3 domain for protein-protein interactions. SH3 binding domains were identified in SepJ and FraC, and evidence for interaction of SjcF1 with both SepJ and FraC was obtained. SjcF1 represents a novel protein involved in structuring the peptidoglycan layer, which links peptidoglycan channel formation to septal junction complex function in multicellular cyanobacteria. Nonetheless, based on its subcellular distribution, this might not be the only function of SjcF1. Cell-cell communication is central not only for eukaryotic but also for multicellular prokaryotic systems. Principles of intercellular communication are well established for eukaryotes, but the mechanisms and components involved in bacteria are just emerging. Filamentous heterocyst-forming cyanobacteria behave as multicellular organisms and represent an excellent model to study prokaryotic cell-cell communication. A path for intercellular metabolite exchange appears to involve transfer through molecular structures termed septal junctions. They are reminiscent of metazoan gap junctions that directly link adjacent cells. In cyanobacteria, such structures need to traverse the peptidoglycan layers in the intercellular septa of the filament. Here we describe a factor involved in the formation of channels across the septal peptidoglycan layers, thus contributing to the multicellular behavior of these organisms. Copyright © 2015 Rudolf et al.

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