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Sample records for adhesion molecule inhibitors

  1. Suppression of complement regulatory protein C1 inhibitor in vascular endothelial activation by inhibiting vascular cell adhesion molecule-1 action

    SciTech Connect

    Zhang, Haimou; Qin, Gangjian; Liang, Gang; Li, Jinan; Chiu, Isaac; Barrington, Robert A.; Liu, Dongxu . E-mail: dxliu001@yahoo.com

    2007-07-13

    Increased expression of adhesion molecules by activated endothelium is a critical feature of vascular inflammation associated with the several diseases such as endotoxin shock and sepsis/septic shock. Our data demonstrated complement regulatory protein C1 inhibitor (C1INH) prevents endothelial cell injury. We hypothesized that C1INH has the ability of an anti-endothelial activation associated with suppression of expression of adhesion molecule(s). C1INH blocked leukocyte adhesion to endothelial cell monolayer in both static assay and flow conditions. In inflammatory condition, C1INH reduced vascular cell adhesion molecule (VCAM-1) expression associated with its cytoplasmic mRNA destabilization and nuclear transcription level. Studies exploring the underlying mechanism of C1INH-mediated suppression in VCAM-1 expression were related to reduction of NF-{kappa}B activation and nuclear translocation in an I{kappa}B{alpha}-dependent manner. The inhibitory effects were associated with reduction of inhibitor I{kappa}B kinase activity and stabilization of the NF-{kappa}B inhibitor I{kappa}B. These findings indicate a novel role for C1INH in inhibition of vascular endothelial activation. These observations could provide the basis for new therapeutic application of C1INH to target inflammatory processes in different pathologic situations.

  2. [Endothelial cell adhesion molecules].

    PubMed

    Ivanov, A N; Norkin, I A; Puchin'ian, D M; Shirokov, V Iu; Zhdanova, O Iu

    2014-01-01

    The review presents current data concerning the functional role of endothelial cell adhesion molecules belonging to different structural families: integrins, selectins, cadherins, and the immunoglobulin super-family. In this manuscript the regulatory mechanisms and factors of adhesion molecules expression and distribution on the surface of endothelial cells are discussed. The data presented reveal the importance of adhesion molecules in the regulation of structural and functional state of endothelial cells in normal conditions and in pathology. Particular attention is paid to the importance of these molecules in the processes of physiological and pathological angiogenesis, regulation of permeability of the endothelial barrier and cell transmigration.

  3. Carboxylated, heteroaryl-substituted chalcones as inhibitors of vascular cell adhesion molecule-1 expression for use in chronic inflammatory diseases.

    PubMed

    Meng, Charles Q; Ni, Liming; Worsencroft, Kimberly J; Ye, Zhihong; Weingarten, M David; Simpson, Jacob E; Skudlarek, Jason W; Marino, Elaine M; Suen, Ki-Ling; Kunsch, Charles; Souder, Amy; Howard, Randy B; Sundell, Cynthia L; Wasserman, Martin A; Sikorski, James A

    2007-03-22

    Starting from a simple chalcone template, structure-activity relationship (SAR) studies led to a series of carboxylated, heteroaryl-substituted chalcone derivatives as novel, potent inhibitors of vascular cell adhesion molecule-1 (VCAM-1) expression. Correlations between lipophilicity determined by calculated logP values and inhibitory efficacy were observed among structurally similar compounds of the series. Various substituents were found to be tolerated at several positions of the chalcone backbone as long as the compounds fell into the right range of lipophilicity. The chalcone alpha,beta-unsaturated ketone moiety seemed to be the pharmacophore required for inhibition of VCAM-1 expression. Compound 19 showed significant antiinflammatory effects in a mouse model of allergic inflammation, indicating that this series of compounds might have therapeutic value for human asthma and other inflammatory disorders. PMID:17323940

  4. Intercellular adhesion molecule-1 in the heart.

    PubMed

    Niessen, Hans W M; Krijnen, Paul A J; Visser, Cees A; Meijer, Chris J L M; Hack, C Erik

    2002-11-01

    Intercellular adhesion molecule-1 (ICAM-1) belongs to the superfamily of immunoglobulin-like adhesion molecules. Up-regulation of ICAM-1 occurs in many different pathophysiological processes. Also, cardiomyocytes can express ICAM-1-for example, in acute myocardial infarction. Moreover, inhibition of ICAM-1 expression in the heart dramatically reduces infarct size. Hence, inhibitors of ICAM-1 may provide a novel therapeutic option for acute myocardial infarction.

  5. Carcinoembryonic antigen-related cell adhesion molecules as surrogate markers for EGFR inhibitor sensitivity in human lung adenocarcinoma

    PubMed Central

    Kobayashi, M; Miki, Y; Ebina, M; Abe, K; Mori, K; Narumi, S; Suzuki, T; Sato, I; Maemondo, M; Endo, C; Inoue, A; Kumamoto, H; Kondo, T; Yamada-Okabe, H; Nukiwa, T; Sasano, H

    2012-01-01

    Background: Lung adenocarcinoma (LADCA) patients with epidermal growth factor receptor (EGFR) mutations are in general associated with relatively high clinical response rate to EGFR-tyrosine kinase inhibitors (TKIs) but not all responded to TKI. It has therefore become important to identify the additional surrogate markers regarding EGFR-TKI sensitivity. Methods: We first examined the effects of EGFR-TKIs, gefitinib and erlotinib, upon cell proliferation of lung adenocarcinoma cell lines. We then evaluated the gene profiles related to EGFR-TKI sensitivity using a microarray analysis. Results of microarray analysis led us to focus on carcinoembryonic antigen-related cell adhesion molecule (CEACAM) family, CEACAM 3, 5, 6, 7, and 19, as potential further surrogate markers of EGFR-TKI sensitivity. We then examined the correlation between the status of CEACAM 3, 5, 6, 7, and 19 immunoreactivity in LADCA and clinicopathological parameters of individual cases. Results: In the cases with EGFR mutations, the status of all CEACAMs examined was significantly higher than that in EGFR wild-type patients, but there were no significant differences in the status of CEACAMs between TKI responder and nonresponder among 22 patients who received gefitinib therapy. However, among 115 EGFR mutation-negative LADCA patients, both CEACAM6 and CEACAM3 were significantly associated with adverse clinical outcome (CEACAM6) and better clinical outcome (CEACAM3). Conclusion: CEACAMs examined in this study could be related to the presence of EGFR mutation in adenocarcinoma cells but not represent the effective surrogate marker of EGFR-TKI in LADCA patients. However, immunohistochemical evaluation of CEACAM3/6 in LADCA patients could provide important information on their clinical outcome. PMID:23099808

  6. Adxanthromycins A and B, new inhibitors of ICAM-1/LFA-1 mediated cell adhesion molecule from Streptomyces sp. NA-148. II. Physico-chemical properties and structure elucidation.

    PubMed

    Takahashi, S; Nakano, T; Koiwa, T; Noshita, T; Funayama, S; Koshino, H; Nakagawa, A

    2000-02-01

    Adxanthromycins A and B are new inhibitors of ICAM-1/LFA-1 mediated cell adhesion molecule isolated from the fermentation broth of Streptomyces sp. NA-148. The molecular formula of adxanthromycins A and B were determined as C42H40O17 and C48H50O22, respectively by FAB-MS and NMR spectral analyses, and the structures of both compounds were elucidated to be a dimeric anthrone peroxide skeleton containing alpha-D-galactose by various NMR spectral analyses and chemical degradation. PMID:10805577

  7. Discovery of novel phenolic antioxidants as inhibitors of vascular cell adhesion molecule-1 expression for use in chronic inflammatory diseases.

    PubMed

    Meng, Charles Q; Somers, Patricia K; Hoong, Lee K; Zheng, X Sharon; Ye, Zhihong; Worsencroft, Kimberly J; Simpson, Jacob E; Hotema, Martha R; Weingarten, M David; MacDOnald, Mathew L; Hill, Russell R; Marino, Elaine M; Suen, Ki-Ling; Luchoomun, Jayraz; Kunsch, Charles; Landers, Laura K; Stefanopoulos, Dimitria; Howard, Randy B; Sundell, Cynthia L; Saxena, Uday; Wasserman, Martin A; Sikorski, James A

    2004-12-01

    Vascular cell adhesion molecule-1 (VCAM-1) mediates recruitment of leukocytes to endothelial cells and is implicated in many inflammatory conditions. Since part of the signal transduction pathway that regulates the activation of VCAM-1 expression is redox-sensitive, compounds with antioxidant properties may have inhibitory effects on VCAM-1 expression. Novel phenolic compounds have been designed and synthesized starting from probucol (1). Many of these compounds demonstrated potent inhibitory effects on cytokine-induced VCAM-1 expression and displayed potent antioxidant effects in vitro. Some of these derivatives (4o, 4p, 4w, and 4x) inhibited lipopolysaccharide (LPS)-induced secretion of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), and IL-6 from human peripheral blood mononuclear cells (hPBMCs) in a concentration-dependent manner in vitro and showed antiinflammatory effects in an animal model. Compounds 4ad and 4ae are currently in clinical trials for the treatment of rheumatoid arthritis (RA) and prevention of chronic organ transplant rejection, respectively. PMID:15566311

  8. Synaptic Cell Adhesion Molecules in Alzheimer's Disease

    PubMed Central

    Leshchyns'ka, Iryna

    2016-01-01

    Alzheimer's disease (AD) is a neurodegenerative brain disorder associated with the loss of synapses between neurons in the brain. Synaptic cell adhesion molecules are cell surface glycoproteins which are expressed at the synaptic plasma membranes of neurons. These proteins play key roles in formation and maintenance of synapses and regulation of synaptic plasticity. Genetic studies and biochemical analysis of the human brain tissue, cerebrospinal fluid, and sera from AD patients indicate that levels and function of synaptic cell adhesion molecules are affected in AD. Synaptic cell adhesion molecules interact with Aβ, a peptide accumulating in AD brains, which affects their expression and synaptic localization. Synaptic cell adhesion molecules also regulate the production of Aβ via interaction with the key enzymes involved in Aβ formation. Aβ-dependent changes in synaptic adhesion affect the function and integrity of synapses suggesting that alterations in synaptic adhesion play key roles in the disruption of neuronal networks in AD. PMID:27242933

  9. Cell-adhesion molecules in memory formation.

    PubMed

    Schmidt, R

    1995-01-23

    After learning events the CNS of higher organisms selects, which acquired informations are permanently stored as a memory trace. This period of memory consolidation is susceptible to interference by biochemical inhibitors of transcription and translation. Ependymin is a specific CNS glycoprotein functionally involved in memory consolidation in goldfish: after active shock-avoidance conditioning ependymin mRNA is rapidly induced in meningeal fibroblasts followed by enhanced synthesis and secretion of several closely related forms of the protein. Intracranial injections of anti-ependymin antisera or antisense oligodeoxynucleotides interfere specifically with memory consolidation, indicating that only de novo synthesized ependymin molecules are involved. Ependymin is capable of directing the growth of central axons in vitro and participates in neuronal regeneration in situ, presumably by its HNK-1 cell-adhesion epitope. Experiments reviewed in this article suggest a model that involves two regulation mechanisms for the function of ependymin in behavioural plasticity: while hormones appear to determine, how much of this cell adhesion molecule is synthesized after learning, local changes of metal cation concentrations in the micro-environment of activated neurons may polymerize ependymin at those synapses, that have to be consolidated to improve their efficacy for future use.

  10. Control of vascular permeability by adhesion molecules

    PubMed Central

    Sarelius, Ingrid H; Glading, Angela J

    2014-01-01

    Vascular permeability is a vital function of the circulatory system that is regulated in large part by the limited flux of solutes, water, and cells through the endothelial cell layer. One major pathway through this barrier is via the inter-endothelial junction, which is driven by the regulation of cadherin-based adhesions. The endothelium also forms attachments with surrounding proteins and cells via 2 classes of adhesion molecules, the integrins and IgCAMs. Integrins and IgCAMs propagate activation of multiple downstream signals that potentially impact cadherin adhesion. Here we discuss the known contributions of integrin and IgCAM signaling to the regulation of cadherin adhesion stability, endothelial barrier function, and vascular permeability. Emphasis is placed on known and prospective crosstalk signaling mechanisms between integrins, the IgCAMs- ICAM-1 and PECAM-1, and inter-endothelial cadherin adhesions, as potential strategic signaling nodes for multipartite regulation of cadherin adhesion. PMID:25838987

  11. Control of vascular permeability by adhesion molecules.

    PubMed

    Sarelius, Ingrid H; Glading, Angela J

    2015-01-01

    Vascular permeability is a vital function of the circulatory system that is regulated in large part by the limited flux of solutes, water, and cells through the endothelial cell layer. One major pathway through this barrier is via the inter-endothelial junction, which is driven by the regulation of cadherin-based adhesions. The endothelium also forms attachments with surrounding proteins and cells via 2 classes of adhesion molecules, the integrins and IgCAMs. Integrins and IgCAMs propagate activation of multiple downstream signals that potentially impact cadherin adhesion. Here we discuss the known contributions of integrin and IgCAM signaling to the regulation of cadherin adhesion stability, endothelial barrier function, and vascular permeability. Emphasis is placed on known and prospective crosstalk signaling mechanisms between integrins, the IgCAMs- ICAM-1 and PECAM-1, and inter-endothelial cadherin adhesions, as potential strategic signaling nodes for multipartite regulation of cadherin adhesion. PMID:25838987

  12. Single-molecule mechanics of mussel adhesion

    NASA Astrophysics Data System (ADS)

    Lee, Haeshin; Scherer, Norbert F.; Messersmith, Phillip B.

    2006-08-01

    The glue proteins secreted by marine mussels bind strongly to virtually all inorganic and organic surfaces in aqueous environments in which most adhesives function poorly. Studies of these functionally unique proteins have revealed the presence of the unusual amino acid 3,4-dihydroxy-L-phenylalanine (dopa), which is formed by posttranslational modification of tyrosine. However, the detailed binding mechanisms of dopa remain unknown, and the chemical basis for mussels' ability to adhere to both inorganic and organic surfaces has never been fully explained. Herein, we report a single-molecule study of the substrate and oxidation-dependent adhesive properties of dopa. Atomic force microscopy (AFM) measurements of a single dopa residue contacting a wet metal oxide surface reveal a surprisingly high strength yet fully reversible, noncovalent interaction. The magnitude of the bond dissociation energy as well as the inability to observe this interaction with tyrosine suggests that dopa is critical to adhesion and that the binding mechanism is not hydrogen bond formation. Oxidation of dopa, as occurs during curing of the secreted mussel glue, dramatically reduces the strength of the interaction to metal oxide but results in high strength irreversible covalent bond formation to an organic surface. A new picture of the interfacial adhesive role of dopa emerges from these studies, in which dopa exploits a remarkable combination of high strength and chemical multifunctionality to accomplish adhesion to substrates of widely varying composition from organic to metallic. 3,4-dihydroxylphenylalanine | atomic force microscopy | mussel adhesive protein

  13. Intercellular adhesion molecule 1 is the major adhesion molecule expressed during schistosome granuloma formation.

    PubMed Central

    Ritter, D M; McKerrow, J H

    1996-01-01

    Endothelial cell adhesion molecules play a key role in inflammation by initiating leukocyte trafficking. One of the most complex inflammatory responses is the formation of a cellular granuloma. Expression of adhesion molecules during granuloma formation was investigated by using the murine host reaction to schistosome parasite eggs deposited in the liver as a model. By both immunohistochemistry and lymphocyte adhesion assays, the predominant interaction identified was between intercellular adhesion molecule 1 (ICAM-1) and its cognate integrin, leukocyte functional antigen 1 (LFA-1). ICAM-1 expression on sinusoidal endothelium was induced when eggs were first deposited in the liver, peaked in parallel with granuloma size, and was downregulated with modulation of the granuloma. Polyacrylamide beads coated with soluble parasite egg antigens could induce ICAM-1 expression on endothelial cells in vitro only in the presence of tumor necrosis factor alpha, a cytokine previously shown to be key to granuloma formation. A role for ICAM-1 in recruiting lymphocytes to the hepatic granuloma was also supported by the observation that lymphocytes preincubated with anti-LFA-1 antibody did not bind to granulomas in tissue sections. While ICAM-1 is the predominant adhesion molecule in schistosome egg granuloma formation in wild-type mice, when the ICAM-1 gene is knocked out, vascular cell adhesion molecule 1 is upregulated and granuloma formation is preserved. PMID:8890229

  14. Small-molecule caspase inhibitors

    NASA Astrophysics Data System (ADS)

    Zhenodarova, S. M.

    2010-02-01

    The review considers low-molecular weight inhibitors of caspases, cysteine proteases being key contributors to apoptosis (programmed cell death). The inhibitors with aspartic acid residues or various heterocyclic systems (both synthetic and natural) are covered. Their possible mechanisms of action are discussed. Data on inhibitor structure-activity relationship studies are systematically surveyed. The interactions of the non-peptide fragments of an inhibitor with the enzymes are examined. Examples of the use of some inhibitors for apoptosis suppression are provided.

  15. [Effect of erythromycin on neutrophil adhesion molecules].

    PubMed

    Kusano, S; Mukae, H; Morikawa, T; Asai, T; Sawa, H; Morikawa, N; Oda, H; Sakito, O; Shukuwa, C; Senju, R

    1993-01-01

    The mechanisms of erythromycin (EM) in chronic lower respiratory tract diseases including diffuse panbronchiolitis (DPB) has been reported. In this study we investigated the effect of EM on peripheral neutrophil adhesion molecules such as LFA-1 and Mac-1 obtained from six healthy subjects. Pretreatment of neutrophils with each concentration (10 ng/ml approximately 100 micrograms/ml) of EM resulted in no significant reduction in the expression of LFA-1 alpha, beta and Mac-1. Moreover, EM had no capability of reducing these expressions even when neutrophils were pretreated with 1 microgram/ml of EM at time from 0 to 60 min. These findings indicate that EM does not directly reduce the expression of LFA-1 alpha, beta and Mac-1 on peripheral neutrophil obtained from healthy subjects. PMID:8450276

  16. Circulating adhesion molecules in obstructive sleep apnea and cardiovascular disease.

    PubMed

    Pak, Victoria M; Grandner, Michael A; Pack, Allan I

    2014-02-01

    Over 20 years of evidence indicates a strong association between obstructive sleep apnea (OSA) and cardiovascular disease. Although inflammatory processes have been heavily implicated as an important link between the two, the mechanism for this has not been conclusively established. Atherosclerosis may be one of the mechanisms linking OSA to cardiovascular morbidity. This review addresses the role of circulating adhesion molecules in patients with OSA, and how these may be part of the link between cardiovascular disease and OSA. There is evidence for the role of adhesion molecules in cardiovascular disease risk. Some studies, albeit with small sample sizes, also show higher levels of adhesion molecules in patients with OSA compared to controls. There are also studies that show that levels of adhesion molecules diminish with continuous positive airway pressure therapy. Limitations of these studies include small sample sizes, cross-sectional sampling, and inconsistent control for confounding variables known to influence adhesion molecule levels. There are potential novel therapies to reduce circulating adhesion molecules in patients with OSA to diminish cardiovascular disease. Understanding the role of cell adhesion molecules generated in OSA will help elucidate one mechanistic link to cardiovascular disease in patients with OSA.

  17. Cell adhesion molecules and in vitro fertilization.

    PubMed

    Simopoulou, Maria; Nikolopoulou, Elena; Dimakakos, Andreas; Charalabopoulos, Konstantinos; Koutsilieris, Michael

    2014-01-01

    This review addresses issues regarding the need in the in vitro fertilization (IVF) field for further predictive markers enhancing the standing embryo selection criteria. It aims to serve as a source of defining information for an audience interested in factors related to the wide range of multiple roles played by cell adhesion molecules (CAMs) in several aspects of IVF ultimately associated with the success of an IVF cycle. We begin by stressing the importance of enriching the standing embryo selection criteria available aiming for the golden standard: "extract as much information as possible focusing on non-invasive techniques" so as to guide us towards selecting the embryo with the highest implantation potential. We briefly describe the latest trends on how to best select the right embryo, moving closer towards elective single embryo transfer. These trends are: frozen embryo transfer for all, preimplantation genetic screening, non-invasive selection criteria, and time-lapse imaging. The main part of this review is dedicated to categorizing and presenting published research studies focused on the involvement of CAMs in IVF and its final outcome. Specifically, we discuss the association of CAMs with conditions and complications that arise from performing assisted reproductive techniques, such as ovarian hyperstimulation syndrome, the state of the endometrium, and tubal pregnancies, as well as the levels of CAMs in biological materials available in the IVF laboratory such as follicular fluid, trophectoderm, ovarian granulosa cells, oocytes, and embryos. To conclude, since CAMs have been successfully employed as a diagnostic tool in several pathologies in routine clinical work, we suggest that their multi-faceted nature could serve as a prognostic marker in assisted reproduction, aiming to enrich the list of non-invasive selection and predictive criteria in the IVF setting. We propose that in light of the well-documented involvement of CAMs in the developmental

  18. CCN4 induces vascular cell adhesion molecule-1 expression in human synovial fibroblasts and promotes monocyte adhesion.

    PubMed

    Liu, Ju-Fang; Hou, Sheng-Mou; Tsai, Chun-Hao; Huang, Chun-Yin; Hsu, Chin-Jung; Tang, Chih-Hsin

    2013-05-01

    CCN4 is a cysteine-rich protein that belongs to the Cyr61, CTGF, Nov family of matricellular proteins. Here, we investigated the intracellular signaling pathways involved in CCN4-induced vascular cell adhesion molecule-1 expression in human osteoarthritis synovial fibroblasts. Stimulation of OASFs with CCN4 induced VCAM-1 expression. CCN4-induced VCAM-1 expression was attenuated by αvβ5 or α6β1 integrin antibody, Syk inhibitor, PKCδ inhibitor (rottlerin), JNK inhibitor (SP600125), and AP-1 inhibitors (curcumin and tanshinone). Stimulation of cells with CCN4 increased Syk, PKCδ, and JNK activation. Treatment of OASFs with CCN4 also increased c-Jun phosphorylation, AP-1-luciferase activity, and c-Jun binding to the AP-1 element in the VCAM-1 promoter. Moreover, up-regulation of VCAM-1 increased the adhesion of monocytes to OASF monolayers, and this adhesion was attenuated by transfection with a VCAM-1 siRNA. Our results suggest that CCN4 increases VCAM-1 expression in human OASFs via the Syk, PKCδ, JNK, c-Jun, and AP-1 signaling pathways. The CCN4-induced VCAM-1 expression promoted monocyte adhesion to human OASFs. PMID:23313051

  19. Small molecules inhibitors of plasminogen activator inhibitor-1 - an overview.

    PubMed

    Rouch, Anne; Vanucci-Bacqué, Corinne; Bedos-Belval, Florence; Baltas, Michel

    2015-03-01

    PAI-1, a glycoprotein from the serpin family and the main inhibitor of tPA and uPA, plays an essential role in the regulation of intra and extravascular fibrinolysis by inhibiting the formation of plasmin from plasminogen. PAI-1 is also involved in pathological processes such as thromboembolic diseases, atherosclerosis, fibrosis and cancer. The inhibition of PAI-1 activity by small organic molecules has been observed in vitro and with some in vivo models. Based on these findings, PAI-1 appears as a potential therapeutic target for several pathological conditions. Over the past decades, many efforts have therefore been devoted to developing PAI-1 inhibitors. This article provides an overview of the publishing activity on small organic molecules used as PAI-1 inhibitors. The chemical synthesis of the most potent inhibitors as well as their biological and biochemical evaluations is also presented.

  20. Small-molecule inhibitors of myosin proteins

    PubMed Central

    Bond, Lisa M; Tumbarello, David A; Kendrick-Jones, John; Buss, Folma

    2014-01-01

    Advances in screening and computational methods have enhanced recent efforts to discover/design small-molecule protein inhibitors. One attractive target for inhibition is the myosin family of motor proteins. Myosins function in a wide variety of cellular processes, from intracellular trafficking to cell motility, and are implicated in several human diseases (e.g., cancer, hypertrophic cardiomyopathy, deafness and many neurological disorders). Potent and selective myosin inhibitors are, therefore, not only a tool for understanding myosin function, but are also a resource for developing treatments for diseases involving myosin dysfunction or overactivity. This review will provide a brief overview of the characteristics and scientific/therapeutic applications of the presently identified small-molecule myosin inhibitors before discussing the future of myosin inhibitor and activator design. PMID:23256812

  1. Cell adhesion molecules and in vitro fertilization.

    PubMed

    Simopoulou, Maria; Nikolopoulou, Elena; Dimakakos, Andreas; Charalabopoulos, Konstantinos; Koutsilieris, Michael

    2014-01-01

    This review addresses issues regarding the need in the in vitro fertilization (IVF) field for further predictive markers enhancing the standing embryo selection criteria. It aims to serve as a source of defining information for an audience interested in factors related to the wide range of multiple roles played by cell adhesion molecules (CAMs) in several aspects of IVF ultimately associated with the success of an IVF cycle. We begin by stressing the importance of enriching the standing embryo selection criteria available aiming for the golden standard: "extract as much information as possible focusing on non-invasive techniques" so as to guide us towards selecting the embryo with the highest implantation potential. We briefly describe the latest trends on how to best select the right embryo, moving closer towards elective single embryo transfer. These trends are: frozen embryo transfer for all, preimplantation genetic screening, non-invasive selection criteria, and time-lapse imaging. The main part of this review is dedicated to categorizing and presenting published research studies focused on the involvement of CAMs in IVF and its final outcome. Specifically, we discuss the association of CAMs with conditions and complications that arise from performing assisted reproductive techniques, such as ovarian hyperstimulation syndrome, the state of the endometrium, and tubal pregnancies, as well as the levels of CAMs in biological materials available in the IVF laboratory such as follicular fluid, trophectoderm, ovarian granulosa cells, oocytes, and embryos. To conclude, since CAMs have been successfully employed as a diagnostic tool in several pathologies in routine clinical work, we suggest that their multi-faceted nature could serve as a prognostic marker in assisted reproduction, aiming to enrich the list of non-invasive selection and predictive criteria in the IVF setting. We propose that in light of the well-documented involvement of CAMs in the developmental

  2. Expression sequences of cell adhesion molecules.

    PubMed Central

    Crossin, K L; Chuong, C M; Edelman, G M

    1985-01-01

    A reexamination of the expression of cell adhesion molecules (CAMs) during the development of the chicken embryo was carried out using more sensitive immunocytochemical techniques than had been used previously. While the previously determined sequence of CAM expression was confirmed, neural CAM (N-CAM) was also detected on endodermal structures such as the lung epithelium, gut epithelium, and pancreas and on budding structures such as the pancreatic duct and gall bladder. It was also found on ectodermal derivatives of the skin. In most of these sites, N-CAM expression was transient, but in the chicken embryo lung, the epithelium remained positive for N-CAM and liver CAM (L-CAM) into adult life. Thus, at one time or another, both of these primary CAMs can be expressed on derivatives of all three germ layers. At sites of embryonic induction, epithelial cells expressing both L-CAM and N-CAM, or L-CAM only, were apposed to mesenchymal cells expressing N-CAM. Examples included epiblast (NL) and notochord (N); endodermal epithelium (NL) and lung mesenchyme (N); Wolffian duct (NL) and mesonephric mesenchyme (N); apical ectodermal ridge (NL) and limb mesenchyme (N); and feather placode (L) and dermal condensation (N). The cumulative observations indicate that cell surface modulation of the primary CAMs at induction sites can be classified into two modes. In mode I, expression of N-CAM (or both CAMs) in mesenchyme decreases to low amounts at the cell surface, and then N-CAM is reexpressed. In mode II, one or the other CAM disappears from epithelia expressing both CAMs. As a result of the primary processes of development, collectives of cells linked by N-CAM and undergoing modulation mode I are brought into the proximity of collectives of cells linked by L-CAM plus N-CAM or by L-CAM undergoing modulation mode II. Such adjoining cell collectives or CAM couples were found at all sites of embryonic induction examined. Images PMID:3863135

  3. Cell adhesion molecules: detection with univalent second antibody

    PubMed Central

    1980-01-01

    Identification of cell surface molecules that play a role in cell-cell adhesion (here called cell adhesion molecules) has been achieved by demonstrating the inhibitory effect of univalent antibodies that bind these molecules in an in vitro assay of cell-cell adhesion. A more convenient reagent, intact (divalent) antibody, has been avoided because it might agglutinate the cells rather than blocking cell-cell adhesion. In this report, we show that intact rabbit immunoglobulin directed against certain cell surface molecules of Dictyostelium discoideum blocks cell-cell adhesion when the in vitro assay is performed in the presence of univalent goat anti-rabbit antibody. Under appropriate experimental conditions, the univalent second antibody blocks agglutination induced by the rabbit antibody without significantly interfering with its effect on cell-cell adhesion. This method promises to be useful for screening monoclonal antibodies raised against potential cell adhesion molecules because: (a) it allows for the screening of large numbers of antibody samples without preparation of univalent fragments; and (b) it requires much less antibody because of the greater affinity of divalent antibodies for antigens. PMID:6970200

  4. A hot water extract of Curcuma longa inhibits adhesion molecule protein expression and monocyte adhesion to TNF-α-stimulated human endothelial cells.

    PubMed

    Kawasaki, Kengo; Muroyama, Koutarou; Yamamoto, Norio; Murosaki, Shinji

    2015-01-01

    The recruitment of arterial leukocytes to endothelial cells is an important step in the progression of various inflammatory diseases. Therefore, its modulation is thought to be a prospective target for the prevention or treatment of such diseases. Adhesion molecules on endothelial cells are induced by proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), and contribute to the recruitment of leukocytes. In the present study, we investigated the effect of hot water extract of Curcuma longa (WEC) on the protein expression of adhesion molecules, monocyte adhesion induced by TNF-α in human umbilical vascular endothelial cells (HUVECs). Treatment of HUVECs with WEC significantly suppressed both TNF-α-induced protein expression of adhesion molecules and monocyte adhesion. WEC also suppressed phosphorylation and degradation of nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) induced by TNF-α in HUVECs, suggesting that WEC inhibits the NF-κB signaling pathway.

  5. Small-Molecule Inhibitors of Urea Transporters

    PubMed Central

    Verkman, Alan S.; Esteva-Font, Cristina; Cil, Onur; Anderson, Marc O.; Li, Fei; Li, Min; Lei, Tianluo; Ren, Huiwen; Yang, Baoxue

    2015-01-01

    Urea transporter (UT) proteins, which include isoforms of UT-A in kidney tubule epithelia and UT-B in vasa recta endothelia and erythrocytes, facilitate urinary concentrating function. Inhibitors of urea transporter function have potential clinical applications as sodium-sparing diuretics, or ‘urearetics,’ in edema from different etiologies, such as congestive heart failure and cirrhosis, as well as in syndrome of inappropriate antidiuretic hormone (SIADH). High-throughput screening of drug-like small molecules has identified UT-A and UT-B inhibitors with nanomolar potency. Inhibitors have been identified with different UT-A versus UT-B selectivity profiles and putative binding sites on UT proteins. Studies in rodent models support the utility of UT inhibitors in reducing urinary concentration, though testing in clinically relevant animal models of edema has not yet been done. PMID:25298345

  6. Cell Adhesion Molecules and Ubiquitination—Functions and Significance

    PubMed Central

    Homrich, Mirka; Gotthard, Ingo; Wobst, Hilke; Diestel, Simone

    2015-01-01

    Cell adhesion molecules of the immunoglobulin (Ig) superfamily represent the biggest group of cell adhesion molecules. They have been analyzed since approximately 40 years ago and most of them have been shown to play a role in tumor progression and in the nervous system. All members of the Ig superfamily are intensively posttranslationally modified. However, many aspects of their cellular functions are not yet known. Since a few years ago it is known that some of the Ig superfamily members are modified by ubiquitin. Ubiquitination has classically been described as a proteasomal degradation signal but during the last years it became obvious that it can regulate many other processes including internalization of cell surface molecules and lysosomal sorting. The purpose of this review is to summarize the current knowledge about the ubiquitination of cell adhesion molecules of the Ig superfamily and to discuss its potential physiological roles in tumorigenesis and in the nervous system. PMID:26703751

  7. Adhesion Molecules: Master Controllers of the Circulatory System.

    PubMed

    Schmidt, Eric P; Kuebler, Wolfgang M; Lee, Warren L; Downey, Gregory P

    2016-03-15

    This manuscript will review our current understanding of cellular adhesion molecules (CAMs) relevant to the circulatory system, their physiological role in control of vascular homeostasis, innate and adaptive immune responses, and their importance in pathophysiological (disease) processes such as acute lung injury, atherosclerosis, and pulmonary hypertension. This is a complex and rapidly changing area of research that is incompletely understood. By design, we will begin with a brief overview of the structure and classification of the major groups of adhesion molecules and their physiological functions including cellular adhesion and signaling. The role of specific CAMs in the process of platelet aggregation and hemostasis and leukocyte adhesion and transendothelial migration will be reviewed as examples of the complex and cooperative interplay between CAMs during physiological and pathophysiological processes. The role of the endothelial glycocalyx and the glycobiology of this complex system related to inflammatory states such as sepsis will be reviewed. We will then focus on the role of adhesion molecules in the pathogenesis of specific disease processes involving the lungs and cardiovascular system. The potential of targeting adhesion molecules in the treatment of immune and inflammatory diseases will be highlighted in the relevant sections throughout the manuscript.

  8. Expression and cell distribution of the intercellular adhesion molecule, vascular cell adhesion molecule, endothelial leukocyte adhesion molecule, and endothelial cell adhesion molecule (CD31) in reactive human lymph nodes and in Hodgkin's disease.

    PubMed Central

    Ruco, L. P.; Pomponi, D.; Pigott, R.; Gearing, A. J.; Baiocchini, A.; Baroni, C. D.

    1992-01-01

    The immunocytochemical expression of intercellular adhesion molecule (ICAM-1), vascular cell adhesion molecule (VCAM-1), endothelial leukocyte adhesion molecule (ELAM-1), endothelial cell adhesion molecule (EndoCAM CD31), and HLA-DR antigens was investigated in sections of 24 reactive lymph nodes and in 15 cases of Hodgkin's disease. ICAM-1 was detected in sinus macrophages, follicular dendritic reticulum cells (FDRCs), interdigitating reticulum cells (IDRCs), epithelioid macrophages, Hodgkin's cells (HCs), and vascular endothelium. ICAM-1 expression was often associated with that of HLA-DR antigens. VCAM-1 was detected in FDRCs, in fibroblast reticulum cells (FRCs), in macrophages, and in rare blood vessels. EndoCAM (CD31) was constitutively expressed in all types of endothelial cells, sinus macrophages, and in epithelioid granulomas. ELAM-1 was selectively expressed by activated endothelial cells of high endothelium venules (HEVs). When expression of the inducible adhesion molecules ICAM-1, VCAM-1 and ELAM-1 was comparatively evaluated in HEVs, it was found that ICAM-1 + HEVs were present in all reactive and HD nodes, whereas ELAM-1 and/or VCAM-1 were expressed only in those pathologic conditions characterized by high levels of interleukin-1/tumor necrosis factor (IL-1/TNF) production, such as granulomatosis and Hodgkin's disease. In Hodgkin's disease, the expression of ELAM-1/VCAM-1 was more pronounced in cases of nodular sclerosis and was associated with a significantly higher content of perivascular neutrophils. Images Figure 1 Figure 2 PMID:1605306

  9. Proteolysis of cell adhesion molecules by serine proteases: a role in long term potentiation?

    PubMed

    Hoffman, K B; Martinez, J; Lynch, G

    1998-11-16

    Tissue plasminogen activator (tPA), a serine protease endogenous to hippocampal neurons, is shown to recognize a highly conserved sequence in the extracellular domain of cell adhesion molecules (CAMs). When added to brain homogenates, tPA generated a CAM fragment similar in size to that produced in hippocampal slices by brief periods of NMDA receptor stimulation. The serine protease inhibitor 4-(2-Aminoethyl)-benzenesulfonyl fluoride blocked the effects of tPA with an approximately 50% suppression at 250 microM. The inhibitor at this concentration had no evident effect on synaptic responses but caused long term potentiation to decay back to baseline over a 1 h period. These results suggest that extracellular breakdown of cell adhesion molecules initiated by NMDA receptors and mediated by serine proteases contributes to the formation of stable potentiation.

  10. Specific biomembrane adhesion -Indirect lateral interactions between bound receptor molecules

    NASA Astrophysics Data System (ADS)

    Maier, C. W.; Behrisch, A.; Kloboucek, A.; Simson, D. A.; Merkel, R.

    We studied biomembrane adhesion using the micropipet aspiration technique. Adhesion was caused by contact site A, a laterally mobile and highly specific cell adhesion molecule from Dictyostelium discoideum, reconstituted in lipid vesicles of DOPC (L-α-dioleoylphosphatidylcholine) with an addition of 5 mol % DOPE-PEG{2000} (1,2-diacyl-sn-glycero-3-phosphatidylethanolamine-N-[poly(ethyleneglycol) 2000]). The "fuzzy" membrane mimics the cellular plasma membrane including the glycocalyx. We found adhesion and subsequent receptor migration into the contact zone. Using membrane tension jumps to probe the equation of state of the two-dimensional "gas" of bound receptor pairs within the contact zone, we found strong, attractive lateral interactions.

  11. Matrine inhibits the expression of adhesion molecules in activated vascular smooth muscle cells.

    PubMed

    Liu, Jun; Zhang, Lihua; Ren, Yingang; Gao, Yanli; Kang, Li; Lu, Shaoping

    2016-03-01

    Atherosclerosis is a chronic inflammatory disease associated with increased expression of adhesion molecules in vascular smooth muscle cells (VSMCs). Matrine is a main active ingredient of Sophora flavescens roots, which are used to treat inflammatory diseases. However, the effects of matrine on the expression of adhesion molecules in VSMCs have largely remained elusive. Therefore, the present study investigated the effects of matrine on the expression of adhesion molecules in tumor necrosis factor (TNF)‑α‑stimulated human aortic smooth muscle cells (HASMCs). The results showed that matrine inhibited the expression of vascular cell adhesion molecule‑1 (VCAM‑1) and intercellular adhesion molecule‑1 (ICAM‑1) in TNF‑α‑stimulated HASMCs. Matrine markedly inhibited the TNF‑α‑induced expression of nuclear factor (NF)‑κB p65 and prevented the TNF‑α‑caused degradation of inhibitor of NF‑κB; it also inhibited TNF‑α‑induced activation of mitogen‑activated protein kinases (MAPKs). Furthermore, matrine inhibited the production of intracellular reactive oxygen species (ROS) in TNF‑α‑stimulated HASMCs. In conclusion, the results of the present study demonstrated that matrine inhibited the expression of VCAM‑1 and ICAM‑1 in TNF‑α‑stimulated HASMCs via the suppression of ROS production as well as NF‑κB and MAPK pathway activation. Therefore, matrine may have a potential therapeutic use for preventing the advancement of atherosclerotic lesions.

  12. Small Molecule Inhibitor of AICAR Transformylase Homodimerization

    PubMed Central

    Spurr, Ian B.; Birts, Charles N.; Cuda, Francesco; Benkovic, Stephen J; Blaydes, Jeremy P.; Tavassoli, Ali

    2012-01-01

    Aminoimidazole carboxamide ribonucleotide transformylase/inosine monophosphate cyclohydrolase (ATIC) is a bifunctional homodimeric enzyme that catalyses the last two steps of de novo purine biosynthesis. Homodimerization of ATIC, a protein-protein interaction with an interface of over 5000 Å2, is required for its aminoimidazole carboxamide ribonucleotide (AICAR) transformylase activity, with the active sites forming at the interface of the interacting proteins. Here, we report the development of a small-molecule inhibitor of AICAR transformylase that functions by preventing the homodimerization of ATIC. The compound is derived from a previously reported cyclic hexa-peptide inhibitor of AICAR transformylase (with a Ki of 17 μM), identified by high-throughput screening. The active motif of the cyclic peptide is identified as an arginine-tyrosine dipeptide, a capped analogue of which inhibits AICAR transformylase with a Ki of 84 μM. A library of non-natural analogues of this dipeptide was designed, synthesized, and assayed. The most potent compound inhibits AICAR transformylase with a Ki of 685 nM, a 25-fold improvement in activity from the parent cyclic peptide. The potential for this AICAR transformylase inhibitor in cancer therapy is assessed by studying its effect on the proliferation of a model breast cancer cell line. Using a non-radioactive proliferation assay and live cell imaging, a dose-dependent reduction in cell numbers and cell division rates was observed in cells treated with our ATIC dimerization inhibitor. PMID:22764122

  13. Interleukin-12-induced adhesion molecule expression in murine liver.

    PubMed Central

    Myers, K. J.; Eppihimer, M. J.; Hall, L.; Wolitzky, B.

    1998-01-01

    Systemically administered interleukin (IL)-12 causes liver inflammation in mice characterized by Kupffer cell proliferation and hypertrophy, hepatocyte necrosis, and multifocal accumulations of leukocytes in the hepatic parenchyma and around portal tracts and central veins. We have used both immunohistochemical staining and radiolabeled antibody quantitation to examine adhesion molecule expression in the livers of mice dosed daily with murine IL-12. Cells infiltrating livers of IL-12-treated mice were primarily mononuclear leukocytes expressing LFA-1, VLA-4, MAC-1, and CD18 adhesion molecules but little L-selectin. Kupffer cells constitutively expressed LFA-1 and smaller amounts of MAC-1, and high levels of ICAM-1 were constitutively expressed by liver sinusoidal lining cells, portal tract, and central vein endothelia. With IL-12 treatment, existing ICAM-1 expression was up-regulated and de novo expression occurred along bile duct epithelia. VCAM-1 levels were dramatically increased, with induced expression occurring along portal tract and central vein endothelia and scattered bile duct epithelial cells and in aggregations of cells in perivascular areas and the liver parenchyma. Although constitutive expression of E- and P-selectin was negligible, Il-12 induced a moderate rise in E-selectin levels. These increases in adhesion molecule expression may have implications for the therapeutic use of IL-12, especially in patients with liver disease or autoimmune conditions where augmented adhesion molecule expression may be critical to disease pathogenesis. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:9466572

  14. Effect of Linomide on adhesion molecules, TNF-alpha, nitrogen oxide, and cell adhesion.

    PubMed

    Abdul-Hai, A; Hershkoviz, R; Weiss, L; Lider, O; Slavin, S

    2005-02-01

    Linomide (quinoline-3-carboxamide) is an immunomodulator with anti-inflammatory effects in rodents with autoimmune diseases. Its mode of action still remains to be elucidated. We hypothesized that an investigation of T cell interactions with the extracellular matrix (ECM), composed of glycoproteins such as fibronectin (FN) and laminin (LN), might provide better understanding of their in vivo mode of action in extravascular inflammatory sites. We examined the effect of Linomide on T cell adhesion to intact ECM, and separately to LN, and FN, and on the release and production of tumor necrosis factor (TNFalpha) and nitrogen oxide (NO) in relation to adhesive molecules in non-obese diabetic (NOD) female spleen cells, focusing on intracellular adhesion molecule-1 (ICAM-1) and CD44. NOD female mice that developed spontaneous autoimmune insulitis, which destroys pancreatic islets and subsequently leads to insulin-deficient diabetes mellitus, were studied. Linomide, given in the drinking water or added to tissue cultures in vitro, inhibited the beta1 integrin-mediated adhesion of T cells to ECM, FN and LN, as well as the production and release of TNFalpha and NO, which play a major role in the induction and propagation of T cell-mediated insulitis. In addition, exposure of T cells to Linomide resulted in increased expression of CD44 and ICAM-1 molecules on spleen cells of Linomide-treated mice; such an increase in adhesion molecule expression may lead to more effective arrest of T cell migration in vivo. The regulation of T-cell adhesion, adhesion receptor expression, and inhibition of TNFalpha and NO secretion by Linomide may explain its beneficial role and provide a new tool for suppressing self-reactive T cell-dependent autoimmune diseases. PMID:15652754

  15. Evaluation of soluble cell adhesion molecules in atopic dermatitis.

    PubMed

    Koide, M; Furukawa, F; Tokura, Y; Shirahama, S; Takigawa, M

    1997-02-01

    Recent studies have indicated the importance of cell adhesion molecules (CAMs) between the vascular endothelium and activated leukocytes in various inflammatory skin diseases. Soluble forms of CAMs (sCAMs) have also been detected in sera from such diseases. In order to elucidate the role of the soluble forms in skin inflammation, we determined the serum levels of E-selectin, vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) in patients with atopic dermatitis (AD). Using an enzyme-linked immunosorbent assay, we quantified sCAMs levels in 21 patients with atopic dermatitis and in 16 healthy controls. In severe AD patients, levels of these three types of sCAMs were markedly elevated. sE-selectin was significantly elevated in severe AD over the levels in mild AD. A positive correlation with individual clinical activity was found for changes in the sE-selectin and sVCAM-1 levels. sE-selectin levels were correlated with the serum IgE levels and the number of eosinophils. The sVCAM-1 level was also significantly correlated with the number of monocytes. Among these three molecules, sE-selectin appeared to be the most sensitive clinical parameter in monitoring the clinical course of AD patients.

  16. Higher-order architecture of cell adhesion mediated by polymorphic synaptic adhesion molecules neurexin and neuroligin.

    PubMed

    Tanaka, Hiroki; Miyazaki, Naoyuki; Matoba, Kyoko; Nogi, Terukazu; Iwasaki, Kenji; Takagi, Junichi

    2012-07-26

    Polymorphic adhesion molecules neurexin and neuroligin (NL) mediate asymmetric trans-synaptic adhesion, which is crucial for synapse development and function. It is not known whether or how individual synapse function is controlled by the interactions between variants and isoforms of these molecules with differing ectodomain regions. At a physiological concentration of Ca(2+), the ectodomain complex of neurexin-1 β isoform (Nrx1β) and NL1 spontaneously assembled into crystals of a lateral sheet-like superstructure topologically compatible with transcellular adhesion. Correlative light-electron microscopy confirmed extracellular sheet formation at the junctions between Nrx1β- and NL1-expressing non-neuronal cells, mimicking the close, parallel synaptic membrane apposition. The same NL1-expressing cells, however, did not form this higher-order architecture with cells expressing the much longer neurexin-1 α isoform, suggesting a functional discrimination mechanism between synaptic contacts made by different isoforms of neurexin variants.

  17. Differential adhesiveness between blood and marrow leukemic cells having similar pattern of VLA adhesion molecule expression.

    PubMed

    Thomas, X; Anglaret, B; Bailly, M; Maritaz, O; Magaud, J P; Archimbaud, E

    1998-10-01

    Functional adhesion of blood and marrow leukemic cells from 14 acute myeloid leukemia patients presenting with hyperleukocytosis was evaluated by performing cytoadhesion assays on purified (extracellular matrix proteins) and non-purified supports (MRC5 fibroblastic cell line). Results, in 30-min chromium release assay, show a mean +/- S.D. adhesion to fibronectin, collagen, and laminin respectively of 30 +/- 17%, 20 +/- 13%, 25 +/- 17% for blood leukemic cells and 18 +/- 11%, 11 +/- 10%, 11 +/- 8% for marrow leukemic cells. These differences between blood and marrow cells were statistically significant (respectively P = 0.005, P = 0.01 and P = 0.002), while no difference was noted regarding adhesion to non-purified supports. The higher adhesion of blood blast cells to purified supports was observed regardless of CD34 expression. No significant difference was observed in the expression of cell surface VLA-molecules (CD29, CD49b, CD49d, CD49e, CD49f) between blood and marrow blast cells. The addition of GM-CSF or G-CSF induced increased adhesion of marrow blasts and decreased adhesion of blood blasts leading to a loss of the difference between blood and marrow cells. In a 60-min chromium release assay, marrow blasts adhered even more than blood leukemic cells to fibronectin. In contrast, marrow blasts from 'aleukemic' acute myeloid leukemia patients did not show any modification regarding their adhesion to extracellular matrix proteins when co-cultured with growth factors. PMID:9766756

  18. PEPTIDE INHIBITORS OF MK2 SHOW PROMISE FOR INHIBITION OF ABDOMINAL ADHESIONS

    PubMed Central

    Ward, Brian C.; Kavalukas, Sandra; Brugnano, Jamie; Barbul, Adrian; Panitch, Alyssa

    2011-01-01

    Background Abdominal adhesions are a common side effect of surgical procedures with complications including infertility, chronic pain, and bowel obstruction, which may lead to the need for surgical lyses of the adhesions. Mitogen-activated protein kinase-activated protein kinase 2 (MK2) has been implicated in several diseases involving inflammation and fibrosis. Thus, the development of a cell-penetrating peptide (CPP) that modulates MK2 activity may confer therapeutic benefit after abdominal surgery in general and more specifically after bowel anastomosis. Study Design This study evaluated the function of a CPP inhibitor of MK2 in human mesothelial cells and in a rat bowel anastomosis model. To determine IC50 and basic specificity, kinase inhibition was performed using a radiometric assay. Enzyme-Linked Immunoassay (ELISA) was used to evaluate interleukin-6 (IL-6) expression in response to IL-1β and tumor necrosis factor-α (TNF-α) stimulation in vitro to validate MK2 kinase inhibition. Following bowel anastomosis (10 rats for each control and treatment at 4 and 10 days), the rats were evaluated for weight loss, normal healing (colonic burst strength and hydroxyproline content at the anastomosis), and number and density of adhesions. Results The IC50 of the MK2 inhibitor peptide (22µM) was similar to that of the nonspecific small molecule Rottlerin (IC50=5µM). The MK2 inhibitor peptide was effective at suppressing IL-1β and TNF-α stimulated IL-6 expression in mesothelial cells. In vivo, the MK2 inhibitor peptide was effective as suppressing both the density and number of adhesions formed as a result of bowel anastomosis. Importantly, the peptide had no negative effect on normal healing. Conclusions In conclusion, the peptide inhibitor of MK2, MMI-0100, has the potential to significantly reduce inflammation through suppression of inflammatory cytokine expression and showed promise as a therapeutic for abdominal adhesions. PMID:21492875

  19. L1 cell adhesion molecule as a therapeutic target in cancer.

    PubMed

    Yu, Xinzhe; Yang, Feng; Fu, De-Liang; Jin, Chen

    2016-01-01

    L1 cell adhesion molecule (L1CAM) is the prototype member of the L1-family of closely related neural adhesion molecules. L1CAM is differentially expressed in the normal nervous system as well as pathological tissues and displays a wide range of biological activities. In human malignancies, L1CAM plays a vital role in tumor growth, invasion and metastasis. Recently, increasing evidence has suggested that L1CAM exerts a variety of functions at different steps of tumor progression through a series of signaling pathways. In addition, L1CAM has been identified as a promising target for cancer therapy by using synthetic and natural inhibitors. In this review, we provide an up-to-date overview of the role of L1CAM involved in cancers and the rationale for L1CAM as a novel molecular target for cancer therapy. PMID:26781307

  20. Air Pollution, Obesity, Genes, and Cellular Adhesion Molecules

    PubMed Central

    Madrigano, Jaime; Baccarelli, Andrea; Wright, Robert O.; Suh, Helen; Sparrow, David; Vokonas, Pantel S.; Schwartz, Joel

    2011-01-01

    Objectives Particulate matter (PM) has been associated with acute cardiovascular outcomes, but our understanding of the mechanism is incomplete. We examined the association between PM and cell adhesion molecules. We also investigated the modifying effect of genotype and phenotype variation to gain insight into the relevant biological pathways for this association. Methods We used mixed regression models to examine the association of PM2.5 and black carbon (BC) with serum concentrations of soluble Intercellular Adhesion Molecule (sICAM-1) and soluble Vascular Cell Adhesion Molecule (sVCAM-1), markers of endothelial function and inflammation, in a longitudinal study of 809 participants in the Normative Aging Study (1819 total observations). We also examined whether this association was modified by genotype, obesity, or diabetes status. Genes selected for analyses were either related to oxidative stress, endothelial function, lipid metabolism or metal processing. Results BC during the 2 days prior to blood draw was significantly associated with increased sVCAM-1 (4.5% increase per 1μg/m3 95% CI 1.1, 8.0). Neither pollutant was associated with sICAM-1. Larger effects of BCon sVCAM were seen in subjects with obesity (p=0.007) and who were GSTM1 null (p=0.02). Conclusions BC is associated with markers of endothelial function and inflammation. Genes related to oxidative defense may modify this association. PMID:19884647

  1. Soluble cell adhesion molecules in hypertriglyceridemia and potential significance on monocyte adhesion.

    PubMed

    Abe, Y; El-Masri, B; Kimball, K T; Pownall, H; Reilly, C F; Osmundsen, K; Smith, C W; Ballantyne, C M

    1998-05-01

    Hypertriglyceridemia may contribute to the development of atherosclerosis by increasing expression of cell adhesion molecules (CAMs). Although the cellular expression of CAMs is difficult to assess clinically, soluble forms of CAMs (sCAMs) are present in the circulation and may serve as markers for CAMs. In this study, we examined the association between sCAMs and other risk factors occurring with hypertriglyceridemia, the effect of triglyceride reduction on sCAM levels, and the role of soluble vascular cell adhesion molecule-1 (sVCAM-1) in monocyte adhesion in vitro. Compared with normal control subjects (n=20), patients with hypertriglyceridemia and low HDL (n=39) had significantly increased levels of soluble intercellular adhesion molecule-1 (sICAM-1) (316+/-28.8 versus 225+/-16.6 ng/mL), sVCAM-1 (743+/-52.2 versus 522+/-43.6 ng/mL), and soluble E-selectin (83+/-5.9 versus 49+/-3.6 ng/mL). ANCOVA showed that the higher sCAM levels in patients occurred independently of diabetes mellitus and other risk factors. In 27 patients who received purified n-3 fatty acid (Omacor) 4 g/d for > or =7 months, triglyceride level was reduced by 47+/-4.6%, sICAM-1 level was reduced by 9+/-3.4% (P=.02), and soluble E-selectin level was reduced by 16+/-3.2% (P<.0001), with the greatest reduction in diabetic patients. These results support previous in vitro data showing that disorders in triglyceride and HDL metabolism influence CAM expression and treatment with fish oils may alter vascular cell activation. In a parallel-plate flow chamber, recombinant sVCAM-1 at the concentration seen in patients significantly inhibited adhesion of monocytes to interleukin-1-stimulated cultured endothelial cells under conditions of flow by 27.5+/-7.2%. Thus, elevated sCAMs may negatively regulate monocyte adhesion.

  2. Small molecule phagocytosis inhibitors for immune cytopenias.

    PubMed

    Neschadim, Anton; Kotra, Lakshmi P; Branch, Donald R

    2016-08-01

    Immune cytopenias are conditions characterized by low blood cell counts, such as platelets in immune thrombocytopenia (ITP) and red blood cells in autoimmune hemolytic anemia (AIHA). Chronic ITP affects approximately 4 in 100,000 adults annually while AIHA is much less common. Extravascular phagocytosis and massive destruction of autoantibody-opsonized blood cells by macrophages in the spleen and liver are the hallmark of these conditions. Current treatment modalities for ITP and AIHA include the first-line use of corticosteroids; whereas, IVIg shows efficacy in ITP but not AIHA. One main mechanism of action by which IVIg treatment leads to the reduction in platelet destruction rates in ITP is thought to involve Fcγ receptor (FcγR) blockade, ultimately leading to the inhibition of extravascular platelet phagocytosis. IVIg, which is manufactured from the human plasma of thousands of donors, is a limited resource, and alternative treatments, particularly those based on bioavailable small molecules, are needed. In this review, we overview the pathophysiology of ITP, the role of Fcγ receptors, and the mechanisms of action of IVIg in treating ITP, and outline the efforts and progress towards developing novel, first-in-class inhibitors of phagocytosis as synthetic, small molecule substitutes for IVIg in ITP and other conditions where the pathobiology of the disease involves phagocytosis.

  3. Glycosylation inhibitors efficiently inhibit P-selectin-mediated cell adhesion to endothelial cells.

    PubMed

    Ghoshal, Pushpankur; Rajendran, Mythilypriya; Odo, Nadine; Ikuta, Tohru

    2014-01-01

    Adhesion molecules play a critical role in the adhesive interactions of multiple cell types in sickle cell disease (SCD). We previously showed that anti-P-selectin aptamer efficiently inhibits cell adhesion to endothelial cells (ECs) and permits SCD mice to survive hypoxic stress. In an effort to discover new mechanisms with which to inhibit P-selectin, we examined the role of glycosylation. P-selectin is a 90 kDa protein but was found to migrate as 90 and 140 kDa bands on gel electrophoresis. When P-selectin isolated from ECs was digested with peptide N-glycosidase F, but not O-glycosidase, the 140 kDa band was lost and the 90 kDa band was enhanced. Treatment of ECs with tunicamycin, an N-glycosylation inhibitor, suppressed CD62P (P-selectin) expression on the cell surface as well as the 140 kDa form in the cytoplasm. These results indicate that the 140 kDa band is N-glycosylated and glycosylation is critical for cell surface expression of P-selectin in ECs. Thrombin, which stimulates P-selectin expression on ECs, induced AKT phosphorylation, whereas tunicamycin inhibited AKT phosphorylation, suggesting that AKT signaling is involved in the tunicamycin-mediated inhibition of P-selectin expression. Importantly, the adhesion of sickle red blood cells (sRBCs) and leukocytes to ECs induced by thrombin or hypoxia was markedly inhibited by two structurally distinct glycosylation inhibitors; the levels of which were comparable to that of a P-selectin monoclonal antibody which most strongly inhibited cell adhesion in vivo. Knockdown studies of P-selectin using short-hairpin RNAs in ECs suppressed sRBC adhesion, indicating a legitimate role for P-selectin in sRBC adhesion. Together, these results demonstrate that P-selectin expression on ECs is regulated in part by glycosylation mechanisms and that glycosylation inhibitors efficiently reduce the adhesion of sRBCs and leukocytes to ECs. Glycosylation inhibitors may lead to a novel therapy which inhibits cell adhesion in SCD.

  4. The ubiquitous neural cell adhesion molecule (N-CAM).

    PubMed

    Weledji, Elroy P; Assob, Jules C

    2014-09-01

    Adhesive interactions are important for cell trafficking, differentiation, function and tissue differentiation. Neural cell adhesion molecule (NCAM) is involved in a diverse range of contact-mediated interactions among neurons, astrocytes, oligodendrocytes, and myotubes. It is widely but transiently expressed in many tissues early in embryogenesis. Four main isoforms exist but there are many other variants resulting from alternative splicing and post-translational modifications. This review discusses the actions and association of N-CAM and variants, PSA CAM. L1CAM and receptor tyrosine kinase. Their interactions with the interstitial cells of Cajal - the pacemaker cells of the gut in the manifestation of gut motility disorders, expression in carcinomas and mesenchymal tumours are discussed. PMID:25568792

  5. Small Molecule Inhibitors of Anthrax Lethal Factor Toxin

    PubMed Central

    Williams, John D.; Khan, Atiyya R.; Cardinale, Steven C.; Butler, Michelle M.; Bowlin, Terry L.; Peet, Norton P.

    2014-01-01

    This manuscript describes the preparation of new small molecule inhibitors of Bacillus anthracis lethal factor. Our starting point was the symmetrical, bis-quinolinyl compound 1 (NSC 12155). Optimization of one half of this molecule led to new LF inhibitors that were desymmetrized to afford more drug-like compounds. PMID:24290062

  6. Analysis of Adhesion Molecules and Basement Membrane Contributions to Synaptic Adhesion at the Drosophila Embryonic NMJ

    PubMed Central

    Koper, Andre; Schenck, Annette; Prokop, Andreas

    2012-01-01

    Synapse formation and maintenance crucially underlie brain function in health and disease. Both processes are believed to depend on cell adhesion molecules (CAMs). Many different classes of CAMs localise to synapses, including cadherins, protocadherins, neuroligins, neurexins, integrins, and immunoglobulin adhesion proteins, and further contributions come from the extracellular matrix and its receptors. Most of these factors have been scrutinised by loss-of-function analyses in animal models. However, which adhesion factors establish the essential physical links across synaptic clefts and allow the assembly of synaptic machineries at the contact site in vivo is still unclear. To investigate these key questions, we have used the neuromuscular junction (NMJ) of Drosophila embryos as a genetically amenable model synapse. Our ultrastructural analyses of NMJs lacking different classes of CAMs revealed that loss of all neurexins, all classical cadherins or all glutamate receptors, as well as combinations between these or with a Laminin deficiency, failed to reveal structural phenotypes. These results are compatible with a view that these CAMs might have no structural role at this model synapse. However, we consider it far more likely that they operate in a redundant or well buffered context. We propose a model based on a multi-adaptor principle to explain this phenomenon. Furthermore, we report a new CAM-independent adhesion mechanism that involves the basement membranes (BM) covering neuromuscular terminals. Thus, motorneuronal terminals show strong partial detachment of the junction when BM-to-cell surface attachment is impaired by removing Laminin A, or when BMs lose their structural integrity upon loss of type IV collagens. We conclude that BMs are essential to tie embryonic motorneuronal terminals to the muscle surface, lending CAM-independent structural support to their adhesion. Therefore, future developmental studies of these synaptic junctions in Drosophila need

  7. Expression of intercellular adhesion molecule-1 in rat heart with ischemia/reperfusion and limitation of infarct size by treatment with antibodies against cell adhesion molecules.

    PubMed Central

    Yamazaki, T.; Seko, Y.; Tamatani, T.; Miyasaka, M.; Yagita, H.; Okumura, K.; Nagai, R.; Yazaki, Y.

    1993-01-01

    To elucidate the mechanism(s) of myocardial reperfusion injury, we investigated the roles of cell adhesion molecules on both leukocytes and vascular endothelial cells in the reperfused myocardia. We found that within 2 hours after reperfusion leukocytes began to infiltrate into the rat myocardia subjected to 30 minutes of ischemia and clarified, for the first time, that the expression of intercellular adhesion molecule-1 was enhanced on the capillary and venous endothelial cells from 8 to 96 hours after the start of reperfusion. Furthermore, pretreatment with individual monoclonal antibodies against cell adhesion molecules (CD11a, CD11bc, CD18, and intercellular adhesion molecule-1) reduced not only the infiltration of leukocytes but also the area of infarction in the reperfused hearts. These observations suggest that cell adhesion molecules play a critical role in the pathogenesis of myocardial reperfusion injury. Images Figure 2 Figure 3 Figure 4 PMID:8102030

  8. Direct observation of catch bonds involving cell-adhesion molecules

    NASA Astrophysics Data System (ADS)

    Marshall, Bryan T.; Long, Mian; Piper, James W.; Yago, Tadayuki; McEver, Rodger P.; Zhu, Cheng

    2003-05-01

    Bonds between adhesion molecules are often mechanically stressed. A striking example is the tensile force applied to selectin-ligand bonds, which mediate the tethering and rolling of flowing leukocytes on vascular surfaces. It has been suggested that force could either shorten bond lifetimes, because work done by the force could lower the energy barrier between the bound and free states (`slip'), or prolong bond lifetimes by deforming the molecules such that they lock more tightly (`catch'). Whereas slip bonds have been widely observed, catch bonds have not been demonstrated experimentally. Here, using atomic force microscopy and flow-chamber experiments, we show that increasing force first prolonged and then shortened the lifetimes of P-selectin complexes with P-selectin glycoprotein ligand-1, revealing both catch and slip bond behaviour. Transitions between catch and slip bonds might explain why leukocyte rolling on selectins first increases and then decreases as wall shear stress increases. This dual response to force provides a mechanism for regulating cell adhesion under conditions of variable mechanical stress.

  9. Cooperative inhibitory effects of antisense oligonucleotide of cell adhesion molecules and cimetidine on cancer cell adhesion

    PubMed Central

    Tang, Nan-Hong; Chen, Yan-Ling; Wang, Xiao-Qian; Li, Xiu-Jin; Yin, Feng-Zhi; Wang, Xiao-Zhong

    2004-01-01

    AIM: To explore the cooperative effects of antisense oligonucleotide (ASON) of cell adhesion molecules and cimetidine on the expression of E-selectin and ICAM-1 in endothelial cells and their adhesion to tumor cells. METHODS: After treatment of endothelial cells with ASON and/or cimetidine and induction with TNF-α, the protein and mRNA changes of E-selectin and ICAM-1 in endothelial cells were examined by flow cytometry and RT-PCR, respectively. The adhesion rates of endothelial cells to tumor cells were measured by cell adhesion experiment. RESULTS: In comparison with TNF-α inducing group, lipo-ASON and lipo-ASON/cimetidine could significantly decrease the protein and mRNA levels of E-selectin and ICAM-1 in endothelial cells, and lipo-ASON/cimetidine had most significant inhibitory effect on E-selectin expression (from 36.37 ± 1.56% to 14.23 ± 1.07%, P < 0.001). Meanwhile, cimetidine alone could inhibit the expression of E-selectin (36.37 ± 1.56% vs 27.2 ± 1.31%, P < 0.001), but not ICAM-1 (69.34 ± 2.50% vs 68.07 ± 2.10%, P > 0.05)and the two kinds of mRNA, either. Compared with TNF-α inducing group, the rate of adhesion was markedly decreased in lipo-E-selectin ASON and lipo-E-selectin ASON/cimetidine treated groups(P < 0.05), and lipo-E-selectin ASON/cimetidine worked better than lipo-E-selectin ASON alone except for HepG2/ECV304 group (P < 0.05). However, the decrease of adhesion was not significant in lipo-ICAM-1 ASON and lipo-ICAM-1 ASON/cimetidine treated groups except for HepG2/ECV304 group (P > 0.05). CONCLUSION: These data demonstrate that ASON in combination with cimetidine in vitro can significantly reduce the adhesion between endothelial cells and hepatic or colorectal cancer cells, which is stronger than ASON or cimetidine alone. This study provides some useful proofs for gene therapy of antiadhesion. PMID:14695770

  10. Exenatide Alters Gene Expression of Neural Cell Adhesion Molecule (NCAM), Intercellular Cell Adhesion Molecule (ICAM), and Vascular Cell Adhesion Molecule (VCAM) in the Hippocampus of Type 2 Diabetic Model Mice.

    PubMed

    Gumuslu, Esen; Cine, Naci; Ertan Gökbayrak, Merve; Mutlu, Oguz; Komsuoglu Celikyurt, Ipek; Ulak, Guner

    2016-01-01

    BACKGROUND Glucagon-like peptide-1 (GLP-1), a potent and selective agonist for the GLP-1 receptor, ameliorates the symptoms of diabetes through stimulation of insulin secretion. Exenatide is a potent and selective agonist for the GLP-1 receptor. Cell adhesion molecules are members of the immunoglobulin superfamily and are involved in synaptic rearrangements in the mature brain. MATERIAL AND METHODS The present study demonstrated the effects of exenatide treatment (0.1 µg/kg, subcutaneously, twice daily for 2 weeks) on the gene expression levels of cell adhesion molecules, neural cell adhesion molecule (NCAM), intercellular cell adhesion molecule (ICAM), and vascular cell adhesion molecule (VCAM) in the brain tissue of diabetic BALB/c male mice by real-time quantitative polymerase chain reaction (PCR). Diabetes was induced by streptozotocin/nicotinamide (STZ-NA) injection to male mice. RESULTS The results of this study revealed that hippocampal gene expression of NCAM, ICAM, and VCAM were found to be up-regulated in STZ-NA-induced diabetic mice compared to those of controls. A significant decrease in the gene expression levels of NCAM, ICAM, and VCAM were determined after 2 weeks of exenatide administration. CONCLUSIONS Cell adhesion molecules may be involved in the molecular mechanism of diabetes. Exenatide has a strong beneficial action in managing diabetes induced by STZ/NA by altering gene expression of NCAM, ICAM, and VCAM. PMID:27465247

  11. Exenatide Alters Gene Expression of Neural Cell Adhesion Molecule (NCAM), Intercellular Cell Adhesion Molecule (ICAM), and Vascular Cell Adhesion Molecule (VCAM) in the Hippocampus of Type 2 Diabetic Model Mice

    PubMed Central

    Gumuslu, Esen; Cine, Naci; Gökbayrak, Merve Ertan; Mutlu, Oguz; Celikyurt, Ipek Komsuoglu; Ulak, Guner

    2016-01-01

    Background Glucagon-like peptide-1 (GLP-1), a potent and selective agonist for the GLP-1 receptor, ameliorates the symptoms of diabetes through stimulation of insulin secretion. Exenatide is a potent and selective agonist for the GLP-1 receptor. Cell adhesion molecules are members of the immunoglobulin superfamily and are involved in synaptic rearrangements in the mature brain. Material/Methods The present study demonstrated the effects of exenatide treatment (0.1 μg/kg, subcutaneously, twice daily for 2 weeks) on the gene expression levels of cell adhesion molecules, neural cell adhesion molecule (NCAM), intercellular cell adhesion molecule (ICAM), and vascular cell adhesion molecule (VCAM) in the brain tissue of diabetic BALB/c male mice by real-time quantitative polymerase chain reaction (PCR). Diabetes was induced by streptozotocin/nicotinamide (STZ-NA) injection to male mice. Results The results of this study revealed that hippocampal gene expression of NCAM, ICAM, and VCAM were found to be up-regulated in STZ-NA-induced diabetic mice compared to those of controls. A significant decrease in the gene expression levels of NCAM, ICAM, and VCAM were determined after 2 weeks of exenatide administration. Conclusions Cell adhesion molecules may be involved in the molecular mechanism of diabetes. Exenatide has a strong beneficial action in managing diabetes induced by STZ/NA by altering gene expression of NCAM, ICAM, and VCAM. PMID:27465247

  12. Carbohydrate ligands for endothelial - Leukocyte adhesion molecule 1

    SciTech Connect

    Tiemeyer, M.; Swiedler, S.J.; Ishihara, Masayuki; Moreland, M.; Schweingruber, H.; Hirtzer, P.; Brandley, B.K. )

    1991-02-15

    The acute inflammatory response requires that circulating leukocytes bind to and penetrate the vascular wall to access the site of injury. Several receptors have been implicated in this interaction, including a family of putative carbohydrate-binding proteins. The authors report here the identification of an endogenous carbohydrate ligand for one of these receptors, endothelial-leukocyte adhesion molecule 1 (ELAM-1). Radiolabeled COS cells transfected with a plasmid containing the cDNA for ELAM-1 were used as probes to screen glycolipids extracted from human leukocytes. COS cells transfected with this plasmid adhered to a subset of sialylated glycolipids resolved on TLC plates or adsorbed on polyvinyl chloride microtiter wells. Adhesion to these glycolipids required calcium but was not inhibited by heparin, chondroitin sulfate, keratan sulfate, or yeast phosphomannan. Monosaccharide composition, linkage analysis, and fast atom bombardment mass spectrometry of the glycolipids indicate that the ligands for ELAM-1 are terminally sialylated lactosylceramides with a variable number of N-acetyllactosamine repeats and at least one fucosylated N-acetylglucosamine residue.

  13. Cell adhesion molecule control of planar spindle orientation.

    PubMed

    Tuncay, Hüseyin; Ebnet, Klaus

    2016-03-01

    Polarized epithelial cells align the mitotic spindle in the plane of the sheet to maintain tissue integrity and to prevent malignant transformation. The orientation of the spindle apparatus is regulated by the immobilization of the astral microtubules at the lateral cortex and depends on the precise localization of the dynein-dynactin motor protein complex which captures microtubule plus ends and generates pulling forces towards the centrosomes. Recent developments indicate that signals derived from intercellular junctions are required for the stable interaction of the dynein-dynactin complex with the cortex. Here, we review the molecular mechanisms that regulate planar spindle orientation in polarized epithelial cells and we illustrate how different cell adhesion molecules through distinct and non-overlapping mechanisms instruct the cells to align the mitotic spindle in the plane of the sheet. PMID:26698907

  14. The role of endothelial cell adhesion molecules P-selectin, E-selectin and intercellular adhesion molecule-1 in leucocyte recruitment induced by exogenous methylglyoxal.

    PubMed

    Su, Yang; Lei, Xi; Wu, Lingyun; Liu, Lixin

    2012-09-01

    Methylglyoxal (MG) is a reactive dicarbonyl metabolite formed during glucose, protein and fatty acid metabolism. In hyperglycaemic conditions, increased MG level has been linked to the development of diabetes and its vascular complications at the macrovascular and microvascular levels where inflammation plays a role. To study the mechanism of MG-induced inflammation in vivo, we applied MG locally to healthy mice and used intravital microscopy to investigate the role of endothelial cell adhesion molecules in MG-induced leucocyte recruitment in cremasteric microvasculature. Administration of MG (25 and 50 mg/kg) to the tissue dose-dependently induced leucocyte recruitment at 4.0-5.5 hr, with 84-92% recruited cells being neutrophils. Such MG treatment up-regulated the expression of endothelial cell adhesion molecules P-selectin, E-selectin, intercellular adhesion molecule-1, but not vascular cell adhesion molecule-1. Activation of the nuclear factor-κB signalling pathway contributed to MG-induced up-regulation of these adhesion molecules and leucocyte recruitment. The role of the up-regulated endothelial cell adhesion molecules in MG-induced leucocyte recruitment was determined by applying specific functional blocking antibodies to MG-treated animals and observing changes in leucocyte recruitment parameters. Our data demonstrate that the up-regulation of P-selectin, E-selectin and intercellular adhesion molecule-1 contributes to the increased leucocyte rolling flux, reduced leucocyte rolling velocity, and increased leucocyte adhesion, respectively. Our results reveal the role of endothelial cell adhesion molecules in MG-induced leucocyte recruitment in microvasculature, an inflammatory condition related to diabetic vascular complications.

  15. The role of endothelial cell adhesion molecules P-selectin, E-selectin and intercellular adhesion molecule-1 in leucocyte recruitment induced by exogenous methylglyoxal

    PubMed Central

    Su, Yang; Lei, Xi; Wu, Lingyun; Liu, Lixin

    2012-01-01

    Methylglyoxal (MG) is a reactive dicarbonyl metabolite formed during glucose, protein and fatty acid metabolism. In hyperglycaemic conditions, increased MG level has been linked to the development of diabetes and its vascular complications at the macrovascular and microvascular levels where inflammation plays a role. To study the mechanism of MG-induced inflammation in vivo, we applied MG locally to healthy mice and used intravital microscopy to investigate the role of endothelial cell adhesion molecules in MG-induced leucocyte recruitment in cremasteric microvasculature. Administration of MG (25 and 50 mg/kg) to the tissue dose-dependently induced leucocyte recruitment at 4·0–5·5 hr, with 84–92% recruited cells being neutrophils. Such MG treatment up-regulated the expression of endothelial cell adhesion molecules P-selectin, E-selectin, intercellular adhesion molecule-1, but not vascular cell adhesion molecule-1. Activation of the nuclear factor-κB signalling pathway contributed to MG-induced up-regulation of these adhesion molecules and leucocyte recruitment. The role of the up-regulated endothelial cell adhesion molecules in MG-induced leucocyte recruitment was determined by applying specific functional blocking antibodies to MG-treated animals and observing changes in leucocyte recruitment parameters. Our data demonstrate that the up-regulation of P-selectin, E-selectin and intercellular adhesion molecule-1 contributes to the increased leucocyte rolling flux, reduced leucocyte rolling velocity, and increased leucocyte adhesion, respectively. Our results reveal the role of endothelial cell adhesion molecules in MG-induced leucocyte recruitment in microvasculature, an inflammatory condition related to diabetic vascular complications. PMID:22681228

  16. An extracellular adhesion molecule complex patterns dendritic branching and morphogenesis.

    PubMed

    Dong, Xintong; Liu, Oliver W; Howell, Audrey S; Shen, Kang

    2013-10-10

    Robust dendrite morphogenesis is a critical step in the development of reproducible neural circuits. However, little is known about the extracellular cues that pattern complex dendrite morphologies. In the model nematode Caenorhabditis elegans, the sensory neuron PVD establishes stereotypical, highly branched dendrite morphology. Here, we report the identification of a tripartite ligand-receptor complex of membrane adhesion molecules that is both necessary and sufficient to instruct spatially restricted growth and branching of PVD dendrites. The ligand complex SAX-7/L1CAM and MNR-1 function at defined locations in the surrounding hypodermal tissue, whereas DMA-1 acts as the cognate receptor on PVD. Mutations in this complex lead to dramatic defects in the formation, stabilization, and organization of the dendritic arbor. Ectopic expression of SAX-7 and MNR-1 generates a predictable, unnaturally patterned dendritic tree in a DMA-1-dependent manner. Both in vivo and in vitro experiments indicate that all three molecules are needed for interaction. PMID:24120131

  17. Adhesion Molecule Expression in Human Endothelial Cells under Simulated Microgravity

    NASA Astrophysics Data System (ADS)

    Rudimov, E. G.; Andreeva, E. R.; Buravkova, L. B.

    2013-02-01

    High gravisensitivity of endothelium is now well recognized. Therefore, the microgravity can be one of the main factors affecting the endothelium in space flight. In this work we studied the effects of gravity vector randomization (3D-clinorotation in RPM) on the viability of endothelial cells from human umbilical vein (HUVEC) and the expression of adhesion molecules on its surface. After RPM exposure, HUVEC conditioning medium was collected for cytokines evaluation, a part of vials was used for immunocytochemistry and other one - for cytofluorimetric analysis of ICAM-I, VCAM-I, PECAM-I, E-selectin, Endoglin, VE-cadherin expression. The viability of HUVEC and constitutive expression of EC marker molecules PECAM-I and Endoglin were similar in all experimental groups both after 6 and 24 hrs of exposure. There were no differences in ICAM-I and E-selectin expression on HUVEC in 3 groups after 6 hrs of exposure. 24 hrs incubation has provoked decrease in ICAM-I and E-selectin expression. Thus, gravity vector randomization can lead to the disruption of ECs monolayer.

  18. Heterogeneity of cell adhesion molecules in the developing nervous system

    SciTech Connect

    Williams, R.K.

    1985-01-01

    Cell-surface molecules, especially glycoproteins, are believed to mediate interactions between developing neurons and their environment. These interactions include pathfinding by growing processes, recognition of appropriate targets, and formation of synaptic structures. In order to identify neuronal cell-surface molecules, monoclonal antibodies (Mab's) were prepared against synaptic fractions from adult rat brain. From this group three monoclonal antibodies, designated 3C5.59, 3G5.34, and 3G6.41, that react with cell-surface antigens of embryonic neurons were selected for further study. In immunofluoresence experiments each of these antibodies strongly reacted with the processes of cultured granule cell neurons, the major class of small cerebellar neurons, cultured from developing rat cerebellum. Mab's 3C5.59 and 3G5.34 reacted only with neurons in the cerebellar cultures. Mab 3G6.41, however, also reacted with cultured brain astrocytes. On frozen sections Mab's 3G5.34 and 3G6.41 also strongly stained the molecular layer, the site of active granule cell axon growth, in the developing cerebellum. Monoclonal and polyclonal antibodies specific for the neural cell adhesion molecule (N-CAM) were used to compare the two glycoproteins recognized by Mab 3G6.41 with N-CAM. Band 1, another large neuronal cell-surface glycoprotein was originally identified in mouse N18 neuroblastoma cells. In this study /sup 125/I-labeled N18-derived band 1 was tested for binding to 9 plant lectins and Limulus polyphemus agglutinin coupled to agarose beads. Band 1 solubilized from brain also specifically bound to LCA-agarose, indicating that mannose containing sugar moieties are present on band 1 from brain.

  19. Allosteric Small-Molecule Inhibitors of the AKT Kinase

    NASA Astrophysics Data System (ADS)

    Dalafave, D. S.

    This research addresses computational design of small druglike molecules for possible anticancer applications. AKT and SGK are kinases that control important cellular functions. They are highly homologous, having similar activators and targets. Cancers with increased SGK activity may develop resistance to AKT-specific inhibitors. Our goal was to design new molecules that would bind both AKT and SGK, thus preventing the development of drug resistance. Most kinase inhibitors target the kinase ATP-binding site. However, the high similarity in this site among kinases makes it difficult to target specifically. Furthermore, mutations in this site can cause resistance to ATP-competitive kinase inhibitors. We used existing AKT inhibitors as initial templates to design molecules that could potentially bind the allosteric sites of both AKT and SGK. Molecules with no implicit toxicities and optimal drug-like properties were used for docking studies. Binding energies of the stable complexes that the designed molecules formed with AKT and SGK were calculated. Possible applications of the designed putative inhibitors against cancers with overexpressed AKT/SGK is discussed.

  20. Purification, composition, and structure of macrophage adhesion molecule

    SciTech Connect

    Remold-O'Donnell, E.; Savage, B.

    1988-01-12

    Macrophage adhesion molecule (MAM) is a surface heterodimer consisting of the trypsin- and plasmin-sensitive glycopeptide gp160 (MAM-..cap alpha..) and the glycopeptide gp93 (MAM-..beta..). MAM, which is the guinea pig analog of Mo1 and Mac-1, was purified from detergent lysates of peritoneal neutrophils by lentil lectin chromatography and M2-antibody chromatography. The pure heterodimer molecule was dissociated by acidic conditions (pH 3.5), and MAM-..cap alpha.. and MAM-..beta.. were separated by M7-antibody chromatography. MAM-..beta.. is an approx. 640 amino acid residue polypeptide with exceptionally high cysteine content. At 7.2 residues per 100 amino acids, Cys/2 of MAM-..beta.. is more than 3 times the mean for 200 purified proteins. Reactivity with six ..beta..-subunit-specific /sup 125/I-labeled monoclonal antibodies recognizing at least four epitopes demonstrated that intrapeptide disulfide bonds are required to maintain the structure of MAM-..beta... All six antibodies failed to react when MAM-..beta.. was treated with reducing agents. MAM-..beta.. is 18% carbohydrate; the major monosaccharides are mannose, N-acetylglucosamine, galactose, and sialic acid. MAM-..beta.. is estimated to contain five to six N-linked carbohydrate units. MAM-..cap alpha.. is an approx. 1100-residue polypeptide with lower Cys/2 content (2.0 residues per 100 amino acid residues). MAM-..cap alpha.. is 21% carbohydrate. The major monosaccharides are mannose, N-acetylglucosamine, galactose, and sialic acid; the mannose content is higher in MAM-..cap alpha.. than MAM-..beta.. is estimated to contain 12 N-linked carbohydrate units.

  1. FDA-approved small-molecule kinase inhibitors.

    PubMed

    Wu, Peng; Nielsen, Thomas E; Clausen, Mads H

    2015-07-01

    Kinases have emerged as one of the most intensively pursued targets in current pharmacological research, especially for cancer, due to their critical roles in cellular signaling. To date, the US FDA has approved 28 small-molecule kinase inhibitors, half of which were approved in the past 3 years. While the clinical data of these approved molecules are widely presented and structure-activity relationship (SAR) has been reported for individual molecules, an updated review that analyzes all approved molecules and summarizes current achievements and trends in the field has yet to be found. Here we present all approved small-molecule kinase inhibitors with an emphasis on binding mechanism and structural features, summarize current challenges, and discuss future directions in this field.

  2. Gingipains from Porphyromonas gingivalis W83 induce cell adhesion molecule cleavage and apoptosis in endothelial cells.

    PubMed

    Sheets, Shaun M; Potempa, Jan; Travis, James; Casiano, Carlos A; Fletcher, Hansel M

    2005-03-01

    The presence of Porphyromonas gingivalis in the periodontal pocket and the high levels of gingipain activity detected in gingival crevicular fluid could implicate a role for gingipains in the destruction of the highly vascular periodontal tissue. To explore the effects of these proteases on endothelial cells, we exposed bovine coronary artery endothelial cells and human microvascular endothelial cells to gingipain-active extracellular protein preparations and/or purified gingipains from P. gingivalis. Treated cells exhibited a rapid loss of cell adhesion properties that was followed by apoptotic cell death. Cleavage of N- and VE-cadherin and integrin beta1 was observed in immunoblots of cell lysates. There was a direct correlation between the kinetics of cleavage of N- and VE-cadherin and loss of cell adhesion properties. Loss of cell adhesion, as well as N- and VE-cadherin and integrin beta1 cleavage, could be inhibited or significantly delayed by preincubation of P. gingivalis W83 gingipain-active extracellular extracts with the cysteine protease inhibitor Nalpha-p-tosyl-l-lysine chloromethylketone. Furthermore, purified gingipains also induced endothelial cell detachment and apoptosis. Apoptosis-associated events, including annexin V positivity, caspase-3 activation, and cleavage of the caspase substrates poly(ADP-ribose) polymerase and topoisomerase I (Topo I), were observed in endothelial cells after detachment. All of the effects observed were correlated with the different levels of cysteine-dependent proteolytic activity of the extracts tested. Taken together, these results indicate that gingipains from P. gingivalis can alter cell adhesion molecules and induce endothelial cell death, which could have implications for the pathogenicity of this organism. PMID:15731052

  3. Small Molecule Agonists of Cell Adhesion Molecule L1 Mimic L1 Functions In Vivo.

    PubMed

    Kataria, Hardeep; Lutz, David; Chaudhary, Harshita; Schachner, Melitta; Loers, Gabriele

    2016-09-01

    Lack of permissive mechanisms and abundance of inhibitory molecules in the lesioned central nervous system of adult mammals contribute to the failure of functional recovery after injury, leading to severe disabilities in motor functions and pain. Peripheral nerve injury impairs motor, sensory, and autonomic functions, particularly in cases where nerve gaps are large and chronic nerve injury ensues. Previous studies have indicated that the neural cell adhesion molecule L1 constitutes a viable target to promote regeneration after acute injury. We screened libraries of known drugs for small molecule agonists of L1 and evaluated the effect of hit compounds in cell-based assays in vitro and in mice after femoral nerve and spinal cord injuries in vivo. We identified eight small molecule L1 agonists and showed in cell-based assays that they stimulate neuronal survival, neuronal migration, and neurite outgrowth and enhance Schwann cell proliferation and migration and myelination of neurons in an L1-dependent manner. In a femoral nerve injury mouse model, enhanced functional regeneration and remyelination after application of the L1 agonists were observed. In a spinal cord injury mouse model, L1 agonists improved recovery of motor functions, being paralleled by enhanced remyelination, neuronal survival, and monoaminergic innervation, reduced astrogliosis, and activation of microglia. Together, these findings suggest that application of small organic compounds that bind to L1 and stimulate the beneficial homophilic L1 functions may prove to be a valuable addition to treatments of nervous system injuries. PMID:26253722

  4. Identification and Characterization of a Small Molecule Inhibitor of Formin-Mediated Actin Assembly

    PubMed Central

    Rizvi, Syed A.; Neidt, Erin M.; Cui, Jiayue; Feiger, Zach; Skau, Colleen T.; Gardel, Margaret L.; Kozmin, Sergey A.; Kovar, David R.

    2009-01-01

    SUMMARY Formins stimulate actin filament assembly for fundamental cellular processes including division, adhesion, establishing polarity and motility. A formin inhibitor would be useful because most cells express multiple formins whose functions are not known, and because metastatic tumor formation depends upon the deregulation of formin-dependent processes. We identified a general small molecule inhibitor of formin homology 2 domains (SMIFH2) by screening compounds for the ability to prevent formin-mediated actin assembly in vitro. SMIFH2 targets formins from evolutionarily diverse organisms including yeast, nematode worm and mice, with a half-maximal inhibitor concentration of ~5 to 15 μM. SMIFH2 prevents both formin nucleation and processive barbed-end elongation, and decreases formin’s affinity for the barbed end. Furthermore, low micromolar concentrations of SMIFH2 disrupt formin-dependent, but not Arp2/3 complex-dependent, actin cytoskeletal structures in fission yeast and mammalian NIH 3T3 fibroblasts. PMID:19942139

  5. Omentin inhibits TNF-{alpha}-induced expression of adhesion molecules in endothelial cells via ERK/NF-{kappa}B pathway

    SciTech Connect

    Zhong, Xia; Li, Xiaonan; Liu, Fuli; Tan, Hui; Shang, Deya

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer Omentin inhibited TNF-{alpha}-induced adhesion of THP-1 cells to HUVECs. Black-Right-Pointing-Pointer Omentin reduces expression of ICAM-1 and VCAM-1 induced by TNF-{alpha} in HUVECs. Black-Right-Pointing-Pointer Omentin inhibits TNF-{alpha}-induced ERK and NF-{kappa}B activation in HUVECs. Black-Right-Pointing-Pointer Omentin supreeses TNF-{alpha}-induced expression of ICAM-1 and VCAM-1 via ERK/NF-{kappa}B pathway. -- Abstract: In the present study, we investigated whether omentin affected the expression of intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in tumor necrosis factor-{alpha} (TNF-{alpha}) induced human umbilical vein endothelial cells (HUVECs). Our data showed that omentin decreased TNF-{alpha}-induced expression of ICAM-1 and VCAM-1 in HUVECs. In addition, omentin inhibited TNF-{alpha}-induced adhesion of THP-1 cells to HUVECs. Further, we found that omentin inhibited TNF-{alpha}-activated signal pathway of nuclear factor-{kappa}B (NF-{kappa}B) by preventing NF-{kappa}B inhibitory protein (I{kappa}B{alpha}) degradation and NF-{kappa}B/DNA binding activity. Omentin pretreatment significantly inhibited TNF-{alpha}-induced ERK activity and ERK phosphorylation in HUVECs. Pretreatment with PD98059 suppressed TNF-{alpha}-induced NF-{kappa}B activity. Omentin, NF-kB inhibitor (BAY11-7082) and ERK inhibitor (PD98059) reduced the up-regulation of ICAM-1 and VCAM-1 induced by TNF-{alpha}. These results suggest that omentin may inhibit TNF-{alpha}-induced expression of adhesion molecules in endothelial cells via blocking ERK/NF-{kappa}B pathway.

  6. New families of adhesion molecules play a vital role in platelet functions.

    PubMed

    Parmentier, S; Kaplan, C; Catimel, B; McGregor, J L

    1990-07-01

    Adhesion molecules play a crucial part in cell-matrix and in cell-cell interactions. These interactions, which are essential to the body's defense processes, involve adhesion molecules belonging to different families: integrins, immunoglobulins and selectins. Integrins are expressed by a large number of tissues, whereas other adhesion molecule families are restricted to a small number of cell types. A recent symposium dealt with the recruitment of circulating platelets at specific sites, their adhesion to extracellular matrix components and their activation by agonists leading to aggregation or attachment to other cells. These events, supporting hemostasis and thrombosis, involve integrins, selectins and other adhesion molecules. This report focuses on newly reported integrins (GPIa, GPIc, GPIIa), selectins (GMP-140) and GPIIIb, previously known as 'minor' surface oriented platelet glycoproteins. Major membrane glycoproteins such as GPIIb-IIIa (an integrin) and GPIb, which also play a vital role in platelet functions, have been extensively reviewed elsewhere.

  7. Reciprocal Interactions between Cell Adhesion Molecules of the Immunoglobulin Superfamily and the Cytoskeleton in Neurons

    PubMed Central

    Leshchyns'ka, Iryna; Sytnyk, Vladimir

    2016-01-01

    Cell adhesion molecules of the immunoglobulin superfamily (IgSF) including the neural cell adhesion molecule (NCAM) and members of the L1 family of neuronal cell adhesion molecules play important functions in the developing nervous system by regulating formation, growth and branching of neurites, and establishment of the synaptic contacts between neurons. In the mature brain, members of IgSF regulate synapse composition, function, and plasticity required for learning and memory. The intracellular domains of IgSF cell adhesion molecules interact with the components of the cytoskeleton including the submembrane actin-spectrin meshwork, actin microfilaments, and microtubules. In this review, we summarize current data indicating that interactions between IgSF cell adhesion molecules and the cytoskeleton are reciprocal, and that while IgSF cell adhesion molecules regulate the assembly of the cytoskeleton, the cytoskeleton plays an important role in regulation of the functions of IgSF cell adhesion molecules. Reciprocal interactions between NCAM and L1 family members and the cytoskeleton and their role in neuronal differentiation and synapse formation are discussed in detail. PMID:26909348

  8. Reciprocal Interactions between Cell Adhesion Molecules of the Immunoglobulin Superfamily and the Cytoskeleton in Neurons.

    PubMed

    Leshchyns'ka, Iryna; Sytnyk, Vladimir

    2016-01-01

    Cell adhesion molecules of the immunoglobulin superfamily (IgSF) including the neural cell adhesion molecule (NCAM) and members of the L1 family of neuronal cell adhesion molecules play important functions in the developing nervous system by regulating formation, growth and branching of neurites, and establishment of the synaptic contacts between neurons. In the mature brain, members of IgSF regulate synapse composition, function, and plasticity required for learning and memory. The intracellular domains of IgSF cell adhesion molecules interact with the components of the cytoskeleton including the submembrane actin-spectrin meshwork, actin microfilaments, and microtubules. In this review, we summarize current data indicating that interactions between IgSF cell adhesion molecules and the cytoskeleton are reciprocal, and that while IgSF cell adhesion molecules regulate the assembly of the cytoskeleton, the cytoskeleton plays an important role in regulation of the functions of IgSF cell adhesion molecules. Reciprocal interactions between NCAM and L1 family members and the cytoskeleton and their role in neuronal differentiation and synapse formation are discussed in detail. PMID:26909348

  9. A novel small-molecule inhibitor of 3-phosphoglycerate dehydrogenase.

    PubMed

    Mullarky, Edouard; Lairson, Luke L; Cantley, Lewis C; Lyssiotis, Costas A

    2016-07-01

    Serine metabolism is likely to play a critical role in cancer cell growth. A recent study reports the identification of a novel small-molecule inhibitor of serine synthesis that targets 3-phosphoglycerate dehydrogenase (PHGDH), the first enzyme of the serine synthesis pathway, and selectively abrogates the proliferation of PHGDH overexpressing breast cancer cells. PMID:27652319

  10. Homophilic Adhesion Mechanism of Neurofascin, a Member of the L1 Family of Neural Cell Adhesion Molecules

    SciTech Connect

    Liu, Heli; Focia, Pamela J.; He, Xiaolin

    2012-02-13

    The L1 family neural cell adhesion molecules play key roles in specifying the formation and remodeling of the neural network, but their homophilic interaction that mediates adhesion is not well understood. We report two crystal structures of a dimeric form of the headpiece of neurofascin, an L1 family member. The four N-terminal Ig-like domains of neurofascin form a horseshoe shape, akin to several other immunoglobulin superfamily cell adhesion molecules such as hemolin, axonin, and Dscam. The neurofascin dimer, captured in two crystal forms with independent packing patterns, reveals a pair of horseshoes in trans-synaptic adhesion mode. The adhesion interaction is mediated mostly by the second Ig-like domain, which features an intermolecular {beta}-sheet formed by the joining of two individual GFC {beta}-sheets and a large but loosely packed hydrophobic cluster. Mutagenesis combined with gel filtration assays suggested that the side chain hydrogen bonds at the intermolecular {beta}-sheet are essential for the homophilic interaction and that the residues at the hydrophobic cluster play supplementary roles. Our structures reveal a conserved homophilic adhesion mode for the L1 family and also shed light on how the pathological mutations of L1 affect its structure and function.

  11. Homophilic adhesion mechanism of neurofascin, a member of the L1 family of neural cell adhesion molecules.

    PubMed

    Liu, Heli; Focia, Pamela J; He, Xiaolin

    2011-01-01

    The L1 family neural cell adhesion molecules play key roles in specifying the formation and remodeling of the neural network, but their homophilic interaction that mediates adhesion is not well understood. We report two crystal structures of a dimeric form of the headpiece of neurofascin, an L1 family member. The four N-terminal Ig-like domains of neurofascin form a horseshoe shape, akin to several other immunoglobulin superfamily cell adhesion molecules such as hemolin, axonin, and Dscam. The neurofascin dimer, captured in two crystal forms with independent packing patterns, reveals a pair of horseshoes in trans-synaptic adhesion mode. The adhesion interaction is mediated mostly by the second Ig-like domain, which features an intermolecular β-sheet formed by the joining of two individual GFC β-sheets and a large but loosely packed hydrophobic cluster. Mutagenesis combined with gel filtration assays suggested that the side chain hydrogen bonds at the intermolecular β-sheet are essential for the homophilic interaction and that the residues at the hydrophobic cluster play supplementary roles. Our structures reveal a conserved homophilic adhesion mode for the L1 family and also shed light on how the pathological mutations of L1 affect its structure and function. PMID:21047790

  12. Cytokine and adhesion molecule expression evolves between the neutrophilic and lymphocytic phases of viral meningitis.

    PubMed

    Makis, Alexandros; Shipway, David; Hatzimichael, Eleftheria; Galanakis, Emmanouil; Pshezhetskiy, Dmitry; Chaliasos, Nikolaos; Stebbing, Justin; Siamopoulou, Antigone

    2010-09-01

    Viral meningitis is characterized by cerebrospinal fluid (CSF) lymphocyte pleocytosis, although neutrophils may predominate in the early phase. The T helper 1 (Th1)/Th2 cytokine balance and expression of adhesion molecules seem to be involved in the CSF chemotaxis. We aimed to determine expression of cytokines and adhesion molecules in enteroviral meningitis. We investigated the serum and CSF levels of adhesion molecules (E-selectin, L-selectin, vascular cell adhesion molecule-1 [VCAM-1], and intracellular adhesion molecule-1 [ICAM-1]) and cytokines (interleukin-12 [IL-12] and IL-4) in 105 children during an outbreak of enteroviral meningitis. Diagnosis was confirmed with positive polymerase chain reaction (PCR) and/or serology for echovirus or Coxsackie virus, and matched with control subjects for clinical features but with negative PCR and/or serology. Apart from VCAM-1, the CSF levels of all investigated inflammatory molecules were significantly increased. In serum, sL-selectin and ICAM-1 levels were significantly higher than control subjects. Serum and CSF L-selectin, serum VCAM-1, and CSF IL-12 were all observed to be expressed in significantly higher levels in the neutrophil-dominant subgroup (72% had duration of symptoms <24 h) than in the lymphocyte-dominant group (87.5% had duration of symptoms >24 h). Serum and CSF ICAM-1 was found at significantly higher levels in the latter group. Evolving expression of adhesion molecules and cytokines indicates a shift from Th1 to Th2 immune responses as infection progresses.

  13. Modulation of lens cell adhesion molecules by particle beams

    NASA Technical Reports Server (NTRS)

    McNamara, M. P.; Bjornstad, K. A.; Chang, P. Y.; Chou, W.; Lockett, S. J.; Blakely, E. A.

    2001-01-01

    Cell adhesion molecules (CAMs) are proteins which anchor cells to each other and to the extracellular matrix (ECM), but whose functions also include signal transduction, differentiation, and apoptosis. We are testing a hypothesis that particle radiations modulate CAM expression and this contributes to radiation-induced lens opacification. We observed dose-dependent changes in the expression of beta 1-integrin and ICAM-1 in exponentially-growing and confluent cells of a differentiating human lens epithelial cell model after exposure to particle beams. Human lens epithelial (HLE) cells, less than 10 passages after their initial culture from fetal tissue, were grown on bovine corneal endothelial cell-derived ECM in medium containing 15% fetal bovine serum and supplemented with 5 ng/ml basic fibroblast growth factor (FGF-2). Multiple cell populations at three different stages of differentiation were prepared for experiment: cells in exponential growth, and cells at 5 and 10 days post-confluence. The differentiation status of cells was characterized morphologically by digital image analysis, and biochemically by Western blotting using lens epithelial and fiber cell-specific markers. Cultures were irradiated with single doses (4, 8 or 12 Gy) of 55 MeV protons and, along with unirradiated control samples, were fixed using -20 degrees C methanol at 6 hours after exposure. Replicate experiments and similar experiments with helium ions are in progress. The intracellular localization of beta 1-integrin and ICAM-1 was detected by immunofluorescence using monoclonal antibodies specific for each CAM. Cells known to express each CAM were also processed as positive controls. Both exponentially-growing and confluent, differentiating cells demonstrated a dramatic proton-dose-dependent modulation (upregulation for exponential cells, downregulation for confluent cells) and a change in the intracellular distribution of the beta 1-integrin, compared to unirradiated controls. In contrast

  14. Chinese Herbal Cardiotonic Pill Stabilizes Vulnerable Plaques in Rabbits by Decreasing the Expression of Adhesion Molecules

    PubMed Central

    Chen, Liang; Li, Xiaonan; Li, Changjiang; Rong, Yuanyuan; Xiao, Yawei; Xu, Xinsheng; Yao, Guihua; Jiang, Guihua

    2016-01-01

    Abstract: The cardiotonic pill (CP), consisting of a mixture of Radix Salviae Miltiorrhizae, Radix Notoginseng, and Borneolum Syntheticum, has been widely used in the prevention and treatment of cardiovascular disease. Adhesion molecules, including intercellular cell adhesion molecule-1 and vascular cell adhesion molecule-1, are involved in the development of vulnerable plaque. We investigated the effect of the CP in a rabbit model of vulnerable plaque established by local transfection with p53 gene. Compared with the control group, rabbits with vulnerable plaque showed a significantly lower intima-media thickness and plaque burden after CP treatment for 12 weeks. Moreover, the reduction in rate of plaque rupture and vulnerability index was similar. On enzyme-linked immunosorbent assay, real-time polymerase chain reaction, and immunohistochemistry analysis, the expression of intercellular cell adhesion molecule-1 and vascular cell adhesion molecule-1 was inhibited with CP treatment. CP treatment could postpone atherosclerotic plaque development and stabilize vulnerable plaque by inhibiting the expression of adhesion molecules in treatment of cardiovascular disease. PMID:27110743

  15. A new small molecule inhibitor of soluble guanylate cyclase

    PubMed Central

    Mota, Filipa; Gane, Paul; Hampden-Smith, Kathryn; Allerston, Charles K.; Garthwaite, John; Selwood, David L.

    2015-01-01

    Soluble guanylate cyclase (sGC) is a haem containing enzyme that regulates cardiovascular homeostasis and multiple mechanisms in the central and peripheral nervous system. Commonly used inhibitors of sGC activity act through oxidation of the haem moiety, however they also bind haemoglobin and this limits their bioavailability for in vivo studies. We have discovered a new class of small molecule inhibitors of sGC and have characterised a compound designated D12 (compound 10) which binds to the catalytic domain of the enzyme with a KD of 11 μM in a SPR assay. PMID:26264842

  16. En route from artificial to natural: Evaluation of inhibitors of mannose-specific adhesion of E. coli under flow.

    PubMed

    Möckl, Leonhard; Fessele, Claudia; Despras, Guillaume; Bräuchle, Christoph; Lindhorst, Thisbe K

    2016-09-01

    We investigated the properties of six Escherichia coli adhesion inhibitors under static and under flow conditions. On mannan-covered model substrates and under static conditions, all inhibitors were able to almost completely abolish lectin-mediated E. coli adhesion. On a monolayer of living human microvascular endothelial cells (HMEC-1), the inhibitors reduced adhesion under static conditions as well, but a large fraction of bacteria still managed to adhere even at highest inhibitor concentrations. In contrast, under flow conditions E. coli did not exhibit any adhesion to HMEC-1 not even at inhibitor concentrations where significant adhesion was detected under static conditions. This indicates that the presence of shear stress strongly affects inhibitor properties and must be taken into account when evaluating the potency of bacterial adhesion inhibitors.

  17. Synthetic Small-Molecule Prohormone Convertase 2 Inhibitors

    PubMed Central

    Kowalska, Dorota; Liu, Jin; Appel, Jon R.; Ozawa, Akihiko; Nefzi, Adel; Mackin, Robert B.; Houghten, Richard A.; Lindberg, Iris

    2009-01-01

    The proprotein convertases are believed to be responsible for the proteolytic maturation of a large number of peptide hormone precursors. Although potent furin inhibitors have been identified, thus far, no small-molecule prohormone convertase 1/3 or prohormone convertase 2 (PC2) inhibitors have been described. After screening 38 small-molecule positional scanning libraries against recombinant mouse PC2, two promising chemical scaffolds were identified: bicyclic guanidines, and pyrrolidine bis-piperazines. A set of individual compounds was designed from each library and tested against PC2. Pyrrolidine bis-piperazines were irreversible, time-dependent inhibitors of PC2, exhibiting noncompetitive inhibition kinetics; the most potent inhibitor exhibited a Ki value for PC2 of 0.54 μM. In contrast, the most potent bicyclic guanidine inhibitor exhibited a Ki value of 3.3 μM. Cross-reactivity with other convertases was limited: pyrrolidine bis-piperazines exhibited Ki values greater than 25 μM for PC1/3 or furin, whereas the Ki values of bicyclic guanidines for these other convertases were more than 15 μM. We conclude that pyrrolidine bis-piperazines and bicyclic guanidines represent promising initial leads for the optimization of therapeutically active PC2 inhibitors. PC2-specific inhibitors may be useful in the pharmacological blockade of PC2-dependent cleavage events, such as glucagon production in the pancreas and ectopic peptide production in small-cell carcinoma, and to study PC2-dependent proteolytic events, such as opioid peptide production. PMID:19074544

  18. Expression of Adhesion Molecules in Synovia of Patients with Treatment-Resistant Lyme Arthritis

    PubMed Central

    Akin, Evren; Aversa, John; Steere, Allen C.

    2001-01-01

    The expression of adhesion molecules in synovium in patients with Lyme arthritis is surely critical in the control of Borrelia burgdorferi infection but may also have pathologic consequences. For example, molecular mimicry between a dominant T-cell epitope of B. burgdorferi outer surface protein A and an adhesion molecule, human lymphocyte function-associated antigen 1 (LFA-1), has been implicated in the pathogenesis of treatment-resistant Lyme arthritis. Using immunohistochemical methods, we examined synovial samples for expression of adhesion molecules in 29 patients with treatment-resistant Lyme arthritis and in 15 patients with rheumatoid arthritis or chronic inflammatory monoarthritis. In Lyme arthritis synovia, endothelial cells showed intense expression of P-selectin and vascular adhesion protein-1 (VAP-1). Expression of LFA-1 was also intense on infiltrating cells, particularly in lymphoid aggregates, and intercellular adhesion molecule-1 (ICAM-1) was markedly expressed on synovial lining and endothelial and infiltrating cells. Moderate expression of vascular cell adhesion molecule-1 (VCAM-1) was seen on synovial lining and endothelial cells, and mild expression of its ligand, very late antigen-4, was apparent in perivascular lymphoid infiltrates. Except for lesser expression of VCAM-1 in Lyme synovia, the levels of expression of these adhesion molecules were similar in the three patient groups. We conclude that certain adhesion molecules, including ICAM-1 and LFA-1, are expressed intensely in the synovia of patients with Lyme arthritis. Upregulation of LFA-1 on lymphocytes in this lesion may be critical in the pathogenesis of treatment-resistant Lyme arthritis. PMID:11179355

  19. N-Glycosylation at the SynCAM (Synaptic Cell Adhesion Molecule) Immunoglobulin Interface Modulates Synaptic Adhesion

    SciTech Connect

    A Fogel; Y Li; Q Wang; T Lam; Y Modis; T Biederer

    2011-12-31

    Select adhesion molecules connect pre- and postsynaptic membranes and organize developing synapses. The regulation of these trans-synaptic interactions is an important neurobiological question. We have previously shown that the synaptic cell adhesion molecules (SynCAMs) 1 and 2 engage in homo- and heterophilic interactions and bridge the synaptic cleft to induce presynaptic terminals. Here, we demonstrate that site-specific N-glycosylation impacts the structure and function of adhesive SynCAM interactions. Through crystallographic analysis of SynCAM 2, we identified within the adhesive interface of its Ig1 domain an N-glycan on residue Asn(60). Structural modeling of the corresponding SynCAM 1 Ig1 domain indicates that its glycosylation sites Asn(70)/Asn(104) flank the binding interface of this domain. Mass spectrometric and mutational studies confirm and characterize the modification of these three sites. These site-specific N-glycans affect SynCAM adhesion yet act in a differential manner. Although glycosylation of SynCAM 2 at Asn(60) reduces adhesion, N-glycans at Asn(70)/Asn(104) of SynCAM 1 increase its interactions. The modification of SynCAM 1 with sialic acids contributes to the glycan-dependent strengthening of its binding. Functionally, N-glycosylation promotes the trans-synaptic interactions of SynCAM 1 and is required for synapse induction. These results demonstrate that N-glycosylation of SynCAM proteins differentially affects their binding interface and implicate post-translational modification as a mechanism to regulate trans-synaptic adhesion.

  20. Bead Aggregation Assays for the Characterization of Putative Cell Adhesion Molecules

    PubMed Central

    Emond, Michelle R.; Jontes, James D.

    2014-01-01

    Cell-cell adhesion is fundamental to multicellular life and is mediated by a diverse array of cell surface proteins. However, the adhesive interactions for many of these proteins are poorly understood. Here we present a simple, rapid method for characterizing the adhesive properties of putative homophilic cell adhesion molecules. Cultured HEK293 cells are transfected with DNA plasmid encoding a secreted, epitope-tagged ectodomain of a cell surface protein. Using functionalized beads specific for the epitope tag, the soluble, secreted fusion protein is captured from the culture medium. The coated beads can then be used directly in bead aggregation assays or in fluorescent bead sorting assays to test for homophilic adhesion. If desired, mutagenesis can then be used to elucidate the specific amino acids or domains required for adhesion. This assay requires only small amounts of expressed protein, does not require the production of stable cell lines, and can be accomplished in 4 days. PMID:25350770

  1. Small Molecule Inhibitors Targeting Activator Protein 1 (AP-1)

    PubMed Central

    2015-01-01

    Activator protein 1 (AP-1) is a pivotal transcription factor that regulates a wide range of cellular processes including proliferation, apoptosis, differentiation, survival, cell migration, and transformation. Accumulating evidence supports that AP-1 plays an important role in several severe disorders including cancer, fibrosis, and organ injury, as well as inflammatory disorders such as asthma, psoriasis, and rheumatoid arthritis. AP-1 has emerged as an actively pursued drug discovery target over the past decade. Excitingly, a selective AP-1 inhibitor T-5224 (51) has been investigated in phase II human clinical trials. Nevertheless, no effective AP-1 inhibitors have yet been approved for clinical use. Despite significant advances achieved in understanding AP-1 biology and function, as well as the identification of small molecules modulating AP-1 associated signaling pathways, medicinal chemistry efforts remain an urgent need to yield selective and efficacious AP-1 inhibitors as a viable therapeutic strategy for human diseases. PMID:24831826

  2. Effect of Chirality of Small Molecule Organofluorine Inhibitors of Amyloid Self-Assembly on Inhibitor Potency

    PubMed Central

    Sood, Abha; Abid, Mohammed; Hailemichael, Samson; Foster, Michelle; Török, Béla

    2009-01-01

    The effect of enantiomeric trifluromethyl-indolyl-acetic acid ethyl esters on the fibrillogenesis of Alzheimer's amyloid β (Aβ) peptide is described. These compounds have been previously identified as effective inhibitors of the Aβ self-assembly in their racemic form. Thioflavin-T Fluorescence Spectroscopy and Atomic Force Microscopy were applied to assess the potency of the chiral target compounds. Both enantiomers showed significant inhibition in the in vitro assays. The potency of the enantiomeric inhibitors appeared to be very similar to each other suggesting the lack of the stereospecific binding interactions between these small molecule inhibitors and the Aβ peptide. PMID:19880318

  3. Targeting Endothelial Adhesion Molecule Transcription for Treatment of Inflammatory Disease: A Proof-of-Concept Study

    PubMed Central

    Ashander, Liam M.; Appukuttan, Binoy; Ma, Yuefang; Gardner-Stephen, Dione; Smith, Justine R.

    2016-01-01

    Targeting the endothelial adhesion molecules that control leukocyte trafficking into a tissue has been explored as a biological therapy for inflammatory diseases. However, these molecules also participate in leukocyte migration for immune surveillance, and inhibiting the physiological level of an adhesion molecule might promote infection or malignancy. We explored the concept of targeting endothelial adhesion molecule transcription during inflammation in a human system. Intercellular adhesion molecule 1 (ICAM-1) mediates leukocyte migration across the retinal endothelium in noninfectious posterior uveitis. We observed an increase in the transcription factor, nuclear factor of kappa light polypeptide gene enhancer in B-cells 1 (NF-κB1), in parallel with ICAM-1, in human retinal endothelial cells treated with tumor necrosis factor-alpha (TNF-α), and identified putative binding sites for NF-κB1 within the ICAM-1 regulatory region. We targeted induced NF-κB1 expression in endothelial cells with small interfering (si)RNA. Knockdown of NF-κB1 significantly decreased cell surface expression of ICAM-1 protein induced by TNF-α but did not reduce constitutive ICAM-1 expression. Consistently, NF-κB1 knockdown significantly reduced leukocyte binding to cell monolayers in the presence of TNF-α but did not impact baseline binding. Findings of this proof-of-concept study indicate that induced transcription of endothelial adhesion molecules might be targeted therapeutically for inflammatory disease in humans. PMID:27293321

  4. Benzo[a]pyrene induces intercellular adhesion molecule-1 through a caveolae and aryl hydrocarbon receptor mediated pathway

    SciTech Connect

    Oesterling, Elizabeth; Toborek, Michal; Hennig, Bernhard

    2008-10-15

    Toxicologic and epidemiologic studies have linked benzo[a]pyrene (B[a]P) exposure with cardiovascular diseases such as atherosclerosis. The mechanisms of action leading to these diseases have not been fully understood. One key step in the development of atherosclerosis is vascular endothelial dysfunction, which is characterized by increased adhesiveness. To determine if B[a]P could lead to increased endothelial adhesiveness, the effects of B[a]P on human endothelial cell intercellular adhesion molecule-1 (ICAM-1) expression was investigated. B[a]P was able to increase ICAM-1 protein only after pretreatment with the aryl hydrocarbon receptor (AhR) agonist {beta}-naphthoflavone ({beta}-NF). Knockdown of AhR by siRNA or treatment with AhR antagonist {alpha}-naphthoflavone ({alpha}-NF) eliminated the induction of ICAM-1 from B[a]P, confirming the necessity of AhR in this process. Likewise, B[a]P only increased monocyte adhesion to the vascular endothelium when cells were pretreated with {beta}-NF. Experiments were done to define a signaling mechanism. B[a]P increased phosphorylation of MEK and p38-MAPK, and inhibitors to these proteins blunted the ICAM-1 induction. B[a]P was also able to increase AP-1 DNA binding and phosphorylation of cJun. Phosphorylation of cJun was disrupted by MEK and p38-MAPK inhibitors linking the signaling cascade. Finally, the importance of membrane microdomains, caveolae, was demonstrated by knockdown of the structural protein caveolin-1. Disruption of caveolae eliminated the B[a]P-induced ICAM-1 expression. These data suggest a possible pro-inflammatory mechanism of action of B[a]P involving caveolae, leading to increased vascular endothelial adhesiveness, and this inflammation may be a critical step in the development of B[a]P-induced atherosclerosis.

  5. [The expression level of adhesion molecules on neutrophils depending at segmentation of their nuclei].

    PubMed

    Kashutin, S L; Danilov, S I; Vereshchagina, E N; Kluchareva, S V

    2013-11-01

    The article deals with results of detection of expression level of adhesion molecules on neutrophils and segmentation of their nuclei. It is established that in conditions of absence of antigen stimulation neutrophils of circulating pool express molecules of L-selectin in 53.34%, LFA-1 molecules in 65.64%, ICAM-1 in 40.51%, LE4-3 in 58.72% and PECAM-1 in 59.74%. The full readiness to realization of phase of sliding, strong adhesion and immediately transmigration itselfis detected in neutrophils with five segments in nucleus.

  6. Small molecule glutaminase inhibitors block glutamate release from stimulated microglia.

    PubMed

    Thomas, Ajit G; O'Driscoll, Cliona M; Bressler, Joseph; Kaufmann, Walter; Rojas, Camilo J; Slusher, Barbara S

    2014-01-01

    Glutaminase plays a critical role in the generation of glutamate, a key excitatory neurotransmitter in the CNS. Excess glutamate release from activated macrophages and microglia correlates with upregulated glutaminase suggesting a pathogenic role for glutaminase. Both glutaminase siRNA and small molecule inhibitors have been shown to decrease excess glutamate and provide neuroprotection in multiple models of disease, including HIV-associated dementia (HAD), multiple sclerosis and ischemia. Consequently, inhibition of glutaminase could be of interest for treatment of these diseases. Bis-2-(5-phenylacetimido-1,2,4-thiadiazol-2-yl)ethyl sulfide (BPTES) and 6-diazo-5-oxo-l-norleucine (DON), two most commonly used glutaminase inhibitors, are either poorly soluble or non-specific. Recently, several new BPTES analogs with improved physicochemical properties were reported. To evaluate these new inhibitors, we established a cell-based microglial activation assay measuring glutamate release. Microglia-mediated glutamate levels were significantly augmented by tumor necrosis factor (TNF)-α, phorbol 12-myristate 13-acetate (PMA) and Toll-like receptor (TLR) ligands coincident with increased glutaminase activity. While several potent glutaminase inhibitors abrogated the increase in glutamate, a structurally related analog devoid of glutaminase activity was unable to block the increase. In the absence of glutamine, glutamate levels were significantly attenuated. These data suggest that the in vitro microglia assay may be a useful tool in developing glutaminase inhibitors of therapeutic interest. PMID:24269238

  7. Novel Small Molecule Entry Inhibitors of Ebola Virus

    PubMed Central

    Basu, Arnab; Mills, Debra M.; Mitchell, Daniel; Ndungo, Esther; Williams, John D.; Herbert, Andrew S.; Dye, John M.; Moir, Donald T.; Chandran, Kartik; Patterson, Jean L.; Rong, Lijun; Bowlin, Terry L.

    2015-01-01

    Background. The current Ebola virus (EBOV) outbreak has highlighted the troubling absence of available antivirals or vaccines to treat infected patients and stop the spread of EBOV. The EBOV glycoprotein (GP) plays critical roles in the early stage of virus infection, including receptor binding and membrane fusion, making it a potential target for the development of anti-EBOV drugs. We report the identification of 2 novel EBOV inhibitors targeting viral entry. Methods. To identify small molecule inhibitors of EBOV entry, we carried out a cell-based high-throughput screening using human immunodeficiency virus–based pseudotyped viruses expressing EBOV-GP. Two compounds were identified, and mechanism-of-action studies were performed using immunoflourescence, AlphaLISA, and enzymatic assays for cathepsin B inhibition. Results. We report the identification of 2 novel entry inhibitors. These inhibitors (1) inhibit EBOV infection (50% inhibitory concentration, approximately 0.28 and approximately 10 µmol/L) at a late stage of entry, (2) induce Niemann-Pick C phenotype, and (3) inhibit GP–Niemann-Pick C1 (NPC1) protein interaction. Conclusions. We have identified 2 novel EBOV inhibitors, MBX2254 and MBX2270, that can serve as starting points for the development of an anti-EBOV therapeutic agent. Our findings also highlight the importance of NPC1-GP interaction in EBOV entry and the attractiveness of NPC1 as an antifiloviral therapeutic target. PMID:26206510

  8. Adhesion molecules involved in hepoxilin A3-mediated neutrophil transepithelial migration

    PubMed Central

    Hurley, B P; Sin, A; McCormick, B A

    2008-01-01

    A common feature underlying active states of inflammation is the migration of neutrophils (PMNs) from the circulation and across a number of tissue barriers in response to chemoattractant stimuli. Although our group has recently established a discreet role for the PMN chemoattractant, hepoxilin A3 (HXA3) in the process of PMN recruitment, very little is known regarding the interaction of HXA3 with PMNs. To characterize further the event of HXA3-induced PMN transepithelial migration, we sought to determine the adhesion molecules required for migration across different epithelial surfaces (T84 intestinal and A549 airway cells) relative to two well-studied PMN chemoattractants, formyl-methionyl-leucyl-phenylalanine (fMLP) and leukotriene B4 (LTB4). Our findings reveal that the adhesion interaction profile of PMN transepithelial migration in response to HXA3 differs from the adhesion interaction profile exhibited by the structurally related eicosanoid LTB4. Furthermore, unique to PMN transepithelial migration induced by gradients of HXA3 was the critical dependency of all four major surface adhesion molecules examined (i.e. CD18, CD47, CD44 and CD55). Our results suggest that the particular chemoattractant gradient imposed, as well as the type of epithelial cell monolayer, each plays a role in determining the adhesion molecules involved in transepithelial migration. Given the complexities of these interactions, our findings are important to consider with respect to adhesion molecules that may be targeted for potential drug development. PMID:18005361

  9. RNA released from necrotic keratinocytes upregulates intercellular adhesion molecule-1 expression in melanocytes.

    PubMed

    Zhang, Shujie; Liu, Shuangchun; Yu, Ning; Xiang, Leihong

    2011-12-01

    Intercellular adhesion molecule-1 (ICAM-1) expression has been detected in melanocytes around active vitiligo patches as well as in surgically transplanted melanocytes. However, it is unclear whether and how skin injury induces the inappropriate expression of ICAM-1 and other proinflammatory genes in melanocytes. We previously reported that human melanocytes expressed TLR3. We hypothesized that the TLR3 expressed in melanocytes may recognize skin injury by binding to the endogenous ligands secreted by the damaged keratinocytes. Here we showed that RNA released from necrotic keratinocytes induced the upregulation of ICAM-1 protein and mRNA, as shown by FACS and real-time RT-PCR. Use of NF-κB inhibitor prevents upregulation of ICAM-1 in melanocytes indicating a direct role of NF-κB in necrotic keratinocyte-mediated upregulation of ICAM-1. Using a shRNA-expressing lentivirus, we demonstrated that in human melanocytes, TLR3 seems to be necessary for the upregulation of ICAM-1. Using oligonucleotide microarray, we demonstrated a dramatic increase in proinflammatory cytokine and chemokine transcripts (CXCL10, CXCL11, TNFSF10, CCL5, CCL4, CCL2, IFNB1, CCL20, IL-8, and CCL11). These observations suggested that RNA released from necrotic keratinocytes might act as an endogenous TLR3 ligand for the stimulation of ICAM-1 and other proinflammatory gene expression in human melanocytes, which might be involved in the pathogenesis of vitiligo following skin physical trauma.

  10. Myelin basic protein cleaves cell adhesion molecule L1 and promotes neuritogenesis and cell survival.

    PubMed

    Lutz, David; Loers, Gabriele; Kleene, Ralf; Oezen, Iris; Kataria, Hardeep; Katagihallimath, Nainesh; Braren, Ingke; Harauz, George; Schachner, Melitta

    2014-05-01

    The cell adhesion molecule L1 is a Lewis(x)-carrying glycoprotein that plays important roles in the developing and adult nervous system. Here we show that myelin basic protein (MBP) binds to L1 in a Lewis(x)-dependent manner. Furthermore, we demonstrate that MBP is released by murine cerebellar neurons as a sumoylated dynamin-containing protein upon L1 stimulation and that this MBP cleaves L1 as a serine protease in the L1 extracellular domain at Arg(687) yielding a transmembrane fragment that promotes neurite outgrowth and neuronal survival in cell culture. L1-induced neurite outgrowth and neuronal survival are reduced in MBP-deficient cerebellar neurons and in wild-type cerebellar neurons in the presence of an MBP antibody or L1 peptide containing the MBP cleavage site. Genetic ablation of MBP in shiverer mice and mutagenesis of the proteolytically active site in MBP or of the MBP cleavage site within L1 as well as serine protease inhibitors and an L1 peptide containing the MBP cleavage site abolish generation of the L1 fragment. Our findings provide evidence for novel functions of MBP in the nervous system. PMID:24671420

  11. Ciprofloxacin inhibits advanced glycation end products-induced adhesion molecule expression on human monocytes

    PubMed Central

    Mori, S; Takahashi, HK; Liu, K; Wake, H; Zhang, J; Liu, R; Yoshino, T; Nishibori, M

    2010-01-01

    BACKGROUND AND PURPOSE Advanced glycation end products (AGEs) subtypes, proteins or lipids that become glycated after exposure to sugars, can induce complications in diabetes. Among the various AGE subtypes, glyceraldehyde-derived AGE (AGE-2) and glycolaldehyde-derived AGE (AGE-3) are involved in inflammation in diabetic patients; monocytes are activated by these AGEs. Ciprofloxacin (CIP), a fluorinated 4-quinolone, is often used clinically to treat infections associated with diabetis due to its antibacterial properties. It also modulates immune responses in human peripheral blood mononuclear cells (PBMC) therefore we investigated the involvement of AGEs in these effects. EXPERIMENTAL APPROACH Expression of intercellular adhesion molecule (ICAM)-1, B7.1, B7.2 and CD40 was examined by flow cytometry. The production of tumour necrosis factor (TNF)-α, interferon (IFN)-γ, prostaglandin E2 (PGE2) and cAMP were determined by enzyme-linked immunosorbent assay. Cyclooxygenase (COX)-2 expression was determined by Western blot analysis. Lymphocyte proliferation was determined by [3H]-thymidine uptake. KEY RESULTS CIP induced PGE2 production in monocytes, irrespective of the presence of AGE-2 and AGE-3, by enhancing COX-2 expression; this led to an elevation of intracellular cAMP in monocytes. Non-selective and selective COX-2 inhibitors, indomethacin and NS398, inhibited CIP-induced PGE2 and cAMP production. In addition, CIP inhibited AGE-2- and AGE-3-induced expressions of ICAM-1, B7.1, B7.2 and CD40 in monocytes, the production of TNF-α and IFN-γ and lymphocyte proliferation in PBMC. Indomethacin, NS398 and a protein kinase A inhibitor, H89, inhibited the actions of CIP. CONCLUSIONS AND IMPLICATIONS CIP exerts immunomodulatory activity via PGE2, implying therapeutic potential of CIP for the treatment of AGE-2- and AGE-3-induced inflammatory responses. PMID:20718752

  12. Dihydromunduletone Is a Small-Molecule Selective Adhesion G Protein-Coupled Receptor Antagonist.

    PubMed

    Stoveken, Hannah M; Bahr, Laura L; Anders, M W; Wojtovich, Andrew P; Smrcka, Alan V; Tall, Gregory G

    2016-09-01

    Adhesion G protein-coupled receptors (aGPCRs) have emerging roles in development and tissue maintenance and is the most prevalent GPCR subclass mutated in human cancers, but to date, no drugs have been developed to target them in any disease. aGPCR extracellular domains contain a conserved subdomain that mediates self-cleavage proximal to the start of the 7-transmembrane domain (7TM). The two receptor protomers, extracellular domain and amino terminal fragment (NTF), and the 7TM or C-terminal fragment remain noncovalently bound at the plasma membrane in a low-activity state. We recently demonstrated that NTF dissociation liberates the 7TM N-terminal stalk, which acts as a tethered-peptide agonist permitting receptor-dependent heterotrimeric G protein activation. In many cases, natural aGPCR ligands are extracellular matrix proteins that dissociate the NTF to reveal the tethered agonist. Given the perceived difficulty in modifying extracellular matrix proteins to create aGPCR probes, we developed a serum response element (SRE)-luciferase-based screening approach to identify GPR56/ADGRG1 small-molecule inhibitors. A 2000-compound library comprising known drugs and natural products was screened for GPR56-dependent SRE activation inhibitors that did not inhibit constitutively active Gα13-dependent SRE activation. Dihydromunduletone (DHM), a rotenoid derivative, was validated using cell-free aGPCR/heterotrimeric G protein guanosine 5'-3-O-(thio)triphosphate binding reconstitution assays. DHM inhibited GPR56 and GPR114/ADGRG5, which have similar tethered agonists, but not the aGPCR GPR110/ADGRF1, M3 muscarinic acetylcholine, or β2 adrenergic GPCRs. DHM inhibited tethered peptide agonist-stimulated and synthetic peptide agonist-stimulated GPR56 but did not inhibit basal activity, demonstrating that it antagonizes the peptide agonist. DHM is a novel aGPCR antagonist and potentially useful chemical probe that may be developed as a future aGPCR therapeutic. PMID:27338081

  13. Lymphocyte subpopulations and the expression of intercellular adhesion molecules in chronic periodontitis.

    PubMed

    Cindrić, Gordan; Aurer, Andrej; Plancak, Darije; Ljerka, Jindra; Girotto, Miljena

    2004-12-01

    Immunological responses to invading bacteria play a major role in the course of inflammatory periodontal diseases, such as CP. It was suggested that one of the major elements in determining the course of the disease is the expression of cellular adhesion molecules. We therefore investigated the expression of cellular adhesion molecules, ICAM-1 and beta-1 integrins, capillary density and lymphocyte subpopulations in gingival biopsies obtained from 20 patients with CP who responded and 21 patient who failed to respond to initial treatment using immunohistochemical methods. We found no differences between the two groups in capillary density, ICAM-1 and beta-1 integrin expression. Patients who responded to treatment had a lymphocytic inflammatory infiltrate consisting predominantly of T cells, while those who failed to respond had an approximately equal number of T and B cells. Our findings support the role of host immunological mechanisms in determining the outcome of CP and argue against a major role of differential cellular adhesion molecule expression.

  14. Curcumin attenuates adhesion molecules and matrix metalloproteinase expression in hypercholesterolemic rabbits.

    PubMed

    Um, Min Young; Hwang, Kwang Hyun; Choi, Won Hee; Ahn, Jiyun; Jung, Chang Hwa; Ha, Tae Youl

    2014-10-01

    Curcumin, the yellow substance found in turmeric, possesses antioxidant, anti-inflammation, anticancer, and lipid-lowering properties. Because we hypothesized that curcumin could ameliorate the development of atherosclerosis, the present study focused on the effects and potential mechanisms of curcumin consumption on high-cholesterol diet-induced atherosclerosis in rabbits. During our study, New Zealand white rabbits were fed 1 of 3 experimental diets: a normal diet, a normal diet enriched with 1% cholesterol (HCD), or an HCD supplemented with 0.2% curcumin. At the end of 8 weeks, blood samples were collected to determine the levels of serum lipids, cytokines, and soluble adhesion molecule levels. Gene expression of adhesion molecules and matrix metalloproteinases (MMPs) in aortas were measured by quantitative real-time polymerase chain reaction and Western blot. Compared with the HCD group, rabbits fed an HCD supplemented with 0.2% curcumin had significantly less aortic lesion areas and neointima thickening. Curcumin reduced the levels of total cholesterol, triglyceride, low-density lipoprotein cholesterol, and oxidized low-density lipoprotein cholesterol in serum by 30.7%, 41.3%, 30.4%, and 66.9% (all P < .05), respectively, but did not affect high-density lipoprotein cholesterol levels. In addition, curcumin attenuated HCD-induced CD36 expression, circulating inflammatory cytokines, and soluble adhesive molecule levels. Curcumin reduced the mRNA and protein expression of intracellular adhesion molecule-1, vascular cell adhesion molecule-1, P-selectin, and monocyte chemotactic protein-1, and it inhibited HCD-induced up-regulation of MMP-1, MMP-2, and MMP-9. Our results demonstrate that curcumin exerts an antiatherosclerotic effect, which is mediated by multiple mechanisms that include lowering serum lipids and oxidized low-density lipoprotein, thus modulating the proinflammatory cytokine levels and altering adhesion molecules and MMP gene expression. PMID

  15. Curcumin attenuates adhesion molecules and matrix metalloproteinase expression in hypercholesterolemic rabbits.

    PubMed

    Um, Min Young; Hwang, Kwang Hyun; Choi, Won Hee; Ahn, Jiyun; Jung, Chang Hwa; Ha, Tae Youl

    2014-10-01

    Curcumin, the yellow substance found in turmeric, possesses antioxidant, anti-inflammation, anticancer, and lipid-lowering properties. Because we hypothesized that curcumin could ameliorate the development of atherosclerosis, the present study focused on the effects and potential mechanisms of curcumin consumption on high-cholesterol diet-induced atherosclerosis in rabbits. During our study, New Zealand white rabbits were fed 1 of 3 experimental diets: a normal diet, a normal diet enriched with 1% cholesterol (HCD), or an HCD supplemented with 0.2% curcumin. At the end of 8 weeks, blood samples were collected to determine the levels of serum lipids, cytokines, and soluble adhesion molecule levels. Gene expression of adhesion molecules and matrix metalloproteinases (MMPs) in aortas were measured by quantitative real-time polymerase chain reaction and Western blot. Compared with the HCD group, rabbits fed an HCD supplemented with 0.2% curcumin had significantly less aortic lesion areas and neointima thickening. Curcumin reduced the levels of total cholesterol, triglyceride, low-density lipoprotein cholesterol, and oxidized low-density lipoprotein cholesterol in serum by 30.7%, 41.3%, 30.4%, and 66.9% (all P < .05), respectively, but did not affect high-density lipoprotein cholesterol levels. In addition, curcumin attenuated HCD-induced CD36 expression, circulating inflammatory cytokines, and soluble adhesive molecule levels. Curcumin reduced the mRNA and protein expression of intracellular adhesion molecule-1, vascular cell adhesion molecule-1, P-selectin, and monocyte chemotactic protein-1, and it inhibited HCD-induced up-regulation of MMP-1, MMP-2, and MMP-9. Our results demonstrate that curcumin exerts an antiatherosclerotic effect, which is mediated by multiple mechanisms that include lowering serum lipids and oxidized low-density lipoprotein, thus modulating the proinflammatory cytokine levels and altering adhesion molecules and MMP gene expression.

  16. Glossogyne tenuifolia Extract Inhibits TNF-α-Induced Expression of Adhesion Molecules in Human Umbilical Vein Endothelial Cells via Blocking the NF-kB Signaling Pathway.

    PubMed

    Hsuan, Chin-Feng; Hsu, Hsia-Fen; Tseng, Wei-Kung; Lee, Thung-Lip; Wei, Yu-Feng; Hsu, Kwan-Lih; Wu, Chau-Chung; Houng, Jer-Yiing

    2015-09-17

    Chronic inflammation plays a pivotal role in the development of atherosclerosis, where the pro-inflammatory cytokine-induced expression of endothelial adhesion molecules and the recruitment of monocytes are the crucial events leading to its pathogenesis. Glossogyne tenuifolia ethanol extract (GTE) is shown to have potent anti-inflammatory and antioxidant activities. We evaluated the effects of GTE and its major components, luteolin (lut), luteolin-7-glucoside (lut-7-g), and oleanolic acid (OA) on TNF-α-induced expression of adhesion molecules in human umbilical vein endothelial cells (HUVECs). The results demonstrated that GTE, lut, and lut-7-g attenuated the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in TNF-α-activated HUVECs, and inhibited the adhesion of monocytes to TNF-α-activated HUVECs. The TNF-α-induced mRNA expression of ICAM-1 and VCAM-1 was also suppressed, revealing their inhibitory effects at the transcriptional level. Furthermore, GTE, lut, and lut-7-g blocked the TNF-α-induced degradation of nuclear factor-kB inhibitor (IkB), an indicator of the activation of nuclear factor-kB (NF-kB). In summary, GTE and its bioactive components were effective in preventing the adhesion of monocytes to cytokine-activated endothelium by the inhibition of expression of adhesion molecules, which in turn is mediated through blocking the activation and nuclear translocation of NF-kB. The current results reveal the therapeutic potential of GTE in atherosclerosis.

  17. Glossogyne tenuifolia Extract Inhibits TNF-α-Induced Expression of Adhesion Molecules in Human Umbilical Vein Endothelial Cells via Blocking the NF-kB Signaling Pathway.

    PubMed

    Hsuan, Chin-Feng; Hsu, Hsia-Fen; Tseng, Wei-Kung; Lee, Thung-Lip; Wei, Yu-Feng; Hsu, Kwan-Lih; Wu, Chau-Chung; Houng, Jer-Yiing

    2015-01-01

    Chronic inflammation plays a pivotal role in the development of atherosclerosis, where the pro-inflammatory cytokine-induced expression of endothelial adhesion molecules and the recruitment of monocytes are the crucial events leading to its pathogenesis. Glossogyne tenuifolia ethanol extract (GTE) is shown to have potent anti-inflammatory and antioxidant activities. We evaluated the effects of GTE and its major components, luteolin (lut), luteolin-7-glucoside (lut-7-g), and oleanolic acid (OA) on TNF-α-induced expression of adhesion molecules in human umbilical vein endothelial cells (HUVECs). The results demonstrated that GTE, lut, and lut-7-g attenuated the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in TNF-α-activated HUVECs, and inhibited the adhesion of monocytes to TNF-α-activated HUVECs. The TNF-α-induced mRNA expression of ICAM-1 and VCAM-1 was also suppressed, revealing their inhibitory effects at the transcriptional level. Furthermore, GTE, lut, and lut-7-g blocked the TNF-α-induced degradation of nuclear factor-kB inhibitor (IkB), an indicator of the activation of nuclear factor-kB (NF-kB). In summary, GTE and its bioactive components were effective in preventing the adhesion of monocytes to cytokine-activated endothelium by the inhibition of expression of adhesion molecules, which in turn is mediated through blocking the activation and nuclear translocation of NF-kB. The current results reveal the therapeutic potential of GTE in atherosclerosis. PMID:26393541

  18. Molecular Architecture of a Complex between an Adhesion Protein from the Malaria Parasite and Intracellular Adhesion Molecule 1*

    PubMed Central

    Brown, Alan; Turner, Louise; Christoffersen, Stig; Andrews, Katrina A.; Szestak, Tadge; Zhao, Yuguang; Larsen, Sine; Craig, Alister G.; Higgins, Matthew K.

    2013-01-01

    The adhesion of Plasmodium falciparum-infected erythrocytes to human tissues or endothelium is central to the pathology caused by the parasite during malaria. It contributes to the avoidance of parasite clearance by the spleen and to the specific pathologies of cerebral and placental malaria. The PfEMP1 family of adhesive proteins is responsible for this sequestration by mediating interactions with diverse human ligands. In addition, as the primary targets of acquired, protective immunity, the PfEMP1s are potential vaccine candidates. PfEMP1s contain large extracellular ectodomains made from CIDR (cysteine-rich interdomain regions) and DBL (Duffy-binding-like) domains and show extensive variation in sequence, size, and domain organization. Here we use biophysical methods to characterize the entire ∼300-kDa ectodomain from IT4VAR13, a protein that interacts with the host receptor, intercellular adhesion molecule-1 (ICAM-1). We show through small angle x-ray scattering that IT4VAR13 is rigid, elongated, and monomeric. We also show that it interacts with ICAM-1 through the DBLβ domain alone, forming a 1:1 complex. These studies provide a first low resolution structural view of a PfEMP1 ectodomain in complex with its ligand. They show that it combines a modular domain arrangement consisting of individual ligand binding domains, with a defined higher order architecture that exposes the ICAM-1 binding surface to allow adhesion. PMID:23297413

  19. Wnt/beta-Catenin Signaling and Small Molecule Inhibitors

    PubMed Central

    Voronkov, Andrey; Krauss, Stefan

    2012-01-01

    Wnt/β-catenin signaling is a branch of a functional network that dates back to the first metazoans and it is involved in a broad range of biological systems including stem cells, embryonic development and adult organs. Deregulation of components involved in Wnt/β-catenin signaling has been implicated in a wide spectrum of diseases including a number of cancers and degenerative diseases. The key mediator of Wnt signaling, β-catenin, serves several cellular functions. It functions in a dynamic mode at multiple cellular locations, including the plasma membrane, where β-catenin contributes to the stabilization of intercellular adhesive complexes, the cytoplasm where β-catenin levels are regulated and the nucleus where β-catenin is involved in transcriptional regulation and chromatin interactions. Central effectors of β-catenin levels are a family of cysteine-rich secreted glycoproteins, known as Wnt morphogens. Through the LRP5/6-Frizzled receptor complex, Wnts regulate the location and activity of the destruction complex and consequently intracellular β- catenin levels. However, β-catenin levels and their effects on transcriptional programs are also influenced by multiple other factors including hypoxia, inflammation, hepatocyte growth factor-mediated signaling, and the cell adhesion molecule E-cadherin. The broad implications of Wnt/β-catenin signaling in development, in the adult body and in disease render the pathway a prime target for pharmacological research and development. The intricate regulation of β-catenin at its various locations provides alternative points for therapeutic interventions. PMID:23016862

  20. Wheat proteins enhance stability and function of adhesion molecules in cryopreserved hepatocytes.

    PubMed

    Grondin, Mélanie; Hamel, Francine; Averill-Bates, Diana A; Sarhan, Fathey

    2009-01-01

    Cryopreserved hepatocytes with good hepatospecific functions upon thawing are important for clinical transplantation and for in vitro drug toxicity testing. However, cryopreservation reduces viability and certain hepatospecific functions, but the most pronounced change is diminished attachment efficiency of hepatocytes. Adhesion of cells to the extracellular matrix and cell-cell contacts are crucial for many aspects of cellular function. These processes are partly mediated and controlled by cellular adhesion molecules. The mechanisms responsible for reduced attachment efficiency of cryopreserved hepatocytes are not well understood. To address this question, we investigated the effect of a new cryopreservation procedure, using wheat proteins (WPs) or mixtures of recombinant forms of wheat freezing tolerance-associated proteins, on the stability of three important adhesion molecules (beta1-integrin, E-cadherin, and beta-catenin). Immunoblot analyses revealed that the levels of beta1-integrin, E-cadherin, and beta-catenin were much lower in cryopreserved rat hepatocytes, when compared to fresh cells. Protein expression of the adhesion molecules was generally lower in cells cryopreserved with DMSO, compared to WPs. Moreover, the stability of the adhesion molecules was not affected by cryopreservation to the same degree, with more pronounced decreases occurring for beta1-integrin (62-74%) > beta-catenin (51-58%) > E-cadherin (21-37%). However, when hepatocytes were cryopreserved with partially purified WPs (SulWPE, AcWPE) or with mixtures of recombinant wheat proteins, there was a clear protective effect against the loss of protein expression of beta1-integrin, E-cadherin, and beta-catenin. Protein expression was only 10-20% lower than that observed in fresh hepatocytes. These findings clearly demonstrate that WPs, and more particularly, partially purified WPs and recombinant wheat proteins, were more efficient for cryopreservation of rat hepatocytes by maintaining good

  1. Unique small molecule entry inhibitors of hemorrhagic fever arenaviruses.

    PubMed

    Lee, Andrew M; Rojek, Jillian M; Spiropoulou, Christina F; Gundersen, Anette T; Jin, Wei; Shaginian, Alex; York, Joanne; Nunberg, Jack H; Boger, Dale L; Oldstone, Michael B A; Kunz, Stefan

    2008-07-01

    Viral hemorrhagic fevers caused by the arenaviruses Lassa virus in Africa and Machupo, Guanarito, Junin, and Sabia virus in South America are among the most devastating emerging human diseases with fatality rates of 15-35% and a limited antiviral therapeutic repertoire available. Here we used high throughput screening of synthetic combinatorial small molecule libraries to identify inhibitors of arenavirus infection using pseudotyped virion particles bearing the glycoproteins (GPs) of highly pathogenic arenaviruses. Our screening efforts resulted in the discovery of a series of novel small molecule inhibitors of viral entry that are highly active against both Old World and New World hemorrhagic arenaviruses. We observed potent inhibition of infection of human and primate cells with live hemorrhagic arenaviruses (IC(50)=500-800 nm). Investigations of the mechanism of action revealed that the candidate compounds efficiently block pH-dependent fusion by the arenavirus GPs (IC(50) of 200-350 nm). Although our lead compounds were potent against phylogenetically distant arenaviruses, they did not show activity against other enveloped viruses with class I viral fusion proteins, indicating specificity for arenavirus GP-mediated membrane fusion.

  2. Novel pyridazinone inhibitors for vascular adhesion protein-1 (VAP-1): old target-new inhibition mode.

    PubMed

    Bligt-Lindén, Eva; Pihlavisto, Marjo; Szatmári, István; Otwinowski, Zbyszek; Smith, David J; Lázár, László; Fülöp, Ferenc; Salminen, Tiina A

    2013-12-27

    Vascular adhesion protein-1 (VAP-1) is a primary amine oxidase and a drug target for inflammatory and vascular diseases. Despite extensive attempts to develop potent, specific, and reversible inhibitors of its enzyme activity, the task has proven challenging. Here we report the synthesis, inhibitory activity, and molecular binding mode of novel pyridazinone inhibitors, which show specificity for VAP-1 over monoamine and diamine oxidases. The crystal structures of three inhibitor-VAP-1 complexes show that these compounds bind reversibly into a unique binding site in the active site channel. Although they are good inhibitors of human VAP-1, they do not inhibit rodent VAP-1 well. To investigate this further, we used homology modeling and structural comparison to identify amino acid differences, which explain the species-specific binding properties. Our results prove the potency and specificity of these new inhibitors, and the detailed characterization of their binding mode is of importance for further development of VAP-1 inhibitors.

  3. 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.

  4. NADPH oxidase and lipid raft-associated redox signaling are required for PCB153-induced upregulation of cell adhesion molecules in human brain endothelial cells

    SciTech Connect

    Eum, Sung Yong Andras, Ibolya; Hennig, Bernhard; Toborek, Michal

    2009-10-15

    Exposure to persistent organic pollutants, such as polychlorinated biphenyls (PCBs), can lead to chronic inflammation and the development of vascular diseases. Because cell adhesion molecules (CAMs) of the cerebrovascular endothelium regulate infiltration of inflammatory cells into the brain, we have explored the molecular mechanisms by which ortho-substituted polychlorinated biphenyls (PCBs), such as PCB153, can upregulate CAMs in brain endothelial cells. Exposure to PCB153 increased expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), as well as elevated adhesion of leukocytes to brain endothelial cells. These effects were impeded by inhibitors of EGFR, JAKs, or Src activity. In addition, pharmacological inhibition of NADPH oxidase or disruption of lipid rafts by cholesterol depleting agents blocked PCB153-induced phosphorylation of JAK and Src kinases and upregulation of CAMs. In contrast, silencing of caveolin-1 by siRNA interference did not affect upregulation of ICAM-1 and VCAM-1 in brain endothelial cells stimulated by PCB153. Results of the present study indicate that lipid raft-dependent NADPH oxidase/JAK/EGFR signaling mechanisms regulate the expression of CAMs in brain endothelial cells and adhesion of leukocytes to endothelial monolayers. Due to its role in leukocyte infiltration, induction of CAMs may contribute to PCB-induced cerebrovascular disorders and neurotoxic effects in the CNS.

  5. Adhesion molecules in peritoneal dissemination: function, prognostic relevance and therapeutic options.

    PubMed

    Sluiter, Nina; de Cuba, Erienne; Kwakman, Riom; Kazemier, Geert; Meijer, Gerrit; Te Velde, Elisabeth Atie

    2016-06-01

    Peritoneal dissemination is diagnosed in 10-25 % of colorectal cancer patients. Selected patients are treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. For these patients, earlier diagnosis, optimised selection criteria and a personalised approach are warranted. Biomarkers could play a crucial role here. However, little is known about possible candidates. Considering tumour cell adhesion as a key step in peritoneal dissemination, we aim to provide an overview of the functional importance of adhesion molecules in peritoneal dissemination and discuss the prognostic, diagnostic and therapeutic options of these candidate biomarkers. A systematic literature search was conducted according to the PRISMA guidelines. In 132 in vitro, ex vivo and in vivo studies published between 1995 and 2013, we identified twelve possibly relevant adhesion molecules in various cancers that disseminate peritoneally. The most studied molecules in tumour cell adhesion are integrin α2β1, CD44 s and MUC16. Furthermore, L1CAM, EpCAM, MUC1, sLe(x) and Le(x), chemokine receptors, Betaig-H3 and uPAR might be of clinical importance. ICAM1 was found to be less relevant in tumour cell adhesion in the context of peritoneal metastases. Based on currently available data, sLe(a) and MUC16 are the most promising prognostic biomarkers for colorectal peritoneal metastases that may help improve patient selection. Different adhesion molecules appear expressed in haematogenous and transcoelomic spread, indicating two different attachment processes. However, our extensive assessment of available literature reveals that knowledge on metastasis-specific genes and their possible candidates is far from complete. PMID:27074785

  6. Coupling factor 6 downregulates platelet endothelial cell adhesion molecule-1 via c-Src activation and acts as a proatherogenic molecule.

    PubMed

    Kumagai, Akiko; Osanai, Tomohiro; Katoh, Chisato; Tanaka, Makoto; Tomita, Hirofumi; Morimoto, Takeshi; Murakami, Reiichi; Magota, Koji; Okumura, Ken

    2008-09-01

    Coupling factor 6 (CF6), a component of ATP synthase, suppresses the generation of prostacyclin and nitric oxide (NO). Platelet endothelial cell adhesion molecule-1 (PECAM-1) is involved in shear-induced NO production. To investigate the linkage between the actions of CF6 and PECAM-1, we examined the effects of CF6 on PECAM-1 expression and shear-mediated NO release, comparatively with those of angiotensin II (AngII). Treatment of human umbilical vein endothelial cells (HUVEC) and aortic endothelial cells (HAEC) with CF6 at 10(-7)M or AngII at 10(-7)M for 24h suppressed PECAM-1 gene and protein expression. CF6 or AngII activated c-Src at 15 min in HUVEC, and blockade of c-Src with PP1, its specific inhibitor, restored them. Efrapeptin, an inhibitor of ATPase, attenuated CF6-induced suppression of PECAM-1 gene expression by blockade of acidification, whereas superoxide dismutase or apocinin, an inhibitor of NADPH oxidase, blocked AngII-induced suppression of PECAM-1. Exposure of the cells to shear stress at 25 dynes/cm(2) for 30 min enhanced phosphorylation of eNOS at Ser(1177) and NO release. Pretreatment with CF6 or AngII for 24h attenuated them in HUVEC and HAEC. These suggest that CF6 downregulates PECAM-1 expression via c-Src activation and attenuates shear-induced NO release presumably by suppressing eNOS phosphorylation. PMID:18243211

  7. Choice of anesthetic technique on plasma concentrations of interleukins and cell adhesion molecules

    PubMed Central

    2013-01-01

    Background Whether inflammatory responses to surgery are comparably activated during total intravenous anesthesia (TIVA) and during volatile anesthesia remains unclear. We thus compared the perioperative effects of TIVA and isoflurane anesthesia on plasma concentrations of proinflammatory and anti-inflammatory interleukins and cell adhesion molecules. Methods Patients having laparoscopic cholecystectomies were randomly allocated to two groups: 44 were assigned to TIVA and 44 to isoflurane anesthesia. IL-1β, IL-6, IL-8, IL-10, IL-13, and the cellular adhesion molecules intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 were determined preoperatively, before incision, and at 2 and 24 hours postoperatively. Our primary outcomes were area-under-the-curve cytokine and adhesion molecule concentrations over 24 postoperative hours. Results The only statistically significant difference in area-under-the-curve concentrations was for IL-6, which was greater in patients given isoflurane:78 (95% confidence interval (CI): 52 to 109) pg/ml versus 33 (22 to 50) pg/ml, P= 0.006. Two hours after surgery, IL-6 was significantly greater than baseline in patients assigned to isoflurane: 47 (95% CI: 4 to 216, P<0.001) pg/ml versus 18 (95%CI: 4 to 374, P<0.001) pg/ml in the TIVA group. In contrast, IL-10 was significantly greater in patients assigned to TIVA: 20 (95% CI: 2 to 140, P<0.001) pg/ml versus 12 (95% CI: 3 to 126, P<0.001) pg/ml. By 24 hours after surgery, concentrations were generally similar between study groups and similar to baseline values. Conclusion The only biomarker whose postoperative area-under-the-curve concentrations differed significantly as a function of anesthetic management was IL-6. Two hours after surgery, IL-6 concentrations were significantly greater in patients given isoflurane than TIVA. However, the differences were modest and seem unlikely to prove clinically important. Further studies are needed. PMID:24472144

  8. Cyclic AMP pathway modifies memory through neural cell adhesion molecule alterations in the rat hippocampus.

    PubMed

    Razmi, Ali; Sahebgharani, Mousa; Khani, Mohammad Hossein; Paylakhi, Seyed Hassan; Faizi, Mehrdad; Zarrindast, Mohammad-Reza

    2014-01-01

    Neural Cell Adhesion Molecules (NCAMs) are known to influence memory by affecting neural cell-cell and cell-extracellular matrix junctions. This study investigated the possible role of cAMP pathway in the expression of hippocampal NCAM and its polysialylated derivative (PSA-NCAM). The following pharmacological tools were employed for manipulation of cAMP pathway: a) forskolin; the activator of adenylyl cyclase (AC), b) 8-Br-cAMP; a protein kinase A (PKA) agonist, c) 8-pCPT-2'-O-Me-cAMP; a selective enhancer of exchange protein activated by cAMP (Epac) and d) Rp-cAMP; a PKA inhibitor. Memory acquisition was tested by passive avoidance paradigm after injecting the above compounds for three consecutive days into the CA1 region of dorsal hippocampus of rats. Forskolin and 8-Br-cAMP enhanced memory retrieval while Rp-cAMP significantly reduced memory and NCAM levels. 8-pCPT-2'-O-Me-cAMP failed to alter memory performance or NCAM levels as compared to vehicle. We observed no significant changes in PSA-NCAM, however the expression of St8sia4 and St8sia2 (the polysialyltransferase isoforms) were altered. The mRNA levels of St8sia4 was down-regulated by 8-Br-cAMP, Rp-cAMP and 8-pCPT while forskolin led to almost 3 and 5 fold increase in mRNAs of St8sia2 and St8sia4, respectively. The current insight might endorse the predominant role of PKA as compared to Epac in cAMP pathway in expression of NCAM and memory function. PMID:24901853

  9. 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

  10. Spatio-Temporally Restricted Expression of Cell Adhesion Molecules during Chicken Embryonic Development

    PubMed Central

    Roy, Priti; Bandyopadhyay, Amitabha

    2014-01-01

    Differential cell adhesive properties are known to regulate important developmental events like cell sorting and cell migration. Cadherins and protocadherins are known to mediate these cellular properties. Though a large number of such molecules have been predicted, their characterization in terms of interactive properties and cellular roles is far from being comprehensive. To narrow down the tissue context and collect correlative evidence for tissue specific roles of these molecules, we have carried out whole-mount in situ hybridization based RNA expression study for seven cadherins and four protocadherins. In developing chicken embryos (HH stages 18, 22, 26 and 28) cadherins and protocadherins are expressed in tissue restricted manner. This expression study elucidates precise expression domains of cell adhesion molecules in the context of developing embryos. These expression domains provide spatio-temporal context in which the function of these genes can be further explored. PMID:24806091

  11. Single-molecule enzyme kinetics in the presence of inhibitors.

    PubMed

    Saha, Soma; Sinha, Antara; Dua, Arti

    2012-07-28

    Recent studies in single-molecule enzyme kinetics reveal that the turnover statistics of a single enzyme is governed by the waiting time distribution that decays as mono-exponential at low substrate concentration and multi-exponential at high substrate concentration. The multi-exponentiality arises due to protein conformational fluctuations, which act on the time scale longer than or comparable to the catalytic reaction step, thereby inducing temporal fluctuations in the catalytic rate resulting in dynamic disorder. In this work, we study the turnover statistics of a single enzyme in the presence of inhibitors to show that the multi-exponentiality in the waiting time distribution can arise even when protein conformational fluctuations do not influence the catalytic rate. From the Michaelis-Menten mechanism of inhibited enzymes, we derive exact expressions for the waiting time distribution for competitive, uncompetitive, and mixed inhibitions to quantitatively show that the presence of inhibitors can induce dynamic disorder in all three modes of inhibitions resulting in temporal fluctuations in the reaction rate. In the presence of inhibitors, dynamic disorder arises due to transitions between active and inhibited states of enzymes, which occur on time scale longer than or comparable to the catalytic step. In this limit, the randomness parameter (dimensionless variance) is greater than unity indicating the presence of dynamic disorder in all three modes of inhibitions. In the opposite limit, when the time scale of the catalytic step is longer than the time scale of transitions between active and inhibited enzymatic states, the randomness parameter is unity, implying no dynamic disorder in the reaction pathway.

  12. Elevated vascular cell adhesion molecule-1 in AIDS encephalitis induced by simian immunodeficiency virus.

    PubMed Central

    Sasseville, V. G.; Newman, W. A.; Lackner, A. A.; Smith, M. O.; Lausen, N. C.; Beall, D.; Ringler, D. J.

    1992-01-01

    AIDS encephalitis is a common sequela to HIV-1 infection in humans and simian immunodeficiency virus (SIVmac) infection in macaques. Although lentiviral-infected macrophages comprise parenchymal inflammatory infiltrates in affected brain tissue, the mechanisms responsible for leukocyte trafficking to the central nervous system in AIDS are unknown. In this study, we investigated the expression of various endothelial-derived leukocyte adhesion proteins in SIVmac-induced AIDS encephalitis. Encephalitic brains from SIVmac-infected macaques, but not uninflamed brains from other SIVmac-infected animals, were found to express abundant vascular cell adhesion molecule-1 (VCAM-1) protein on the majority of arteriolar, venular, and capillary endothelial cells. Soluble VCAM-1 concentrations in cerebrospinal fluid (CSF) from encephalitic animals were increased approximately 20-fold above those from animals without AIDS encephalitis. Expression of other endothelial-related adhesion molecules, including E-selectin, P-selectin, and intercellular adhesion molecule-1 (ICAM-1), was not uniformly associated with AIDS encephalitis. Thus, the presence of VCAM-1 in both brain and CSF was uniformly associated with SIVmac-induced disease of the central nervous system, and this expression may, at least in part, influence monocyte and lymphocyte recruitment to the central nervous system during the development of AIDS encephalitis. Moreover, measurement of soluble VCAM-1 in CSF may assist in the clinical assessment of animals or people with AIDS. Images Figure 1 PMID:1279978

  13. HEMCAM, an adhesion molecule expressed by c-kit+ hemopoietic progenitors

    PubMed Central

    1996-01-01

    We have characterized the adhesion molecule HEMCAM, which is expressed by hemopoietic progenitors of embryonic bone marrow. HEMCAM belongs to the immunoglobulin superfamily and consists of the V-V-C2-C2-C2 Ig domains. There are three mRNA splice variants. One has a short cytoplasmic tail; another has a long tail; while the third seems to lack transmembrane and cytoplasmic regions. Except for the NH2-terminal sequence, HEMCAM is identical to gicerin, a molecular involved in neurite outgrowth and Wilm's kidney tumor progression in the chicken and it is significantly homologous with MUC18 a molecule involved in melanoma progression and metastasis in human beings. In the bone marrow the HEMCAM+ cell population contains c-kit+ subsets. HEMCAM+ cells coexpressing the receptor tyrosine kinase c-kit give rise to T cells at a frequency of 0.17 when injected intrathymically in congenic animals. As HEMCAM+, c-kit+ cells differentiate into myeloid and erythroid CFU's the double-positive cell population seems to contain precursors for multiple lineages. HEMCAM promotes cell-cell adhesion of transfected cells. Cross-linking of murine HEMCAM leads to cell spreading of T- lymphocyte progenitors adhering to the vascular adhesion molecules, PECAM-1 and VCAM-1. Thus, HEMCAM is likely to be involved in cellular adhesion and homing processes. PMID:8978830

  14. TNF-α enhances vascular cell adhesion molecule-1 expression in human bone marrow mesenchymal stem cells via the NF-κB, ERK and JNK signaling pathways

    PubMed Central

    LU, ZI-YUAN; CHEN, WAN-CHENG; LI, YONG-HUA; LI, LI; ZHANG, HANG; PANG, YAN; XIAO, ZHI-FANG; XIAO, HAO-WEN; XIAO, YANG

    2016-01-01

    The migration of circulating mesenchymal stem cells (MSCs) to injured tissue is an important step in tissue regeneration and requires adhesion to the microvascular endothelium. The current study investigated the underlying mechanism of MSC adhesion to endothelial cells during inflammation. In in vitro MSC culture, tumor necrosis factor-α (TNF-α) increased the level of vascular cell adhesion molecule-1 (VCAM-1) expression in a dose-dependent manner. The nuclear factor-κB (NF-κB), extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) signaling pathway inhibitors, pyrrolidine dithiocarbamate (PDTC), U0126 and SP600125, respectively, suppressed VCAM-1 expression induced by TNF-α at the mRNA and protein levels (P<0.05). TNF-α augmented the activation of NF-κB, ERK and JNK, and promoted MSC adhesion to human umbilical vein endothelial cells; however, the inhibitors of NF-κB, ERK and JNK did not affect this process in these cells. The results of the current study indicate that adhesion of circulating MSCs to the endothelium is regulated by TNF-α-induced VCAM-1 expression, which is potentially mediated by the NF-κB, ERK and JNK signaling pathways. PMID:27221006

  15. Therapeutic potential of an orally effective small molecule inhibitor of plasminogen activator inhibitor for asthma.

    PubMed

    Liu, Rui-Ming; Eldridge, Stephanie; Watanabe, Nobuo; Deshane, Jessy; Kuo, Hui-Chien; Jiang, Chunsun; Wang, Yong; Liu, Gang; Schwiebert, Lisa; Miyata, Toshio; Thannickal, Victor J

    2016-02-15

    Asthma is one of the most common respiratory diseases. Although progress has been made in our understanding of airway pathology and many drugs are available to relieve asthma symptoms, there is no cure for chronic asthma. Plasminogen activator inhibitor 1 (PAI-1), a primary inhibitor of tissue-type and urokinase-type plasminogen activators, has pleiotropic functions besides suppression of fibrinolysis. In this study, we show that administration of TM5275, an orally effective small-molecule PAI-1 inhibitor, 25 days after ovalbumin (OVA) sensitization-challenge, significantly ameliorated airway hyperresponsiveness in an OVA-induced chronic asthma model. Furthermore, we show that TM5275 administration significantly attenuated OVA-induced infiltration of inflammatory cells (neutrophils, eosinophils, and monocytes), the increase in the levels of OVA-specific IgE and Th2 cytokines (IL-4 and IL-5), the production of mucin in the airways, and airway subepithelial fibrosis. Together, the results suggest that the PAI-1 inhibitor TM5275 may have therapeutic potential for asthma through suppressing eosinophilic allergic response and ameliorating airway remodeling. PMID:26702150

  16. Therapeutic potential of an orally effective small molecule inhibitor of plasminogen activator inhibitor for asthma.

    PubMed

    Liu, Rui-Ming; Eldridge, Stephanie; Watanabe, Nobuo; Deshane, Jessy; Kuo, Hui-Chien; Jiang, Chunsun; Wang, Yong; Liu, Gang; Schwiebert, Lisa; Miyata, Toshio; Thannickal, Victor J

    2016-02-15

    Asthma is one of the most common respiratory diseases. Although progress has been made in our understanding of airway pathology and many drugs are available to relieve asthma symptoms, there is no cure for chronic asthma. Plasminogen activator inhibitor 1 (PAI-1), a primary inhibitor of tissue-type and urokinase-type plasminogen activators, has pleiotropic functions besides suppression of fibrinolysis. In this study, we show that administration of TM5275, an orally effective small-molecule PAI-1 inhibitor, 25 days after ovalbumin (OVA) sensitization-challenge, significantly ameliorated airway hyperresponsiveness in an OVA-induced chronic asthma model. Furthermore, we show that TM5275 administration significantly attenuated OVA-induced infiltration of inflammatory cells (neutrophils, eosinophils, and monocytes), the increase in the levels of OVA-specific IgE and Th2 cytokines (IL-4 and IL-5), the production of mucin in the airways, and airway subepithelial fibrosis. Together, the results suggest that the PAI-1 inhibitor TM5275 may have therapeutic potential for asthma through suppressing eosinophilic allergic response and ameliorating airway remodeling.

  17. Small molecule inhibitors of HCV replication from pomegranate.

    PubMed

    Reddy, B Uma; Mullick, Ranajoy; Kumar, Anuj; Sudha, Govindarajan; Srinivasan, Narayanaswamy; Das, Saumitra

    2014-01-01

    Hepatitis C virus (HCV) is the causative agent of end-stage liver disease. Recent advances in the last decade in anti HCV treatment strategies have dramatically increased the viral clearance rate. However, several limitations are still associated, which warrant a great need of novel, safe and selective drugs against HCV infection. Towards this objective, we explored highly potent and selective small molecule inhibitors, the ellagitannins, from the crude extract of Pomegranate (Punica granatum) fruit peel. The pure compounds, punicalagin, punicalin, and ellagic acid isolated from the extract specifically blocked the HCV NS3/4A protease activity in vitro. Structural analysis using computational approach also showed that ligand molecules interact with the catalytic and substrate binding residues of NS3/4A protease, leading to inhibition of the enzyme activity. Further, punicalagin and punicalin significantly reduced the HCV replication in cell culture system. More importantly, these compounds are well tolerated ex vivo and'no observed adverse effect level' (NOAEL) was established upto an acute dose of 5000 mg/kg in BALB/c mice. Additionally, pharmacokinetics study showed that the compounds are bioavailable. Taken together, our study provides a proof-of-concept approach for the potential use of antiviral and non-toxic principle ellagitannins from pomegranate in prevention and control of HCV induced complications. PMID:24958333

  18. Small molecule inhibitors of HCV replication from Pomegranate

    NASA Astrophysics Data System (ADS)

    Reddy, B. Uma; Mullick, Ranajoy; Kumar, Anuj; Sudha, Govindarajan; Srinivasan, Narayanaswamy; Das, Saumitra

    2014-06-01

    Hepatitis C virus (HCV) is the causative agent of end-stage liver disease. Recent advances in the last decade in anti HCV treatment strategies have dramatically increased the viral clearance rate. However, several limitations are still associated, which warrant a great need of novel, safe and selective drugs against HCV infection. Towards this objective, we explored highly potent and selective small molecule inhibitors, the ellagitannins, from the crude extract of Pomegranate (Punica granatum) fruit peel. The pure compounds, punicalagin, punicalin, and ellagic acid isolated from the extract specifically blocked the HCV NS3/4A protease activity in vitro. Structural analysis using computational approach also showed that ligand molecules interact with the catalytic and substrate binding residues of NS3/4A protease, leading to inhibition of the enzyme activity. Further, punicalagin and punicalin significantly reduced the HCV replication in cell culture system. More importantly, these compounds are well tolerated ex vivo and`no observed adverse effect level' (NOAEL) was established upto an acute dose of 5000 mg/kg in BALB/c mice. Additionally, pharmacokinetics study showed that the compounds are bioavailable. Taken together, our study provides a proof-of-concept approach for the potential use of antiviral and non-toxic principle ellagitannins from pomegranate in prevention and control of HCV induced complications.

  19. IgLON cell adhesion molecules are shed from the cell surface of cortical neurons to promote neuronal growth.

    PubMed

    Sanz, Ricardo; Ferraro, Gino B; Fournier, Alyson E

    2015-02-13

    Matrix metalloproteinases and a disintegrin and metalloproteinases are members of the zinc endopeptidases, which cleave components of the extracellular matrix as well as cell surface proteins resulting in degradation or release of biologically active fragments. Surface ectodomain shedding affects numerous biological processes, including survival, axon outgrowth, axon guidance, and synaptogenesis. In this study, we evaluated the role of metalloproteinases in regulating cortical neurite growth. We found that treatment of mature cortical neurons with pan-metalloproteinase inhibitors or with tissue inhibitors of metalloproteinase-3 reduced neurite outgrowth. Through mass spectrometry, we characterized the metalloproteinase-sensitive cell surface proteome of mature cortical neurons. Members of the IgLON family of glycosylphosphatidylinositol-anchored neural cell adhesion molecules were identified and validated as proteins that were shed from the surface of mature cortical neurons in a metalloproteinase-dependent manner. Introduction of two members of the IgLON family, neurotrimin and NEGR1, in early embryonic neurons was sufficient to confer sensitivity to metalloproteinase inhibitors in neurite outgrowth assays. Outgrowth experiments on immobilized IgLON proteins revealed a role for all IgLON family members in promoting neurite extension from cortical neurons. Together, our findings support a role for metalloproteinase-dependent shedding of IgLON family members in regulating neurite outgrowth from mature cortical neurons.

  20. Serum levels of thrombomodulin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin in the acute phase of Plasmodium vivax malaria.

    PubMed

    Ohnishi, K

    1999-02-01

    Elevated plasma or serum levels of thrombomodulin (TM), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin have been reported in several diseases. However, plasma or serum levels of TM, ICAM-1, VCAM-1, and E-selectin have not been investigated in the acute phase of Plasmodium vivax malaria. Serum TM, ICAM-1, VCAM-1, E-selectin, and creatinine levels were determined in six Japanese patients in the acute phase of vivax malaria and in seven healthy Japanese controls. Parasitemias of the peripheral blood were < 0.1% in five patients and 0.8% in one patient. The patients' mean +/- SD serum levels of TM, ICAM-1, VCAM-1, and E-selectin were 5.7 +/- 1.3 Fujirebio units/ml, 709 +/- 397 ng/ml, 2,112 +/- 782 ng/ml, and 99 +/- 28 ng/ml, respectively, and all were significantly greater than those in the controls (TM; P < 0.005, ICAM-1; P < 0.025, VCAM-1; P < 0.005, E-selectin; P < 0.025). However, no significant difference was identified between patients and controls for serum creatinine values. The serum levels of TM and VCAM-1 were not related to parasitemia. The elevation of serum TM levels suggests that endothelial cell damage occurs in the acute phase of vivax malaria.

  1. Cell adhesion molecules and actin cytoskeleton at immune synapses and kinapses.

    PubMed

    Dustin, Michael L

    2007-10-01

    The immunological synapse is a stable adhesive junction between a polarized immune effector cell and an antigen-bearing cell. Immunological synapses are often observed to have a striking radial symmetry in the plane of contact with a prominent central cluster of antigen receptors surrounded by concentric rings of adhesion molecules and actin-rich projections. There is a striking similarity between the radial zones of the immunological synapse and the dynamic actinomyosin modules employed by migrating cells. Breaking the symmetry of an immunological synapse generates a moving adhesive junction that can be defined as a kinapse, which facilitates signal integration by immune cells while moving over the surface of antigen-presenting cells.

  2. The coffee diterpene kahweol inhibits tumor necrosis factor-{alpha}-induced expression of cell adhesion molecules in human endothelial cells

    SciTech Connect

    Kim, Hyung Gyun; Kim, Ji Young; Hwang, Yong Pil; Lee, Kyung Jin; Lee, Kwang Youl; Kim, Dong Hee; Kim, Dong Hyun; Jeong, Hye Gwang . E-mail: hgjeong@chosun.ac.kr

    2006-12-15

    Endothelial cells produce adhesion molecules after being stimulated with various inflammatory cytokines. These adhesion molecules play an important role in the development of atherogenesis. Recent studies have highlighted the chemoprotective and anti-inflammatory effects of kahweol, a coffee-specific diterpene. This study examined the effects of kahweol on the cytokine-induced monocyte/human endothelial cell interaction, which is a crucial early event in atherogenesis. Kahweol inhibited the adhesion of TNF{alpha}-induced monocytes to endothelial cells and suppressed the TNF{alpha}-induced protein and mRNA expression of the cell adhesion molecules, VCAM-1 and ICAM-1. Furthermore, kahweol inhibited the TNF{alpha}-induced JAK2-PI3K/Akt-NF-{kappa}B activation pathway in these cells. Overall, kahweol has anti-inflammatory and anti-atherosclerotic activities, which occurs partly by down-regulating the pathway that affects the expression and interaction of the cell adhesion molecules on endothelial cells.

  3. Cadherin transfection of Xenopus XTC cells downregulates expression of substrate adhesion molecules.

    PubMed

    Finnemann, S; Kühl, M; Otto, G; Wedlich, D

    1995-09-01

    Cadherins are discussed not in terms of their adhesive function but rather as morphoregulatory proteins. Changes in gene expression following cadherin transfection of cells in culture or by overexpression in embryos have, until now, not been reported. We established a protocol for stable transfection of Xenopus XTC cells and generated cells bearing high levels of membrane-integrated mouse uvomorulin (E-cadherin) or Xenopus XB-cadherin. These cell lines showed drastically impaired substrate adhesion on fibronectin and laminin. In immunoblot and radioimmunoprecipitation experiments, we found that fibronectin and alpha 3/beta 1 integrin are downregulated. The reduced amounts of proteins result from a decrease of the respective mRNAs as proven by RNase protection assays. Coprecipitations revealed that transfected cadherin molecules are complexed with alpha-catenin and beta-catenin at plasma membranes. However, the alpha-catenin present in the XB-cadherin complex differs immunologically from that found in the uvomorulin complex. When a truncated form of XB-cadherin lacking 38 of the most C-terminal amino acids was expressed in XTC cells, complex formation with endogenous catenins was abolished. In these transfectants, substrate adhesion was not affected. These results prove that complex formation of transfected cadherins in XTC cells with endogenous beta-catenin correlates with altered synthesis of certain substrate adhesion molecules.

  4. Markedly diminished epidermal keratinocyte expression of intercellular adhesion molecule-1 (ICAM-1) in Sezary syndrome

    SciTech Connect

    Nickoloff, B.J.; Griffiths, E.M.; Baadsgaard, O.; Voorhees, J.J.; Hanson, C.A.; Cooper, K.D. )

    1989-04-21

    In mucosis fungoides the malignant T cells express lymphocyte function-associated antigen-1, which allows them to bind to epidermal keratinocytes expressing the gamma interferon-inducible intercellular adhesion molecule-1. In this report, a patient with leukemic-stage mucosis fungoides (Sezary syndrome) had widespread erythematous dermal infiltrates containing malignant T cells, but without any epidermotropism. The authors discovered that the T cells expressed normal amounts of functional lymphocyte function-associated antigen-1, but the keratinocytes did not express significant levels of intercellular adhesion molecule-1, which was probably due to the inability of the malignant T cells to produce gamma interferon. These results support the concept that the inability of malignant T cells to enter the epidermis may contribute to emergence of more clinically aggressive T-cell clones that are no longer confined to the skin, but infiltrate the blood, lymph nodes, and viscera, as is seen in Sezary syndrome.

  5. Inflammatory and immune responses are impaired in mice deficient in intercellular adhesion molecule 1.

    PubMed Central

    Sligh, J E; Ballantyne, C M; Rich, S S; Hawkins, H K; Smith, C W; Bradley, A; Beaudet, A L

    1993-01-01

    Gene targeting was used to produce mice deficient in intercellular adhesion molecule 1 (ICAM-1) or CD54, an immunoglobulin-like cell adhesion molecule that binds beta 2 integrins. Homozygous deficient animals develop normally, are fertile, and have a moderate granulocytosis. The nature of the mutation, RNA analysis, and immunostaining are consistent with complete loss of surface expression of ICAM-1. Deficient mice exhibit prominent abnormalities of inflammatory responses including impaired neutrophil emigration in response to chemical peritonitis and decreased contact hypersensitivity to 2,4-dinitrofluorobenzene. Mutant cells provided negligible stimulation in the mixed lymphocyte reaction, although they proliferated normally as responder cells. These mutant animals will be extremely valuable for examining the role of ICAM-1 and its counterreceptors in inflammatory disease processes and atherosclerosis. Images Fig. 1 Fig. 2 PMID:8104338

  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.

  7. Nox Inhibitors & Therapies: Rational Design of Peptidic and Small Molecule Inhibitors.

    PubMed

    Cifuentes-Pagano, M Eugenia; Meijles, Daniel N; Pagano, Patrick J

    2015-01-01

    Oxidative stress-related diseases underlie many if not all of the major leading causes of death in United States and the Western World. Thus, enormous interest from both academia and pharmaceutical industry has been placed on the development of agents which attenuate oxidative stress. With that in mind, great efforts have been placed in the development of inhibitors of NADPH oxidase (Nox), the major enzymatic source of reactive oxygen species and oxidative stress in many cells and tissue. The regulation of a catalytically active Nox enzyme involves numerous protein-protein interactions which, in turn, afford numerous targets for inhibition of its activity. In this review, we will provide an updated overview of the available Nox inhibitors, both peptidic and small molecules, and discuss the body of data related to their possible mechanisms of action and specificity towards each of the various isoforms of Nox. Indeed, there have been some very notable successes. However, despite great commitment by many in the field, the need for efficacious and well-characterized, isoform-specific Nox inhibitors, essential for the treatment of major diseases as well as for delineating the contribution of a given Nox in physiological redox signalling, continues to grow.

  8. Nox Inhibitors & Therapies: Rational Design of Peptidic and Small Molecule Inhibitors

    PubMed Central

    Cifuentes-Pagano, M. Eugenia; Meijles, Daniel N.; Pagano, Patrick J.

    2016-01-01

    Oxidative stress-related diseases underlie many if not all of the major leading causes of death in United States and the Western World. Thus, enormous interest from both academia and pharmaceutical industry has been placed on the development of agents which attenuate oxidative stress. With that in mind, great efforts have been placed in the development of inhibitors of NADPH oxidase (Nox), the major enzymatic source of reactive oxygen species and oxidative stress in many cells and tissue. The regulation of a catalytically active Nox enzyme involves numerous protein-protein interactions which, in turn, afford numerous targets for inhibition of its activity. In this review, we will provide an updated overview of the available Nox inhibitors, both peptidic and small molecules, and discuss the body of data related to their possible mechanisms of action and specificity towards each of the various isoforms of Nox. Indeed, there have been some very notable successes. However, despite great commitment by many in the field, the need for efficacious and well-characterized, isoform-specific Nox inhibitors, essential for the treatment of major diseases as well as for delineating the contribution of a given Nox in physiological redox signalling, continues to grow. PMID:26510437

  9. Characterization of the inflammatory infiltrate and expression of endothelial cell adhesion molecules in lupus erythematosus tumidus.

    PubMed

    Kuhn, Annegret; Sonntag, Monika; Lehmann, Percy; Megahed, Mosaad; Vestweber, Dietmar; Ruzicka, Thomas

    2002-03-01

    Lupus erythematosus tumidus (LET) is a disease with characteristic clinical and histopathologic features that has not always been considered a subset of cutaneous lupus erythematosus (CLE). Although LET was first mentioned in the literature in 1930, it has rarely been documented, and immunohistochemical studies have never been performed. The aim of the present study was to characterize the inflammatory infiltrate and to analyze the expression of endothelial cell adhesion molecules in skin specimens from patients with LET and to compare the results with those from patients with other variants of CLE, such as discoid lupus erythematosus (DLE) and subacute cutaneous lupus erythematosus (SCLE). Cryostat sections of lesional skin specimens from ten patients with LET demonstrated an infiltrate composed of more than 75% CD4+, CD8+, and HLA-DR+ cells. Interestingly, CD45RO+ cells, in contrast to CD45RA+ cells, were the prevailing inflammatory cell population. Compared with skin specimens from patients with DLE and SCLE, the mean expression of CD4+ and CD8+ cells was higher (but not significantly so) in LET, and no differences were observed with the other three antibodies. Furthermore, in contrast to controls, intercellular adhesion molecule-1, vascular adhesion molecule-1, E-selectin, and P-selectin showed the same expression pattern in skin specimens from patients with DLE, SCLE, and LET. In conclusion, the inflammatory infiltrate of LET primarily consists of CD4+/CD8+ lymphocytes. Furthermore, expression of endothelial cell adhesion molecules was equally upregulated in LET compared with the expression in DLE and SCLE, suggesting a similar immunopathomechanism of these subtypes of CLE. PMID:12071156

  10. Cytokines and Adhesion Molecules Expression in the Brain in Human Cerebral Malaria

    PubMed Central

    Armah, Henry; Wiredu, Edwin Kwame; Dodoo, Alfred Kofi; Adjei, Andrew Anthony; Tettey, Yao; Gyasi, Richard

    2005-01-01

    Although the role of systemic proinflammatory cytokines, IL-1β and TNF-α, and their up-regulation of adhesion molecules, ICAM-1, VCAM-1 and E-Selectin, in the pathogenesis of cerebral malaria (CM) is well established, the role of local cytokine release remain unclear. Immunohistochemistry (IHC) was used to compare the expression of ICAM-1, VCAM-1, E-Selectin, IL-1β, TNF-α and TGF- β at light microscopic level in cerebral, cerebellar and brainstem postmortem cryostat sections from 10 CM, 5 severe malarial anemia (SMA), 1 purulent bacterial meningitis (PBM), 2 non-central nervous system infections (NCNSI) and 3 non-infections (NI) deaths in Ghanaian children. Fatal malaria and Salmonella sepsis showed significantly higher vascular expression of all 3 adhesion molecules, with highly significant co-localization with sequestration in the malaria cases. However, there was negligible difference between CM and SMA. TGF-β showed intravascular and perivascular distribution in all cases, but expression was most intense in the PBM case and CM group. TNF-α and IL-1β showed prominent brain parenchymal staining, in addition to intravascular and perivascular staining, in only the PBM case and CM group. The maximal expression of all 6 antigens studied was in the cerebellar sections of the malaria cases. Endothelial activation is a feature of fatal malaria and Salmonella sepsis, with adhesion molecule expression being highly correlated with sequestration. IL-1β and TNF-α are upregulated in only cases with neurodegenerative lesions, whilst TGF-β is present in all cases. Both cytokines and adhesion molecules were maximally upregulated in the cerebellar sections of the malaria cases. PMID:16705810

  11. The control of tumor vessels: what you would not expect from a neural adhesion molecule.

    PubMed

    Angiolini, Francesca; Cavallaro, Ugo

    2015-01-01

    The neural adhesion molecule L1 is involved in development and plasticity of the nervous system. We recently reported aberrant expression of L1 in the vasculature of various human tumor types. Genetic and functional inactivation of endothelial L1 in a mouse tumor model resulted in decreased tumor angiogenesis and promoted vascular normalization. Thus, endothelial L1 might represent a novel therapeutic target for vessel-targeted treatments of solid tumors. PMID:27308446

  12. Rupture of molecules upon fracture of adhesive joint between two polymer samples

    NASA Astrophysics Data System (ADS)

    Boiko, Yu. M.; Mamalimov, R. I.; Vettegren, V. I.

    2013-07-01

    The surfaces formed after fracture of the joint of two polystyrene (PS) samples have been studied by attenuated total reflection Fourier-transform infrared spectroscopy. The adhesive joint between samples was created by pressing them one against another and holding at a pressure of 0.8 MPa and a temperature of 80°C, which is ˜23°C lower than the glass transition temperature of PS. It has been found that, after the joint fracture, the concentration of molecule ends formed after the rupture of carbon-carbon bonds in the back-bone of the PS molecule increases.

  13. Cellular Adhesion Molecules in Healthy Subjects: Short Term Variations and Relations to Flow Mediated Dilation.

    PubMed

    Eschen, Ole; Christensen, Jeppe Hagstrup; Dethlefsen, Claus; Schmidt, Erik Berg

    2008-01-01

    The objective was primarily to describe short term intra-individual variation in serum levels of soluble adhesion molecules (sCAMs: E-selectin, P-selectin, intercellular adhesion molecule-1(sICAM-1) and vascular cellular adhesion molecule-1(sVCAM-1)) in healthy subjects. Secondly, sCAMs were correlated to brachial artery flow mediated vasodilation (FMD).Forty healthy subjects aged 24-66 years had sCAMs measured twice with 4 week intervals and short-term intra-individual variation was estimated as variation in the paired measurements after correcting for the analytical precision of the used method. At baseline, brachial FMD was measured.No difference was observed in mean sCAMs in the whole study group. Estimated intra-subject variations in sCAMs were 7.6-11.3%. In a regression analysis, significant negative association was found between sE-selectin and FMD after controlling for possible confounders (p < 0.04) while no significant correlation could be demonstrated between the other sCAMs and FMD.In conclusion, short term intra-individual variations in sCAMs were 7.6-11.3% in healthy subjects. We also found a significant negative association between sE-selectin and FMD, indicating an possible association between inflammation and dysfunction of the vascular endothelium; however further studies are required to confirm this preliminary finding.

  14. The role of soluble cell adhesion molecules in patients with suspected deep vein thrombosis.

    PubMed

    Bucek, Robert A; Reiter, Markus; Quehenberger, Peter; Minar, Erich; Baghestanian, Mehrdad

    2003-10-01

    Activation of the endothelium, platelets and leukocytes has been shown to play an important role in the aetiology of deep venous thrombosis (DVT) in in-vitro experiments, resulting in the release of soluble cell adhesion molecules (sCAMs). We therefore assessed the value of soluble intracellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble E-selectin and soluble P-selectin for the diagnostic process in 69 consecutive patients with suspected DVT. Final diagnosis was based on the results of Duplex sonography or ascending venography. Thirty-seven patients (53.6%) finally suffered from DVT. Mean levels of sVCAM-1 were 589 +/- 530 ng/ml for controls and 587 +/- 328 ng/ml for patients. Corresponding levels concerning sICAM-1 were 316 +/- 161 and 342 +/- 186 ng/ml, those concerning soluble E-selectin were 54 +/- 38 and 42 +/- 18 ng/ml, and those concerning soluble P-selectin were 94 +/- 37 and 99 +/- 36 ng/ml (all P > 0.05). There was no significant correlation of the thrombus extension (all P > 0.05) or the duration of symptoms with sCAMs (all P > 0.05). In conclusion, we detected no significant differences concerning the concentration of four major sCAMs between patients with DVT and controls, so their assessment does not add any useful information for the diagnostic process of DVT.

  15. Synaptic adhesion molecule IgSF11 regulates synaptic transmission and plasticity

    PubMed Central

    Shin, Hyewon; van Riesen, Christoph; Whitcomb, Daniel; Warburton, Julia M.; Jo, Jihoon; Kim, Doyoun; Kim, Sun Gyun; Um, Seung Min; Kwon, Seok-kyu; Kim, Myoung-Hwan; Roh, Junyeop Daniel; Woo, Jooyeon; Jun, Heejung; Lee, Dongmin; Mah, Won; Kim, Hyun; Kaang, Bong-Kiun; Cho, Kwangwook; Rhee, Jeong-Seop; Choquet, Daniel; Kim, Eunjoon

    2016-01-01

    Summary Synaptic adhesion molecules regulate synapse development and plasticity through mechanisms including trans-synaptic adhesion and recruitment of diverse synaptic proteins. We report here that the immunoglobulin superfamily member 11 (IgSF11), a homophilic adhesion molecule preferentially expressed in the brain, is a novel and dual-binding partner of the postsynaptic scaffolding protein PSD-95 and AMPAR glutamate receptors (AMPARs). IgSF11 requires PSD-95 binding for its excitatory synaptic localization. In addition, IgSF11 stabilizes synaptic AMPARs, as shown by IgSF11 knockdown-induced suppression of AMPAR-mediated synaptic transmission and increased surface mobility of AMPARs, measured by high-throughput, single-molecule tracking. IgSF11 deletion in mice leads to suppression of AMPAR-mediated synaptic transmission in the dentate gyrus and long-term potentiation in the CA1 region of the hippocampus. IgSF11 does not regulate the functional characteristics of AMPARs, including desensitization, deactivation, or recovery. These results suggest that IgSF11 regulates excitatory synaptic transmission and plasticity through its tripartite interactions with PSD-95 and AMPARs. PMID:26595655

  16. Differential Associations between CDH13 Genotypes, Adiponectin Levels, and Circulating Levels of Cellular Adhesive Molecules

    PubMed Central

    Teng, Ming-Sheng; Wu, Semon; Hsu, Lung-An; Chou, Hsin-Hua; Ko, Yu-Lin

    2015-01-01

    CDH13 gene variants with lower adiponectin levels are paradoxically associated with a more favorable metabolic profile. We investigated the statistical association between CDH13 locus variants and adiponectin levels by examining 12 circulating inflammation marker levels and adiposity status in 530 Han Chinese people in Taiwan. After adjustments for clinical covariates, adiponectin levels were positively associated with soluble vascular cell adhesion molecule-1 (sVCAM1) levels and negatively associated with adiposity status and levels of C-reactive protein (CRP), soluble E-selectin (sE-selectin), and soluble intercellular adhesion molecule-1 (sICAM1). In addition, minor alleles of the CDH13 rs12051272 polymorphism were found to have lower adiponectin levels and higher CRP, sE-selectin, sICAM1, and sVCAM1 levels as well as higher body mass indices and waist circumferences in participants (all P < 0.05). In a subgroup analysis stratified by sex, significant associations between CDH13 genotypes and sE-selectin levels occurred only in men (P = 3.9 × 10−4 and interaction P = 0.005). CDH13 locus variants and adiponectin levels are associated with circulating levels of cellular adhesion molecules and adiposity status in a differential manner that interacts with sex. These results provide further evidence for the crucial role of adiponectin levels and CDH13 gene variants in immune-mediated and inflammatory diseases. PMID:26600672

  17. Erythroid Adhesion Molecules in Sickle Cell Anaemia Infants: Insights Into Early Pathophysiology

    PubMed Central

    Brousse, Valentine; Colin, Yves; Pereira, Catia; Arnaud, Cecile; Odièvre, Marie Helene; Boutemy, Anne; Guitton, Corinne; de Montalembert, Mariane; Lapouméroulie, Claudine; Picot, Julien; Le Van Kim, Caroline; El Nemer, Wassim

    2014-01-01

    Sickle cell anaemia (SCA) results from a single mutation in the β globin gene. It is seldom symptomatic in the first semester of life. We analysed the expression pattern of 9 adhesion molecules on red blood cells, in a cohort of 54 SCA and 17 non-SCA very young infants of comparable age (median 144 days, 81–196). Haemoglobin F (HbF) level was unsurprisingly elevated in SCA infants (41.2% ± 11.2) and 2–4 fold higher than in non-SCA infants, yet SCA infants presented significantly decreased Hb level and increased reticulocytosis. Cytometry analysis evidenced a specific expression profile on reticulocytes of SCA infants, with notably an increased expression of the adhesion molecules Lu/BCAM, ICAM-4 and LFA-3, both in percentage of positive cells and in surface density. No significant difference was found on mature red cells. Our findings demonstrate the very early onset of reticulocyte membrane modifications in SCA asymptomatic infants and allow an insight into the first pathological changes with the release of stress reticulocytes expressing a distinctive profile of adhesion molecules. PMID:26137540

  18. Mobilization of NK cells by exercise: downmodulation of adhesion molecules on NK cells by catecholamines.

    PubMed

    Nagao, F; Suzui, M; Takeda, K; Yagita, H; Okumura, K

    2000-10-01

    The change of plasma catecholamine concentration correlates with the change of natural killer (NK) activity and NK cell number in peripheral blood mononuclear cells (PBMC) during and after moderate exercise. We studied the causal relation between exercise-induced catecholamine and expression of adhesion molecules on NK cells during and after exercise. The expression of CD44 and CD18 on CD3(-)CD56(+) NK cells was significantly reduced during exercise (P < 0.01). When PBMC were stimulated with 10(-8)M norepinephrine in vitro, the expression of these adhesion molecules on CD3(-)CD56(+) NK cells was downmodulated within 30 min. The binding capacity of NK cells to a CD44 ligand, hyaluronate, was reduced by the stimulation with norepinephrine (P < 0.01). The intravenous injection of norepinephrine in mice decreased the expression of CD44 and CD18 on CD3(-)NK1.1(+) cells (P < 0.01) and increased the number of CD3(-)NK1.1(+) cells in PBMC (P < 0.01). These findings suggest that exercise-induced catecholamines modulate the expression of adhesion molecules on NK cells, resulting in the mobilization of NK cells into the circulation. PMID:11003990

  19. Correlation between the levels of circulating adhesion molecules and atherosclerosis in type-2 diabetic normotensive patients

    PubMed Central

    Vargas-Robles, Hilda; Serrano, Alberto Maceda; Lozano-Nuevo, Jose Juan; Escalante-Acosta, Bruno Alfonso

    2009-01-01

    Endothelial dysfunction is a common feature in type-2 diabetic patients and is associated with inflammation, increased levels of circulating soluble adhesion molecules and atherosclerosis. The aim of this study was to evaluate the relationship between the levels of circulating soluble adhesion molecules and the degree of atherosclerosis in normotensive type-2 diabetic patients. Results: We found significant correlations between ICAM-1 (r = 0.69, p < 0.001 95% IC 0.65 to 0.82) and VCAM-1 (r = 0.4, p < 0.03, 95% IC 0.65 to 0.82) levels and maximal carotid artery intimal-medial thickness, whereas no correlation was observed with E-selectin. Methods: We studied 30 normotensive type-2 diabetic patients in whom VCAM-1, ICAM-1 and E-selectin were measured by ELISA. Additionally, the intimal-medial thickness of both the common and internal carotid arteries was measured (B-mode ultrasound). The levels of circulating adhesion molecules and maximal carotid artery intimal-medial thicknesses were correlated using the Spearman correlation coefficient test. Statistical analysis was performed with ANOVA. Conclusion: Our results suggest that ICAM-1 and VCAM-1 are markers associated, and correlated with the degree of atherosclerosis in normotensive type-2 diabetic patients. PMID:19717975

  20. Differential expression of epithelial cell adhesion molecule in salivary gland neoplasms.

    PubMed

    Phattarataratip, Ekarat; Masorn, Marisa; Jarupoonphol, Werapong; Supatthanayut, Sirinpaporn; Saeoweiang, Pichanee

    2016-10-01

    Epithelial cell adhesion molecule (EpCAM) is the epithelial-specific molecule expressed on various epithelial cell types. The function of EpCAM involves cellular adhesion, proliferation, and signaling in both normal tissues and cancers. The purposes of this study were to investigate the EpCAM expression in salivary gland neoplasms and examine its relationship with pathologic characteristics. Forty-two cases of salivary gland neoplasms, including 20 mucoepidermoid carcinomas (MECs), 11 adenoid cystic carcinomas (ACCs), 9 pleomorphic adenomas (PAs), and 2 polymorphous low-grade adenocarcinomas (PLGAs) were enrolled. Epithelial cell adhesion molecule expression was analyzed immunohistochemically using MOC-31 and BerEP4 antibodies. Results showed that the majority of MECs and all PLGAs showed EpCAM expression in more than 50% of neoplastic cells, whereas most PAs and ACCs did not express this protein. In MECs, most EpCAM-positive neoplastic cells were clear cells, glandular epithelial cells, and intermediate cells, whereas squamous cells and mucous cells were largely negative. The expression was limited to ductal epithelium in EpCAM-positive PAs and ACCs. The decreased EpCAM expression in MECs was significantly associated with microscopically diminished cystic components, the presence of small nest invasion at invasive front, cellular anaplasia, vascular invasion, and high pathologic grade. These data suggested that EpCAM showed different expression pattern among salivary gland neoplasms and in different grades of MECs. PMID:27649957

  1. [Allergens-induced sensitization alters airway epithelial adhesion molecules expression in mice].

    PubMed

    Zeng, Dan; Tan, Mei-Ling; Xiang, Yang; Qin, Xiao-Qun; Zhu, Li-Ming; Dai, Ai-Guo

    2015-12-25

    To explore the relationship between the epithelial adhesion molecules and immune responses of airway epithelium, we observed the expression of integrin β4 and intercellular adhesion molecule-1 (ICAM-1) in the mice airway epithelium after sensitization with allergens. BALB/c mice were sensitized with intraperitoneal injection of ovalbumin (OVA) or house dust mite (HDM) and then developed airway hyper-responsiveness as determined by barometric whole-body plethysmography. Both OVA and HDM sensitization led to increases of the number of peripheral leukocytes as well as inflammatory cells infiltration in lungs. OVA sensitized mice showed more severe inflammatory cells infiltration than HDM sensitized mice. Immunohistochemistry analysis of mice lung tissues revealed that sensitization with both allergens also led to a decrease of integrin β4 expression and an increase of ICAM-1 expression in airway epithelia. OVA sensitized mice showed a more significant increase of ICAM-1 expression compared with HDM sensitized mice. siRNA mediated silencing of integrin β4 gene in 16HBE cells resulted in an up-regulation of ICAM-1 expression. Our results indicate a possible role of airway epithelial adhesion molecules in allergen-induced airway immune responses. PMID:26701635

  2. Small-Molecule Inhibitors of the Myc Oncoprotein

    PubMed Central

    Fletcher, Steven; Prochownik, Edward V.

    2014-01-01

    The c-Myc (Myc) oncoprotein is among the most attractive of cancer targets given that is deregulated in the majority of tumors and that its inhibition profoundly affects their growth and/or survival. However, its role as a seldom-mutated transcription factor, its lack of enzymatic activity for which suitable pharmaceutical inhibitors could be crafted and its expression by normal cells have largely been responsible for its being viewed as “undruggable”. Work over the past several years, however, has begun to reverse this idea by allowing us to view Myc within the larger context of global gene regulatory control. Thus, Myc and its obligate heterodimeric partner, Max, are integral to the coordinated recruitment and post-translational modification of components of the core transcriptional machinery. Moreover, Myc over-expression re-programs numerous critical cellular functions and alters the cell’s susceptibility to their inhibition. This new knowledge has therefore served as a framework upon which to develop new pharmaceutical approaches. These include the continuing development of small molecules which act directly to inhibit the critical Myc-Max interaction, those which act indirectly to prevent Myc-directed post-translational modifications necessary to initiate productive transcription and those which inhibit vital pathways upon which the Myc-transformed cell is particularly reliant. PMID:24657798

  3. Micromanipulation of adhesion of phorbol 12-myristate-13-acetate-stimulated T lymphocytes to planar membranes containing intercellular adhesion molecule-1.

    PubMed Central

    Tözeren, A; Mackie, L H; Lawrence, M B; Chan, P Y; Dustin, M L; Springer, T A

    1992-01-01

    This paper presents an analytical and experimental methodology to determine the physical strength of cell adhesion to a planar membrane containing one set of adhesion molecules. In particular, the T lymphocyte adhesion due to the interaction of the lymphocyte function associated molecule 1 on the surface of the cell, with its counter-receptor, intercellular adhesion molecule-1 (ICAM-1), on the planar membrane, was investigated. A micromanipulation method and mathematical analysis of cell deformation were used to determine (a) the area of conjugation between the cell and the substrate and (b) the energy that must be supplied to detach a unit area of the cell membrane from its substrate. T lymphocytes stimulated with phorbol 12-myristate-13-acetate (PMA) conjugated strongly with the planar membrane containing purified ICAM-1. The T lymphocytes attached to the planar membrane deviated occasionally from their round configuration by extending pseudopods but without changing the size of the contact area. These adherent cells were dramatically deformed and then detached when pulled away from the planar membrane by a micropipette. Detachment occurred by a gradual decrease in the radius of the contact area. The physical strength of adhesion between a PMA-stimulated T lymphocyte and a planar membrane containing 1,000 ICAM-1 molecules/micron 2 was comparable to the strength of adhesion between a cytotoxic T cell and its target cell. The comparison of the adhesive energy density, measured at constant cell shape, with the model predictions suggests that the physical strength of cell adhesion may increase significantly when the adhesion bonds in the contact area are immobilized by the actin cytoskeleton. Images FIGURE 2 FIGURE 4 FIGURE 5 FIGURE 8 FIGURE 9 PMID:1358239

  4. Identification of a small molecule [beta]-secretase inhibitor that binds without catalytic aspartate engagement

    SciTech Connect

    Steele, Thomas G.; Hills, Ivory D.; Nomland, Ashley A.; de León, Pablo; Allison, Timothy; McGaughey, Georgia; Colussi, Dennis; Tugusheva, Katherine; Haugabook, Sharie J.; Espeseth, Amy S.; Zuck, Paul; Graham, Samuel L.; Stachel, Shawn J.

    2010-09-02

    A small molecule inhibitor of beta-secretase with a unique binding mode has been developed. Crystallographic determination of the enzyme-inhibitor complex shows the catalytic aspartate residues in the active site are not engaged in inhibitor binding. This unprecedented binding mode in the field of aspartyl protease inhibition is described.

  5. EA-1, a novel adhesion molecule involved in the homing of progenitor T lymphocytes to the thymus

    PubMed Central

    1991-01-01

    The mouse progenitor T lymphocyte (pro-T) cell line FTF1 binds in vitro to thymus blood vessels, the thymic capsule, and liver from newborn mice. A mAb, EA-1, raised against an embryonic mouse endothelial cell line, blocked adhesion. The antibody also interfered with pro-T cell adhesion to a thymus-derived mouse endothelial cell line; it had no effect on the adhesion of mature T lymphocytes and myeloid cells. The antigen recognized by EA-1 is located on the vascular endothelium of various mouse tissues and absent on pro-T cells. EA-1 antibody precipitates molecules with apparent molecular weights of 110,000, 140,000, 160,000, and 200,000. Immunoclearing and binding-inhibition studies with antibodies against known adhesion molecules suggest that the EA-1 antigen is a novel adhesion molecule involved in colonization of the embryonic thymus by T cell progenitors. PMID:1874787

  6. Dual role of melanoma cell adhesion molecule (MCAM)/CD146 in lymphocyte endothelium interaction: MCAM/CD146 promotes rolling via microvilli induction in lymphocyte and is an endothelial adhesion receptor.

    PubMed

    Guezguez, Borhane; Vigneron, Pascale; Lamerant, Nathalie; Kieda, Claudine; Jaffredo, Thierry; Dunon, Dominique

    2007-11-15

    The melanoma cell adhesion molecule (MCAM)/CD146 is expressed as two isoforms differing by their cytoplasmic domain (MCAM long (MCAM-l) and MCAM short (MCAM-s)). MCAM being expressed by endothelial cells and activated T cells, we analyzed its involvement in lymphocyte trafficking. The NK cell line NKL1 was transfected by MCAM isoforms and submitted to adhesion on both the endothelial cell monolayer and recombinant molecules under shear stress. MCAM-l transfection reduced rolling velocity and increased NKL1 adhesion on the endothelial cell monolayer and VCAM-1. Scanning electron microscopy revealed that MCAM-l induced microvilli formation and extension. In contrast, MCAM short or mock transfection had no effect on adhesion of NKL1 cells and microvilli formation. As shown by mutagenesis, serine 32 of the MCAM-l cytoplasmic tail, belonging to a putative protein kinase C phosphorylation site, was necessary for MCAM-l-actin cytoskeleton interaction and microvilli induction. Accordingly, chelerythrine chloride, a protein kinase C inhibitor, abolished MCAM-l-induced microvilli and rolling of MCAM-l-transfected NKL1 cells. Inhibition of adhesion under shear stress by anti-MCAM Abs suggested that both lymphoid MCAM-l and endothelial MCAM were also directly involved in lymphocyte endothelium interaction. MCAM-l-transfected NKL1 and activated CD4 T cells adhered to rMCAM under shear stress whereas anti-MCAM Ab treatment inhibited this process. Taken together, these data establish that MCAM is involved in the initial steps of lymphocyte endothelium interaction. By promoting the rolling on the inflammation marker VCAM-1 via microvilli induction and displaying adhesion receptor activity involving possible homophilic MCAM-l-MCAM-l interactions, MCAM might be involved in the recruitment of activated T cells to inflammation sites.

  7. Crystal Structure of an Engineered LRRTM2 Synaptic Adhesion Molecule and a Model for Neurexin Binding.

    PubMed

    Paatero, Anja; Rosti, Katja; Shkumatov, Alexander V; Sele, Celeste; Brunello, Cecilia; Kysenius, Kai; Singha, Prosanta; Jokinen, Ville; Huttunen, Henri; Kajander, Tommi

    2016-02-16

    Synaptic adhesion molecules are key components in development of the brain, and in the formation of neuronal circuits, as they are central in the assembly and maturation of chemical synapses. Several families of neuronal adhesion molecules have been identified such as the neuronal cell adhesion molecules, neurexins and neuroligins, and in particular recently several leucine-rich repeat proteins, e.g., Netrin G-ligands, SLITRKs, and LRRTMs. The LRRTMs form a family of four proteins. They have been implicated in excitatory glutamatergic synapse function and were specifically characterized as ligands for neurexins in excitatory synapse formation and maintenance. In addition, LRRTM3 and LRRTM4 have been found to be ligands for heparan sulfate proteoglycans, including glypican. We report here the crystal structure of a thermostabilized mouse LRRTM2, with a Tm 30 °C higher than that of the wild-type protein. We localized the neurexin binding site to the concave surface based on protein engineering, sequence conservation, and prior information about the interaction of the ligand with neurexins, which allowed us to propose a tentative model for the LRRTM-neurexin interaction complex. We also determined affinities of the thermostabilized LRRTM2 and wild-type LRRTM1 and LRRTM2 for neurexin-β1 with and without Ca(2+). Cell culture studies and binding experiments show that the engineered protein is functional and capable of forming synapselike contacts. The structural and functional data presented here provide the first structure of an LRRTM protein and allow us to propose a model for the molecular mechanism of LRRTM function in the synaptic adhesion.

  8. Adhesion

    MedlinePlus

    ... as the shoulder Eyes Inside the abdomen or pelvis Adhesions can become larger or tighter over time. ... Other causes of adhesions in the abdomen or pelvis include: Appendicitis , most often when the appendix breaks ...

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

    SciTech Connect

    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. - 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

  10. Adhesion of single polyelectrolyte molecules on silica, mica, and bitumen surfaces.

    PubMed

    Long, Jun; Xu, Zhenghe; Masliyah, Jacob H

    2006-02-14

    In a recent study (Energy Fuels 2005, 19, 936), a partially hydrolyzed polyacrylamide (HPAM) was used as a process aid to recover bitumen from oil sand ores. It was found that HPAM addition at the bitumen extraction step not only improved bitumen recovery but also enhanced fine solids settling in the tailings stream. To understand the role of HPAM, single-molecule force spectroscopy was employed for the first time to measure the desorption/adhesion forces of single HPAM molecules on silica, mica, and bitumen surfaces using an atomic force microscope (AFM). Silicon wafers with an oxidized surface layer and newly cleaved mica were used, respectively, to represent sand grains and clays in oil sands. The force measurements were carried out in deionized water and in commercial plant process water under equilibrium conditions. The desorption/adhesion forces of HPAM obtained on mica, silica, and bitumen surfaces were approximately 200, 40, and 80 pN in deionized water and approximately 100, 50, and 40 pN in the plant process water, respectively. The measured adhesion forces together with the zeta potential values of these surfaces indicate that the polymer would preferentially adsorb onto clay surfaces rather than onto bitumen surfaces. It is the selective adsorption of HPAM that benefits both bitumen recovery and tailings settling when the polymer was added directly to the bitumen extraction process at an appropriate dosage.

  11. Depletion of water molecules during ethanol wet-bonding with etch and rinse dental adhesives.

    PubMed

    Grégoire, Geneviève; Sharrock, Patrick; Delannée, Mathieu; Delisle, Marie-Bernadette

    2013-01-01

    The treatment of demineralized dentin with ethanol has been proposed as a way to improve hydrophobic monomer penetration into otherwise water saturated collagen fibrils. The ethanol rinse is expected to preserve the fibrils from collapsing while optimizing resin constituent infiltration for better long term adhesion. The physico-chemical investigations of demineralized dentin confirmed objectively these working hypotheses. Namely, Differential Scanning Calorimetry (DSC) measurements of the melting point of water molecules pointed to the presence of free and bound water states. Unfreezable water was the main type of water remaining following a rinsing step with absolute ethanol. Two different liquid water phases were also observed by Magic Angle Spinning (MAS) solid state Nuclear magnetic Resonance (NMR) spectroscopy. Infrared spectra of ethanol treated specimens illustrated differences with the fully hydrated specimens concerning the polar carbonyl vibrations. Optical microscopy observations as well as scanning electron microscopy showed an improved dentin-adhesive interface with ethanol wet bonding. The results indicate that water can be confined to strongly bound structural molecules when excess water is removed with ethanol prior to adhesive application. This should preserve collagen from hydrolysis upon aging of the hybrid layer.

  12. The cell adhesion molecule Fasciclin2 regulates brush border length and organization in Drosophila renal tubules

    PubMed Central

    Halberg, Kenneth A.; Rainey, Stephanie M.; Veland, Iben R.; Neuert, Helen; Dornan, Anthony J.; Klämbt, Christian; Davies, Shireen-Anne; Dow, Julian A. T.

    2016-01-01

    Multicellular organisms rely on cell adhesion molecules to coordinate cell–cell interactions, and to provide navigational cues during tissue formation. In Drosophila, Fasciclin 2 (Fas2) has been intensively studied due to its role in nervous system development and maintenance; yet, Fas2 is most abundantly expressed in the adult renal (Malpighian) tubule rather than in neuronal tissues. The role Fas2 serves in this epithelium is unknown. Here we show that Fas2 is essential to brush border maintenance in renal tubules of Drosophila. Fas2 is dynamically expressed during tubule morphogenesis, localizing to the brush border whenever the tissue is transport competent. Genetic manipulations of Fas2 expression levels impact on both microvilli length and organization, which in turn dramatically affect stimulated rates of fluid secretion by the tissue. Consequently, we demonstrate a radically different role for this well-known cell adhesion molecule, and propose that Fas2-mediated intermicrovillar homophilic adhesion complexes help stabilize the brush border. PMID:27072072

  13. The cell adhesion molecule Fasciclin2 regulates brush border length and organization in Drosophila renal tubules.

    PubMed

    Halberg, Kenneth A; Rainey, Stephanie M; Veland, Iben R; Neuert, Helen; Dornan, Anthony J; Klämbt, Christian; Davies, Shireen-Anne; Dow, Julian A T

    2016-01-01

    Multicellular organisms rely on cell adhesion molecules to coordinate cell-cell interactions, and to provide navigational cues during tissue formation. In Drosophila, Fasciclin 2 (Fas2) has been intensively studied due to its role in nervous system development and maintenance; yet, Fas2 is most abundantly expressed in the adult renal (Malpighian) tubule rather than in neuronal tissues. The role Fas2 serves in this epithelium is unknown. Here we show that Fas2 is essential to brush border maintenance in renal tubules of Drosophila. Fas2 is dynamically expressed during tubule morphogenesis, localizing to the brush border whenever the tissue is transport competent. Genetic manipulations of Fas2 expression levels impact on both microvilli length and organization, which in turn dramatically affect stimulated rates of fluid secretion by the tissue. Consequently, we demonstrate a radically different role for this well-known cell adhesion molecule, and propose that Fas2-mediated intermicrovillar homophilic adhesion complexes help stabilize the brush border. PMID:27072072

  14. Small molecule inhibitors of IRES-mediated translation

    PubMed Central

    Vaklavas, Christos; Meng, Zheng; Choi, Hyoungsoo; Grizzle, William E; Zinn, Kurt R; Blume, Scott W

    2015-01-01

    Many genes controlling cell proliferation and survival (those most important to cancer biology) are now known to be regulated specifically at the translational (RNA to protein) level. The internal ribosome entry site (IRES) provides a mechanism by which the translational efficiency of an individual or group of mRNAs can be regulated independently of the global controls on general protein synthesis. IRES-mediated translation has been implicated as a significant contributor to the malignant phenotype and chemoresistance, however there has been no effective means by which to interfere with this specialized mode of protein synthesis. A cell-based empirical high-throughput screen was performed in attempt to identify compounds capable of selectively inhibiting translation mediated through the IGF1R IRES. Results obtained using the bicistronic reporter system demonstrate selective inhibition of second cistron translation (IRES-dependent). The lead compound and its structural analogs completely block de novo IGF1R protein synthesis in genetically-unmodified cells, confirming activity against the endogenous IRES. Spectrum of activity extends beyond IGF1R to include the c-myc IRES. The small molecule IRES inhibitor differentially modulates synthesis of the oncogenic (p64) and growth-inhibitory (p67) isoforms of Myc, suggesting that the IRES controls not only translational efficiency, but also choice of initiation codon. Sustained IRES inhibition has profound, detrimental effects on human tumor cells, inducing massive (>99%) cell death and complete loss of clonogenic survival in models of triple-negative breast cancer. The results begin to reveal new insights into the inherent complexity of gene-specific translational regulation, and the importance of IRES-mediated translation to tumor cell biology. PMID:26177060

  15. Nerve growth factor translates stress response and subsequent murine abortion via adhesion molecule-dependent pathways.

    PubMed

    Tometten, Mareike; Blois, Sandra; Kuhlmei, Arne; Stretz, Anna; Klapp, Burghard F; Arck, Petra C

    2006-04-01

    Spontaneous abortion is a frequent threat affecting 10%-25% of human pregnancies. Psychosocial stress has been suggested to be attributable for pregnancy losses by challenging the equilibrium of systems mandatory for pregnancy maintenance, including the nervous, endocrine, and immune system. Strong evidence indicates that stress-triggered abortion is mediated by adhesion molecules, i.e., intercellular adhesion molecule 1 (ICAM1) and leukocyte function associated molecule 1, now being referred to as integrin alpha L (ITGAL), which facilitate recruitment of inflammatory cells to the feto-maternal interface. The neurotrophin beta-nerve growth factor (NGFB), which has been shown to be upregulated in response to stress in multiple experimental settings including in the uterine lining (decidua) during pregnancy, increases ICAM1 expression on endothelial cells. Here, we investigated whether and how NGFB neutralization has a preventive effect on stress-triggered abortion in the murine CBA/J x DBA/2J model. We provide experimental evidence that stress exposure upregulates the frequency of abortion and the expression of uterine NGFB. Further, adhesion molecules ICAM1 and selectin platelet (SELP, formerly P-Selectin) and their ligands ITGAL and SELP ligand (SELPL, formerly P selectin glycoprotein ligand 1) respectively increase in murine deciduas in response to stress. Subsequently, decidual cytokines are biased toward a proinflammatory and abortogenic cytokine profile. Additionally, a decrease of pregnancy protective CD8alpha(+) decidual cells is present. Strikingly, all such uterine stress responses are abrogated by NGFB neutralization. Hence, NGFB acts as a proximal mediator in the hierarchical network of immune rejection by mediating an abortogenic environment comprised of classical signs of neurogenic inflammation. PMID:16371592

  16. Platelet endothelial cell adhesion molecule-1 and mechanotransduction in vascular endothelial cells.

    PubMed

    Fujiwara, K

    2006-04-01

    Endothelial cells are known to respond to mechanical forces such as fluid shear stress and cyclic stretch, but elucidating the mechanism for mechanosensing has been difficult. Experimental data indicate that there are probably several sensing mechanisms. We have recently proposed a novel mechanoresponse mechanism that involves platelet endothelial cell adhesion molecule-1 (PECAM-1). When endothelial cells are stimulated by fluid shear stress, PECAM-1 is tyrosine phosphorylated and activates the extracellular signal-regulated kinase 1 and 2 (ERK1/2) signalling cascade. The same signalling events occurred when we applied pulling force directly on PECAM-1 on the endothelial cell surface using magnetic beads coated with antibodies against the external domain of PECAM-1. These results appear to indicate that PECAM-1 is a mechanotransduction molecule. To our knowledge, this is the first mammalian molecule that is shown to respond to mechanical force directly exerted to it. PMID:16594905

  17. Hedgehog inhibitors selectively target cell migration and adhesion of mantle cell lymphoma in bone marrow microenvironment

    PubMed Central

    Zhang, Han; Chen, Zheng; Neelapu, Sattva S.; Romaguera, Jorge; McCarty, Nami

    2016-01-01

    The clinical benefits of a Hedgehog (Hh) inhibitor, LDE225 (NPV-LDE-225, Erismodegib), have been unclear in hematological cancers. Here, we report that LDE225 selectively inhibited migration and adhesion of mantle cell lymphoma (MCL) to bone marrows via very late antigen-4 (VLA-4) mediated inactivation of focal adhesion kinase (FAK) signaling. LDE225 treatment not only affected MCL cells, but also modulated stromal cells within the bone marrow microenvironment by decreasing their production of SDF-1, IL-6 and VCAM-1, the ligand for VLA-4. Surprisingly, LDE225 treatment alone did not suppress cell proliferation due to increased CXCR4 expression mediated by reactive oxygen species (ROS). The increased ROS/CXCR4 further stimulated autophagy formation. The combination of LDE225 with the autophagy inhibitors further enhanced MCL cell death. Our data, for the first time, revealed LDE225 selectively targets MCL cells migration and adhesion to bone marrows. The ineffectiveness of LDE225 in MCL is due to autophagy formation, which in turn increases cell viability. Inhibiting autophagy will be an effective adjuvant therapy for LDE225 in MCL, especially for advanced MCL patients with bone marrow involvement. PMID:26885608

  18. Hedgehog inhibitors selectively target cell migration and adhesion of mantle cell lymphoma in bone marrow microenvironment.

    PubMed

    Zhang, Han; Chen, Zheng; Neelapu, Sattva S; Romaguera, Jorge; McCarty, Nami

    2016-03-22

    The clinical benefits of a Hedgehog (Hh) inhibitor, LDE225 (NPV-LDE-225, Erismodegib), have been unclear in hematological cancers. Here, we report that LDE225 selectively inhibited migration and adhesion of mantle cell lymphoma (MCL) to bone marrows via very late antigen-4 (VLA-4) mediated inactivation of focal adhesion kinase (FAK) signaling. LDE225 treatment not only affected MCL cells, but also modulated stromal cells within the bone marrow microenvironment by decreasing their production of SDF-1, IL-6 and VCAM-1, the ligand for VLA-4. Surprisingly, LDE225 treatment alone did not suppress cell proliferation due to increased CXCR4 expression mediated by reactive oxygen species (ROS). The increased ROS/CXCR4 further stimulated autophagy formation. The combination of LDE225 with the autophagy inhibitors further enhanced MCL cell death. Our data, for the first time, revealed LDE225 selectively targets MCL cells migration and adhesion to bone marrows. The ineffectiveness of LDE225 in MCL is due to autophagy formation, which in turn increases cell viability. Inhibiting autophagy will be an effective adjuvant therapy for LDE225 in MCL, especially for advanced MCL patients with bone marrow involvement. PMID:26885608

  19. Adhesion, stretching, and electrical charge assessment of dermatan sulfate molecules by colloidal probes.

    PubMed

    Gonzalez, Rodrigo; Caballero, Leonardo; Pavez, Jorge; Melo, Francisco

    2012-06-26

    Electrical and mechanical properties of dermatan sulfate (DS) molecules are studied in an aqueous environment as a function of pH. DS molecules linked at various points distributed on the surface of mica previously silanizated along with a suitable functionalized microsphere, attached to the cantilever of an atomic force microscope (AFM), provided suitable surfaces for testing interactions through the colloidal probe methodology. The repulsive force between the surfaces indicated that the charge of DS increases with pH as a result of the gradual deprotonation of acidic groups. Pulling experiments revealed increasing adhesion of DS to the monolayer as a function of pH, presumably due both to the electrical nature of the interaction between these molecules and the progressive increase of the charge of DS with pH. Serrations exhibited by the force in pulling experiments indicate that more than a single DS molecule is stretched at the same time. In addition, pulling force remained significant even at extensions that went beyond the average contour length of a single DS molecule, which suggests the existence of a significant link between DS molecules.

  20. Cilostazol prevents remnant lipoprotein particle-induced monocyte adhesion to endothelial cells by suppression of adhesion molecules and monocyte chemoattractant protein-1 expression via lectin-like receptor for oxidized low-density lipoprotein receptor activation.

    PubMed

    Park, So Youn; Lee, Jeong Hyun; Kim, Yong Ki; Kim, Chi Dae; Rhim, Byung Yong; Lee, Won Suk; Hong, Ki Whan

    2005-03-01

    This study shows cilostazol effect to prevent remnant lipoprotein particle (RLP)-induced monocyte adhesion to human umbilical vein endothelial cells (HUVECs). Upon incubation of HUVECs with RLP (50 microg/ml), adherent monocytes significantly increased by 3.3-fold with increased cell surface expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1, E-selectin, and monocyte chemoattractant protein-1 (MCP-1). Cilostazol ( approximately 1-100 microM) concentration dependently repressed these variables as did (E)3-[(4-t-butylphenyl)sulfonyl]-2-propenenitrile (BAY 11-7085) (10 microM), a specific nuclear factor-kappaB (NF-kappaB) inhibitor. Cilostazol effects were significantly antagonized by iberiotoxin (1 microM), a maxi-K channel blocker. RLP significantly increased expression of lectin-like receptor for oxidized low-density lipoprotein (LDL) (LOX-1) receptor protein. Upon transfection with antisense LOX-1 oligodeoxynucleotide (As-LOX-1), LOX-1 receptor expression was reduced, whereas HUVECs with sense LOX-1 oligodeoxynucleotide did express high LOX-1 receptor. RLP-stimulated superoxide and tumor necrosis factor-alpha levels were significantly lowered with decreased expression of VCAM-1 and MCP-1 by transfection with As-LOX-1 as did polyinosinic acid (10 microg/ml, a LOX-1 receptor inhibitor). RLP significantly degraded inhibitory kappaBalpha in the cytoplasm and activated nuclear factor-kappaB (NF-kappaB) p65 in the nucleus of HUVECs with increased luciferase activity of NF-kappaB, all of which were reversed by cilostazol (10 microM), BAY 11-7085, and polyinosinic acid. Together, cilostazol suppresses RLP-stimulated increased monocyte adhesion to HUVECs by suppression of LOX-1 receptor-coupled NF-kappaB-dependent nuclear transcription via mediation of the maxi-K channel opening.

  1. Circulating cytokines, chemokines and adhesion molecules in normal pregnancy and preeclampsia determined by multiplex suspension array

    PubMed Central

    2010-01-01

    Background Preeclampsia is a severe complication of pregnancy characterized by an excessive maternal systemic inflammatory response with activation of both the innate and adaptive arms of the immune system. Cytokines, chemokines and adhesion molecules are central to innate and adaptive immune processes. The purpose of this study was to determine circulating levels of cytokines, chemokines and adhesion molecules in normal pregnancy and preeclampsia in a comprehensive manner, and to investigate their relationship to the clinical features and laboratory parameters of the study participants, including markers of overall inflammation (C-reactive protein), endothelial activation (von Willebrand factor antigen) and endothelial injury (fibronectin), oxidative stress (malondialdehyde) and trophoblast debris (cell-free fetal DNA). Results Serum levels of interleukin (IL)-1beta, IL-1 receptor antagonist (IL-1ra), IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p40, IL-12p70, IL-18, interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, transforming growth factor (TGF)-beta1, interferon-gamma-inducible protein (IP)-10, monocyte chemotactic protein (MCP)-1, intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 were measured in 60 preeclamptic patients, 60 healthy pregnant women and 59 healthy non-pregnant women by multiplex suspension array and ELISA. In normal pregnancy, the relative abundance of circulating IL-18 over IL-12p70 and the relative deficiency of the bioactive IL-12p70 in relation to IL-12p40 might favour Th2-type immunity. Although decreased IL-1ra, TNF-alpha and MCP-1 concentrations of healthy pregnant relative to non-pregnant women reflect anti-inflammatory changes in circulating cytokine profile, their decreased serum IL-10 and increased IP-10 levels might drive pro-inflammatory responses. In addition to a shift towards Th1-type immunity (expressed by the increased IL-2/IL-4 and IFN-gamma/IL-4 ratios), circulating levels of the pro

  2. 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.

  3. Inhalation of Ultrafine Particles Alters Blood Leukocyte Expression of Adhesion Molecules in Humans

    PubMed Central

    Frampton, Mark W.; Stewart, Judith C.; Oberdörster, Günter; Morrow, Paul E.; Chalupa, David; Pietropaoli, Anthony P.; Frasier, Lauren M.; Speers, Donna M.; Cox, Christopher; Huang, Li-Shan; Utell, Mark J.

    2006-01-01

    Ultrafine particles (UFPs; aerodynamic diameter < 100 nm) may contribute to the respiratory and cardiovascular morbidity and mortality associated with particulate air pollution. We tested the hypothesis that inhalation of carbon UFPs has vascular effects in healthy and asthmatic subjects, detectable as alterations in blood leukocyte expression of adhesion molecules. Healthy subjects inhaled filtered air and freshly generated elemental carbon particles (count median diameter ~ 25 nm, geometric standard deviation ~ 1.6), for 2 hr, in three separate protocols: 10 μg/m3 at rest, 10 and 25 μg/m3 with exercise, and 50 μg/m3 with exercise. In a fourth protocol, subjects with asthma inhaled air and 10 μg/m3 UFPs with exercise. Peripheral venous blood was obtained before and at intervals after exposure, and leukocyte expression of surface markers was quantitated using multiparameter flow cytometry. In healthy subjects, particle exposure with exercise reduced expression of adhesion molecules CD54 and CD18 on monocytes and CD18 and CD49d on granulocytes. There were also concentration-related reductions in blood monocytes, basophils, and eosinophils and increased lymphocyte expression of the activation marker CD25. In subjects with asthma, exposure with exercise to 10 μg/m3 UFPs reduced expression of CD11b on monocytes and eosinophils and CD54 on granulocytes. Particle exposure also reduced the percentage of CD4+ T cells, basophils, and eosinophils. Inhalation of elemental carbon UFPs alters peripheral blood leukocyte distribution and expression of adhesion molecules, in a pattern consistent with increased retention of leukocytes in the pulmonary vascular bed. PMID:16393658

  4. Concentration of soluble adhesion molecules in cerebrospinal fluid and serum of epilepsy patients.

    PubMed

    Luo, Jing; Wang, Wei; Xi, Zhiqin; Dan, Chen; Wang, Liang; Xiao, Zheng; Wang, Xuefeng

    2014-12-01

    Mounting evidence supports the involvement of brain inflammation and the associated blood-brain barrier damage from which spontaneous and recurrent seizures originate. Detection of the soluble form of adhesion molecules (AM) has also been proven to predict outcomes in central nervous system (CNS) disorders. A recent study has shown that expression of AM in brain vessels was upregulated 24 h after kainic acid (KA) induced seizures. The aim of the present study was to investigate soluble AM levels in the cerebrospinal fluid (CSF) and serum of epilepsy patients. Paired CSF and serum samples were analyzed by sandwich enzyme-linked immunosorbent assay (ELISA) to determine the concentrations of soluble vascular cell adhesion molecule-1 (sVCAM-1) and soluble intercellular adhesion molecule-1 (sICAM-1). Increased serum concentrations of sICAM-1 were present in epileptic patients (41 localization-related of unknown etiology, 19 idiopathic generalized). Serum sICAM-1 level in drug-refractory epilepsy was elevated as compared to new diagnosis epilepsy and drug-responsive epilepsy. CSF sVCAM-1 and serum sVCAM-1 concentrations in the epilepsy group were higher as compared to the neurosis group. Moreover, CSF sVCAM-1 and serum sVCAM-1 concentrations in drug-refractory epilepsy were raised as compared to drug-responsive epilepsy and new diagnosis epilepsy. However, there were no significant differences in concentrations of CSF sICAM-1 between the epilepsy and neurosis groups. Our results suggest that sVCAM-1 and sICAM-1 could play an important role in the drug-refractory epilepsy. PMID:25001004

  5. Mediation of lung metastasis of murine melanomas by a lung-specific endothelial cell adhesion molecule.

    PubMed

    Zhu, D Z; Cheng, C F; Pauli, B U

    1991-11-01

    Organ-specific adhesion molecules expressed by vascular endothelial cells have been implicated in the arrest of blood-borne cancer cells in selective, secondary sites. A lung-specific endothelial cell adhesion molecule (Lu-ECAM-1) localized on endothelia of distinct branches of lung blood vessels has been purified by immunoaffinity chromatography from detergent extracts of lung matrix-modulated endothelial cells using monoclonal antibody (mAb) 6D3. It has a molecular mass of 90 kDa and promotes the selective attachment of lung-metastatic B16 melanoma cells. Corresponding with their metastatic performance, B16-F10 tumor cells selected for higher lung colonization bind to Lu-ECAM-1 in significantly higher numbers than their low lung metastatic counterpart B16-F0. Binding of B16-F0 and B16-F10 is reduced with mAb 6D3 to slightly lower levels than B16-F0 bound to Lu-ECAM-1. mAb 6D3 injected into C57BL/6 mice 1 hr prior to an i.v. challenge with B16-F10 causes a 90% reduction in the number of lung colonies compared with animals injected with control mAb (6D8 or 3C6). Lu-ECAM-1 neither binds nor effects metastasis of other lung-colonizing tumor cells (e.g., KLN205). Thus, site-specific metastasis of tumor cells is regulated by similar mechanisms as the homing of lymphocytes--namely, by the ability of blood-borne cancer cells to recognize and adhere to distinct endothelial cell adhesion molecules.

  6. Mediation of lung metastasis of murine melanomas by a lung-specific endothelial cell adhesion molecule.

    PubMed Central

    Zhu, D Z; Cheng, C F; Pauli, B U

    1991-01-01

    Organ-specific adhesion molecules expressed by vascular endothelial cells have been implicated in the arrest of blood-borne cancer cells in selective, secondary sites. A lung-specific endothelial cell adhesion molecule (Lu-ECAM-1) localized on endothelia of distinct branches of lung blood vessels has been purified by immunoaffinity chromatography from detergent extracts of lung matrix-modulated endothelial cells using monoclonal antibody (mAb) 6D3. It has a molecular mass of 90 kDa and promotes the selective attachment of lung-metastatic B16 melanoma cells. Corresponding with their metastatic performance, B16-F10 tumor cells selected for higher lung colonization bind to Lu-ECAM-1 in significantly higher numbers than their low lung metastatic counterpart B16-F0. Binding of B16-F0 and B16-F10 is reduced with mAb 6D3 to slightly lower levels than B16-F0 bound to Lu-ECAM-1. mAb 6D3 injected into C57BL/6 mice 1 hr prior to an i.v. challenge with B16-F10 causes a 90% reduction in the number of lung colonies compared with animals injected with control mAb (6D8 or 3C6). Lu-ECAM-1 neither binds nor effects metastasis of other lung-colonizing tumor cells (e.g., KLN205). Thus, site-specific metastasis of tumor cells is regulated by similar mechanisms as the homing of lymphocytes--namely, by the ability of blood-borne cancer cells to recognize and adhere to distinct endothelial cell adhesion molecules. Images PMID:1946371

  7. Monocyte Adhesion Molecules Expression in Patients with Chronic Hepatitis C Liver Disease

    PubMed Central

    El-Bassiouni, Nora E.I.; Mahmoud, Ola M.; El Ahwani, Eman G; Ibrahim, Raafat A.; El Bassiouny, Azza E.I.

    2013-01-01

    Background Chronic viral hepatitis is histologically characterized by predominantly periportal infiltration of mononuclear cells, including lymphocytes and monocytes/macrophages. Intralobular infiltration of these inflammatory cells is an ominous sign of deterioration and a criterion for disease activity. Objective To assess the monocyte inflammatory milieu, monocytes adhesion molecules, their endothelial receptors, cytokines and chemokines in patients with HCV induced chronic liver disease, in an attempt to clarify the role of blood monocytes in induction of inflammation and fibrogenesis in chronic hepatitis C liver disease. Subjects and Methods The current study included 60 patients with chronic liver disease categorized into 2groups: Patients chronic hepatitis C (CHC) and patients with liver cirrhosis (LC), 15 patients each; 15 healthy subjects were included as normal controls. Immunophenotype characterization was carried out by flowcytometric analysis for identification of CD11a, CD11b and CD49d monocyte surface antigen expression in different groups studied. The circulating levels of the soluble adhesion molecules (sE-selectin, sICAM-1 and sVCAM-1), cytokines (TNF-α and IL-1) and chemokines (MCP-1) were also assessed by immunoassays. Results Data demonstrated a significant increase (p<0.01) in the surface expression of CD11a on peripheral blood monocytes and in the circulating levels sE-selectins, sICAM-1, sVCAM-1 and TNF-α in both groups of patients compared to healthy subjects. Data also revealed a significant increase (p<0.01) in the surface expression of each of CD11b and CD49d on peripheral blood monocytes and in the circulating levels sICAM-1, sVCAM-1 and TNF-α in patients with LC compared to those with CHC. Moreover, data demonstrated that the increase in surface antigen expression of each CD11a (p<0.01), CD11b (p<0.05) and CD49d (p<0.01) on circulating peripheral blood monocytes is positively correlated with the increase in the circulating levels of

  8. The clinical spectrum of mutations in L1, a neuronal cell adhesion molecule

    SciTech Connect

    Fransen, E.; Vits, L.; Van Camp, G.; Willems, P.J.

    1996-07-12

    Mutations in the gene encoding the neuronal cell adhesion molecule L1 are responsible for several syndromes with clinical overlap, including X-linked hydrocephalus (XLH, HSAS), MASA (mental retardation, aphasia, shuffling gait, adducted thumbs) syndrome, complicated X-linked spastic paraplegia (SP 1), X-linked mental retardation-clasped thumb (MR-CT) syndrome, and some forms of X-linked agenesis of the corpus callosum (ACC). We review 34 L1 mutations in patients with these phenotypes. 22 refs., 3 figs., 4 tabs.

  9. Regulation of platelet biology by platelet endothelial cell adhesion molecule-1.

    PubMed

    Jones, Chris I; Moraes, Leonardo A; Gibbins, Jonathan M

    2012-01-01

    Platelet endothelial cell adhesion molecule-1 (PECAM-1), an immunoreceptor tyrosine-based inhibitory motif containing receptor, plays diverse and apparently contradictory roles in regulating the response of platelets to stimuli; inhibiting platelet response to immunoreceptor tyrosine-based activation motif and G protein-coupled receptor signalling following stimulation with collagen, adenosine diphosphate, and thrombin, as well as enhancing integrin outside-in signalling. These dual, and opposing, roles suggest an important and complex role for PECAM-1 in orchestrating platelet response to vascular damage. Indeed, during thrombus formation, the influence of PECAM-1 on the multiple signalling pathways combines leading to a relatively large inhibitory effect on thrombus formation. PMID:22035359

  10. The role of the cell adhesion molecules (integrins/cadherins) in prostate cancer.

    PubMed

    Drivalos, Alexandros; Papatsoris, Athanasios G; Chrisofos, Michael; Efstathiou, Eleni; Dimopoulos, Meletios A

    2011-01-01

    During prostate carcinogenesis the cellular adhesion molecules, i.e.; integrins and cadherins mediate aberrant interactions between glandular epithelial cells and the extracellular matrix. Several integrin α subunits are downregulated, while β subunits are up-regulated. The expression of several cadherins and catenins has specific prognostic value. There is an association between the expression of the E-cadherin/catenin complex and high grade prostate cancer. Clinical trials evaluating the efficacy of integrin antagonists are ongoing with promising results. In this article we update the role of integrins and cadherins in prostate carcinogenesis and evaluate the therapeutic potential of their manipulation.

  11. The resilient synapse: insights from genetic interference of synaptic cell adhesion molecules.

    PubMed

    Piechotta, Kerstin; Dudanova, Irina; Missler, Markus

    2006-11-01

    Synaptic cell adhesion molecules (SCAMs) are mostly membrane-anchored molecules with extracellular domains that extend into the synaptic cleft. Prototypical SCAMs interact with homologous or heterologous molecules on the surface of adjacent cells, ensuring the precise apposition of pre- and postsynaptic elements. More recent definitions of SCAMs often include molecules involved in axon pathfinding, cell recognition and synaptic differentiation events, making SCAMs functionally and molecularly a highly diverse group. In this review, we summarize the proposed in vivo functions of a large variety of SCAMs. We mainly focus on results obtained from analyses of genetic model organisms, mostly mouse knockout mutants, lacking expression of the respective candidate genes. In contrast to the substantial effect yielded by some knockouts of molecules involved in synaptic vesicle release, no SCAM mutant has been reported thus far that shows a prominently altered structure of the majority of synapses or even lacks synapses altogether. This surprising resilience of synaptic structure might be explained by a high redundancy between different SCAMs, by the assumption that the crucial molecular players in synapse structure have yet to be discovered or by a grand variability in the mechanisms of synapse formation that underlies the diversity of synapses. Whatever the final answer turns out to be, the genetic dissection of the SCAM superfamilies has led to a much better understanding of the different steps required to form, differentiate and modify a synapse.

  12. Next Generation of Targeted Molecules for Non-Hodgkin Lymphomas: Small-Molecule Inhibitors of Intracellular Targets and Signaling Pathways.

    PubMed

    Choe, Hannah; Ruan, Jia

    2016-09-15

    Advances in our understanding of the molecular pathogenesis of B-cell lymphoma have guided the development of targeted therapies that disrupt aberrant signaling pathways important for communication within lymphoma cells and for their interactions with the tumor microenvironment. This has led to unprecedented therapeutic progress, with biologic agents that have begun to transform the care of patients with lymphoma and chronic lymphocytic leukemia. This review discusses the mechanisms of action, clinical development, and emerging applications of small-molecule inhibitors that target B-cell receptor signaling pathways, B-cell lymphoma-2 inhibitors, selective inhibitors of nuclear export, and epigenetic modifiers. PMID:27633417

  13. Use of Hydration Inhibitors to Improve Bond Durability of Aluminum Adhesive Joints

    NASA Technical Reports Server (NTRS)

    Davis, G. D.; Ahearn, J. S.; Matienzo, L. J.; Venables, J. D.

    1985-01-01

    An investigation is conducted of the mechanisms by which nitrilotris methylene phosphonic acid (NTMP) and related compounds are adsorbed onto oxidized aluminum surfaces to inhibit hydration and increase the durability of adhesive bonds formed with inhibitor-treated panels. P - O - Al bonds are identified as the basis of adsorption, and it is found that water initially adsorbed onto the etched aluminum surfaces is displaced by the NTMP. The hydration of the NTMP-treated surfaces occurs in three stages, namely the reverisble physisorption of water, the slow dissolution of NTMP followed by rapid hydration of the freshly exposed Al2O3 to AlOOH and further hydration of the surface to Al(OH)3. Five properties of an ideal inhibitor are identified.

  14. Expression and role of adhesion molecule CD18 on bovine neutrophils.

    PubMed

    Nagahata, H; Nochi, H; Tamoto, K; Noda, H; Kociba, G J

    1995-01-01

    Expression of CD18 on bovine neutrophils in response to stimulation by zymosan activated serum (ZAS) and phorbol myristate acetate (PMA) and the effects of monoclonal antibodies (MAB) recognizing CD18 or bovine neutrophil surface antigens (S2G8 and S5F8G10) on adherence, chemotactic responses and phagocytosis of bovine neutrophils were evaluated. CD18 expression of neutrophils was increased after ZAS and PMA treatment by 12.2 and 54.2% respectively, and were significantly (p < 0.05, p < 0.01) different from those of untreated neutrophils. CD18 expression by neutrophils from a Holstein-Friesian heifer affected with leukocyte adhesion deficiency was within negative controls when stimulated by ZAS and PMA. Adherence, chemotactic responses, and phagocytosis were significantly decreased (p < 0.01) in neutrophils continuously treated with anti-CD18 MAB (MHM 23). Adherence was also significantly decreased in anti-CD18 pretreated neutrophils. Significant (p < 0.01) differences of chemotactic responses and phagocytosis of neutrophils were found between neutrophils pretreated and continuously treated with anti-CD18 MAB (MHM 23). Monoclonal antibodies to other surface antigens did not significantly alter neutrophil adherence, chemotaxis or phagocytosis. This study demonstrated that CD18 expression on bovine neutrophils is increased significantly by stimulation with ZAS and PMA and that the adhesion molecule CD18 plays an important role in adhesion-related functions. PMID:7704836

  15. Hyalin is a Cell Adhesion Molecule Involved in Mediating Archenteron - Blastocoel Roof Attachment

    PubMed Central

    Carroll, Edward J.; Hutchins-Carroll, Virginia; Coyle-Thompson, Catherine; Oppenheimer, Steven B.

    2008-01-01

    Summary The U. S. National Institutes of Health has designated the sea urchin embryo as a model organism because about twenty-five discoveries in this system have led to insights into the physiology of higher organisms, including humans. Hyalin is a large glycoprotein in the hyaline layer of sea urchin embryos that functions to maintain general adhesive relationships in the developing embryo. It consists of the hyalin repeat domain that has been identified in organisms as diverse as bacteria, worms, flies, mice, sea urchins and humans. Here we show, using a polyclonal antibody raised against the 11.6 S species of hyalin, that it localizes at the tip of the archenteron and on the roof of the blastocoel exactly where these two structures bond in an adhesive interaction that has been of interest for over a century. In addition, the antibody blocks the interaction between the archenteron tip and blastocoel roof. These results, in addition to other recent findings from this laboratory that will be discussed, suggest that hyalin is involved in mediating this cellular interaction. This is the first demonstration that suggests that hyalin is a specific cell adhesion molecule that may function as such in many organisms, including humans. PMID:18262230

  16. Expression of claudins, occludin, junction adhesion molecule A and zona occludens 1 in canine organs.

    PubMed

    Ahn, Changhwan; Shin, Da-Hye; Lee, Dongoh; Kang, Su-Myung; Seok, Ju-Hyung; Kang, Hee Young; Jeung, Eui-Bae

    2016-10-01

    Tight junctions are the outermost structures of intercellular junctions and are classified as transmembrane proteins. These factors form selective permeability barriers between cells, act as paracellular transporters and regulate structural and functional polarity of cells. Although tight junctions have been previously studied, comparison of the transcriptional‑translational levels of these molecules in canine organs remains to be investigated. In the present study, organ‑specific expression of the tight junction proteins, claudin, occludin, junction adhesion molecule A and zona occludens 1 was examined in the canine duodenum, lung, liver and kidney. Results of immunohistochemistry analysis demonstrated that the tight junctions were localized in intestinal villi and glands of the duodenum, bronchiolar epithelia and alveolar walls of the lung, endometrium and myometrium of the hepatocytes, and the distal tubules and glomeruli of the kidney. These results suggest that tight junctions are differently expressed in organs, and therefore may be involved in organ‑specific functions to maintain physiological homeostasis. PMID:27600198

  17. Diatomic molecules and metallic adhesion, cohesion, and chemisorption - A single binding-energy relation

    NASA Technical Reports Server (NTRS)

    Ferrante, J.; Smith, J. R.; Rose, J. H.

    1983-01-01

    Potential-energy relations involving a few parameters in simple analytic forms have been found to represent well the energetics of a wide variety of diatomic molecules. However, such two-atom potential functions are not appropriate for metals. It is well known that, in the case of metals, there exist strong volume-dependent forces which can never be expressed as pairwise interactions. The present investigation has the objective to show that, in spite of the observation concerning metals, a single binding-energy relation can be found which accurately describes diatomic molecules as well as adhesion, cohesion, and chemisorption on metals. This universality reveals a commonality between the molecular and metallic bond.

  18. Expression of claudins, occludin, junction adhesion molecule A and zona occludens 1 in canine organs

    PubMed Central

    Ahn, Changhwan; Shin, Da-Hye; Lee, Dongoh; Kang, Su-Myung; Seok, Ju-Hyung; Kang, Hee Young; Jeung, Eui-Bae

    2016-01-01

    Tight junctions are the outermost structures of intercellular junctions and are classified as transmembrane proteins. These factors form selective permeability barriers between cells, act as paracellular transporters and regulate structural and functional polarity of cells. Although tight junctions have been previously studied, comparison of the transcriptional-translational levels of these molecules in canine organs remains to be investigated. In the present study, organ-specific expression of the tight junction proteins, claudin, occludin, junction adhesion molecule A and zona occludens 1 was examined in the canine duodenum, lung, liver and kidney. Results of immunohistochemistry analysis demonstrated that the tight junctions were localized in intestinal villi and glands of the duodenum, bronchiolar epithelia and alveolar walls of the lung, endometrium and myometrium of the hepatocytes, and the distal tubules and glomeruli of the kidney. These results suggest that tight junctions are differently expressed in organs, and therefore may be involved in organ-specific functions to maintain physiological homeostasis. PMID:27600198

  19. Small-molecule inhibitors of NADPH oxidase 4.

    PubMed

    Borbély, Gábor; Szabadkai, István; Horváth, Zoltán; Markó, Péter; Varga, Zoltán; Breza, Nóra; Baska, Ferenc; Vántus, Tibor; Huszár, Mónika; Geiszt, Miklós; Hunyady, László; Buday, László; Orfi, László; Kéri, György

    2010-09-23

    NOX enzymes are the major contributors in many oxidative damage related diseases. Unfortunately, at present no specific NOX inhibitor is available. Here, we describe the discovery and development of novel NOX4 inhibitors. Compound libraries were tested in a cell-based assay as a primary screen, monitoring H2O2 production. Twenty-four compounds inhibited Nox4 activity with low-micromolar IC(50) values of which three were selected for further drug development.

  20. Structure of Reovirus σ1 in Complex with Its Receptor Junctional Adhesion Molecule-A

    PubMed Central

    Kirchner, Eva; Guglielmi, Kristen M.; Strauss, Holger M.; Dermody, Terence S.; Stehle, Thilo

    2008-01-01

    Viral attachment to specific host receptors is the first step in viral infection and serves an essential function in the selection of target cells. Mammalian reoviruses are highly useful experimental models for studies of viral pathogenesis and show promise as vectors for oncolytics and vaccines. Reoviruses engage cells by binding to carbohydrates and the immunoglobulin superfamily member, junctional adhesion molecule-A (JAM-A). JAM-A exists at the cell surface as a homodimer formed by extensive contacts between its N-terminal immunoglobulin-like domains. We report the crystal structure of reovirus attachment protein σ1 in complex with a soluble form of JAM-A. The σ1 protein disrupts the JAM-A dimer, engaging a single JAM-A molecule via virtually the same interface that is used for JAM-A homodimerization. Thus, reovirus takes advantage of the adhesive nature of an immunoglobulin-superfamily receptor by usurping the ligand-binding site of this molecule to attach to the cell surface. The dissociation constant (KD) of the interaction between σ1 and JAM-A is 1,000-fold lower than that of the homophilic interaction between JAM-A molecules, indicating that JAM-A strongly prefers σ1 as a ligand. Analysis of reovirus mutants engineered by plasmid-based reverse genetics revealed residues in σ1 required for binding to JAM-A and infectivity of cultured cells. These studies define biophysical mechanisms of reovirus cell attachment and provide a platform for manipulating reovirus tropism to enhance vector targeting. PMID:19079583

  1. Ankyrin-binding activity of nervous system cell adhesion molecules expressed in adult brain.

    PubMed

    Davis, J Q; Bennett, V

    1993-01-01

    A family of ankyrin-binding glycoproteins have been identified in adult rat brain that include alternatively spliced products of the same pre-mRNA. A composite sequence of ankyrin-binding glycoprotein (ABGP) shares 72% amino acid sequence identity with chicken neurofascin, a membrane-spanning neural cell adhesion molecule in the Ig super-family expressed in embryonic brain. ABGP polypeptides and ankyrin associate as pure proteins in a 1:1 molar stoichiometry at a site located in the predicted cytoplasmic domain. ABGP polypeptides are expressed late in postnatal development to approximately the same levels as ankyrin, and comprise a significant fraction of brain membrane proteins. Immunofluorescence studies have shown that ABGP polypeptides are co-localized with ankyrinB. Major differences in developmental expression have been reported for neurofascin in embryos compared with the late postnatal expression of ABGP, suggesting that ABGP and neurofascin represent products of gene duplication events that have subsequently evolved in parallel with distinct roles. Predicted cytoplasmic domains of rat ABGP and chicken neurofascin are nearly identical to each other and closely related to a group of nervous system cell adhesion molecules with variable extracellular domains, including L1, Nr-CAM and Ng-CAM of vertebrates, and neuroglian of Drosophila. A hypothesis to be evaluated is that ankyrin-binding activity is shared by all of these proteins.

  2. Effect of Cell Adhesion Molecule 1 Expression on Intracellular Granule Movement in Pancreatic α Cells.

    PubMed

    Yokawa, Satoru; Furuno, Tadahide; Suzuki, Takahiro; Inoh, Yoshikazu; Suzuki, Ryo; Hirashima, Naohide

    2016-09-01

    Although glucagon secreted from pancreatic α cells plays a role in increasing glucose concentrations in serum, the mechanism regulating glucagon secretion from α cells remains unclear. Cell adhesion molecule 1 (CADM1), identified as an adhesion molecule in α cells, has been reported not only to communicate among α cells and between nerve fibers, but also to prevent excessive glucagon secretion from α cells. Here, we investigated the effect of CADM1 expression on the movement of intracellular secretory granules in α cells because the granule transport is an important step in secretion. Spinning disk microscopic analysis showed that granules moved at a mean velocity of 0.236 ± 0.010 μm/s in the mouse α cell line αTC6 that expressed CADM1 endogenously. The mean velocity was significantly decreased in CADM1-knockdown (KD) cells (mean velocity: 0.190 ± 0.016 μm/s). The velocity of granule movement decreased greatly in αTC6 cells treated with the microtubule-depolymerizing reagent nocodazole, but not in αTC6 cells treated with the actin-depolymerizing reagent cytochalasin D. No difference in the mean velocity was observed between αTC6 and CADM1-KD cells treated with nocodazole. These results suggest that intracellular granules in pancreatic α cells move along the microtubule network, and that CADM1 influences their velocity. PMID:27262873

  3. Decreased pulmonary inflammation after ethanol exposure and burn injury in intercellular adhesion molecule-1 knockout mice.

    PubMed

    Bird, Melanie D; Morgan, Michelle O; Ramirez, Luis; Yong, Sherri; Kovacs, Elizabeth J

    2010-01-01

    Clinical and laboratory evidence suggests that alcohol consumption dysregulates immune function. Burn patients who consume alcohol before their injuries demonstrate higher rates of morbidity and mortality, including acute respiratory distress syndrome, than patients without alcohol at the time of injury. Our laboratory observed higher levels of proinflammatory cytokines and leukocyte infiltration in the lungs of mice after ethanol exposure and burn injury than with either insult alone. To understand the mechanism of the increased pulmonary inflammatory response in mice treated with ethanol and burn injury, we investigated the role of intercellular adhesion molecule (ICAM)-1. Wild-type and ICAM-1 knockout (KO) mice were treated with vehicle or ethanol and subsequently given a sham or burn injury. Twenty-four hours postinjury, lungs were harvested and analyzed for indices of inflammation. Higher numbers of neutrophils were observed in the lungs of wild-type mice after burn and burn with ethanol treatment. This increase in pulmonary inflammatory cell accumulation was significantly lower in the KO mice. In addition, levels of KC, interleukin-1beta, and interleukin-6 in the lung were decreased in the ICAM-1 KO mice after ethanol exposure and burn injury. Interestingly, no differences were observed in serum or lung tissue content of soluble ICAM-1 24 hours postinjury. These data suggest that upregulation of adhesion molecules such as ICAM-1 on the vascular endothelium may play a critical role in the excessive inflammation seen after ethanol exposure and burn injury.

  4. The immunohistochemical expression of CD24 and CD171 adhesion molecules in borderline ovarian tumors.

    PubMed

    Moulla, Alexandra; Miliaras, Dimosthenis; Sioga, Antonia; Kaidoglou, Aikaterini; Economou, Louisa

    2013-10-01

    CD24 and CD171 are cell adhesion proteins, which have been shown to be overexpressed in several carcinomas and to be associated with a poor clinical outcome. Our aim was to determine the expression of these two adhesion molecules in ovarian borderline neoplasms. We investigated 50 ovarian borderline tumors (serous, mucinous and endometrioid) as well as 29 benign cystadenomas and 25 carcinomas, which were used as controls. Paraffin sections were stained immunohistochemically for CD24 and CD171, and their expression was recorded in a semi-quantitative manner. In normal epithelium and benign ovarian cystadenomas both the CD24 and CD171 expression was negative to low, while their expression was significantly increased in borderline and malignant ovarian tumors. High-grade carcinomas, and carcinomas with metastases to the omentum presented considerably higher CD24 expression than low-grade carcinomas, and carcinomas without metastases. In addition, a few borderline and many malignant tumors presented cytoplasmic CD24 immunoreactivity, whereas all benign and most borderline tumors showed apical localization of this molecule. In conclusion, borderline tumors and carcinomas of the ovary present increased expression of CD24 and CD171 in relation to their benign counterparts, as is the case in malignant tumors of other organs. Change of staining pattern of CD24 (apical to cytoplasmic) apparently relates to a more aggressive phenotype. PMID:24166603

  5. Lutheran/basal cell adhesion molecule accelerates progression of crescentic glomerulonephritis in mice

    PubMed Central

    Huang, Jin; Filipe, Anne; Rahuel, Cécile; Bonnin, Philippe; Mesnard, Laurent; Guérin, Coralie; Wang, Yu; Le Van Kim, Caroline; Colin, Yves; Tharaux, Pierre-Louis

    2014-01-01

    Migration of circulating leukocytes from the vasculature into the surrounding tissue is an important component of the inflammatory response. Among the cell surface molecules identified as contributing to leukocyte extravasation is VCAM-1, expressed on activated vascular endothelium, which participates in all stages of leukocyte–endothelial interaction by binding to leukocyte surface expressed integrin VLA-4. However, not all VLA-4-mediated events can be linked to VCAM-1. A novel interaction between VLA-4 and endothelial Lutheran (Lu) blood group antigens and basal cell adhesion molecule (BCAM) proteins has been recently shown, suggesting that Lu/BCAM may have a role in leukocyte recruitments in inflamed tissues. Here, we assessed the participation of Lu/BCAM in the immunopathogenesis of crescentic glomerulonephritis. High expression of Lu/BCAM in glomeruli of mice with rapidly progressive glomerulonephritis suggests a potential role for the local expression of Lu/BCAM in nephritogenic recruitment of leukocytes. Genetic deficiency of Lu/BCAM attenuated glomerular accumulation of T cells and macrophages, crescent formation, and proteinuria, correlating with reduced fibrin and platelet deposition in glomeruli. Furthermore, we found a pro-adhesive interaction between human monocyte α4β1 integrin and Lu/BCAM proteins. Thus, Lu/BCAM may have a critical role in facilitating the accumulation of monocytes and macrophages, thereby exacerbating renal injury. PMID:24429403

  6. Neural cell adhesion molecule modulates mesenchymal stromal cell migration via activation of MAPK/ERK signaling.

    PubMed

    Shi, Yu; Xia, Yin-Yan; Wang, Lei; Liu, Rui; Khoo, King-Shung; Feng, Zhi-Wei

    2012-10-15

    Mesenchymal Stromal Cells (MSCs) represent promising tools for cellular therapy owing to their multipotentiality and ability to localize to injured, inflamed sites and tumor. Various approaches to manipulate expression of MSC surface markers, including adhesion molecules and chemokine receptors, have been explored to enhance homing of MSCs. Recently, Neural Cell Adhesion Molecule (NCAM) has been found to be expressed on MSCs yet its function remains largely elusive. Herein, we show that bone marrow-derived MSCs from NCAM deficient mice exhibit defective migratory ability and significantly impaired adipogenic and osteogenic differentiation potential. We further explore the mechanism governing NCAM mediated migration of MSCs by showing the interplay between NCAM and Fibroblast Growth Factor Receptor (FGFR) induces activation of MAPK/ERK signaling, thereby the migration of MSCs. In addition, re-expression of NCAM180, but not NCAM140, could restore the defective MAPK/ERK signaling thereby the migration of NCAM deficient MSCs. Finally, we demonstrate that NCAM180 expression level could be manipulated by pro-inflammatory cytokine Tumor Necrosis Factor (TNF)-α treatment. Overall, our data reveal the vital function of NCAM in MSCs migration and differentiation thus raising the possibility of manipulating NCAM expression to enhance homing and therapeutic potential of MSCs in cellular therapy.

  7. Human cell adhesion molecules: annotated functional subtypes and overrepresentation of addiction-associated genes

    PubMed Central

    Zhong, Xiaoming; Drgonova, Jana; Li, Chuan-Yun; Uhl, George R.

    2015-01-01

    Human cell adhesion molecules (CAMs) are essential both for a) proper development, modulation and maintenance of interactions between cells and for b) cell-to-cell (and matrix-to-cell) communication about these interactions. CAMs are thus key to proper development and plasticity of organs and tissues that include the brain. Despite recognition of the existence of these dual CAM roles and appreciation of the differential functional significance of these roles, there have been surprisingly few systematic studies that have carefully enumerated the universe of CAMs, identified the preferred roles for specific CAMs in distinct types of cellular connections and communication, or related these issues to specific brain disorders or brain circuits. In this paper, we substantially update and review the set of human genes that are likely to encode CAMs based on searches of databases, literature reviews and annotations. We describe the likely CAMs and the functional CAM subclasses into which they fall. These include “iCAMs”, whose contacts largely mediate cell to cell communication, those involved in focal adhesions, CAM genes whose products are preferentially involved with stereotyped and morphologically-identifiable connections between cells (adherens junctions, gap junctions) and smaller numbers of genes in other classes. We discuss a novel proposed mechanism involving selective anchoring of the constituents of iCAM-containing lipid rafts in zones of close neuronal apposition to membranes expressing binding partners of these iCAMs. CAM data from genetic and genomic studies of addiction in humans and mouse models provide examples of the ways in which CAM variation is likely to contribute to a specific brain-based disorder. We discuss how differences in CAM splicing mediated by differences in the addiction-associated splicing regulator RBFOX1/A2BP1 could enrich this picture. CAM expression in dopamine neurons provides one of the ways in which variations in cell adhesion

  8. Targeting Mycobacterium tuberculosis topoisomerase I by small-molecule inhibitors.

    PubMed

    Godbole, Adwait Anand; Ahmed, Wareed; Bhat, Rajeshwari Subray; Bradley, Erin K; Ekins, Sean; Nagaraja, Valakunja

    2015-03-01

    We describe inhibition of Mycobacterium tuberculosis topoisomerase I (MttopoI), an essential mycobacterial enzyme, by two related compounds, imipramine and norclomipramine, of which imipramine is clinically used as an antidepressant. These molecules showed growth inhibition of both Mycobacterium smegmatis and M. tuberculosis cells. The mechanism of action of these two molecules was investigated by analyzing the individual steps of the topoisomerase I (topoI) reaction cycle. The compounds stimulated cleavage, thereby perturbing the cleavage-religation equilibrium. Consequently, these molecules inhibited the growth of the cells overexpressing topoI at a low MIC. Docking of the molecules on the MttopoI model suggested that they bind near the metal binding site of the enzyme. The DNA relaxation activity of the metal binding mutants harboring mutations in the DxDxE motif was differentially affected by the molecules, suggesting that the metal coordinating residues contribute to the interaction of the enzyme with the drug. Taken together, the results highlight the potential of these small molecules, which poison the M. tuberculosis and M. smegmatis topoisomerase I, as leads for the development of improved molecules to combat mycobacterial infections. Moreover, targeting metal coordination in topoisomerases might be a general strategy to develop new lead molecules.

  9. IL-18 regulates IL-1β-dependent hepatic melanoma metastasis via vascular cell adhesion molecule-1

    PubMed Central

    Vidal-Vanaclocha, Fernando; Fantuzzi, Giamila; Mendoza, Lorea; Fuentes, Angela M.; Anasagasti, Miren J.; Martín, Javier; Carrascal, Teresa; Walsh, Patrick; Reznikov, Leonid L.; Kim, Soo-Hyun; Novick, Daniela; Rubinstein, Menachem; Dinarello, Charles A.

    2000-01-01

    Proinflammatory cytokines, including IL-1β and tumor necrosis factor-α (TNF-α), promote cancer cell adhesion and liver metastases by up-regulating the expression of vascular cell adhesion molecule-1 (VCAM-1) on hepatic sinusoidal endothelium (HSE). In this study, hepatic metastasis after intrasplenically injected mouse B16 melanoma (B16M) cells was reduced 84–95% in mice with null mutations for either IL-1β or the IL-1β-converting enzyme (ICE, caspase-1) compared with wild-type mice. On day 12, 47% of wild-type mice were dead compared with 19% of either IL-1β or ICE-deficient mice. In vitro, conditioned medium from B16M cells (B16M-CM) induced the release of TNF-α and IL-1β from cultures of primary murine HSE. The effect of B16M-CM on HSE resulted in increased numbers of B16M cells adhering to HSE, which was completely abrogated by a specific inhibitor of ICE, anti-IL-18 or IL-18-binding protein. Exogenous IL-18 added to HSE also increased the number of adhering melanoma cells; however, this was not affected by IL-1 receptor blockade or TNF neutralization but rather by anti-VCAM-1. These results demonstrate a role for IL-1β and IL-18 in the development of hepatic metastases of B16M in vivo. In vitro, soluble products from B16M cells stimulate HSE to sequentially release TNF-α, IL-1β, and IL-18. The IL-18 cytokine increases expression of VCAM-1 and the adherence of melanoma cells. PMID:10639148

  10. Large negatively charged organic host molecules as inhibitors of endonuclease enzymes.

    PubMed

    Tauran, Yannick; Anjard, Christophe; Kim, Beomjoon; Rhimi, Moez; Coleman, Anthony W

    2014-10-01

    Three large negatively charged organic host molecules; β-cyclodextrin sulphate, para-sulphonato-calix[6]arene and para-sulphonato-calix[8]arene have been shown to be effective inhibitors of endonuclease in the low micromolar range, additionally para-sulphonato-calix[8]arene is a partial inhibitor of rhDNase I.

  11. Modulation of tight junction barrier function by outer membrane proteins of enteropathogenic Escherichia coli: role of F-actin and junctional adhesion molecule-1.

    PubMed

    Puthenedam, Manjula; Williams, Peter H; Lakshmi, B S; Balakrishnan, Arun

    2007-08-01

    Enteropathogenic Escherichia coli (EPEC) is a major cause of infantile diarrhea. In this work we investigated the effect of outer membrane proteins (OMP) of EPEC on barrier integrity and the role of actin, junctional adhesion molecule (JAM) and signaling pathways contributing to these changes. Barrier function was assessed by transepithelial electrical resistance (TER). OMP of wild type EPEC, eaeA and maltoporin mutants decreased TER levels of Caco-2 cells. The OMP of espB mutant was deficient in decreasing TER of Caco-2 cells. The proteinase K-digested wild type OMP and EAF mutant OMP did not cause any change in barrier function. Our previous studies have demonstrated that EPEC OMP induced changes in cadherin junctions of Caco-2 cells. Immunofluorescence revealed disruption in actin cytoskeleton by EPEC OMP. However, no change in expression of junctional adhesion molecule-1 was observed. NF-kappaB inhibitor slightly blocked the decrease in TER and protected against actin disruption while ERK1/2 inhibitor had no effect in blocking these changes. In conclusion, our data suggest that the OMP of EPEC alter intestinal barrier function by disrupting actin cytoskeleton and signaling pathways like NF-kappaB may have a role in regulating barrier changes.

  12. Adsorption Mechanism of Inhibitor and Guest Molecules on the Surface of Gas Hydrates.

    PubMed

    Yagasaki, Takuma; Matsumoto, Masakazu; Tanaka, Hideki

    2015-09-23

    The adsorption of guest and kinetic inhibitor molecules on the surface of methane hydrate is investigated by using molecular dynamics simulations. We calculate the free energy profile for transferring a solute molecule from bulk water to the hydrate surface for various molecules. Spherical solutes with a diameter of ∼0.5 nm are significantly stabilized at the hydrate surface, whereas smaller and larger solutes exhibit lower adsorption affinity than the solutes of intermediate size. The range of the attractive force is subnanoscale, implying that this force has no effect on the macroscopic mass transfer of guest molecules in crystal growth processes of gas hydrates. We also examine the adsorption mechanism of a kinetic hydrate inhibitor. It is found that a monomer of the kinetic hydrate inhibitor is strongly adsorbed on the hydrate surface. However, the hydrogen bonding between the amide group of the inhibitor and water molecules on the hydrate surface, which was believed to be the driving force for the adsorption, makes no contribution to the adsorption affinity. The preferential adsorption of both the kinetic inhibitor and the spherical molecules to the surface is mainly due to the entropic stabilization arising from the presence of cavities at the hydrate surface. The dependence of surface affinity on the size of adsorbed molecules is also explained by this mechanism.

  13. Soluble Melanoma Cell Adhesion Molecule (sMCAM/sCD146) Promotes Angiogenic Effects on Endothelial Progenitor Cells through Angiomotin*

    PubMed Central

    Stalin, Jimmy; Harhouri, Karim; Hubert, Lucas; Subrini, Caroline; Lafitte, Daniel; Lissitzky, Jean-Claude; Elganfoud, Nadia; Robert, Stéphane; Foucault-Bertaud, Alexandrine; Kaspi, Elise; Sabatier, Florence; Aurrand-Lions, Michel; Bardin, Nathalie; Holmgren, Lars; Dignat-George, Françoise; Blot-Chabaud, Marcel

    2013-01-01

    The melanoma cell adhesion molecule (CD146) contains a circulating proteolytic variant (sCD146), which is involved in inflammation and angiogenesis. Its circulating level is modulated in different pathologies, but its intracellular transduction pathways are still largely unknown. Using peptide pulldown and mass spectrometry, we identified angiomotin as a sCD146-associated protein in endothelial progenitor cells (EPC). Interaction between angiomotin and sCD146 was confirmed by enzyme-linked immunosorbent assay (ELISA), homogeneous time-resolved fluorescence, and binding of sCD146 on both immobilized recombinant angiomotin and angiomotin-transfected cells. Silencing angiomotin in EPC inhibited sCD146 angiogenic effects, i.e. EPC migration, proliferation, and capacity to form capillary-like structures in Matrigel. In addition, sCD146 effects were inhibited by the angiomotin inhibitor angiostatin and competition with recombinant angiomotin. Finally, binding of sCD146 on angiomotin triggered the activation of several transduction pathways that were identified by antibody array. These results delineate a novel signaling pathway where sCD146 binds to angiomotin to stimulate a proangiogenic response. This result is important to find novel target cells of sCD146 and for the development of therapeutic strategies based on EPC in the treatment of ischemic diseases. PMID:23389031

  14. Adhesion molecule expression in Graves' thyroid glands; potential relevance of granule membrane protein (GMP-140) and intercellular adhesion molecule-1 (ICAM-1) in the homing and antigen presentation processes.

    PubMed Central

    Miyazaki, A; Mirakian, R; Bottazzo, G F

    1992-01-01

    To assess the potential role of adhesion molecules in the pathogenesis of Graves' disease, we examined the expression of several of these adhesion molecules, including intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule (VCAM-1) and granule membrane protein-140 (GMP-140), in sections of Graves' thyroid glands and control thyroids, using immunohistochemical techniques. Up-regulated expression of GMP-140 was frequently observed on endothelial cells (EC) of post-capilliary venules in all Graves' thyroids examined, compared with an occasional weak staining on EC control glands. Some capillary EC around thyroid follicles (perifollicular EC) were strongly positive for GMP-140 in the Graves' thyroids in contrast to a negative staining on the same structures in the control glands. In addition, there was a correlation between the reactivity and frequency of GMP-140 expression on EC and the severity of mononuclear cell (MNC) infiltration in the Graves' thyroids. The expression of ICAM-1 was up-regulated on perifollicular EC and EC of small venules in some thyroids of both Graves' and control groups. Conversely, no significant expression was observed on any type of EC for both endothelial-leucocyte adhesion molecule-1 (ELAM-1) and VCAM-1. However, dendritic-like cells, present within lymphocytic infiltrates, were positive for VCAM-1 in most of the Graves' thyroids examined, especially in those with a severe lymphocytic infiltration. Thyrocytes were constantly negative for the expression of all four adhesion molecules investigated. These data suggest that GMP-140, as well as ICAM-1, could play an important role in the initiation of MNC infiltration in Graves' disease. ELAM-1 and VCAM-1 appear not to be relevant for the migration of MNC from the blood vessels into the target gland, although VCAM-1 expression on dendritic-like cells might play an additively tissue-selective role in autoantigen presentation and subsequent elicitation of autoimmune

  15. L1 cell adhesion molecule induces melanoma cell motility by activation of mitogen-activated protein kinase pathways.

    PubMed

    Yi, Young-Su; Baek, Kwang-Soo; Cho, Jae Youl

    2014-06-01

    L1 cell adhesion molecule (L1CAM) is highly expressed in various types of cancer cells and has been implicated in the control of cell proliferation and motility. Recently, L1CAM was reported to induce the motility of melanoma cells, but the mechanism of this induction remains poorly understood. In this study, we investigated the molecular mechanisms by which L1CAM induces the motility of melanoma cells. Unlike other types of cancer cells, B16F10 melanoma cells highly expressed L1CAM at both the RNA and protein levels, and the expression of L1CAM induced AP-1 activity. In accordance to AP-1 activation, MAPK signaling pathways were activated by L1CAM. Inhibition of L1CAM expression by L1CAM-specific siRNA suppressed the activation of MAPKs such as ERK and p38. However, no significant change was observed in JNK activation. As expected, upstream MAP2K, MKK3/6, MAP3K, and TAK1 were also deactivated by the inhibition of L1CAM expression. L1CAM induced the motility of B16F10 cells. Inhibition of L1CAM expression suppressed migration and invasion of B16F10 cells, but no suppressive effect was observed on their proliferation and anti-apoptotic resistance. Treatment of B16F10 cells with U0126, an ERK inhibitor, or SB203580, a p38 inhibitor, suppressed the migration and invasion abilities of B16F10 cells. Taken together, our results suggest that L1CAM induces the motility of B16F10 melanoma cells via the activation of MAPK pathways. This finding provides a more detailed molecular mechanism of L1CAM-mediated induction of melanoma cell motility. PMID:24974583

  16. Sphingosine 1-phosphate induces platelet/endothelial cell adhesion molecule-1 phosphorylation in human endothelial cells through cSrc and Fyn.

    PubMed

    Huang, Yu-Ting; Chen, Shee-Uan; Chou, Chia-Hong; Lee, Hsinyu

    2008-08-01

    Sphingosine 1-phosphate (S1P) is a multifunctional phospholipid which acts through a specific family of G protein-coupled receptors. Platelet/endothelial cell adhesion molecule-1 (PECAM-1) form trans-homophilic binding at lateral cell border. Upon stimulation, its cytoplasmic tyrosine residues could be phosphorylated and interact with various downstream signaling molecules. In this study, we demonstrated that S1P induced PECAM-1 tyrosine phosphorylation in human umbilical cord vein cells (HUVECs). By pharmacological inhibitors, it was suggested that G(i) and Src family kinases were involved in PECAM-1 phosphorylation. Moreover, cSrc and Fyn siRNA significantly suppressed S1P-induced PECAM-1 phosphorylation. These results suggested that S1P-induced PECAM-1 phosphorylation through G(i) and subsequent cSrc and Fyn. Our findings provide further understanding of S1P and PECAM-1 signaling as well as their functions in endothelial cells. PMID:18502612

  17. Determination of the inhibitor dissociation constant of an individual unmodified enzyme molecule in free solution.

    PubMed

    Crawford, Jeremie J; Hollett, Joshua W; Craig, Douglas B

    2016-08-01

    Single enzyme molecule assays on E. coli β-galactosidase were performed using a capillary electrophoresis-based method. Three types of assays were performed. The catalytic rate of 20 individual molecules was assayed in duplicate in the presence of 50 μM substrate. The ratio of rates for the second incubation relative to the first was 0.96 ± 0.03, showing the reproducibility of the method. In the second assay, the rates were determined in the absence and presence of 210 μM L-ribose, a competitive inhibitor. The ratio of the rate in the presence of inhibitor to that in its absence for 19 individual molecules was 0.44 ± 0.23. This large relative standard deviation suggests that each individual enzyme molecule was affected to a different extent by the presence of the inhibitor, which is consistent with KI being heterogeneous. To estimate KI for individual molecules, a third assay was performed. Each molecule was incubated in the presence of 30 and 50 μM substrate and then in the presence of 50 μM substrate plus 210 μM inhibitor. Comparison of the rates in the two substrate concentrations allowed for the determination of the individual Km of each molecule. From this value and the difference in rates in the presence and absence of inhibitor, the individual molecule KI values were determined. This value was found to differ between individual molecules and was found to increase with an increase in Km . Modeling showed that a heterogeneity in KI results in an alteration in the Michaelis-Menten curve for a population of enzymes in the presence of a competitive inhibitor. PMID:27271375

  18. Synchronous elevation of soluble intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) correlates with gastric cancer progression.

    PubMed

    Yoo, N C; Chung, H C; Chung, H C; Park, J O; Rha, S Y; Kim, J H; Roh, J K; Min, J S; Kim, B S; Noh, S H

    1998-02-01

    Soluble forms of ICAM-1 (sICAM-1) and VCAM-1 (sVCAM-1) have been reported from the supernatant of cytokine-activated endothelial cells, cancer cells and from sera of cancer patients. We measured sICAM-1 and sVCAM-1 from the serum of 20 healthy volunteers and 142 gastric cancer patients by ELISA assay. Ninety-five patients were operable and 47 patients were in-operable at the time of this study. Particularly in the 28 operable patients, we sampled both portal and peripheral blood simultaneously and measured the levels of the soluble forms of cell adhesion molecules (sCAMs). The sCAMs level and sero-positivity rate increased with cancer progression in order of the healthy controls, operable patients, and inoperable patients. In in-operable cancer, the sICAM-1 level increased more with liver metastasis. sICAM-1 and sVCAM-1 did not correlate with each other in either portal or peripheral blood. A total of 58.3% of patients with liver metastasis and 22.9% of patients without liver metastasis showed synchronous expression of both sCAMs (p = 0.03). Synchronous sero-positivity of sCAMs and alpha FP was higher with liver metastasis (p = 0.01). The median overall survival duration which co-expressed both sCAMs was 9 months. This showed a significant difference compared with the sICAMs non-expressing group, where the median survival was not reached until 24 months follow-up (p = 0.002). The synchronous expression of sCAMs was an independent risk factor in gastric cancer patients. We raise the possibility that synchronous sICAM-1 and sVCAM-1 elevation may be a useful monitor to determine tumor burden in gastric cancer.

  19. Differing roles for B7 and intercellular adhesion molecule-1 in negative selection of thymocytes

    PubMed Central

    1996-01-01

    To ensure self tolerance, immature thymocytes with high binding affinity for self peptides linked to major histocompatibility complex (MHC) molecules are eliminated in situ via apoptosis (negative selection). The roles of two costimulatory molecules, B7-1 and intercellular adhesion molecule-1 (ICAM-1), in negative selection was examined by studying apoptosis of T cell receptor transgenic CD4+8+ thymocytes cultured with specific peptides presented by MHC class I- transfected Drosophila cells. When coexpressed on these cells, B7-1 and ICAM-1 act synergistically and cause strong class 1-restricted negative selection of thymocytes. When expressed separately, however, B7-1 and ICAM-1 display opposite functions: negative selection is augmented by B7-1, but is inhibited by ICAM-1. It is notable that B7-1 is expressed selectively in the thymic medulla, whereas ICAM-1 is expressed throughout the thymus. Because of this distribution, the differing functions of B7-1 and ICAM-1 may dictate the sites of positive and negative selection. Thus, in the cortex, the presence of ICAM-1, but not B7-1, on the cortical epithelium may preclude or reduce negative selection and thereby promote positive selection. Conversely, the combined expression of B7-1 and ICAM-1 may define the medulla as the principal site of negative selection. PMID:8760806

  20. Induction of intercellular adhesion molecule-1 on human brain endothelial cells by HIV-1 gp120: role of CD4 and chemokine coreceptors.

    PubMed

    Stins, Monique F; Pearce, Donna; Di Cello, Francescopaolo; Erdreich-Epstein, Anat; Pardo, Carlos A; Sik Kim, Kwang

    2003-12-01

    Central nervous system dysfunction is commonly observed in children with HIV-1 infection, but the mechanisms whereby HIV-1 causes encephalopathy are not completely understood. We have previously shown that human brain microvascular endothelial cells (HBMEC) from children are responsive to gp120 derived from X4 HIV-1 by increasing expression of intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule-1. However, the mechanisms involved in gp120-mediated up-regulation of cell adhesion molecule expression is unclear. In the present study, we found that gp120 derived from both X4 and R5 HIV-1 induced increased expression of ICAM-1 on HBMEC, but the degree of this up-regulation differed among the various HBMEC isolates. The up-regulation of ICAM-1 was inhibited by anti-CD4 antibodies as well as by specific antibodies directed against chemokine receptors and small-molecule coreceptor inhibitors. Anti-CD4 antibodies inhibited the increase in ICAM-1 expression mediated by gp120 derived from X4 and R5 HIV-1, whereas antibodies against chemokine receptors displayed a differential inhibition depending on the source of gp120. Both X4 and R5 gp120-induced ICAM-1 expression was sensitive to pertussis toxin and involved the nuclear factor-kB pathway. These findings indicate a direct involvement of CD4 and a differential involvement of chemokine receptors in the activation of pediatric HBMEC by X4 and R5 gp120. The activation of brain endothelium of children by HIV-1 protein gp120 by way of CD4 and chemokine receptors may have implications for the pathogenesis of HIV-1 encephalopathy in the pediatric population.

  1. Novel 1H-imidazol-2-amine derivatives as potent and orally active vascular adhesion protein-1 (VAP-1) inhibitors for diabetic macular edema treatment.

    PubMed

    Inoue, Takayuki; Morita, Masataka; Tojo, Takashi; Nagashima, Akira; Moritomo, Ayako; Miyake, Hiroshi

    2013-07-01

    Novel thiazole derivatives were synthesized and evaluated as vascular adhesion protein-1 (VAP-1) inhibitors. Although we previously identified a compound (2) with potent VAP-1 inhibitory activity in rats, the human activity was relatively weak. Here, to improve the human VAP-1 inhibitory activity of compound 2, we first evaluated the structure-activity relationships of guanidine bioisosteres as simple small molecules and identified a 1H-benzimidazol-2-amine (5) with potent activity compared to phenylguanidine (1). Based on the structure of compound 5, we synthesized a highly potent VAP-1 inhibitor (37b; human IC50=0.019 μM, rat IC50=0.0051 μM). Orally administered compound 37b also markedly inhibited ocular permeability in streptozotocin-induced diabetic rats after oral administration, suggesting it is a promising compound for the treatment of diabetic macular edema.

  2. Human cell adhesion molecules: annotated functional subtypes and overrepresentation of addiction-associated genes.

    PubMed

    Zhong, Xiaoming; Drgonova, Jana; Li, Chuan-Yun; Uhl, George R

    2015-09-01

    Human cell adhesion molecules (CAMs) are essential for proper development, modulation, and maintenance of interactions between cells and cell-to-cell (and matrix-to-cell) communication about these interactions. Despite the differential functional significance of these roles, there have been surprisingly few systematic studies to enumerate the universe of CAMs and identify specific CAMs in distinct functions. In this paper, we update and review the set of human genes likely to encode CAMs with searches of databases, literature reviews, and annotations. We describe likely CAMs and functional subclasses, including CAMs that have a primary function in information exchange (iCAMs), CAMs involved in focal adhesions, CAM gene products that are preferentially involved with stereotyped and morphologically identifiable connections between cells (e.g., adherens junctions, gap junctions), and smaller numbers of CAM genes in other classes. We discuss a novel proposed mechanism involving selective anchoring of the constituents of iCAM-containing lipid rafts in zones of close neuronal apposition to membranes expressing iCAM binding partners. We also discuss data from genetic and genomic studies of addiction in humans and mouse models to highlight the ways in which CAM variation may contribute to a specific brain-based disorder such as addiction. Specific examples include changes in CAM mRNA splicing mediated by differences in the addiction-associated splicing regulator RBFOX1/A2BP1 and CAM expression in dopamine neurons. PMID:25988664

  3. Neural cell adhesion molecule (NCAM) marks adult myogenic cells committed to differentiation

    SciTech Connect

    Capkovic, Katie L.; Stevenson, Severin; Johnson, Marc C.; Thelen, Jay J.; Cornelison, D.D.W.

    2008-04-15

    Although recent advances in broad-scale gene expression analysis have dramatically increased our knowledge of the repertoire of mRNAs present in multiple cell types, it has become increasingly clear that examination of the expression, localization, and associations of the encoded proteins will be critical for determining their functional significance. In particular, many signaling receptors, transducers, and effectors have been proposed to act in higher-order complexes associated with physically distinct areas of the plasma membrane. Adult muscle stem cells (satellite cells) must, upon injury, respond appropriately to a wide range of extracellular stimuli: the role of such signaling scaffolds is therefore a potentially important area of inquiry. To address this question, we first isolated detergent-resistant membrane fractions from primary satellite cells, then analyzed their component proteins using liquid chromatography-tandem mass spectrometry. Transmembrane and juxtamembrane components of adhesion-mediated signaling pathways made up the largest group of identified proteins; in particular, neural cell adhesion molecule (NCAM), a multifunctional cell-surface protein that has previously been associated with muscle regeneration, was significant. Immunohistochemical analysis revealed that not only is NCAM localized to discrete areas of the plasma membrane, it is also a very early marker of commitment to terminal differentiation. Using flow cytometry, we have sorted physically homogeneous myogenic cultures into proliferating and differentiating fractions based solely upon NCAM expression.

  4. A functional integrin ligand on the surface of platelets: intercellular adhesion molecule-2.

    PubMed Central

    Diacovo, T G; deFougerolles, A R; Bainton, D F; Springer, T A

    1994-01-01

    Activated platelets express P-selectin and release leukocyte chemoattractants; however, they have not been known to express integrin ligands important in the stabilization of leukocyte interactions with the vasculature. We now demonstrate the presence of intercellular adhesion molecular-2 (ICAM-2) (CD102), and lack of expression of other beta 2-integrin ligands, ICAM-1 (CD54) and ICAM-3 (CD50), on the surface of resting and stimulated platelets. ICAM-2 isolated from platelets migrates as a band of 59,000 M(r) in reducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Staining of bone marrow aspirates with anti-ICAM-2 mAb demonstrates strong reactivity to megakaryocytes. Using frozen thin sections and immunogold labeling, the antigen was shown to be present on the plasma membrane and surface-connected canalicular system of resting platelets. The average number of ICAM-2 molecules per platelet is 3,000 +/- 230 and does not change after activation. In adhesion assays, resting and stimulated platelets were capable of binding through ICAM-2 to purified leukocyte function-associated antigen-1. Activation of T lymphocytes with PMA stimulated binding to platelets that was Mg2+ dependent and could be specifically inhibited by mAbs to either ICAM-2 or leukocyte function-associated antigen-1. ICAM-2 is the only known beta 2-integrin ligand present on platelets, suggesting that it may play an important role in leukocyte-platelet interactions in inflammation and thrombosis. Images PMID:8083366

  5. Circulating adhesion molecules after short-term exposure to particulate matter among welders

    PubMed Central

    Fang, S C; Eisen, E A; Cavallari, J M; Mittleman, M A; Christiani, D C

    2011-01-01

    Background Studies from several countries indicate that welders experience increased risk of mortality and morbidity from ischaemic heart disease. Although the underlying mechanisms are unclear, vascular responses to particulate matter contained in welding fumes may play a role. To investigate this, we studied the acute effects of welding fume exposure on the endothelial component of vascular function, as measured by circulating adhesion molecules involved in leukocyte adhesion (sICAM-1 and sVCAM-1) and coagulation (vWF). Methods A panel of 26 male welders was studied repeatedly across a 6 h work-shift on a high exposure welding day and/or a low exposure non-welding day. Personal PM2.5 exposure was measured throughout the work-shift. Blood samples were collected in the morning (baseline) prior to the exposure period, immediately after the exposure period, and the following morning. To account for the repeated measurements, we used linear mixed models to evaluate the effects of welding (binary) and PM2.5 (continuous) exposure on each blood marker, adjusting for baseline blood marker concentration, smoking, age and time of day. Results Welding and PM2.5 exposure were significantly associated with a decrease in sVCAM-1 in the afternoon and the following morning and an increase in vWF in the afternoon. Conclusions The data suggest that welding and short-term occupational exposure to PM2.5 may acutely affect the endothelial component of vascular function. PMID:19736177

  6. N-glycosylation controls the function of junctional adhesion molecule-A

    PubMed Central

    Scott, David W.; Tolbert, Caitlin E.; Graham, David M.; Wittchen, Erika; Bear, James E.; Burridge, Keith

    2015-01-01

    Junctional adhesion molecule-A (JAM-A) is an adherens and tight junction protein expressed by endothelial and epithelial cells. JAM-A serves many roles and contributes to barrier function and cell migration and motility, and it also acts as a ligand for the leukocyte receptor LFA-1. JAM-A is reported to contain N-glycans, but the extent of this modification and its contribution to the protein’s functions are unknown. We show that human JAM-A contains a single N-glycan at N185 and that this residue is conserved across multiple mammalian species. A glycomutant lacking all N-glycans, N185Q, is able to reach the cell surface but exhibits decreased protein half-life compared with the wild- type protein. N-glycosylation of JAM-A is required for the protein’s ability to reinforce barrier function and contributes to Rap1 activity. We further show that glycosylation of N185 is required for JAM-A–mediated reduction of cell migration. Finally, we show that N-glycosylation of JAM-A regulates leukocyte adhesion and LFA-1 binding. These findings identify N-glycosylation as critical for JAM-A’s many functions. PMID:26224316

  7. Lymphocyte adhesion molecules in T cell-mediated lysis of human kidney cells.

    PubMed

    Suranyi, M G; Bishop, G A; Clayberger, C; Krensky, A M; Leenaerts, P; Aversa, G; Hall, B M

    1991-02-01

    The complementary adhesion molecules LFA-1 (CD11a, 18)/ICAM-1 (CD54) and LFA-2 (CD2)/LFA-3 (CD58) have been shown to be important in T cell interaction with lymphoid target cells. The role of these ligand pairs in cytotoxicity against somatic cells is less well established. While LFA-3 is expressed by all cells in the kidney, ICAM-1 expression is low in normal kidneys but is increased in allograft rejection. An in vitro cytotoxicity assay was used to examine the relative importance of the two adhesion ligands in immune damage against kidney cells in rejection. HLA-A2 specific cytotoxic T lymphocyte (CTL) recognition of cultured human kidney cells (HKC), of predominantly renal tubular cell origin, was studied. Immunofluorescence studies showed that both induced and uninduced HKC target cells expressed ICAM-1, MHC class I and LFA-3, but only MHC class I and class II antigens and ICAM-1 were significantly upregulated by cytokine induction. Effector cells expressed LFA-1 and LFA-2 but little or no ICAM-1 and LFA-3. Cytokine induction of ICAM-1 expression on HKC target cells increased their susceptibility to lysis. Monoclonal antibody against ICAM-1 or LFA-1 produced the greatest inhibition of HKC lysis, and their effects were not additive. Antibody against LFA-2 (CD2) or LFA-3 also produced significant inhibition, but to a lesser degree, and no additive effect was found.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1706002

  8. Adhesion molecules on the endothelium and mononuclear cells in human atherosclerotic lesions.

    PubMed Central

    van der Wal, A. C.; Das, P. K.; Tigges, A. J.; Becker, A. E.

    1992-01-01

    Atherosclerotic lesions show features of a cell-mediated immune inflammatory process. From this viewpoint, the potential role of arterial endothelium in the recruitment of mononuclear cells (T lymphocytes and macrophages) was studied. The endothelium of diffuse intimal thickening (DIT) and atheromatous plaques (AP) in human coronary arteries and abdominal aortas was characterized for the expression of adhesion molecules ELAM-1, ICAM-1, and the major histocompatibility complex (MHC) class II antigens HLA-DR/DP. A marked increase in expression of ICAM-1 and ELAM-1, and to a lesser extent HLA-DR/DP was observed on endothelial cells that were adjacent to subendothelial infiltrates of T lymphocytes (CD3+, CD11a+, HLA-DR/DP+) and macrophages (CD14+, CD11a+, CD11c+, HLA-DR/DP+). This contrasted with a lower or absent expression of these activation markers at sites without prominent inflammatory cell infiltrates. These findings could be demonstrated in DIT as well as in AP. The observations suggest that cytokines produced by the subintimal infiltrates may activate the endothelium in a similar way as is observed in the microvasculature at sites of immune inflammation. The expression of these activation markers in the microvasculature is associated with enhanced leukocyte adhesion, permeability for macromolecules, and procoagulant activity, features known to occur also in early experimental atherosclerosis. The findings therefore support the concept that arterial endothelium plays an active role in the recruitment of mononuclear cells in atherosclerotic lesions. Images Figure 1 PMID:1281621

  9. Intracellular transport and cell surface delivery of the neural cell adhesion molecule (NCAM).

    PubMed

    Leshchyns'ka, Iryna; Sytnyk, Vladimir

    2015-01-01

    The neural cell adhesion molecule (NCAM) regulates differentiation and functioning of neurons by accumulating at the cell surface where it mediates the interactions of neurons with the extracellular environment. NCAM also induces a number of intracellular signaling cascades, which coordinate interactions at the cell surface with intracellular processes including changes in gene expression, transport and cytoskeleton remodeling. Since NCAM functions at the cell surface, its transport and delivery to the cell surface play a critical role. Here, we review recent advances in our understanding of the molecular mechanisms of the intracellular transport and cell surface delivery of NCAM. We also discuss the data suggesting a possibility of cross talk between activation of NCAM at the cell surface and the intracellular transport and cell surface delivery of NCAM.

  10. The leucine-rich repeat superfamily of synaptic adhesion molecules: LRRTMs and Slitrks.

    PubMed

    Ko, Jaewon

    2012-10-01

    Synapses are asymmetric intercellular junctions connected by multiple synaptic cell adhesion molecules (CAMs). Synaptic CAMs function in various stages of synaptogenesis - the process of synapse creation - encompassing synapse formation, maturation, refinement, plasticity, and elimination. The list of synaptic CAMs has rapidly grown, although their precise functions of most CAMs at synapses remain incomplete. Members of an emerging class of transmembrane proteins containing leucine-rich repeat (LRR) domains have received considerable recent research attention. In this minireview, I discuss recent findings on LRR-containing synaptic CAMs that impact synapse development and circuit formation, focusing on two families of LRR synaptic CAMs: leucine-rich transmembrane proteins (LRRTMs) and Slit and Trk-like family (Slitrks). Their basic biochemical properties, proposed functions at synapses, physiological significances, and open questions are summarized.

  11. The L1 family of cell adhesion molecules: a sickening number of mutations and protein functions.

    PubMed

    Hortsch, Michael; Nagaraj, Kakanahalli; Mualla, Rula

    2014-01-01

    L1-type proteins are transmembrane cell adhesion molecules with an evolutionary well-conserved protein domain structure of usually six immunoglobulin and five fibronectin type III domains. By engaging in many different protein-protein interactions they are involved in a multitude of molecular functions and are important players during the formation and maintenance of metazoan nervous systems. As a result, mutations in L1-type genes cause a great variety of phenotypes, most of which are neurological in nature. In humans, mutations in the L1CAM gene are responsible for L1 syndrome and other L1-type genes have been implicated in conditions as varied as mental retardation, autism, schizophrenia, multiple sclerosis, and other disorders. Equally, the overexpression of L1-type proteins appears to have deleterious effects in various types of human tumor cells, where they generally contribute to an increase in cell mobility and metastatic potential. PMID:25300138

  12. Identification of DNA Aptamers toward Epithelial Cell Adhesion Molecule via Cell-SELEX

    PubMed Central

    Kim, Ji Won; Kim, Eun Young; Kim, Sun Young; Byun, Sang Kyung; Lee, Dasom; Oh, Kyoung-Jin; Kim, Won Kon; Han, Baek Soo; Chi, Seung-Wook; Lee, Sang Chul; Bae, Kwang-Hee

    2014-01-01

    The epithelial cell adhesion molecule (EpCAM, also known as CD326) is a transmembrane glycoprotein that is specifically detected in most adenocarcinomas and cancer stem cells. In this study, we performed a Cell systematic evolution of ligands by exponential enrichment (SELEX) experiment to isolate the aptamers against EpCAM. After seven round of Cell SELEX, we identified several aptamer candidates. Among the selected aptamers, EP166 specifically binds to cells expressing EpCAM with an equilibrium dissociation constant (Kd) in a micromolar range. On the other hand, it did not bind to negative control cells. Moreover, EP166 binds to J1ES cells, a mouse embryonic stem cell line. Therefore, the isolated aptamers against EpCAM could be used as a stem cell marker or in other applications in both stem cell and cancer studies. PMID:25266702

  13. 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

  14. Neutrophil and monocyte adhesion molecules in bronchopulmonary dysplasia, and effects of corticosteroids

    PubMed Central

    Ballabh, P; Simm, M; Kumari, J; Krauss, A; Jain, A; Califano, C; Lesser, M; Cunningham-Rundle..., S

    2004-01-01

    Aims: To study a longitudinal change in the expression of adhesion molecules CD11b, CD18, and CD62L on neutrophils and monocytes in very low birth weight babies who develop respiratory distress syndrome, to compare these levels between bronchopulmonary dysplasia (BPD) and non-BPD infants, and to assess the effect of corticosteroid treatment on these adhesion molecules. Methods: Of 40 eligible neonates, 11 neonates were oxygen dependent at 36 weeks (BPD 36 weeks), 16 infants were oxygen dependent at 28 days, but not at 36 weeks (BPD d28), and 13 infants did not develop BPD. Seventeen neonates received a six day course of steroid treatment. Expression of CD11b, CD18, and CD62L was measured on neutrophils and monocytes in arterial blood on days 1, 3, 7, 14, 21, and 28, and before and 2–3 days after initiation of dexamethasone treatment by flow cytometry. Results: CD18 expression on neutrophils and monocytes and CD62L on neutrophils, measured as mean fluorescent intensity, was significantly decreased in BPD neonates compared to non-BPD neonates on days 1–28. Dexamethasone treatment significantly decreased CD11b, CD18, and CD62L expression on neutrophils, and CD11b and CD18L expression on monocytes. Conclusions: Decreased CD18 expression on neutrophils and monocytes, and decreased CD62L expression on neutrophils, measured as mean fluorescent intensity during the first four weeks of life in micropremies may be risk factors and early predictors of BPD. Dexamethasone use was associated with decreased expression of CD11b, CD18, and CD62L. PMID:14711863

  15. Soluble Adhesion Molecules in Patients Coinfected with HIV and HCV: A Predictor of Outcome

    PubMed Central

    Aldámiz-Echevarría, Teresa; Berenguer, Juan; Miralles, Pilar; Jiménez-Sousa, María A.; Carrero, Ana; Pineda-Tenor, Daniel; Díez, Cristina; Tejerina, Francisco; Pérez-Latorre, Leire; Bellón, José M.; Resino, Salvador

    2016-01-01

    Background Higher serum levels of adhesion molecules (sICAM-1 and sVCAM-1) are associated with advanced liver fibrosis in patients coinfected with human immunodeficiency virus and hepatitis C virus. We assessed the relationship between serum levels of adhesion molecules and liver-related events (LRE) or death, in coinfected patients. Methods We studied clinical characteristics and outcomes of 182 coinfected patients with a baseline liver biopsy (58 with advanced fibrosis) and simultaneous plasma samples who were followed for median of 9 years. We used receiver-operating characteristic (ROC) curves to calculate optimized cutoff values (OCV) of sICAM-1 and sVCAM-1, defined as the values with the highest combination of sensitivity and specificity for LRE. We used multivariate regression analysis to test the association between OCVs of sICAM-1 and sVCAM-1 and outcomes. The variables for adjustment were age, HIV transmission category, liver fibrosis, baseline CD4+ T-cell counts, antiretroviral therapy, and sustained virologic response (SVR). Results During the study period 51 patients had SVR, 19 had LRE, and 16 died. The OCVs for LRE were 5.68 Log pg/mL for sICAM-1 and 6.25 Log pg/mL for sVCAM-1, respectively. The adjusted subhazard ratio (aSHR) (95% confidence interval [CI]) of death or LRE, whichever occurred first, for sICAM-1 and sVCAM-1 > OCV were 3.98 ([1.14; 13.89], P = 0.030) and 2.81 ([1.10; 7.19], respectively (P = 0.030). Conclusions Serum levels of sICAM-1 and sVCAM-1 can serve as markers of outcome in HIV/HCV-coinfected patients. Therapies targeting necroinflammatory damage and fibrogenesis may have a role in the management chronic hepatitis C. PMID:26849641

  16. Characterization of hepatocellular carcinoma cell lines based on cell adhesion molecules.

    PubMed

    Jung, Cheol Woong; Song, Tae-Jin; Lee, Kun-Ok; Choi, Sae Byeol; Kim, Wan Bae; Suh, Sung Ock; Kim, Young Chul; Choi, Sang Yong

    2012-06-01

    Many studies which focus on the molecules and mechanisms related to the characteristics of the cancer have been performed. In particular, cell adhesion molecules (CAMs) are known to play a central role in the adhesion of cancer cells to vascular endothelial cells. In this study, the expression of CAMs in hepatocellular carcinoma (HCC) cell lines was analyzed and correlated with the characteristics of various HCC cell lines. Eight human HCC cell lines were used in this study. We analyzed the expression of ICAM-1, E-selectin and the integrin subunits of HCC cell lines by western blot analysis and ELISA kit. We estimated the expression of integrin-α5 using western blot analysis and RT-PCR to compare the expression at the gene level with the protein level. In addition, we determined the expression of TGF-β1, as one of the markers for the cellular activity compared to the levels of expression with the expression of integrin-α3 and -α5. ICAM-1 was highly expressed in all of the cell lines except SNU398 and Hep3B, which exhibit a more aggressive nature among the studied HCC cell lines. E-selectin and integrin subunits varied in all HCC cell lines. In particular, integrin-β2 was highly expressed on all HCC cell lines. In conclusion, the levels of expression of the CAMs may not affect cellular activity, morphology or tumorigenicity. However, most HCC cell lines show various expressions of CAMs, suggesting that HCC cell lines expressing the major CAMs remain candidates for molecular targeted therapy, which may need to be patient-tailored for therapy according to the molecular profile.

  17. Evaluation of soluble adhesion molecules in the diagnosis of amoebiasis, giardiasis and toxoplasmosis.

    PubMed

    el-Shazly, A M; Soliman, M; el-Kalla, M R; Rezk, H; el-Nemr, H; Handoussa, A E; el-Aaty, H E; Morsy, T A

    2001-12-01

    A total of 47 patients with toxoplasmosis (21 cases) with amoebic liver abscess (14 cases) and with giardiasis (12 cases) as well as 14 healthy control were subjected to thorough history taking, clinical examination, stool & urine analysis, complete blood picture, ESR, C-reactive protein, ASO, widal test, blood cultures, liver function tests, serum creatinine, hepatitis viral markers, rheumatoid factor, auto-antibodies, stool culture, rectal snip, chest X-ray, abdominal sonar, level of serum adhesion molecules (sICAM-1, sELAM-1), ELISA detection of Toxoplasma antibodies in serum, liver biopsy, detection and counting of Giardia cysts. In toxoplasmosis group, highly significant increase in serum levels of sICAM-1 (P<0.01) and significant increase in serum levels of sELAM-1 (P<0.05) in comparison to control. However, only sICAM-1 levels were significantly increased in IgM cases more than in IgG cases. In amoebic liver abscess group, both sICAM-1 and sELAM-1 significantly increased when compared with control. In giardiasis group, highly significant increase of serum levels of sELAM-1 was noticed than in control group (P<0.01), while sICAM-1 showed no significant difference (P>0.05). There was no correlation between sELAM-1 and number of cysts in the stool (intensity of infection). Soluble forms of adhesion molecules especially sICAM-1 have the potentiality as good markers of endothelial damage, severity of disease and to less extend load of infection.

  18. Intercellular Adhesion Molecule 1 and Progression of Percent Emphysema: The MESA Lung Study

    PubMed Central

    Aaron, Carrie P.; Schwartz, Joseph E.; Bielinski, Suzette J.; Hoffman, Eric A.; Austin, John H. M.; Oelsner, Elizabeth C.; Donohue, Kathleen M.; Kalhan, Ravi; Berardi, Cecilia; Kaufman, Joel D.; Jacobs, David R.; Tracy, Russell P.; Barr, R.Graham

    2014-01-01

    Endothelial intercellular adhesion molecule (ICAM) 1 binds neutrophils and facilitates their transmigration into the lung; E-selectin facilitates leukocyte rolling. As neutrophils contribute to tissue destruction in emphysema and chronic obstructive pulmonary disease, we hypothesized that soluble ICAM-1 (sICAM-1) and E-selectin (sE-selectin) would be associated with longitudinal progression of emphysema and lung function decline. The Multi-Ethnic Study of Atherosclerosis (MESA) enrolled participants 45-84 years old without clinical cardiovascular disease in 2000-02. The MESA Lung Study assessed percent emphysema (<-950 Hounsfield units) on cardiac (2000-07) and full-lung CT scans (2010-12), and spirometry was assessed twice over five years. sICAM-1 and sE-selectin were measured at baseline. Mixed-effect models adjusted for demographics, anthropometry, smoking, C-reactive protein, sphingomyelin and scanner factors. Among 1,865 MESA Lung participants with measurement of sICAM-1 and percent emphysema the mean log-sICAM-1 was 5.5±0.3 ng/mL and percent emphysema increased 0.73 percentage points (95% CI: 0.34, 1.12; P<0.001) over ten years. A one SD increase in sICAM-1 was associated with an accelerated increase in percent emphysema of 0.23 percentage points over ten years (95% CI: 0.06, 0.39; P=0.007). No significant association was found for sE-selectin, or between any adhesion molecule and lung function. Higher levels of sICAM-1 were independently associated with progression of percent emphysema in a general population sample. PMID:25457724

  19. Identification of Small-Molecule Scaffolds for P450 Inhibitors

    PubMed Central

    von Kries, Jens P.; Warrier, Thulasi; Podust, Larissa M.

    2015-01-01

    Mycobacterium tuberculosis cytochrome P450 enzymes (P450, CYP) attract ongoing interest for their pharmacological development potential, as evidenced by the activity of antifungal azole drugs that inhibit sterol 14α-demethylase CYP51 in fungi, tightly bind M. tuberculosis CYP enzymes, and display inhibitory potential against latent and multi drug resistant forms of tuberculosis both in vitro and in tuberculosis-infected mice. Although “piggy-backing” onto existing antifungal drug development programs would have obvious practical and economic benefits, the substantial differences between fungal CYP51 and potential CYP targets in M. tuberculosis are driving direct screening efforts against CYP enzymes with the ultimate goal of developing potent CYP-specific inhibitors and/or molecular probes to address M. tuberculosis biology. The property of CYP enzymes to shift the ferric heme Fe Soret band in response to ligand binding provides the basis for an experimental platform for high throughput screening (HTS) of compound libraries to select chemotypes with high binding affinities to the target. Newly discovered compounds can be evaluated in in vitro assays or in vivo disease models for inhibitory/therapeutic effects. The best inhibitors in complex with the target protein can be further characterized by x-ray crystallography. In conjunction with knowledge about compound inhibition potential, detailed structural characterization of the protein-inhibitor binding mode can guide lead optimization strategies to assist drug design. This unit includes protocols for compound library screening, analysis of inhibitory potential of the screen hits, and co-crystallization of top hits with the target CYP. Support protocols are provided for expression and purification of soluble CYP enzymes. PMID:20131225

  20. Targeting Staphylococcus aureus Quorum Sensing with Nonpeptidic Small Molecule Inhibitors

    PubMed Central

    2014-01-01

    A series of 3-oxo-C12-HSL, tetramic acid, and tetronic acid analogues were synthesized to gain insights into the structural requirements for quorum sensing inhibition in Staphylococcus aureus. Compounds active against agr were noncompetitive inhibitors of the autoinducing peptide (AIP) activated AgrC receptor, by altering the activation efficacy of the cognate AIP-1. They appeared to act as negative allosteric modulators and are exemplified by 3-tetradecanoyltetronic acid 17, which reduced nasal cell colonization and arthritis in a murine infection model. PMID:24592914

  1. Targeting PTPs with small molecule inhibitors in cancer treatment

    PubMed Central

    Jiang, Zhong-Xing; Zhang, Zhong-Yin

    2009-01-01

    Protein tyrosine phosphorylation plays a major role in cellular signaling. The level of tyrosine phosphorylation is controlled by protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs). Disturbance of the normal balance between PTK and PTP activity results in aberrant tyrosine phosphorylation, which has been linked to the etiology of several human diseases, including cancer. A number of PTPs have been implicated in oncogenesis and tumor progression and therefore are potential drug targets for cancer chemotherapy. These include PTP1B, which may augment signaling downstream of HER2/Neu; SHP2, which is the first oncogene in the PTP superfamily and is essential for growth factor-mediated signaling; the Cdc25 phosphatases, which are positive regulators of cell cycle progression; and the PRL phosphatases, which promote tumor metastases. As PTPs have emerged as drug targets for cancer, a number of strategies are currently been explored for the identification of various classes of PTP inhibitors. These efforts have resulted many potent, and in some cases selective, inhibitors for PTP1B, SHP2, Cdc25 and PRL phosphatases. Structural information derived from these compounds serves as a solid foundation upon which novel anti-cancer agents targeted to these PTPs can be developed. PMID:18259840

  2. Osteoblast adhesion to orthopaedic implant alloys: Effects of cell adhesion molecules and diamond-like carbon coating

    SciTech Connect

    Kornu, R.; Kelly, M.A.; Smith, R.L.; Maloney, W.J.

    1996-11-01

    In total joint arthroplasty, long-term outcomes depend in part on the biocompatibility of implant alloys. This study analyzed effects of surface finish and diamond-like carbon coating on osteoblast cell adhesion to polished titanium-aluminum-vanadium and polished or grit-blasted cobalt-chromium-molybdenum alloys. Osteoblast binding was tested in the presence and absence of the cell adhesion proteins fibronectin, laminin, fibrinogen, and vitronectin and was quantified by measurement of DNA content. Although adherence occurred in serum-free medium, maximal osteoblast binding required serum and was similar for titanium and cobalt alloys at 2 and 12 hours. With the grit-blasted cobalt alloy, cell binding was reduced 48% (p < 0.05) by 24 hours. Coating the alloys with diamond-like carbon did not alter osteoblast adhesion, whereas fibronectin pretreatment increased cell binding 2.6-fold (p < 0.05). In contrast, fibrinogen, vitronectin, and laminin did not enhance cell adhesion. These results support the hypothesis that cell adhesion proteins can modify cell binding to orthopaedic alloys. Although osteoblast binding was not affected by the presence of diamond-like carbon, this coating substance may influence other longer term processes, such as bone formation, and deserves further study. 40 refs., 4 figs.

  3. Adhesions

    MedlinePlus

    ... surfaces so they can shift easily as the body moves. Adhesions cause tissues and organs to stick together. They might connect the loops of the intestines to each other, to nearby ... can occur anywhere in the body. But they often form after surgery on the ...

  4. Surface morphology of platelet adhesion influenced by activators, inhibitors and shear stress

    NASA Astrophysics Data System (ADS)

    Watson, Melanie Groan

    Platelet activation involves multiple events, one of which is the generation and release of nitric oxide (NO), a platelet aggregation inhibitor. Platelets simultaneously send and receive various agents that promote a positive and negative feedback control system during hemostasis. Although the purpose of platelet-derived NO is not fully understood, NO is known to inhibit platelet recruitment. NO's relatively large diffusion coefficient allows it to diffuse more rapidly than platelet agonists. It may thus be able to inhibit recruitment of platelets near the periphery of a growing thrombus before agonists have substantially accumulated in those regions. Results from two studies in our laboratory differed in the extent to which platelet-derived NO decreased platelet adhesion. Frilot studied the effect of L-arginine (L-A) and NG-Methyl-L-arginine acetate salt (L-NMMA) on platelet adhesion to collagen under static conditions in a Petri dish. Eshaq examined the percent coverage on collagen-coated and fibrinogen-coated microchannels under shear conditions with different levels of L-A and Adenosine Diphosphate (ADP). Frilot's results showed no effect of either L-A or L-NMMA on surface coverage, thrombus size or serotonin release, while Eshaq's results showed a decrease in surface coverage with increased levels of L-A. A possible explanation for these contrasting results is that platelet-derived NO may be more important under flow conditions than under static conditions. For this project, the effects of L-A. ADP and L-NMMA on platelet adhesion were studied at varying shear stresses on protein-coated glass slides. The surface exposed to platelet-rich-plasma in combination with each chemical solution was observed under AFM, FE-SEM and fluorescence microscopy. Quantitative and qualitative comparisons of images obtained with these techniques confirmed the presence of platelets on the protein coatings. AFM images of fibrinogen and collagen-coated slides presented characteristic

  5. The role of cellular adhesion molecules in virus attachment and entry

    PubMed Central

    Bhella, David

    2015-01-01

    As obligate intracellular parasites, viruses must traverse the host-cell plasma membrane to initiate infection. This presents a formidable barrier, which they have evolved diverse strategies to overcome. Common to all entry pathways, however, is a mechanism of specific attachment to cell-surface macromolecules or ‘receptors’. Receptor usage frequently defines viral tropism, and consequently, the evolutionary changes in receptor specificity can lead to emergence of new strains exhibiting altered pathogenicity or host range. Several classes of molecules are exploited as receptors by diverse groups of viruses, including, for example, sialic acid moieties and integrins. In particular, many cell-adhesion molecules that belong to the immunoglobulin-like superfamily of proteins (IgSF CAMs) have been identified as viral receptors. Structural analysis of the interactions between viruses and IgSF CAM receptors has not shown binding to specific features, implying that the Ig-like fold may not be key. Both proteinaceous and enveloped viruses exploit these proteins, however, suggesting convergent evolution of this trait. Their use is surprising given the usually occluded position of CAMs on the cell surface, such as at tight junctions. Nonetheless, the reason for their widespread involvement in virus entry most probably originates in their functional rather than structural characteristics. PMID:25533093

  6. Azastilbene Analogs as Tyrosinase Inhibitors: New Molecules with Depigmenting Potential

    PubMed Central

    Lima, Larissa Lavorato; Lima, Rebeca Mól; da Silva, Annelisa Farah; do Carmo, Antônio Márcio Resende; da Silva, Adilson David; Raposo, Nádia Rezende Barbosa

    2013-01-01

    This research has been an effort to develop synthetic resveratrol analogs in order to improve the depigmenting potential of natural resveratrol. Six resveratrol analogs were synthesized and tested for tyrosinase inhibitory activity in vitro, by qualitative and quantitative steps. The results showed the analog C as being the most powerful tyrosinase inhibitor (IA50 = 65.67 ± 0.60 μg/mL), followed by the analogs B, E, F, A, and D, respectively. The analog C presented a tyrosinase inhibition potential better than natural resveratrol (P < 0.001). The best depigmenting activity was provided by the presence of hydroxyl in the orthoposition on the second phenolic ring. PMID:23476126

  7. Identification of Novel Small Molecule Inhibitors of Oncogenic RET Kinase.

    PubMed

    Moccia, Marialuisa; Liu, Qingsong; Guida, Teresa; Federico, Giorgia; Brescia, Annalisa; Zhao, Zheng; Choi, Hwan Geun; Deng, Xianming; Tan, Li; Wang, Jinhua; Billaud, Marc; Gray, Nathanael S; Carlomagno, Francesca; Santoro, Massimo

    2015-01-01

    Oncogenic mutation of the RET receptor tyrosine kinase is observed in several human malignancies. Here, we describe three novel type II RET tyrosine kinase inhibitors (TKI), ALW-II-41-27, XMD15-44 and HG-6-63-01, that inhibit the cellular activity of oncogenic RET mutants at two digit nanomolar concentration. These three compounds shared a 3-trifluoromethyl-4-methylpiperazinephenyl pharmacophore that stabilizes the 'DFG-out' inactive conformation of RET activation loop. They blocked RET-mediated signaling and proliferation with an IC50 in the nM range in fibroblasts transformed by the RET/C634R and RET/M918T oncogenes. They also inhibited autophosphorylation of several additional oncogenic RET-derived point mutants and chimeric oncogenes. At a concentration of 10 nM, ALW-II-41-27, XMD15-44 and HG-6-63-01 inhibited RET kinase and signaling in human thyroid cancer cell lines carrying oncogenic RET alleles; they also inhibited proliferation of cancer, but not non-tumoral Nthy-ori-3-1, thyroid cells, with an IC50 in the nM range. The three compounds were capable of inhibiting the 'gatekeeper' V804M mutant which confers substantial resistance to established RET inhibitors. In conclusion, we have identified a type II TKI scaffold, shared by ALW-II-41-27, XMD15-44 and HG-6-63-01, that may be used as novel lead for the development of novel agents for the treatment of cancers harboring oncogenic activation of RET.

  8. The role of novel and known extracellular matrix and adhesion molecules in the homeostatic and regenerative bone marrow microenvironment

    PubMed Central

    Klamer, Sofieke; Voermans, Carlijn

    2014-01-01

    Maintenance of haematopoietic stem cells and differentiation of committed progenitors occurs in highly specialized niches. The interactions of haematopoietic stem and progenitor cells (HSPCs) with cells, growth factors and extracellular matrix (ECM) components of the bone marrow (BM) microenvironment control homeostasis of HSPCs. We only start to understand the complexity of the haematopoietic niche(s) that comprises endosteal, arterial, sinusoidal, mesenchymal and neuronal components. These distinct niches produce a broad range of soluble factors and adhesion molecules that modulate HSPC fate during normal hematopoiesis and BM regeneration. Adhesive interactions between HSPCs and the microenvironment will influence their localization and differentiation potential. In this review we highlight the current understanding of the functional role of ECM- and adhesion (regulating) molecules in the haematopoietic niche during homeostatic and regenerative hematopoiesis. This knowledge may lead to the improvement of current cellular therapies and more efficient development of future cellular products. PMID:25482635

  9. Self-assembled monolayer of designed and synthesized triazinedithiolsilane molecule as interfacial adhesion enhancer for integrated circuit.

    PubMed

    Wang, Fang; Li, Yanni; Wang, Yabin; Cao, Zhuo

    2011-08-03

    Self-assembled monolayer (SAM) with tunable surface chemistry and smooth surface provides an approach to adhesion improvement and suppressing deleterious chemical interactions. Here, we demonstrate the SAM comprising of designed and synthesized 6-(3-triethoxysilylpropyl)amino-1,3,5-triazine-2,4-dithiol molecule, which can enhance interfacial adhesion to inhibit copper diffusion used in device metallization. The formation of the triazinedithiolsilane SAM is confirmed by X-ray photoelectron spectroscopy. The adhesion strength between SAM-coated substrate and electroless deposition copper film was up to 13.8 MPa. The design strategy of triazinedithiolsilane molecule is expected to open up the possibilities for replacing traditional organosilane to be applied in microelectronic industry.

  10. Self-assembled monolayer of designed and synthesized triazinedithiolsilane molecule as interfacial adhesion enhancer for integrated circuit

    PubMed Central

    2011-01-01

    Self-assembled monolayer (SAM) with tunable surface chemistry and smooth surface provides an approach to adhesion improvement and suppressing deleterious chemical interactions. Here, we demonstrate the SAM comprising of designed and synthesized 6-(3-triethoxysilylpropyl)amino-1,3,5-triazine-2,4-dithiol molecule, which can enhance interfacial adhesion to inhibit copper diffusion used in device metallization. The formation of the triazinedithiolsilane SAM is confirmed by X-ray photoelectron spectroscopy. The adhesion strength between SAM-coated substrate and electroless deposition copper film was up to 13.8 MPa. The design strategy of triazinedithiolsilane molecule is expected to open up the possibilities for replacing traditional organosilane to be applied in microelectronic industry. PMID:21812994

  11. Cell adhesion molecules in the pathogenesis of and host defence against microbial infection.

    PubMed Central

    Kerr, J R

    1999-01-01

    Eukaryotic cell adhesion molecules (CAMs) are used by various cells and extracellular molecules in host defence against infection. They are involved in many processes including recognition by circulating phagocytes of a site of inflammation, transmigration through the endothelial barrier, diapedesis through basement membrane and extracellular matrix, and release of effector mechanisms at the infected site. CAMs involved in leucocyte-endothelial cell interaction include the selectins, integrins, and members of the immunoglobulin superfamily. However, CAMs are also used by various microorganisms (protozoa, fungi, bacteria, and viruses) during their pathogenesis. For example, bacteria that utilise CAMs include Mycobacterium tuberculosis, Listeria monocytogenes, Yersinia spp, enteropathogenic Escherichia coli, Shigella spp, Neisseria spp, Bordetella spp, and Borrelia burgdorferi. In addition, CAMs are involved in the pathogenetic effects of the RTX toxins of Pasteurella haemolytica, Actinobacillus actinomycetemcomitans, and the superantigen exotoxins of Staphylococcus aureus and Streptococcus pyogenes. A recurrent and topical theme of potential importance within the bacterial group is the intimate relation between CAMs, bacterial protein receptors, and type III secretion systems. For example, the IpaBCD protein complex is secreted by the type III system of Shigella flexneri and interacts with alpha 5 beta 1 integrin on the eukaryotic cell surface, followed by Rho mediated internalisation; this illustrates the relevance of cellular microbiology. CAMs might prove to be novel therapeutic targets. Comparative genomics has provided the knowledge of shared virulence determinants among diverse bacterial genera, and will continue to deepen our understanding of microbial pathogenesis, particularly in the context of the interaction of prokaryotic and eukaryotic molecules. PMID:10694943

  12. Age-Related Cognitive Impairments in Mice with a Conditional Ablation of the Neural Cell Adhesion Molecule

    ERIC Educational Resources Information Center

    Bisaz, Reto; Boadas-Vaello, Pere; Genoux, David; Sandi, Carmen

    2013-01-01

    Most of the mechanisms involved in neural plasticity support cognition, and aging has a considerable effect on some of these processes. The neural cell adhesion molecule (NCAM) of the immunoglobulin superfamily plays a pivotal role in structural and functional plasticity and is required to modulate cognitive and emotional behaviors. However,…

  13. A Chinese Herbal Preparation Containing Radix Salviae Miltiorrhizae, Radix Notoginseng and Borneolum Syntheticum Reduces Circulating Adhesion Molecules

    PubMed Central

    O'Brien, Kylie A.; Ling, Shanhong; Abbas, Estelle; Dai, Aozhi; Zhang, Jiansheng; Wang, Wen Cheng; Bensoussan, Alan; Luo, Ruizhi; Guo, Zhi-Xin; Komesaroff, Paul A.

    2011-01-01

    Circulating adhesion molecules (CAMs), surface proteins expressed in the vascular endothelium, have emerged as risk factors for cardiovascular disease (CVD). CAMs are involved in intercellular communication that are believed to play a role in atherosclerosis. A Chinese medicine, the “Dantonic Pill” (DP) (also known as the “Cardiotonic Pill”), containing three Chinese herbal material medica, Radix Salviae Miltiorrhizae, Radix Notoginseng and Borneolum Syntheticum, has been used in China for the prevention and management of CVD. Previous laboratory and animal studies have suggested that this preparation reduces both atherogenesis and adhesion molecule expression. A parallel double blind randomized placebo-controlled study was conducted to assess the effects of the DP on three species of CAM (intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 and endothelial cell selectin (E-selectin)) in participants with mild-moderate hypercholesterolemia. Secondary endpoints included biochemical and hematological variables and clinical effects. Forty participants were randomized to either treatment or control for 12 weeks. Treatment with DP was associated with a statistically significant decrease in ICAM-1 (9% decrease, P = .03) and E-Selectin (15% decrease, P = .004). There was no significant change in renal function tests, liver function tests, glucose, lipids or C-reactive protein levels and clinical adverse effects did not differ between the active and the control groups. There were no relevant changes in participants receiving placebo. These results suggest that this herbal medicine may contribute to the development of a novel approach to cardiovascular risk reduction. PMID:18955365

  14. Medullary carcinoma is associated with expression of intercellular adhesion molecule-1. Implication to its morphology and its clinical behavior.

    PubMed Central

    Bacus, S. S.; Zelnick, C. R.; Chin, D. M.; Yarden, Y.; Kaminsky, D. B.; Bennington, J.; Wen, D.; Marcus, J. N.; Page, D. L.

    1994-01-01

    The histological hallmarks for the diagnosis of medullary breast cancer are circumscription, syncytial architecture, diffuse inflammatory infiltrate, and highly atypical nuclei. The biological and prognostic implication is a lower propensity to metastasize. We studied 19 medullary carcinomas for expression of the intercellular adhesion molecule-1 and lymphocyte-function-associated antigen-1, Neu differentiation factor, tumor necrosis factor-alpha, and the expression of HER-2/neu, HER-4, and HER-3 receptors. Our study revealed that all of the 19 medullary carcinomas expressed the intercellular adhesion molecule-1 and lymphocyte function associated antigen. Eighteen of 19 cancers expressed Neu differentiation factor and tumor necrosis factor-alpha. All medullary cancers expressed the HER-2/neu receptor, however, in the majority of the cases, the staining was confined to the cytoplasm. Only 4 of 12 cancers expressed HER-4 and none of the eight medullary cancers tested expressed HER-3. By comparison, in a control group of infiltrating ductal carcinomas, expression of intercellular adhesion molecule-1, lymphocyte function associated antigen-1, and Neu differentiation factor was positive in about 25 to 30% of the cases, HER-4 was expressed in 75% and HER-3 in 95% of the cases. Taken together, our observations suggest that the expression of intercellular adhesion molecule-1, lymphocyte function associated antigen, Neu differentiation factor, and tumor necrosis factor-alpha as factors that may affect the special morphology and the biological behavior that characterizes medullary carcinomas. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:7992839

  15. The Neural Cell Adhesion Molecule-Derived Peptide FGL Facilitates Long-Term Plasticity in the Dentate Gyrus in Vivo

    ERIC Educational Resources Information Center

    Dallerac, Glenn; Zerwas, Meike; Novikova, Tatiana; Callu, Delphine; Leblanc-Veyrac, Pascale; Bock, Elisabeth; Berezin, Vladimir; Rampon, Claire; Doyere, Valerie

    2011-01-01

    The neural cell adhesion molecule (NCAM) is known to play a role in developmental and structural processes but also in synaptic plasticity and memory of the adult animal. Recently, FGL, a NCAM mimetic peptide that binds to the Fibroblast Growth Factor Receptor 1 (FGFR-1), has been shown to have a beneficial impact on normal memory functioning, as…

  16. Broad spectrum pro-quorum-sensing molecules as inhibitors of virulence in vibrios.

    PubMed

    Ng, Wai-Leung; Perez, Lark; Cong, Jianping; Semmelhack, Martin F; Bassler, Bonnie L

    2012-01-01

    Quorum sensing (QS) is a bacterial cell-cell communication process that relies on the production and detection of extracellular signal molecules called autoinducers. QS allows bacteria to perform collective activities. Vibrio cholerae, a pathogen that causes an acute disease, uses QS to repress virulence factor production and biofilm formation. Thus, molecules that activate QS in V. cholerae have the potential to control pathogenicity in this globally important bacterium. Using a whole-cell high-throughput screen, we identified eleven molecules that activate V. cholerae QS: eight molecules are receptor agonists and three molecules are antagonists of LuxO, the central NtrC-type response regulator that controls the global V. cholerae QS cascade. The LuxO inhibitors act by an uncompetitive mechanism by binding to the pre-formed LuxO-ATP complex to inhibit ATP hydrolysis. Genetic analyses suggest that the inhibitors bind in close proximity to the Walker B motif. The inhibitors display broad-spectrum capability in activation of QS in Vibrio species that employ LuxO. To the best of our knowledge, these are the first molecules identified that inhibit the ATPase activity of a NtrC-type response regulator. Our discovery supports the idea that exploiting pro-QS molecules is a promising strategy for the development of novel anti-infectives. PMID:22761573

  17. Small Molecule Inhibitors in Acute Myeloid Leukemia: From the Bench to the Clinic

    PubMed Central

    Al-Hussaini, Muneera; DiPersio, John F.

    2014-01-01

    Many patients with acute myeloid leukemia (AML) will eventually develop refractory or relapsed disease. In the absence of standard therapy for this population, there is currently an urgent unmet need for novel therapeutic agents. Targeted therapy with small molecule inhibitors (SMIs) represents a new therapeutic intervention that has been successful for the treatment of multiple tumors (e.g., gastrointestinal stromal tumors, chronic myelogenous leukemia). Hence, there has been great interest in generating selective small molecule inhibitors targeting critical pathways of proliferation and survival in AML. This review highlights a selective group of intriguing therapeutic agents and their presumed targets in both preclinical models and in early human clinical trials. PMID:25025370

  18. Small molecule inhibitor screen identifies synergistic activity of the bromodomain inhibitor CPI203 and bortezomib in drug resistant myeloma

    PubMed Central

    Siegel, Matthew B.; Liu, Selina Qiuying; Davare, Monika A.; Spurgeon, Stephen E.; Loriaux, Marc M.; Druker, Brian J.

    2015-01-01

    Purpose Despite significant therapeutic progress in multiple myeloma, drug resistance is uniformly inevitable and new treatments are needed. Our aim was to identify novel, efficacious small-molecule combinations for use in drug resistant multiple myeloma. Experimental Design A panel of 116 small molecule inhibitors was used to screen resistant myeloma cell lines for potential therapeutic targets. Agents found to have enhanced activity in the bortezomib or melphalan resistant myeloma cell lines were investigated further in combination. Synergistic combinations of interest were evaluated in primary patient cells. Results The overall single-agent drug sensitivity profiles were dramatically different between melphalan and bortezomib resistant cells, however, the bromodomain inhibitor, CPI203, was observed to have enhanced activity in both the bortezomib and melphalan resistant lines compared to their wild-type counterparts. The combination of bortezomib and CPI203 was found to be synergistic in both the bortezomib and melphalan resistant cell lines as well as in a primary multiple myeloma sample from a patient refractory to recent proteasome inhibitor treatment. The CPI203-bortezomib combination led to enhanced apoptosis and anti-proliferative effects. Finally, in contrast to prior reports of synergy between bortezomib and other epigenetic modifying agents, which implicated MYC downregulation or NOXA induction, our analyses suggest that CPI203-bortezomib synergy is independent of these events. Conclusion Our preclinical data supports a role for the clinical investigation of the bromodomain inhibitor CPI203 combined with bortezomib or alkylating agents in resistant multiple myeloma. PMID:26254279

  19. Immunohistochemistry of adhesion molecules, metalloproteinases and NO-synthases in extravillous trophoblast of tubal pregnancy.

    PubMed

    Dubernard, G; Galtier-Fougairolles, M; Cortez, A; Uzan, S; Challier, J C

    2005-12-12

    Trophoblast invasion in uterine pregnancy is fine-tuned for the remodelling of the uterine wall and its vascularization. Tubal pregnancy, which occurs in a limited number of patients, involves a dramatic trophoblast invasion in a context of a poor decidualization. By studying the histology of the extravillous trophoblast (EVC) in the anchoring villi, the Ki67 labelling, the location of several adhesion markers (cytokeratin-7, alpha1, alpha6, alphaV, beta1, beta4 integrin subunits and E-cadherin, V/E-cadherin), metalloproteinases (MMP-2, 9 and11), NOS2 and 3, we aimed to detect the specificity of tubal compared to intrauterine pregnancies. No difference could be observed between meso or anti-salpingial trophoblast proliferation or invasion using Ki67. Cytokeratin-7 allowed detection of spindle-shape EVCs and we identified some decidualized stromal cells. Integrins alpha1, beta1 and alphaV, and V/E-cadherin were expressed mainly in the distal EVC correspondingly to intrauterine pregnancy, with a poor expression of alpha1. Integrins alpha6 and beta4, E-cadherin were detected in the distal EVC in contrast to uterine pregnancy. MMP-2, 9, 11 were also shown in distal EVC. NOS2 and 3 labelled the perivascular EVC and NOS3 the endothelial cells of the tubal vessels. These changed distributions of adhesion molecules and MMP together with that of the basic and inducible NOS expressions could be related to mechanical effects in superficial implantation or to a failure of decidualization in tubal pregnancies.

  20. Dynamics of unbinding of cell adhesion molecules: Transition from catch to slip bonds

    NASA Astrophysics Data System (ADS)

    Barsegov, V.; Thirumalai, D.

    2005-02-01

    The unbinding dynamics of complexes involving cell-adhesion molecules depends on the specific ligands. Atomic force microscopy measurements have shown that for the specific P-selectin-P-selectin glycoprotein ligand (sPSGL-1) the average bond lifetime t initially increases (catch bonds) at low (10 pN) constant force, f, and decreases when f > 10 pN (slip bonds). In contrast, for the complex with G1 anti-P-selectin monoclonal antibody t monotonically decreases with f. To quantitatively map the energy landscape of such complexes we use a model that considers the possibility of redistribution of population from one force-free state to another force-stabilized bound state. The excellent agreement between theory and experiments allows us to extract energy landscape parameters by fitting the calculated curves to the lifetime measurements for both sPSGL-1 and G1. Surprisingly, the unbinding transition state for P-selectin-G1 complex is close (0.32 nm) to the bound state, implying that the interaction is brittle, i.e., once deformed, the complex fractures. In contrast, the unbinding transition state of the P-selectin-sPSGL-1 complex is far ( 1.5 nm) from the bound state, indicative of a compliant structure. Constant f energy landscape parameters are used to compute the distributions of unbinding times and unbinding forces as a function of the loading rate, rf. For a given rf, unbinding of sPSGL-1 occurs over a broader range of f with the most probable f being an order of magnitude less than for G1. The theory for cell adhesion complexes can be used to predict the outcomes of unbinding of other protein-protein complexes.

  1. Induction of the neural cell adhesion molecule and neuronal aggregation by osteogenic protein 1.

    PubMed Central

    Perides, G; Safran, R M; Rueger, D C; Charness, M E

    1992-01-01

    The neural cell adhesion molecule (N-CAM) plays a fundamental role in nervous system development and regeneration, yet the regulation of the expression of N-CAM in different brain regions has remained poorly understood. Osteogenic protein 1 (OP-1) is a member of the transforming growth factor beta superfamily that is expressed in the nervous system. Treatment of the neuroblastoma-glioma hybrid cell line NG108-15 for 1-4 days with recombinant human OP-1 (hOP-1) induced alterations in cell shape, formation of epithelioid sheets, and aggregation of cells into multilayered clusters. Immunofluorescence studies and Western blots demonstrated a striking differential induction of the three N-CAM isoforms in hOP-1-treated cells. hOP-1 caused a 6-fold up-regulation of the 140-kDa N-CAM, the isoform showing the highest constitutive expression, and a 29-fold up-regulation of the 180-kDa isoform. The 120-kDa isoform was not detected in control NG108-15 cells but was readily identified in hOP-1-treated cells. Incubation of NG108-15 cells with an antisense N-CAM oligonucleotide reduced the induction of N-CAM by hOP-1 and decreased the formation of multilayered cell aggregates. Anti-N-CAM monoclonal antibodies also diminished the formation of multilayered cell aggregates by hOP-1 and decreased cell-cell adhesion when hOP-1-treated NG108-15 cells were dispersed and replated. Thus, hOP-1 produces morphologic changes in NG108-15 cells, at least in part, by inducing N-CAM. These observations suggest that OP-1 or a homologue may participate in the regulation of N-CAM during nervous system development and regeneration. Images PMID:1438217

  2. Increased neutrophil adherence and adhesion molecule mRNA expression in endothelial cells during selenium deficiency.

    PubMed

    Maddox, J F; Aherne, K M; Reddy, C C; Sordillo, L M

    1999-05-01

    Leukocyte aggregation and activation on endothelial cells (EC) are important preliminary events in leukocyte migration into tissue and subsequent inflammation. Thus, an increase in leukocyte adherence has the potential to affect inflammatory disease outcome. Selenium (Se) is an integral part of the antioxidant enzyme glutathione peroxidase (GSH-Px) and plays an important role in the maintenance of the redox state of a cell. Se supplementation in the bovine has been shown to improve the outcome of acute mastitis caused by coliform bacteria, in part by enhancing the speed of neutrophil migration into the affected mammary gland. However, the mechanisms by which Se modulates neutrophil migration have not been elucidated. Therefore, an in vitro model of Se deficiency in primary bovine mammary artery EC was used to examine the impact of Se status on the adhesive properties of EC. The effect of Se on functional activities was examined by measuring neutrophil adherence to Se-deficient and Se-supplemented EC. Se-deficient EC showed significantly enhanced neutrophil adherence when stimulated with tumor necrosis factor alpha (TNF-alpha) for 4 or 24 h, interleukin-1 for 12 h, or H2O2 for 20 min (P < 0.05). To determine the mechanisms underlying these changes in neutrophil adherence, the expression of EC adhesion molecules, ICAM-1, E-selectin, and P-selectin were examined at the molecular level by a competitive reverse transcription-polymerase chain reaction. Results revealed higher mRNA expression for E-selectin and ICAM-1 in Se-deficient EC stimulated with TNF-alpha for 3 and 6 h, and greater expression of P-selectin mRNA in Se-supplemented EC with 3-h TNF-alpha stimulation. These studies provide new information to establish the role of Se nutrition in the initiation of leukocyte adherence to endothelium. PMID:10331495

  3. Identification of small molecule sulfonic acids as ecto-5'-Nucleotidase inhibitors.

    PubMed

    Raza, Rabia; Saeed, Aamer; Lecka, Joanna; Sévigny, Jean; Iqbal, Jamshed

    2012-11-01

    Ecto-5'-Nucleotidase inhibitors have great potential as anti-tumor agents. We have investigated biochemical properties of human and rat ecto-5'-Nucleotidases and characterized 19 small molecule sulfonic acid derivatives as potential inhibitors of ecto-5'-Nucleotidases. We identified 11 potent inhibitors of human and rat ecto-5'-Nucleotidases and checked their selectivity. Compound 10 (Sodium 2,4-dinitrobenzenesulfonate) with K(i) value of 0.66 μM and 19 (N-(4-sulfamoylphenylcarbamothioyl) pivalamide) with K(i) value of 0.78 μM were identified as the most potent inhibitors for human and rat ecto-5'-Nucleotidase, respectively. The present compounds have low molecular weights, water solubility and equal potency as compared to the reported inhibitors.

  4. Development of Small-molecule HIV Entry Inhibitors Specifically Targeting gp120 or gp41

    PubMed Central

    Lu, Lu; Yu, Fei; Cai, Lifeng; Debnath, Asim K.; Jiang, Shibo

    2015-01-01

    Human immunodeficiency virus type 1 (HIV-1) envelope (Env) glycoprotein surface subunit gp120 and transmembrane subunit gp41 play important roles in HIV-1 entry, thus serving as key targets for the development of HIV-1 entry inhibitors. T20 peptide (enfuvirtide) is the first U.S. FDA-approved HIV entry inhibitor; however, its clinical application is limited by the lack of oral availability. Here, we have described the structure and function of the HIV-1 gp120 and gp41 subunits and reviewed advancements in the development of small-molecule HIV entry inhibitors specifically targeting these two Env glycoproteins. We then compared the advantages and disadvantages of different categories of HIV entry inhibitor candidates and further predicted the future trend of HIV entry inhibitor development. PMID:26324044

  5. Endothelial activation by hydrogen peroxide. Selective increases of intercellular adhesion molecule-1 and major histocompatibility complex class I.

    PubMed Central

    Bradley, J. R.; Johnson, D. R.; Pober, J. S.

    1993-01-01

    Products of activated leukocytes may alter vascular endothelial cell (EC) function. For example, ECs respond to leukocyte-derived cytokines, such as tumor necrosis factor (TNF) or interleukin-1, by reversibly altering levels of expression of specific gene products that promote inflammation. In contrast, hydrogen peroxide, a product of TNF-activated neutrophils, can produce irreversible EC injury and death. In this study, we have investigated the effects of subinjurious concentrations of hydrogen peroxide on EC inflammatory functions. Treatment with 50 to 100 mumol/L hydrogen peroxide selectively increases surface expression of intercellular adhesion molecule-1 and major histocompatibility complex class I, but not endothelial leukocyte adhesion molecule-1 (also known as E-selectin), vascular cell adhesion molecule-1, or gp96, a constitutively expressed EC surface protein. Increased major histocompatibility complex class I and intercellular adhesion molecule-1 surface expression is associated with specifically increased messenger RNA levels, suggesting selective endothelial gene activation. Hydrogen peroxide does not activate the transcription factor Nuclear Factor kappa B, an important mediator of TNF-induced gene expression. Co-treatment with hydrogen peroxide inhibits TNF-induced gene expression at 4 hours, an effect which can be attributed to reversible inhibition of TNF binding to EC surface receptors. Hydrogen peroxide also antagonizes the actions of interleukin-1. At 24 hours, TNF and hydrogen peroxide produce, at most, additive increases in intercellular adhesion molecule-1 and major histocompatibility complex class I. These results suggest that subinjurious concentrations of hydrogen peroxide can activate endothelium and that the effects of hydrogen peroxide on ECs differ from those of inflammatory cytokines. Images Figure 3 Figure 4 Figure 5 PMID:8098585

  6. Differential regulation of leukocyte function-associated antigen-1/ intercellular adhesion molecules-1-dependent adhesion and aggregation in HL-60 cells.

    PubMed

    Katagiri, K; Kinashi, T; Irie, S; Katagiri, T

    1996-05-15

    Activation of integrin and organization of cytoskeletal proteins are highly regulated in cell adhesion and aggregation. The interaction of leukocyte function-associated antigen-1 (LFA-1) and intercellular adhesion molecules-1 (ICAM-1) mediates cell adhesion and aggregation, which facilitate leukocyte trafficking to inflamed tissues and augment effector functions. We investigated how LFA-1/ICAM-1-mediated adhesion and aggregation are regulated in HL-60 cells induced to differentiate into neutrophils by retinoic acid (RA). Uninduced HL-60 cells did not bind to ICAM-1 even with stimulation by 12-0-tetradecanoyl phorbol-13-acetate, although they express LFA-1 on the cell surface. When cultured with RA for 24 hours, HL-60 cells were able to adhere to ICAM-1 constitutively. The induction of adhesion did not accompany any change in surface density of LFA-1, indicating that the avidity of LFA-1 was increased. The change in its avidity required de novo synthesis of proteins. Although ICAM-1 was intensely expressed on RA-induced HL-60 cells, these cells did not show any cellular aggregation. The HL-60 cells transfected with the active form of Ras (Val12) exhibited LFA-1/ICAM-1-dependent aggregation by RA stimulation without change in the avidity of LFA-1. In these Ras-transfectants, a cytoskeletal protein, paxillin, was tyrosine-phosphorylated, and the level of F-actin increased. Transforming growth factor (TGF) beta, as well as cytochalasin D, prevented both the tyrosine phosphorylation of paxillin and the aggregation without any effects on the avidity of LFA-1. Thus, an increase in the avidity of LFA-1 was not sufficient for the induction of aggregation, which required activation of Ras and reorganization of cytoskeletal proteins. These results suggest that distinct regulatory mechanisms control LFA-1/ICAM-1-dependent adhesion and aggregation in HL-60 cells differentiating into neutrophils.

  7. Control of density-dependent, cell state-specific signal transduction by the cell adhesion molecule CEACAM1, and its influence on cell cycle regulation

    SciTech Connect

    Scheffrahn, Inka; Singer, Bernhard B.; Sigmundsson, Kristmundur; Lucka, Lothar; Oebrink, Bjoern . E-mail: bjorn.obrink@cmb.ki.se

    2005-07-15

    Growth factor receptors, extracellular matrix receptors, and cell-cell adhesion molecules co-operate in regulating the activities of intracellular signaling pathways. Here, we demonstrate that the cell adhesion molecule CEACAM1 co-regulates growth-factor-induced DNA synthesis in NBT-II epithelial cells in a cell-density-dependent manner. CEACAM1 exerted its effects by regulating the activity of the Erk 1/2 MAP kinase pathway and the expression levels of the cyclin-dependent kinase inhibitor p27{sup Kip1}. Interestingly, both inhibitory and stimulatory effects were observed. Confluent cells continuously exposed to fetal calf serum showed little Erk activity and DNA synthesis compared with sparse cells. Under these conditions, anti-CEACAM1 antibodies strongly stimulated Erk activation, decreased p27 expression, and induced DNA synthesis. In serum-starved confluent cells, re-addition of 10% fetal calf serum activated the Erk pathway, decreased p27 expression, and stimulated DNA synthesis to the same levels as in sparse cells. Under these conditions anti-CEACAM1 antibodies de-activated Erk, restored the level of p27, and inhibited DNA synthesis. These data indicate that CEACAM1 mediates contact inhibition of proliferation in cells that are constantly exposed to growth factors, but co-activates growth-factor-induced proliferation in cells that have been starved for growth factors; exposure to extracellular CEACAM1 ligands reverts these responses.

  8. FRET Based Quantification and Screening Technology Platform for the Interactions of Leukocyte Function-Associated Antigen-1 (LFA-1) with InterCellular Adhesion Molecule-1 (ICAM-1)

    PubMed Central

    Chakraborty, Sandeep; Núñez, David; Hu, Shih-Yang; Domingo, María Pilar; Pardo, Julian; Karmenyan, Artashes; Chiou, Arthur

    2014-01-01

    The interaction between leukocyte function-associated antigen-1(LFA-1) and intercellular adhesion molecule-1 (ICAM-1) plays a pivotal role in cellular adhesion including the extravasation and inflammatory response of leukocytes, and also in the formation of immunological synapse. However, irregular expressions of LFA-1 or ICAM-1 or both may lead to autoimmune diseases, metastasis cancer, etc. Thus, the LFA-1/ICAM-1 interaction may serve as a potential therapeutic target for the treatment of these diseases. Here, we developed one simple ‘in solution’ steady state fluorescence resonance energy transfer (FRET) technique to obtain the dissociation constant (Kd) of the interaction between LFA-1 and ICAM-1. Moreover, we developed the assay into a screening platform to identify peptides and small molecules that inhibit the LFA-1/ICAM-1 interaction. For the FRET pair, we used Alexa Fluor 488-LFA-1 conjugate as donor and Alexa Fluor 555-human recombinant ICAM-1 (D1-D2-Fc) as acceptor. From our quantitative FRET analysis, the Kd between LFA-1 and D1-D2-Fc was determined to be 17.93±1.34 nM. Both the Kd determination and screening assay were performed in a 96-well plate platform, providing the opportunity to develop it into a high-throughput assay. This is the first reported work which applies FRET based technique to determine Kd as well as classifying inhibitors of the LFA-1/ICAM-1 interaction. PMID:25032811

  9. Association between Arsenic Exposure from Drinking Water and Plasma Levels of Soluble Cell Adhesion Molecules

    PubMed Central

    Chen, Yu; Santella, Regina M.; Kibriya, Muhammad G.; Wang, Qiao; Kappil, Maya; Verret, Wendy J.; Graziano, Joseph H.; Ahsan, Habibul

    2007-01-01

    Background Epidemiologic studies of cardiovascular disease risk factors and appropriate biomarkers in populations exposed to a wide range of arsenic levels are a public health research priority. Objective We investigated the relationship between inorganic arsenic exposure from drinking water and plasma levels of soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular adhesion molecule-1 (sVCAM-1), both markers of endothelial dysfunction and vascular inflammation, in an arsenic-exposed population in Araihazar, Bangladesh. Methods The study participants included 115 individuals with arsenic-related skin lesions participating in a 2 × 2 randomized, placebo-controlled, double-blind trial of vitamin E and selenium supplementation. Arsenic exposure status and plasma levels of sICAM-1 and sVCAM-1 were assessed at baseline and after 6 months of follow-up. Results Baseline well arsenic, a long-term measure of arsenic exposure, was positively associated with baseline levels of both sICAM-1 and sVCAM-1 and with changes in the two markers over time. At baseline, for every 1-μg/L increase in well arsenic there was an increase of 0.10 ng/mL [95% confidence interval (CI), 0.00–0.20] and 0.33 ng/mL (95% CI, 0.15–0.51) in plasma sICAM-1 and sVCAM-1, respectively. Every 1-μg/L increase in well arsenic was associated with a rise of 0.11 ng/mL (95% CI, 0.01–0.22) and 0.17 ng/mL (95% CI, 0.00–0.35) in sICAM-1 and sVCAM-1 from baseline to follow-up, respectively, in spite of recent changes in urinary arsenic as well as vitamin E and selenium supplementation during the study period. Conclusions The findings indicate an effect of chronic arsenic exposure from drinking water on vascular inflammation that persists over time and also suggest a potential mechanism underlying the association between arsenic exposure and cardiovascular disease. PMID:17938729

  10. A novel role for neural cell adhesion molecule in modulating insulin signaling and adipocyte differentiation of mouse mesenchymal stem cells.

    PubMed

    Yang, Hai Jie; Xia, Yin Yan; Wang, Lei; Liu, Rui; Goh, Kim Jee; Ju, Pei Jun; Feng, Zhi Wei

    2011-08-01

    Neural cell adhesion molecule (NCAM) has recently been found on adult stem cells, but its biological significance remains largely unknown. In this study, we used bone-marrow-derived mesenchymal stem cells (MSCs) from wild-type and NCAM knockout mice to investigate the role of NCAM in adipocyte differentiation. It was demonstrated that NCAM isoforms 180 and 140 but not NCAM-120 are expressed on almost all wild-type MSCs. Upon adipogenic induction, Ncam(-/-) MSCs exhibited a marked decrease in adipocyte differentiation compared with wild-type cells. The role of NCAM in adipocyte differentiation was also confirmed in NCAM-silenced preadipocyte 3T3-L1 cells, which also had a phenotype with reduced adipogenic potential. In addition, we found that Ncam(-/-) MSCs appeared to be insulin resistant, as shown by their impaired insulin signaling cascade, such as the activation of the insulin-IGF-1 receptor, PI3K-Akt and CREB pathways. The PI3K-Akt inhibitor, LY294002, completely blocked adipocyte differentiation of MSCs, unveiling that the reduced adipogenic potential of Ncam(-/-) MSCs is due to insulin resistance as a result of loss of NCAM function. Furthermore, insulin resistance of Ncam(-/-) MSCs was shown to be associated with induction of tumor necrosis factor α (TNF-α), a key mediator of insulin resistance. Finally, we demonstrated that re-expression of NCAM-180, but not NCAM-140, inhibits induction of TNF-α and thereby improves insulin resistance and adipogenic potential of Ncam(-/-) MSCs. Our results suggest a novel role of NCAM in promoting insulin signaling and adipocyte differentiation of adult stem cells. These findings raise the possibility of using NCAM intervention to improve insulin resistance.

  11. Murine MicroRNA-214 regulates intracellular adhesion molecule (ICAM1) gene expression in genital Chlamydia muridarum infection

    PubMed Central

    Arkatkar, Tanvi; Gupta, Rishein; Li, Weidang; Yu, Jieh-Juen; Wali, Shradha; Neal Guentzel, M; Chambers, James P; Christenson, Lane K; Arulanandam, Bernard P

    2015-01-01

    The hallmark of chlamydial infection is the development of upper genital pathology in the form of hydrosalpinx and oviduct and/or tubal dilatation. Although molecular events leading to genital tissue presentation and cellular architectural remodelling are unclear, early-stage host immune responses are believed to contribute to these long-term sequelae. Recently, we reported the contribution of selected infection-associated microRNAs (miRs) in the generation of host immunity at early-stage infection (day 6 after intravaginal Chlamydia muridarum challenge in C57BL/6 mice). In this report, we describe the contribution of an infection-associated microRNA, i.e. miR-214, to host immunity. Chlamydia muridarum infection in the C57BL/6 mouse genital tract significantly down-regulated miR-214 while up-regulating intracellular adhesion molecule 1 (ICAM1) gene expression. These in vivo observations were confirmed by establishing direct regulation of ICAM-1 by miR-214 in ex vivo genital cell cultures in the presence of miR-214 mimic and inhibitor. Because, ICAM-1 contributes to recruitment of neutrophils following infection, we also demonstrated that alteration of ICAM1 by miR-214 in interleukin-17A-deficient (IL-17A−/−) mice correlated with reduction of neutrophils infiltrating genital tissue at day 6 after challenge. Additionally, these early-stage events resulted in significantly decreased genital pathology in IL-17A−/− mice compared with C57BL/6 mice. This report provides evidence for early-stage regulation of ICAM1 by microRNAs, resulting in reduction of genital pathology associated with chlamydial infection. PMID:25865776

  12. AlphaII-spectrin participates in the surface expression of cell adhesion molecule L1 and neurite outgrowth.

    PubMed

    Trinh-Trang-Tan, Marie-Marcelle; Bigot, Sylvain; Picot, Julien; Lecomte, Marie-Christine; Kordeli, Ekaterini

    2014-04-01

    AlphaII-spectrin, a basic component of the spectrin-based scaffold which organizes and stabilizes membrane microdomains in most animal cells, has been recently implicated in cell adherence and actin dynamics. Here we investigated the contribution of αΙΙ-spectrin to neuritogenesis, a highly complex cellular process which requires continuous actin cytoskeleton remodeling and cross-talk between extracellular cues and their cell surface receptors, including cell adhesion molecules. Using RNA interference-mediated gene silencing to down-regulate αΙΙ-spectrin expression in human neuroblastoma SH-SY5Y cells, we observed major changes in neurite morphology and cell shape: (1) reduced mean length and a higher number of neurites per cell; occasional long neurites were thinner and displayed abnormal adhesiveness during cell migration resulting in frequent breaks; similar persisting adhesiveness and breaks were also observed in trailing edges of cell bodies; (2) irregular polygonal cell shape in parallel with loss of cortical F-actin from neuronal cell bodies; (3) reduction in protein levels of αΙ- and βΙ-spectrins, but not βΙΙ-spectrin (4) decreased global expression of adhesion molecule L1 and spectrin-binding adapter ankyrin-B, which links L1 to the plasma membrane. Remarkably, αΙΙ-spectrin depletion affected L1 - but not NCAM - cell surface expression, and L1 clustering at growth cones. This study demonstrates that αΙΙ-spectrin is implicated in normal morphology and adhesive properties of neuron cell bodies and neurites, and in cell surface expression and organization of adhesion molecule L1. PMID:24462599

  13. The adhesion molecule PECAM-1 enhances the TGFβ-mediated inhibition of T cell function

    PubMed Central

    Newman, Debra K.; Fu, Guoping; Adams, Tamara; Cui, Weiguo; Arumugam, Vidhyalakshmi; Bluemn, Theresa; Riese, Matthew J.

    2016-01-01

    Transforming growth factor-β (TGF-β) is an immunosuppressive cytokine that inhibits the pro-inflammatory functions of T cells, and it is a major factor in abrogating T cell activity against tumors. Canonical signaling results in the activation of Smad proteins, transcription factors that regulate target gene expression. Here, we found that the cell surface molecule platelet endothelial cell adhesion molecule-1 (PECAM-1) facilitates non-canonical (Smad-independent) TGF-β signaling in T cells. Subcutaneously injected tumor cells dependent on TGF-β-mediated suppression of immunity grew more slowly in PECAM-1−/− mice than in their wild type counterparts. T cells isolated from PECAM-1−/− mice demonstrated relative insensitivity to the TGF-β-dependent inhibition of interferon- γ (IFN-γ) production, granzyme B synthesis and cellular proliferation. Similarly, human T cells lacking PECAM-1 demonstrated decreased sensitivity to TGF-β in a manner that was partially restored by re-expression of PECAM-1. Co-incubation of T cells with TGF-β and a T cell-activating antibody resulted in PECAM-1 phosphorylation on an immunoreceptor tyrosine-based inhibitory motif (ITIM) and the recruitment of the inhibitory Src homology 2 domain-containing tyrosine phosphatase-2 (SHP-2). Such stimulatory conditions also induced the co-localization of PECAM-1 with the TGF-β receptor complex as identified by co-immunoprecipitation, confocal microscopy, and proximity ligation assays. These studies indicate a role for PECAM-1 in enhancing the inhibitory functions of TGF-β in T cells and suggest that therapeutic targeting of the PECAM-1-TGF-β inhibitory axis represents a means to overcome TGF-β-dependent immunosuppression within the tumor microenvironment. PMID:26956486

  14. The adhesion molecule PECAM-1 enhances the TGF-β-mediated inhibition of T cell function.

    PubMed

    Newman, Debra K; Fu, Guoping; Adams, Tamara; Cui, Weiguo; Arumugam, Vidhyalakshmi; Bluemn, Theresa; Riese, Matthew J

    2016-03-01

    Transforming growth factor-β (TGF-β) is an immunosuppressive cytokine that inhibits the proinflammatory functions of T cells, and it is a major factor in abrogating T cell activity against tumors. Canonical TGF-β signaling results in the activation of Smad proteins, which are transcription factors that regulate target gene expression. We found that the cell surface molecule platelet endothelial cell adhesion molecule-1 (PECAM-1) facilitated noncanonical (Smad-independent) TGF-β signaling in T cells. Subcutaneously injected tumor cells that are dependent on TGF-β-mediated suppression of immunity for growth grew more slowly in PECAM-1(-/-) mice than in their wild-type counterparts. T cells isolated from PECAM-1(-/-) mice demonstrated relative insensitivity to the TGF-β-dependent inhibition of interferon-γ (IFN-γ) production, granzyme B synthesis, and cellular proliferation. Similarly, human T cells lacking PECAM-1 demonstrated decreased sensitivity to TGF-β in a manner that was partially restored by reexpression of PECAM-1. Co-incubation of T cells with TGF-β and a T cell-activating antibody resulted in PECAM-1 phosphorylation on an immunoreceptor tyrosine-based inhibitory motif (ITIM) and the recruitment of the inhibitory Src homology 2 (SH2) domain-containing tyrosine phosphatase-2 (SHP-2). Such conditions also induced the colocalization of PECAM-1 with the TGF-β receptor complex as identified by coimmunoprecipitation, confocal microscopy, and proximity ligation assays. These studies indicate a role for PECAM-1 in enhancing the inhibitory functions of TGF-β in T cells and suggest that therapeutic targeting of the PECAM-1-TGF-β inhibitory axis represents a means to overcome TGF-β-dependent immunosuppression within the tumor microenvironment. PMID:26956486

  15. R-Ras Regulates Murine T Cell Migration and Intercellular Adhesion Molecule-1 Binding.

    PubMed

    Yan, Xiaocai; Yan, Mingfei; Guo, Yihe; Singh, Gobind; Chen, Yuhong; Yu, Mei; Wang, Demin; Hillery, Cheryl A; Chan, Andrew M

    2015-01-01

    The trafficking of T-lymphocytes to peripheral draining lymph nodes is crucial for mounting an adaptive immune response. The role of chemokines in the activation of integrins via Ras-related small GTPases has been well established. R-Ras is a member of the Ras-subfamily of small guanosine-5'-triphosphate-binding proteins and its role in T cell trafficking has been investigated in R-Ras null mice (Rras-/-). An examination of the lymphoid organs of Rras-/- mice revealed a 40% reduction in the cellularity of the peripheral lymph nodes. Morphologically, the high endothelial venules of Rras-/- mice were more disorganized and less mature than those of wild-type mice. Furthermore, CD4+ and CD8+ T cells from Rras-/- mice had approximately 42% lower surface expression of L-selectin/CD62L. These aberrant peripheral lymph node phenotypes were associated with proliferative and trafficking defects in Rras-/- T cells. Furthermore, R-Ras could be activated by the chemokine, CCL21. Indeed, Rras-/- T cells had approximately 14.5% attenuation in binding to intercellular adhesion molecule 1 upon CCL21 stimulation. Finally, in a graft-versus host disease model, recipient mice that were transfused with Rras-/- T cells showed a significant reduction in disease severity when compared with mice transplanted with wild-type T cells. These findings implicate a role for R-Ras in T cell trafficking in the high endothelial venules during an effective immune response. PMID:26710069

  16. Genetic polymorphisms of cell adhesion molecules in Behcet’s disease in a Chinese Han population

    PubMed Central

    Zheng, Minming; Zhang, Lijun; Yu, Hongsong; Hu, Jiayue; Cao, Qingfeng; Huang, Guo; Huang, Yang; Yuan, Gangxiang; Kijlstra, Aize; Yang, Peizeng

    2016-01-01

    Cell adhesion molecules (CAMs) are involved in various immune-mediated diseases. This study was conducted to investigate the association of single nucleotide polymorphisms (SNPs) of CAMs with Behçet’s disease (BD) in a Chinese Han population. A two-stage association study was carried out in 1149 BD patients and 2107 normal controls. Genotyping of 43 SNPs was performed using MassARRAY System (Sequenom), polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and TaqMan SNP assays. The expression of CD6 and CD11c was examined by real-time PCR and cytokine production was measured by ELISA. A significantly higher frequency of the CT genotype, and a lower frequency of the CC genotype and C allele of CD6 rs11230563 were observed in BD as compared with controls. Analysis of CD11c rs2929 showed that patients with BD had a significantly higher frequency of the GG genotype and G allele, and a lower frequency of the AG genotype as compared with controls. Functional experiments showed an increased CD11c expression and increased production of TNF-α and IL-1beta by LPS stimulated PBMCs in GG carriers of CD11c rs2929 compared to AA/AG carriers. Our study provides evidence that CD6 and CD11c are involved in the susceptibility to BD in a Chinese Han population. PMID:27108704

  17. Down syndrome cell adhesion molecule 1: testing for a role in insect immunity, behaviour and reproduction.

    PubMed

    Peuß, Robert; Wensing, Kristina U; Woestmann, Luisa; Eggert, Hendrik; Milutinović, Barbara; Sroka, Marlene G U; Scharsack, Jörn P; Kurtz, Joachim; Armitage, Sophie A O

    2016-04-01

    Down syndrome cell adhesion molecule 1 (Dscam1) has wide-reaching and vital neuronal functions although the role it plays in insect and crustacean immunity is less well understood. In this study, we combine different approaches to understand the roles that Dscam1 plays in fitness-related contexts in two model insect species. Contrary to our expectations, we found no short-term modulation of Dscam1 gene expression after haemocoelic or oral bacterial exposure in Tribolium castaneum, or after haemocoelic bacterial exposure in Drosophila melanogaster. Furthermore, RNAi-mediated Dscam1 knockdown and subsequent bacterial exposure did not reduce T. castaneum survival. However, Dscam1 knockdown in larvae resulted in adult locomotion defects, as well as dramatically reduced fecundity in males and females. We suggest that Dscam1 does not always play a straightforward role in immunity, but strongly influences behaviour and fecundity. This study takes a step towards understanding more about the role of this intriguing gene from different phenotypic perspectives. PMID:27152227

  18. L1 CELL ADHESION MOLECULE SIGNALING IS INHIBITED BY ETHANOL IN VIVO

    PubMed Central

    Littner, Yoav; Tang, Ningfeng; He, Min; Bearer, Cynthia F.

    2012-01-01

    Background Fetal alcohol spectrum disorder is an immense public health problem. In vitro studies support the hypothesis that L1 cell adhesion molecule (L1) is a target for ethanol developmental neurotoxicity. L1 is critical for the development of the central nervous system. It functions through signal transduction leading to phosphorylation and dephosphorylation of tyrosines on its cytoplasmic domain. The function of L1 is also dependent on trafficking through lipid rafts. Our hypothesis is that L1 is a target for ethanol neurotoxicity in vivo. Our objective is to demonstrate changes in L1 phosphorylation/dephosphorylation and lipid raft association in vivo. Methods Rat pups on postnatal day 6 are administered 4.5, 5.25 and 6 g/kg of ethanol divided into 2 doses 2 hours apart, then sacrificed. Cerebella are rapidly frozen for assay. Blood is analyzed for blood ethanol concentration. L1 tyrosine phosphorylation is determined by immunoprecipitation and dephosphorylation of tyrosine 1176 determined by immunoblot. Lipid rafts are isolated by sucrose density gradient and the distribution of L1 in lipid rafts is determined. Results Ethanol at all doses reduced the relative amount of Y1176 dephosphorylation as well as the relative amount of L1 phosphorylated on other tyrosines. The proportion of L1 present in lipid rafts is significantly increased in pups who received 6 g/kg ethanol compared to intubated controls. Conclusions L1 is a target for ethanol developmental neurotoxicity in vivo. PMID:23050935

  19. Different patterns of soluble adhesion molecules in systemic and cutaneous lupus erythematosus.

    PubMed

    Nyberg, F; Acevedo, F; Stephansson, E

    1997-10-01

    Circulating isoforms of cellular adhesion molecules (CAMs) have been described recently, and elevated levels of certain sCAMs have been reported in various inflammatory diseases such as systemic lupus erythematosus (SLE). There are previously no reports on sCAMs in cutaneous LE. Sera from 61 patients with LE: systemic (SLE: n=24), chronic cutaneous (discoid LE, DLE: n= 19) or subacute cutaneous (SCLE: n=8), chronic biologically false positive (CBFP) reactors for syphilis (n= 10) and 32 controls were examined for sICAM-1, sVCAM-1 and sE-Selectin with specific ELISA kits. Protocol forms were reviewed. We found significantly elevated levels of sE-Selectin in patients with DLE and widespread cutaneous symptoms, and a correlation between active cutaneous disease as well as polymorphous light eruption (PLE) and elevated levels of sE-Selectin. In contrast, patients with systemic LE did not have elevated levels of sE-Selectin, but in concordance with earlier reports, sICAM-1 and sVCAM-1 levels were elevated compared to controls in SLE, as well as in SCLE patients, which has not been reported previously. Since activated endothelial cells are the only source for E-Selectin, the elevated sE-Selectin level in patients with widespread and active cutaneous disease suggests a more important role for endothelial cells in the pathogenesis of cutaneous LE than previously assumed.

  20. NK cells, displaying early activation, cytotoxicity and adhesion molecules, are associated with mild dengue disease

    PubMed Central

    Azeredo, E L; De Oliveira-Pinto, L M; Zagne, S M; Cerqueira, D I S; Nogueira, R M R; Kubelka, C F

    2006-01-01

    During the innate immune response against infections, Natural Killer (NK) cells are as important effector cells as are Cytotoxic T lymphocytes (CTL) generated after antigenic stimulation in the adaptative response. NK cells increase in numbers, after viral infection or vaccination. We investigated the NK cell and CD8 T lymphocyte status in 55 dengue infected patients. The NK (CD56+CD3−) and CD56+ T cell (CD56+CD3+) rates rise during the acute phase of disease. The majority of NK cells from dengue patients display early markers for activation (CD69, HLA-DR, and CD38) and cell adhesion molecules (CD44, CD11a) during the acute phase of disease. The intracellular cytotoxic granule, TIA-1, is also up-regulated early in NK cells. Most of these markers appear also on CD8+ T lymphocytes but during the late acute phase. Circulating IL-15 is elevated in a significant number of patients during early acute infection and its values were statistically correlated with NK frequencies and cytotoxic markers on NKs. We have therefore shown that dengue virus infection is very likely stimulating a cytotoxic response that may be efficient in controlling the virus in synergism with CD8+ T lymphocytes. Interestingly, the heightened CD56+CD3−, CD56+CD3+, CD56+TIA-1+ and CD56+CD11a+ cell rates are associated with mild dengue clinical manifestations and might indicate a good prognosis of the disease. PMID:16412060

  1. Down syndrome cell adhesion molecule 1: testing for a role in insect immunity, behaviour and reproduction

    PubMed Central

    Wensing, Kristina U.; Eggert, Hendrik; Scharsack, Jörn P.

    2016-01-01

    Down syndrome cell adhesion molecule 1 (Dscam1) has wide-reaching and vital neuronal functions although the role it plays in insect and crustacean immunity is less well understood. In this study, we combine different approaches to understand the roles that Dscam1 plays in fitness-related contexts in two model insect species. Contrary to our expectations, we found no short-term modulation of Dscam1 gene expression after haemocoelic or oral bacterial exposure in Tribolium castaneum, or after haemocoelic bacterial exposure in Drosophila melanogaster. Furthermore, RNAi-mediated Dscam1 knockdown and subsequent bacterial exposure did not reduce T. castaneum survival. However, Dscam1 knockdown in larvae resulted in adult locomotion defects, as well as dramatically reduced fecundity in males and females. We suggest that Dscam1 does not always play a straightforward role in immunity, but strongly influences behaviour and fecundity. This study takes a step towards understanding more about the role of this intriguing gene from different phenotypic perspectives. PMID:27152227

  2. Junctional Adhesion Molecule A Promotes Epithelial Tight Junction Assembly to Augment Lung Barrier Function

    PubMed Central

    Mitchell, Leslie A.; Ward, Christina; Kwon, Mike; Mitchell, Patrick O.; Quintero, David A.; Nusrat, Asma; Parkos, Charles A.; Koval, Michael

    2016-01-01

    Epithelial barrier function is maintained by tight junction proteins that control paracellular fluid flux. Among these proteins is junctional adhesion molecule A (JAM-A), an Ig fold transmembrane protein. To assess JAM-A function in the lung, we depleted JAM-A in primary alveolar epithelial cells using shRNA. In cultured cells, loss of JAM-A caused an approximately 30% decrease in transepithelial resistance, decreased expression of the tight junction scaffold protein zonula occludens 1, and disrupted junctional localization of the structural transmembrane protein claudin-18. Consistent with findings in other organs, loss of JAM-A decreased β1 integrin expression and impaired filamentous actin formation. Using a model of mild systemic endoxotemia induced by i.p. injection of lipopolysaccharide, we report that JAM-A−/− mice showed increased susceptibility to pulmonary edema. On injury, the enhanced susceptibility of JAM-A−/− mice to edema correlated with increased, transient disruption of claudin-18, zonula occludens 1, and zonula occludens 2 localization to lung tight junctions in situ along with a delay in up-regulation of claudin-4. In contrast, wild-type mice showed no change in lung tight junction morphologic features in response to mild systemic endotoxemia. These findings support a key role of JAM-A in promoting tight junction homeostasis and lung barrier function by coordinating interactions among claudins, the tight junction scaffold, and the cytoskeleton. PMID:25438062

  3. Myelin Basic Protein Cleaves Cell Adhesion Molecule L1 and Improves Regeneration After Injury.

    PubMed

    Lutz, David; Kataria, Hardeep; Kleene, Ralf; Loers, Gabriele; Chaudhary, Harshita; Guseva, Daria; Wu, Bin; Jakovcevski, Igor; Schachner, Melitta

    2016-07-01

    Myelin basic protein (MBP) is a serine protease that cleaves neural cell adhesion molecule L1 and generates a transmembrane L1 fragment which facilitates L1-dependent functions in vitro, such as neurite outgrowth, neuronal cell migration and survival, myelination by Schwann cells as well as Schwann cell proliferation, migration, and process formation. Ablation and blocking of MBP or disruption of its proteolytic activity by mutation of a proteolytically active serine residue abolish L1-dependent cellular responses. In utero injection of adeno-associated virus encoding proteolytically active MBP into MBP-deficient shiverer mice normalizes differentiation, myelination, and synaptogenesis in the developing postnatal spinal cord, in contrast to proteolytically inactive MBP. Application of active MBP to the injured wild-type spinal cord and femoral nerve augments levels of a transmembrane L1 fragment, promotes remyelination, and improves functional recovery after injury. Application of MBP antibody impairs recovery. Virus-mediated expression of active MBP in the lesion site after spinal cord injury results in improved functional recovery, whereas injection of virus encoding proteolytically inactive MBP fails to do so. The present study provides evidence for a novel L1-mediated function of MBP in the developing spinal cord and in the injured adult mammalian nervous system that leads to enhanced recovery after acute trauma.

  4. Annexin A2 Acts as an Adhesion Molecule on the Endometrial Epithelium during Implantation in Mice

    PubMed Central

    Lee, Kai-Fai; Chiu, Philip C. N.; Pang, Ronald T. K.; Ng, Ernest H. Y.; Yeung, William S. B.

    2015-01-01

    To determine the function of Annexin A2 (Axna2) in mouse embryo implantation in vivo, experimental manipulation of Axna2 activities was performed in mouse endometrial tissue in vivo and in vitro. Histological examination of endometrial tissues was performed throughout the reproduction cycle and after steroid treatment. Embryo implantation was determined after blockage of the Axna2 activities by siRNA or anti-Axna2 antibody. The expression of Axna2 immunoreactivies in the endometrial luminal epithelium changed cyclically in the estrus cycle and was upregulated by estrogen. After nidatory estrogen surge, there was a concentration of Axna2 immunoreactivities at the interface between the implanting embryo and the luminal epithelium. The phenomenon was likely to be induced by the implanting embryos as no such concentration of signal was observed in the inter-implantation sites and in pseudopregnancy. Knockdown of Axna2 by siRNA reduced attachment of mouse blastocysts onto endometrial tissues in vitro. Consistently, the number of implantation sites was significantly reduced after infusion of anti-Axna2 antibody into the uterine cavity. Steroids and embryos modulate the expression of Axna2 in the endometrial epithelium. Axna2 may function as an adhesion molecule during embryo implantation in mice. PMID:26444699

  5. Annexin A2 Acts as an Adhesion Molecule on the Endometrial Epithelium during Implantation in Mice.

    PubMed

    Wang, Bing; Ye, Tian-Min; Lee, Kai-Fai; Chiu, Philip C N; Pang, Ronald T K; Ng, Ernest H Y; Yeung, William S B

    2015-01-01

    To determine the function of Annexin A2 (Axna2) in mouse embryo implantation in vivo, experimental manipulation of Axna2 activities was performed in mouse endometrial tissue in vivo and in vitro. Histological examination of endometrial tissues was performed throughout the reproduction cycle and after steroid treatment. Embryo implantation was determined after blockage of the Axna2 activities by siRNA or anti-Axna2 antibody. The expression of Axna2 immunoreactivies in the endometrial luminal epithelium changed cyclically in the estrus cycle and was upregulated by estrogen. After nidatory estrogen surge, there was a concentration of Axna2 immunoreactivities at the interface between the implanting embryo and the luminal epithelium. The phenomenon was likely to be induced by the implanting embryos as no such concentration of signal was observed in the inter-implantation sites and in pseudopregnancy. Knockdown of Axna2 by siRNA reduced attachment of mouse blastocysts onto endometrial tissues in vitro. Consistently, the number of implantation sites was significantly reduced after infusion of anti-Axna2 antibody into the uterine cavity. Steroids and embryos modulate the expression of Axna2 in the endometrial epithelium. Axna2 may function as an adhesion molecule during embryo implantation in mice.

  6. Homocysteine, circulating vascular cell adhesion molecule and carotid atherosclerosis in postmenopausal vegetarian women and omnivores.

    PubMed

    Su, Ta-Chen; Jeng, Jiann-Shing; Wang, Jung-Der; Torng, Pao-Ling; Chang, Sue-Joan; Chen, Chen-Fang; Liau, Chiau-Suong

    2006-02-01

    Since the adoption of vegetarian diets as a healthy lifestyle has become popular, the cardiovascular effects of long-term vegetarianism need to be explored. The present study aimed to compare the presence and severity of carotid atherosclerosis (CA), and the blood levels of Vitamin B12, homocysteine (Hcy) and soluble vascular cell adhesion molecule-1 (sVCAM-1) between 57 healthy postmenopausal vegetarians and 61 age-matched omnivores. Carotid atherosclerosis, as measured by ultrasound, was found to be of no significant difference between the two groups. Yet, fasting blood glucose, low-density lipoprotein cholesterol, and Vitamin B12 were significantly lower, while Hcy and sVCAM-1 were higher in the vegetarians as comparing with the omnivores. Multivariate regression analysis showed that the level of Vitamin B12 was negatively associated with the level of Hcy. Vegetarianism itself and Hcy level were significantly associated with sVCAM-1 level in univariate analysis; however, after adjustment for covariates, we identified age but not vegetarianism as the determinant of sVCAM-1 level. Multiple linear regression analysis identified age and systolic blood pressure, but not vegetarianism, as determinants of common carotid artery IMT. In conclusion, there was no significant difference in CA between apparently healthy postmenopausal vegetarians and omnivores. The findings of elevated Hcy in vegetarians indicate the importance of prevention of Vitamin B12 deficiency.

  7. The Prion Protein Controls Polysialylation of Neural Cell Adhesion Molecule 1 during Cellular Morphogenesis

    PubMed Central

    Mehrabian, Mohadeseh; Brethour, Dylan; Wang, Hansen; Xi, Zhengrui; Rogaeva, Ekaterina; Schmitt-Ulms, Gerold

    2015-01-01

    Despite its multi-faceted role in neurodegenerative diseases, the physiological function of the prion protein (PrP) has remained elusive. On the basis of its evolutionary relationship to ZIP metal ion transporters, we considered that PrP may contribute to the morphogenetic reprogramming of cells underlying epithelial-to-mesenchymal transitions (EMT). Consistent with this hypothesis, PrP transcription increased more than tenfold during EMT, and stable PrP-deficient cells failed to complete EMT in a mammalian cell model. A global comparative proteomics analysis identified the neural cell adhesion molecule 1 (NCAM1) as a candidate mediator of this impairment, which led to the observation that PrP-deficient cells fail to undergo NCAM1 polysialylation during EMT. Surprisingly, this defect was caused by a perturbed transcription of the polysialyltransferase ST8SIA2 gene. Proteomics data pointed toward β-catenin as a transcriptional regulator affected in PrP-deficient cells. Indeed, pharmacological blockade or siRNA-based knockdown of β-catenin mimicked PrP-deficiency in regards to NCAM1 polysialylation. Our data established the existence of a PrP-ST8SIA2-NCAM signaling loop, merged two mature fields of investigation and offer a simple model for explaining phenotypes linked to PrP. PMID:26288071

  8. Myelin Basic Protein Cleaves Cell Adhesion Molecule L1 and Improves Regeneration After Injury.

    PubMed

    Lutz, David; Kataria, Hardeep; Kleene, Ralf; Loers, Gabriele; Chaudhary, Harshita; Guseva, Daria; Wu, Bin; Jakovcevski, Igor; Schachner, Melitta

    2016-07-01

    Myelin basic protein (MBP) is a serine protease that cleaves neural cell adhesion molecule L1 and generates a transmembrane L1 fragment which facilitates L1-dependent functions in vitro, such as neurite outgrowth, neuronal cell migration and survival, myelination by Schwann cells as well as Schwann cell proliferation, migration, and process formation. Ablation and blocking of MBP or disruption of its proteolytic activity by mutation of a proteolytically active serine residue abolish L1-dependent cellular responses. In utero injection of adeno-associated virus encoding proteolytically active MBP into MBP-deficient shiverer mice normalizes differentiation, myelination, and synaptogenesis in the developing postnatal spinal cord, in contrast to proteolytically inactive MBP. Application of active MBP to the injured wild-type spinal cord and femoral nerve augments levels of a transmembrane L1 fragment, promotes remyelination, and improves functional recovery after injury. Application of MBP antibody impairs recovery. Virus-mediated expression of active MBP in the lesion site after spinal cord injury results in improved functional recovery, whereas injection of virus encoding proteolytically inactive MBP fails to do so. The present study provides evidence for a novel L1-mediated function of MBP in the developing spinal cord and in the injured adult mammalian nervous system that leads to enhanced recovery after acute trauma. PMID:26081148

  9. The Prion Protein Controls Polysialylation of Neural Cell Adhesion Molecule 1 during Cellular Morphogenesis.

    PubMed

    Mehrabian, Mohadeseh; Brethour, Dylan; Wang, Hansen; Xi, Zhengrui; Rogaeva, Ekaterina; Schmitt-Ulms, Gerold

    2015-01-01

    Despite its multi-faceted role in neurodegenerative diseases, the physiological function of the prion protein (PrP) has remained elusive. On the basis of its evolutionary relationship to ZIP metal ion transporters, we considered that PrP may contribute to the morphogenetic reprogramming of cells underlying epithelial-to-mesenchymal transitions (EMT). Consistent with this hypothesis, PrP transcription increased more than tenfold during EMT, and stable PrP-deficient cells failed to complete EMT in a mammalian cell model. A global comparative proteomics analysis identified the neural cell adhesion molecule 1 (NCAM1) as a candidate mediator of this impairment, which led to the observation that PrP-deficient cells fail to undergo NCAM1 polysialylation during EMT. Surprisingly, this defect was caused by a perturbed transcription of the polysialyltransferase ST8SIA2 gene. Proteomics data pointed toward β-catenin as a transcriptional regulator affected in PrP-deficient cells. Indeed, pharmacological blockade or siRNA-based knockdown of β-catenin mimicked PrP-deficiency in regards to NCAM1 polysialylation. Our data established the existence of a PrP-ST8SIA2-NCAM signaling loop, merged two mature fields of investigation and offer a simple model for explaining phenotypes linked to PrP. PMID:26288071

  10. Polysialic Acid Directs Tumor Cell Growth by Controlling Heterophilic Neural Cell Adhesion Molecule Interactions

    PubMed Central

    Seidenfaden, Ralph; Krauter, Andrea; Schertzinger, Frank; Gerardy-Schahn, Rita; Hildebrandt, Herbert

    2003-01-01

    Polysialic acid (PSA), a carbohydrate polymer attached to the neural cell adhesion molecule (NCAM), promotes neural plasticity and tumor malignancy, but its mode of action is controversial. Here we establish that PSA controls tumor cell growth and differentiation by interfering with NCAM signaling at cell-cell contacts. Interactions between cells with different PSA and NCAM expression profiles were initiated by enzymatic removal of PSA and by ectopic expression of NCAM or PSA-NCAM. Removal of PSA from the cell surface led to reduced proliferation and activated extracellular signal-regulated kinase (ERK), inducing enhanced survival and neuronal differentiation of neuroblastoma cells. Blocking with an NCAM-specific peptide prevented these effects. Combinatorial transinteraction studies with cells and membranes with different PSA and NCAM phenotypes revealed that heterophilic NCAM binding mimics the cellular responses to PSA removal. In conclusion, our data demonstrate that PSA masks heterophilic NCAM signals, having a direct impact on tumor cell growth. This provides a mechanism for how PSA may promote the genesis and progression of highly aggressive PSA-NCAM-positive tumors. PMID:12897159

  11. Bilirubin acts as an endogenous regulator of inflammation by disrupting adhesion molecule-mediated leukocyte migration

    PubMed Central

    Vogel, Megan E.; Zucker, Stephen D.

    2016-01-01

    There is a growing body of evidence that bilirubin, which is generated during the physiological breakdown of heme, exerts potent anti-inflammatory effects. Previous work by our group suggests that bilirubin is able to suppress inflammatory responses by preventing the migration of leukocytes into target tissues through disruption of vascular cell adhesion molecule-1 (VCAM-1)-dependent cell signaling. As VCAM-1 is an important mediator of tissue injury in the dextran sodium sulfate (DSS) murine model of inflammatory colitis, we examined whether bilirubin prevents colonic injury in DSS-treated mice. As anticipated, bilirubin-treated animals manifested significantly less colonic injury and reduced infiltration of inflammatory cells into colon tissues. We further observed that bilirubin administration was associated with a reduced number of eosinophils and monocytes in the small intestine, with a corresponding increase in peripheral blood eosinophilia, regardless of whether mice received DSS. These findings suggest that bilirubin impairs the normal migration of eosinophils into intestinal tissues, as supported by in vitro experiments showing that bilirubin blocks the VCAM-1-dependent movement of Jurkat cells across human endothelial cell monolayers. Taken together, our findings support that bilirubin ameliorates DSS-induced colitis and disrupts the physiological trafficking of leukocytes to the intestine by preventing transmigration across the vascular endothelium, potentially through the inhibition VCAM-1-mediated signaling. Our findings raise the possibility that bilirubin functions as an endogenous regulator of inflammatory responses. PMID:26925435

  12. Functional studies of truncated soluble intercellular adhesion molecule 1 expressed in Escherichia coli.

    PubMed Central

    Martin, S; Martin, A; Staunton, D E; Springer, T A

    1993-01-01

    We have expressed in Escherichia coli the two N-terminal immunoglobulin (Ig)-like domains of the intercellular adhesion molecule 1 (ICAM-1). The first 188 residues of ICAM-1 were expressed with an N-terminal methionine (MP188) or as a maltose-binding fusion protein which was cleaved with factor Xa (XP188). After refolding, both MP188 and XP188 were active in binding to the leukocyte integrin lymphocyte function-associated antigen 1, which has previously been shown to bind to the N-terminal Ig domain of ICAM-1. The major group of rhinoviruses and malaria-infected erythrocytes bind to distinct sites within the first Ig-like domain of ICAM-1. Both MP188 and XP188 bound to malaria-infected erythrocytes; however, only XP188 inhibited human rhinovirus plaque formation. A product (MdQ1P188) with the initiation methionine fused to residue 2, i.e., with glutamine 1 deleted, inhibited plaque formation. MdQ1P188 was able to induce a conformational change of the virus capsid as shown by conversion of 149S particles to 85S particles, whereas MP188 had no effect. These results show that functionally active fragments of ICAM-1 can be produced in E. coli, that glycosylation is not required for ligand binding, and that the N-terminal residue of ICAM-1 is proximal to or part of the human rhinovirus-binding site. Images PMID:8101071

  13. Biosynthesis of the neural cell adhesion molecule: characterization of polypeptide C

    PubMed Central

    1985-01-01

    The biosynthesis of the neural cell adhesion molecule (N-CAM) was studied in primary cultures of rat cerebral glial cells, cerebellar granule neurons, and skeletal muscle cells. The three cell types produced different N-CAM polypeptide patterns. Glial cells synthesized a 135,000 Mr polypeptide B and a 115,000 Mr polypeptide C, whereas neurons expressed a 200,000 Mr polypeptide A as well as polypeptide B. Skeletal muscle cells produced polypeptide B. The polypeptides synthesized by the three cell types were immunochemically identical. The membrane association of polypeptide C was investigated with methods that distinguish peripheral and integral membrane proteins. Polypeptide C was found to be a peripheral membrane protein, whereas polypeptides A and B were integral membrane proteins with cytoplasmic domains of approximately 50,000 and approximately 25,000 Mr, respectively. The affinity of the membrane binding of polypeptide C increased during postnatal development. The posttranslational modifications of polypeptide C were investigated in glial cell cultures, and it was found to be N-linked glycosylated and sulfated. PMID:4066759

  14. Role of Intercellular Adhesion Molecule-1 in Radiation-Induced Brain Injury

    SciTech Connect

    Wu, K.-L.; Tu Ba; Li Yuqing; Wong, C. Shun

    2010-01-15

    Purpose: To determine the role of intercellular adhesion molecule-1 (ICAM-1) in the pathogenesis of brain injury after irradiation (IR). Methods and Materials: We assessed the expression of ICAM-1 in mouse brain after cranial IR and determined the histopathologic and behavioral changes in mice that were either wildtype (+/+) or knockout (-/-) of the ICAM-1 gene after IR. Results: There was an early dose-dependent increase in ICAM-1 mRNA and protein expression after IR. Increased ICAM-1 immunoreactivity was observed in endothelia and glia of ICAM-1+/+ mice up to 8 months after IR. ICAM-1-/- mice showed no expression. ICAM-1+/+ and ICAM-1-/- mice showed similar vascular abnormalities at 2 months after 10-17 Gy, and there was evidence for demyelination and inhibition of hippocampal neurogenesis at 8 months after 10 Gy. After 10 Gy, irradiated ICAM-1+/+ and ICAM-1-/- mice showed similar behavioral changes at 2-6 months in open field, light-dark chamber, and T-maze compared with age-matched genotype controls. Conclusion: There is early and late upregulation of ICAM-1 in the vasculature and glia of mouse brain after IR. ICAM-1, however, does not have a causative role in the histopathologic injury and behavioral dysfunction after moderate single doses of cranial IR.

  15. CHLORHEXIDINE INHIBITS L1 CELL ADHESION MOLECULE MEDIATED NEURITE OUTGROWTH IN VITRO

    PubMed Central

    Milstone, Aaron M.; Bamford, Penny; Aucott, Susan W.; Tang, Ningfeng; White, Kimberly R.; Bearer, Cynthia F.

    2013-01-01

    Background Chlorhexidine is a skin disinfectant that reduces skin and mucous membrane bacterial colonization and inhibits organism growth. Despite numerous studies assessing chlorhexidine safety in term infants, residual concerns have limited its use in hospitalized neonates, especially low birth weight preterm infants. The aim of this study was to assess the potential neurotoxicity of chlorhexidine on the developing central nervous system using a well-established in vitro model of neurite outgrowth that includes laminin and L1 cell adhesion molecule (L1) as neurite outgrowth promoting substrates. Methods Cerebellar granule neurons are plated on either poly L-lysine, L1 or laminin. Chlorhexidine, hexachlorophene or their excipients are added to the media. Neurons are grown for 24 h, then fixed and neurite length measured. Results Chlorhexidine significantly reduced the length of neurites grown on L1 but not laminin. Chlorhexidine concentrations as low as 125 ng/ml statistically significantly reduced neurite length on L1. Hexachlorophene did not affect neurite length. Conclusion Chlorhexidine at concentrations detected in the blood following topical applications in preterm infants specifically inhibited L1 mediated neurite outgrowth of cerebellar granule neurons. It is now vital to determine whether the blood brain barrier is permeable to chlorhexidine in preterm infants. PMID:24126818

  16. Alternatively spliced variants of the cell adhesion molecule CD44 and tumour progression in colorectal cancer.

    PubMed Central

    Gotley, D. C.; Fawcett, J.; Walsh, M. D.; Reeder, J. A.; Simmons, D. L.; Antalis, T. M.

    1996-01-01

    Increased expression of alternatively spliced variants of the CD44 family of cell adhesion molecules has been associated with tumour metastasis. In the present study, expression of alternatively spliced variants of CD44 and their cellular distribution have been investigated in human colonic tumours and in the corresponding normal mucosa, in addition to benign adenomatous polyps. The expression of CD44 alternatively spliced variants has been correlated with tumour progression according to Dukes' histological stage. CD44 variant expression was determined by immunohistochemisty using monoclonal antibodies directed against specific CD44 variant domains together with RT-PCR analysis of CD44 variant mRNA expression in the same tissue specimens. We demonstrate that as well as being expressed in colonic tumour cells, the full range of CD44 variants, CD44v2-v10, are widely expressed in normal colonic crypt epithelium, predominantly in the crypt base. CD44v6, the epitope which is most commonly associated with tumour progression and metastasis, was not only expressed by many benign colonic tumours, but was expressed as frequently in normal basal crypt epithelium as in malignant colonic tumour cells, and surprisingly, was even absent from some metastatic colorectal tumours. Expression of none of the CD44 variant epitopes was found to be positively correlated with tumour progression or with colorectal tumour metastasis to the liver, results which are inconsistent with a role for CD44 variants as indicators of colonic cancer progression. Images Figure 2 Figure 3 Figure 5 Figure 6 PMID:8695347

  17. Polymorphisms in the intercellular adhesion molecule 1 gene and cancer risk: a meta-analysis

    PubMed Central

    Tang, Weifeng; Wang, Yafeng; Chen, Yuanmei; Gu, Haiyong; Chen, Shuchen; Kang, Mingqiang

    2015-01-01

    Objectives: The correlation between intercellular adhesion molecule 1 (ICAM-1) common polymorphisms (rs5498 A>G and rs3093030 C>T) and cancer susceptibility has been explored in various ethnic groups and different cancer types; however, these investigations have yielded contradictory results. To address the relationship more precisely, we performed this meta-analysis. Design and methods: EmBase, PubMed and China National Knowledge Infrastructure (CNKI) databases were searched by two authors independently for eligible publications before April 8, 2015. Random-effects or fixed-effects model was harnessed to calculate the pooled odds ratios (ORs) and 95% confidence intervals (CIs) when appropriate. Results: The result suggested that the ICAM-1 rs5498 A>G polymorphism is not associated with cancer susceptibility in overall cancer. In a stratified analysis by ethnicity, a significant increased cancer risk was identified among Asians, but the inverse association was found among Caucasians. In a stratified analysis by cancer type, ICAM-1 rs5498 A>G polymorphism was associated with a significantly increased risk of oral cancer, but with protection from colorectal cancer and melanoma. ICAM-1 rs3093030 C>T polymorphism is not correlated with cancer susceptibility. Conclusions: In summary, this meta-analysis highlights that the ICAM-1 rs5498 A>G polymorphism probably contributes to decreased susceptibility to cancer, especially in Caucasians, in melanoma and colorectal cancer subgroup, but it may be a risk factor for oral cancer and Asians. PMID:26550112

  18. Origin of metazoan adhesion molecules and adhesion receptors as deduced from cDNA analyses in the marine sponge Geodia cydonium: a review.

    PubMed

    Müller, W E

    1997-09-01

    The phylogenetic relationships of the kingdom Animalia (Metazoa) have long been questioned. Whether the lowest eukaryotic multicellular organisms, the metazoan phylum Porifera (sponges), independently evolved multicellularity from a separate protist lineage (polyphyly of animals) or whether they were derived from the same protist group as the other animal phyla (monophyly) remains unclear. Analyses of the genes that are typical for multicellularity, e.g. those coding for adhesion molecules (galectin) and adhesion receptors (receptor tyrosine kinase, integrin receptor, receptors featuring scavenger receptor cysteine-rich domains) or elements involved in signal transduction pathways (G-proteins, Ser/Thr protein kinases), especially from the marine sponge Geodia cydonium, indicate that all animals, including sponges, are of monophyletic origin. PMID:9232818

  19. Testing synthetic amyloid-β aggregation inhibitor using single molecule atomic force spectroscopy.

    PubMed

    Hane, Francis T; Lee, Brenda Y; Petoyan, Anahit; Rauk, Arvi; Leonenko, Zoya

    2014-04-15

    Alzheimer's disease is a neurodegenerative disease with no known cure and few effective treatment options. The principal neurotoxic agent is an oligomeric form of the amyloid-β peptide and one of the treatment options currently being studied is the inhibition of amyloid aggregation. In this work, we test a novel pseudopeptidic aggregation inhibitor designated as SG1. SG1 has been designed to bind at the amyloid-β self-recognition site and prevent amyloid-β from misfolding into β sheet. We used atomic force spectroscopy, a nanoscale measurement technique, to quantify the binding forces between two single amyloid peptide molecules. For the first time, we demonstrate that single molecule atomic force spectroscopy can be used to assess the effectiveness of amyloid aggregation inhibitors by measuring the experimental yield of binding and can potentially be used as a screening technique for quick testing of efficacy of inhibitor drugs for amyloid aggregation.

  20. Molecular Dynamics simulations of Inhibitor of Apoptosis Proteins and identification of potential small molecule inhibitors.

    PubMed

    Jayakumar, Jayanthi; Anishetty, Sharmila

    2014-05-01

    Chemotherapeutic resistance due to over expression of Inhibitor of Apoptosis Proteins (IAPs) XIAP, survivin and livin has been observed in various cancers. In the current study, Molecular Dynamics (MD) simulations were carried out for all three IAPs and a common ligand binding scaffold was identified. Further, a novel sequence based motif specific to these IAPs was designed. SMAC is an endogenous inhibitor of IAPs. Screening of ChemBank for compounds similar to lead SMAC-non-peptidomimetics yielded a cemadotin related compound NCIMech_000654. Cemadotin is a derivative of natural anti-tumor peptide dolastatin-15; hence these compounds were docked against all three IAPs. Based on our analysis, we propose that NCIMech_000654/dolastatin-15/cemadotin derivatives may be investigated for their potential in inhibiting XIAP, survivin and livin.

  1. Synthetic Small Molecule Inhibitors of Hh Signaling As Anti-Cancer Chemotherapeutics

    PubMed Central

    Maschinot, C.A.; Pace, J.R.; Hadden, M.K.

    2016-01-01

    The hedgehog (Hh) pathway is a developmental signaling pathway that is essential to the proper embryonic development of many vertebrate systems. Dysregulation of Hh signaling has been implicated as a causative factor in the development and progression of several forms of human cancer. As such, the development of small molecule inhibitors of Hh signaling as potential anti-cancer chemotherapeutics has been a major area of research interest in both academics and industry over the past ten years. Through these efforts, synthetic small molecules that target multiple components of the Hh pathway have been identified and advanced to preclinical or clinical development. The goal of this review is to provide an update on the current status of several synthetic small molecule Hh pathway inhibitors and explore the potential of several recently disclosed inhibitory scaffolds. PMID:26310919

  2. Activated leukocyte cell adhesion molecule regulates the interaction between pancreatic cancer cells and stellate cells

    PubMed Central

    Zhang, Wei-Wei; Zhan, Shu-Hui; Geng, Chang-Xin; Sun, Xin; Erkan, Mert; Kleeff, Jörg; Xie, Xiang-Jun

    2016-01-01

    Activated leukocyte cell adhesion molecule (ALCAM/CD166) is a transmembrane glycoprotein that is involved in tumor progression and metastasis. In the present study, the expression and functional role of ALCAM in pancreatic cancer cells and pancreatic stellate cells (PSCs) was investigated. Tissue specimens were obtained from patients with pancreatic ductal adenocarcinoma (n=56) or chronic pancreatitis (CP; n=10), who underwent pancreatic resection, and from normal pancreatic tissue samples (n=10). Immunohistochemistry was used to analyze the localization and expression of ALCAM in pancreatic tissues. Subsequently, reverse transcription-quantitative polymerase chain reaction and immunoblotting were applied to assess the expression of ALCAM in pancreatic cancer Panc-1 and T3M4 cells, as well as in PSCs. An enzyme-linked immunosorbent assay was used to measure ALCAM levels in cell culture medium stimulated by hypoxia, tumor necrosis factor (TNF)-α and transforming growth factor-β. Silencing of ALCAM was performed using ALCAM small interfering (si)RNA and immunocytochemistry was used to analyze the inhibition efficiency. An invasion assay and a cell interaction assay were performed to assess the invasive ability and co-cultured adhesive potential of Panc-1 and T3M4 cells, as well as PSCs. Histologically, ALCAM expression was generally weak or absent in pancreatic cancer cells, but was markedly upregulated in PSCs in pancreatic cancer tissues. ALCAM was highly expressed in PSCs from CP tissues and PSCs surrounding pancreatic intraepithelial neoplasias, as well as in pancreatic cancer cells. ALCAM mRNA was highly expressed in PSCs, with a low to moderate expression in T3M4 and Panc-1 cells. Similar to the mRNA expression, immunoblotting demonstrated that ALCAM protein levels were high in PSCs and T3M4 cells, but low in Panc-1 cells. The expression of TNF-α increased, while hypoxia decreased the secretion of ALCAM in pancreatic cancer Panc-1 and T3M4 cells, and also in

  3. Proper migration and axon outgrowth of zebrafish cranial motoneuron subpopulations require the cell adhesion molecule MDGA2A

    PubMed Central

    Ingold, Esther; vom Berg-Maurer, Colette M.; Burckhardt, Christoph J.; Lehnherr, André; Rieder, Philip; Keller, Philip J.; Stelzer, Ernst H.; Greber, Urs F.; Neuhauss, Stephan C. F.; Gesemann, Matthias

    2015-01-01

    ABSTRACT The formation of functional neuronal circuits relies on accurate migration and proper axonal outgrowth of neuronal precursors. On the route to their targets migrating cells and growing axons depend on both, directional information from neurotropic cues and adhesive interactions mediated via extracellular matrix molecules or neighbouring cells. The inactivation of guidance cues or the interference with cell adhesion can cause severe defects in neuronal migration and axon guidance. In this study we have analyzed the function of the MAM domain containing glycosylphosphatidylinositol anchor 2A (MDGA2A) protein in zebrafish cranial motoneuron development. MDGA2A is prominently expressed in distinct clusters of cranial motoneurons, especially in the ones of the trigeminal and facial nerves. Analyses of MDGA2A knockdown embryos by light sheet and confocal microscopy revealed impaired migration and aberrant axonal outgrowth of these neurons; suggesting that adhesive interactions mediated by MDGA2A are required for the proper arrangement and outgrowth of cranial motoneuron subtypes. PMID:25572423

  4. Development and implementation of a miniaturized high-throughput time-resolved fluorescence energy transfer assay to identify small molecule inhibitors of polo-like kinase 1.

    PubMed

    Sharlow, Elizabeth R; Leimgruber, Stephanie; Shun, Tong Ying; Lazo, John S

    2007-12-01

    Polo-like kinase (Plk) 1 is a key enzyme involved in regulating the mammalian cell cycle that is also a validated anticancer drug target. Nonetheless, there are relatively few readily available potent and selective small molecule inhibitors of Plk1. To increase the availability of pharmacologically valuable Plk1 inhibitors, we describe herein the development, variability assessment, validation, and implementation of a 384-well automated, miniaturized high-throughput time-resolved fluorescence energy transfer screening assay designed to identify Plk1 kinase inhibitors. Using a small molecule library of pharmaceutically active compounds to gauge high-throughput assay robustness and reproducibility, we found nine general kinase inhibitors, including H-89, which was selected as the minimum control. We then interrogated a 97,101 compound library from the National Institutes of Health repository for small molecule inhibitors of Plk1 kinase activity. The initial primary hit rate in a single 10 microM concentration format was 0.21%. Hit compounds were subjected to concentration-response confirmation and interference assays. Identified in the screen were seven compounds with 50% inhibitory concentration (IC50) values below 1 microM, 20 compounds with IC50 values between 1 microM and 5 microM, and eight compounds with IC50 values between 5 and 10 microM, which could be assigned to seven distinct chemotype classes. Hit compounds were also examined for their ability to inhibit other kinases such as protein kinase D, focal adhesion kinase, rho-associated coiled coil protein kinase 2, c-jun NH2-terminal kinase 3, and protein kinase A via experimentation or data-mining. These compounds should be useful as probes for the biological activity of Plk1 and as leads for the development of new selective inhibitors of Plk1. PMID:18181689

  5. Modulation of endogenous Cysteine Protease Inhibitor (ICP) 1 expression in Entamoeba histolytica affects amoebic adhesion to Extracellular Matrix proteins.

    PubMed

    Lee, Young Ah; Saito-Nakano, Yumiko; Kim, Kyeong Ah; Min, Arim; Nozaki, Tomoyoshi; Shin, Myeong Heon

    2015-02-01

    Entamoeba histolytica is an enteric tissue-invading protozoan parasite that causes amoebic colitis and occasionally liver abscess in humans. During tissue invasion, amoebic adhesion to host components is an important event for host cell death leading to successful invasion and infection. Among amoebic virulence factors, Gal/GalNAc lectin is known to be major adhesion factor to host cells. In this study, we investigated the role of amoebic secreted CP (Cysteine Proteases) in amoebic adhesion to extracellular matrix (ECM) protein using CP inhibitor and E. histolytica strains in which the endogenous inhibitor of cysteine protease (ICP) 1 gene was overexpressed (ICP1(+)) or repressed by antisense small RNA-mediated gene silencing (ICP1(-)). We found that pretreatment of wild-type amoebae with CP inhibitor E64, or thiol-group modifiers such as diamide and N-Ethylmaleimide resulted in a significant decrease in adhesion to laminin and collagen ECM proteins. Furthermore, ICP1(+) strain, with a reduction of secreted CP activity, exhibited reduced ability by 40% to adhere to laminin. In contrast, ICP1(-) strain, with a 1.9-fold increase of secreted CP activity, showed a two-fold increase in amoebic adherence to laminin compared to the control strain. In addition, total amount of secreted CP5 was decreased in ICP1(+) amoeba. Conversely, total amount of secreted CP1 and mature-form CP5 were increased in ICP1(-) amoeba. We also found that ICP1 was secreted into extracellular milieu. These results suggest that secreted CP activity by E. histolytica may be an important factor affecting adhesion to host proteins, and regulation of CP secretion by ICP plays a major role in pathogenesis. This study provides insight into the CP-mediated tissue pathogenesis in amoeba-invaded lesions during human amoebiasis.

  6. Modulation of endogenous Cysteine Protease Inhibitor (ICP) 1 expression in Entamoeba histolytica affects amoebic adhesion to Extracellular Matrix proteins.

    PubMed

    Lee, Young Ah; Saito-Nakano, Yumiko; Kim, Kyeong Ah; Min, Arim; Nozaki, Tomoyoshi; Shin, Myeong Heon

    2015-02-01

    Entamoeba histolytica is an enteric tissue-invading protozoan parasite that causes amoebic colitis and occasionally liver abscess in humans. During tissue invasion, amoebic adhesion to host components is an important event for host cell death leading to successful invasion and infection. Among amoebic virulence factors, Gal/GalNAc lectin is known to be major adhesion factor to host cells. In this study, we investigated the role of amoebic secreted CP (Cysteine Proteases) in amoebic adhesion to extracellular matrix (ECM) protein using CP inhibitor and E. histolytica strains in which the endogenous inhibitor of cysteine protease (ICP) 1 gene was overexpressed (ICP1(+)) or repressed by antisense small RNA-mediated gene silencing (ICP1(-)). We found that pretreatment of wild-type amoebae with CP inhibitor E64, or thiol-group modifiers such as diamide and N-Ethylmaleimide resulted in a significant decrease in adhesion to laminin and collagen ECM proteins. Furthermore, ICP1(+) strain, with a reduction of secreted CP activity, exhibited reduced ability by 40% to adhere to laminin. In contrast, ICP1(-) strain, with a 1.9-fold increase of secreted CP activity, showed a two-fold increase in amoebic adherence to laminin compared to the control strain. In addition, total amount of secreted CP5 was decreased in ICP1(+) amoeba. Conversely, total amount of secreted CP1 and mature-form CP5 were increased in ICP1(-) amoeba. We also found that ICP1 was secreted into extracellular milieu. These results suggest that secreted CP activity by E. histolytica may be an important factor affecting adhesion to host proteins, and regulation of CP secretion by ICP plays a major role in pathogenesis. This study provides insight into the CP-mediated tissue pathogenesis in amoeba-invaded lesions during human amoebiasis. PMID:25500214

  7. Extracellular Matrix can Recover the Downregulation of Adhesion Molecules after Cell Detachment and Enhance Endothelial Cell Engraftment.

    PubMed

    He, Ningning; Xu, Yang; Du, Wei; Qi, Xin; Liang, Lu; Wang, Yuebing; Feng, Guowei; Fan, Yan; Han, Zhongchao; Kong, Deling; Cheng, Zhen; Wu, Joseph C; He, Zuoxiang; Li, Zongjin

    2015-01-01

    The low cell engraftment after transplantation limits the successful application of stem cell therapy and the exact pathway leading to acute donor cell death following transplantation is still unknown. Here we investigated if processes involved in cell preparation could initiate downregulation of adhesion-related survival signals, and further affect cell engraftment after transplantation. Human embryonic stem cell-derived endothelial cells (hESC-ECs) were suspended in PBS or Matrigel and kept at 4 °C. Quantitative RT-PCR analysis was used to test the adhesion and apoptosis genes' expression of hESC-ECs. We demonstrated that cell detachment can cause downregulation of cell adhesion and extracellular matrix (ECM) molecules, but no obvious cell anoikis, a form of apoptosis after cell detachment, was observed. The downregulation of adhesion and ECM molecules could be regained in the presence of Matrigel. Finally, we transplanted hESC-ECs into a mouse myocardial ischemia model. When transplanted with Matrigel, the long-term engraftment of hESC-ECs was increased through promoting angiogenesis and inhibiting apoptosis, and this was confirmed by bioluminescence imaging. In conclusion, ECM could rescue the functional genes expression after cell detached from culture dish, and this finding highlights the importance of increasing stem cell engraftment by mimicking stem cell niches through ECM application.

  8. Mice lacking the synaptic adhesion molecule Neph2/Kirrel3 display moderate hyperactivity and defective novel object preference

    PubMed Central

    Choi, Su-Yeon; Han, Kihoon; Cutforth, Tyler; Chung, Woosuk; Park, Haram; Lee, Dongsoo; Kim, Ryunhee; Kim, Myeong-Heui; Choi, Yeeun; Shen, Kang; Kim, Eunjoon

    2015-01-01

    Synaptic adhesion molecules regulate diverse aspects of neuronal synapse development, including synapse specificity, formation, and maturation. Neph2, also known as Kirrel3, is an immunoglobulin superfamily adhesion molecule implicated in intellectual disability, neurocognitive delay associated with Jacobsen syndrome, and autism spectrum disorders. We here report mice lacking Neph2 (Neph2-/- mice) display moderate hyperactivity in a familiar, but not novel, environment and defective novel object recognition with normal performances in Morris water maze spatial learning and memory, contextual fear conditioning and extinction, and pattern separation tests. These mice also show normal levels of anxiety-like behaviors, social interaction, and repetitive behaviors. At the synapse level, Neph2-/- dentate gyrus granule cells exhibit unaltered dendritic spine density and spontaneous excitatory synaptic transmission. These results suggest that Neph2 is important for normal locomotor activity and object recognition memory. PMID:26283919

  9. Nitric oxide pretreatment enhances atheroma component highlighting in vivo with intercellular adhesion molecule-1-targeted echogenic liposomes.

    PubMed

    Kee, Patrick H; Kim, Hyunggun; Huang, Shaoling; Laing, Susan T; Moody, Melanie R; Vela, Deborah; Klegerman, Melvin E; McPherson, David D

    2014-06-01

    We present an ultrasound technique for the detection of inflammatory changes in developing atheromas. We used contrast-enhanced ultrasound imaging with (i) microbubbles targeted to intercellular adhesion molecule-1 (ICAM-1), a molecule of adhesion involved in inflammatory processes in lesions of atheromas in New Zealand White rabbits, and (ii) pretreatment with nitric oxide-loaded microbubbles and ultrasound activation at the site of the endothelium to enhance the permeability of the arterial wall and the penetration of ICAM-1-targeted microbubbles. This procedure increases acoustic enhancement 1.2-fold. Pretreatment with nitric oxide-loaded echogenic liposomes and ultrasound activation can potentially facilitate the subsequent penetration of targeted echogenic liposomes into the arterial wall, thus allowing improved detection of inflammatory changes in developing atheromas.

  10. Computational Analysis and Predictive Cheminformatics Modeling of Small Molecule Inhibitors of Epigenetic Modifiers

    PubMed Central

    Scaria, Vinod

    2016-01-01

    Background The dynamic and differential regulation and expression of genes is majorly governed by the complex interactions of a subset of biomolecules in the cell operating at multiple levels starting from genome organisation to protein post-translational regulation. The regulatory layer contributed by the epigenetic layer has been one of the favourite areas of interest recently. This layer of regulation as we know today largely comprises of DNA modifications, histone modifications and noncoding RNA regulation and the interplay between each of these major components. Epigenetic regulation has been recently shown to be central to development of a number of disease processes. The availability of datasets of high-throughput screens for molecules for biological properties offer a new opportunity to develop computational methodologies which would enable in-silico screening of large molecular libraries. Methods In the present study, we have used data from high throughput screens for the inhibitors of epigenetic modifiers. Computational predictive models were constructed based on the molecular descriptors. Machine learning algorithms for supervised training, Naive Bayes and Random Forest, were used to generate predictive models for the small molecule inhibitors of histone methyl-transferases and demethylases. Random forest, with the accuracy of 80%, was identified as the most accurate classifier. Further we complemented the study with substructure search approach filtering out the probable pharmacophores from the active molecules leading to drug molecules. Results We show that effective use of appropriate computational algorithms could be used to learn molecular and structural correlates of biological activities of small molecules. The computational models developed could be potentially used to screen and identify potential new biological activities of molecules from large molecular libraries and prioritise them for in-depth biological assays. To the best of our knowledge

  11. Efficient Isothermal Titration Calorimetry Technique Identifies Direct Interaction of Small Molecule Inhibitors with the Target Protein.

    PubMed

    Gal, Maayan; Bloch, Itai; Shechter, Nelia; Romanenko, Olga; Shir, Ofer M

    2016-01-01

    Protein-protein interactions (PPI) play a critical role in regulating many cellular processes. Finding novel PPI inhibitors that interfere with specific binding of two proteins is considered a great challenge, mainly due to the complexity involved in characterizing multi-molecular systems and limited understanding of the physical principles governing PPIs. Here we show that the combination of virtual screening techniques, which are capable of filtering a large library of potential small molecule inhibitors, and a unique secondary screening by isothermal titration calorimetry, a label-free method capable of observing direct interactions, is an efficient tool for finding such an inhibitor. In this study we applied this strategy in a search for a small molecule capable of interfering with the interaction of the tumor-suppressor p53 and the E3-ligase MDM2. We virtually screened a library of 15 million small molecules that were filtered to a final set of 80 virtual hits. Our in vitro experimental assay, designed to validate the activity of mixtures of compounds by isothermal titration calorimetry, was used to identify an active molecule against MDM2. At the end of the process the small molecule (4S,7R)-4-(4-chlorophenyl)-5-hydroxy-2,7-dimethyl-N-(6-methylpyridin-2-yl)-4,6,7,8 tetrahydrIoquinoline-3-carboxamide was found to bind MDM2 with a dissociation constant of ~2 µM. Following the identification of this single bioactive compound, spectroscopic measurements were used to further characterize the interaction of the small molecule with the target protein. 2D NMR spectroscopy was used to map the binding region of the small molecule, and fluorescence polarization measurement confirmed that it indeed competes with p53.

  12. Histone deacetylase inhibitor givinostat: the small-molecule with promising activity against therapeutically challenging haematological malignancies.

    PubMed

    Ganai, Shabir Ahmad

    2016-08-01

    Histone acetyl transferases and histone deacetylases (HDACs) are counteracting epigenetic enzymes regulating the turnover of histone acetylation thereby regulating transcriptional events in a precise manner. Deregulation of histone acetylation caused by aberrant expression of HDACs plays a key role in tumour onset and progression making these enzymes as candidate targets for anticancer drugs and therapy. Small-molecules namely histone deacetylase inhibitors (HDACi) modulating the biological function of HDACs have shown multiple biological effects including differentiation, cell cycle arrest and apoptosis in tumour models. HDACi in general have been described in plethora of reviews with respect to various cancers. However, no review article is available describing thoroughly the role of inhibitor givinostat (ITF2357 or [6-(diethylaminomethyl) naphthalen-2-yl] methyl N-[4-(hydroxycarbamoyl) phenyl] carbamate) in haematological malignancies. Thus, the present review explores the intricate role of novel inhibitor givinostat in the defined malignancies including multiple myeloma, acute myelogenous leukaemia, Hodgkin's and non-Hodgkin's lymphoma apart from myeloproliferative neoplasms. The distinct molecular mechanisms triggered by this small-molecule inhibitor in these cancers to exert cytotoxic effect have also been dealt with. The article also highlights the combination strategy that can be used for enhancing the therapeutic efficiency of this inhibitor in the upcoming future. PMID:27121910

  13. Soluble adhesion molecules correlate with surface expression in an in vitro model of endothelial activation.

    PubMed

    Kjaergaard, Anders G; Dige, Anders; Krog, Jan; Tønnesen, Else; Wogensen, Lise

    2013-10-01

    Endothelial activation is a pivotal event in the development and progression of inflammation. Central to endothelial activation is the up-regulation of cellular adhesion molecules (CAMs) including E-selectin (CD62E), ICAM-1 (CD54), VCAM-1 (CD106) and PECAM-1 (CD31). These CAMs are also found in soluble forms (sCAMs). In this in vitro study of endothelial activation, we examined whether the levels of sCAMs correlate with the endothelial surface expression of CAMs in a dose-dependent and time-dependent manner. Such a correlation would support the use of sCAMs as surrogate markers for endothelial activation in inflammatory conditions. Human umbilical vein endothelial cells (HUVEC) were cultured with various concentrations of TNF-α for 8 hr and at a fixed concentration of TNF-α for various durations. The levels of soluble and surface-bound E-selectin, ICAM-1, VCAM-1 and PECAM-1 were quantified by flow cytometry. TNF-α stimulation increased CAM and sCAM expression in a dose-dependent and time-dependent manner. There was a significant positive correlation between the levels of ICAM-1 and sICAM-1 and between the levels of VCAM and sVCAM-1 in both the dose-response and time-response experiments. A positive correlation between the levels of E-selectin and sE-selectin was observed in the time-response experiment. This study supports the use of sCAMs as potential biomarkers of endothelial activation. In particular, the use of sICAM-1, sVCAM-1 and sE-selectin seems promising.

  14. Cell adhesion molecules as a marker reflecting the reduction of endothelial activation induced by glucocorticoids.

    PubMed

    Leone, Marc; Boutière-Albanèse, Brigitte; Valette, Sarah; Camoin-Jau, Laurence; Barrau, Karine; Albanèse, Jacques; Martin, Claude; Dignat-George, Françoise

    2004-04-01

    In vitro, steroids down-regulate the expression of cell adhesion molecules (CAMs) in endothelial cells stimulated by lipopolysaccharide. Low-dose hydrocortisone is a new treatment of patients with septic shock, a state that is characterized by an endothelial injury. The aim of the present study was to investigate whether the plasma levels of soluble CAMs, reflecting in vivo endothelial activation, could be modulated in patients with septic shock treated by hydrocortisone. This was a prospective and observational study conducted in the intensive care unit at a university hospital. The subjects included 40 patients with septic shock (American College of Chest Physicians Consensus Conference/Society of Critical Care Medicine definition); 45 healthy blood donors served as controls. The patients receiving the standard care ("reference group") during the first 6 months were compared with the patients receiving the hydrocortisone therapy ("hydrocortisone group") for the next 6 months. Measurements of sCAMs were performed on days 1 and 3 of the disease. On day 1, sE-selectin, sP-selectin, sVCAM-1, and sICAM-1 were significantly elevated in patients with septic shock compared with healthy donors. sE-selectin levels significantly decreased between days 1 and 3 in the "hydrocortisone group," whereas there was no significant change in the "reference group". Surprisingly, sICAM-1 levels significantly increased between days 1 and 3 only in patients treated by hydrocortisone. No significant changes were observed for sP-selectin and sVCAM-1 levels in the two groups. In patients with septic shock, glucocorticoids differently affected the pattern of evolution of sCAMs, with sE-selectin being decreased and sICAM-1 being increased. Expression of sP-selectin and sVCAM-1 was not affected.

  15. Perinodular ductular reaction/epithelial cell adhesion molecule loss in small hepatic nodules

    PubMed Central

    Zhang, Qin; Zhang, Chuan-Shan; Xin, Qi; Ma, Zhe; Liu, Gui-Qiu; Liu, Bing-Bing; Wang, Feng-Mei; Gao, Ying-Tang; Du, Zhi

    2014-01-01

    AIM: To investigate if loss of epithelial cell adhesion molecule (EpCAM) is associated with microinvasion in hepatocellular carcinomas (HCCs) in the presence of chronic hepatitis B. METHODS: The expression of EpCAM, cytokeratin 7 (CK7) and CK19 in 112 hepatic nodules was studied, including 20 HCCs with nodules ≤ 3 cm, 26 HCCs with nodules > 3 cm, 20 high-grade dysplastic nodules, 26 cirrhotic, large regenerative nodules and 20 cases of cirrhosis. RESULTS: Membranes of ductular reaction (DR) hepatobiliary cells, interlobular bile duct and some hepatic cells were positive for EpCAM expression. Active expression of DR/EpCAM was observed in the majority of noninvasive nodules (50/66, 75.76%); however, expression was absent in the major area of invasion in HCCs (42/46, 91.30%). DR/EpCAM loss in HCCs ≤ 3 cm was higher than in high-grade dysplastic nodules (HGDNs) (P < 0.05), cirrhotic, large regenerative nodules and cirrhosis (P < 0.01). Furthermore, patients (20 HCCs ≤ 3 cm, 26 HCCs > 3 cm, 20 HGDNs) with DR/EpCAM expression had a higher overall survival rate (P < 0.01) and lower early recurrence rate (P < 0.01). DR/EpCAM expression showed a close relationship with DR/CK7 and DR/CK19 expression (P < 0.01). The area under the receiver operating characteristic (ROC) curve of DR/EpCAM was similar to that of DR/CK7 and DR/CK19 (P > 0.05). The diagnostic specificity and diagnostic accuracy were both increased when DR/EpCAM, DR/CK7 and DR/CK19 were combined (P < 0.01). CONCLUSION: DR/EpCAM loss may be a useful marker for determining microinvasion in HCCs ≤ 3 cm, but also for predicting prognosis. PMID:25152593

  16. Neural Cell Adhesion Molecule NrCAM Regulates Semaphorin 3F-Induced Dendritic Spine Remodeling

    PubMed Central

    Demyanenko, Galina P.; Mohan, Vishwa; Zhang, Xuying; Brennaman, Leann H.; Dharbal, Katherine E.S.; Tran, Tracy S.; Manis, Paul B.

    2014-01-01

    Neuron-glial related cell adhesion molecule (NrCAM) is a regulator of axon growth and repellent guidance, and has been implicated in autism spectrum disorders. Here a novel postsynaptic role for NrCAM in Semaphorin3F (Sema3F)-induced dendritic spine remodeling was identified in pyramidal neurons of the primary visual cortex (V1). NrCAM localized to dendritic spines of star pyramidal cells in postnatal V1, where it was coexpressed with Sema3F. NrCAM deletion in mice resulted in elevated spine densities on apical dendrites of star pyramidal cells at both postnatal and adult stages, and electron microscopy revealed increased numbers of asymmetric synapses in layer 4 of V1. Whole-cell recordings in cortical slices from NrCAM-null mice revealed increased frequency of mEPSCs in star pyramidal neurons. Recombinant Sema3F-Fc protein induced spine retraction on apical dendrites of wild-type, but not NrCAM-null cortical neurons in culture, while re-expression of NrCAM rescued the spine retraction response. NrCAM formed a complex in brain with Sema3F receptor subunits Neuropilin-2 (Npn-2) and PlexinA3 (PlexA3) through an Npn-2-binding sequence (TARNER) in the extracellular Ig1 domain. A trans heterozygous genetic interaction test demonstrated that Sema3F and NrCAM pathways interacted in vivo to regulate spine density in star pyramidal neurons. These findings reveal NrCAM as a novel postnatal regulator of dendritic spine density in cortical pyramidal neurons, and an integral component of the Sema3F receptor complex. The results implicate NrCAM as a contributor to excitatory/inhibitory balance in neocortical circuits. PMID:25143608

  17. Differential up-regulation of circulating soluble and endothelial cell intercellular adhesion molecule-1 in mice.

    PubMed Central

    Komatsu, S.; Flores, S.; Gerritsen, M. E.; Anderson, D. C.; Granger, D. N.

    1997-01-01

    Although circulating levels of soluble intercellular adhesion molecule-1 (sICAM-1) are frequently used as an indicator of the severity of different immune, inflammatory, or neoplastic diseases, little is known about the factors that govern plasma sICAM-1 concentration and its relationship to the membranous form of ICAM-1 (mICAM-1) expressed on vascular endothelial cells. Plasma sICAM-1 concentration (measured by enzyme-linked immunosorbent assay) and mICAM-1 expression (measured using the dual radiolabeled monoclonal antibody technique) in different vascular beds (eg, lung, small intestine, and spleen) were monitored in wild-type (C57BL) and ICAM-1-deficient mice, before and after administration of tumor necrosis factor (TNF)-alpha. In wild-type mice, TNF-alpha elicited time-dependent increases in lung and intestine mICAM-1 (plateau achieved at 12 hours), with a corresponding increase in plasma sICAM-1 (peaked at 5 hours and then declined). The initial increases in mICAM-1 and pulmonary leukocyte sequestration (measured as lung myeloperoxidase activity) induced by TNF-alpha preceded any detectable elevation in sICAM-1. In ICAM-1-deficient mice, plasma sICAM-1 was reduced by approximately 70%, with > 95% reductions of mICAM-1 in lung and intestine, and > 75% reduction in splenic accumulation of anti-ICAM-1 antibody. Although TNF-alpha doubled plasma sICAM-1 in ICAM-1-deficient mice, mICAM-1 was unaffected in all tissues. Either splenectomy or pretreatment with cycloheximide resulted in an attenuated TNF-induced increase in sICAM-1, without affecting mICAM-1 expression. These findings indicate that plasma sICAM-1 concentration does not accurately reflect the level of ICAM-1 expression on endothelial cells in different vascular beds. PMID:9212746

  18. R-Ras Regulates Murine T Cell Migration and Intercellular Adhesion Molecule-1 Binding

    PubMed Central

    Yan, Xiaocai; Yan, Mingfei; Guo, Yihe; Singh, Gobind; Chen, Yuhong; Yu, Mei; Wang, Demin; Hillery, Cheryl A.; Chan, Andrew M.

    2015-01-01

    The trafficking of T-lymphocytes to peripheral draining lymph nodes is crucial for mounting an adaptive immune response. The role of chemokines in the activation of integrins via Ras-related small GTPases has been well established. R-Ras is a member of the Ras-subfamily of small guanosine-5’-triphosphate-binding proteins and its role in T cell trafficking has been investigated in R-Ras null mice (Rras−/−). An examination of the lymphoid organs of Rras−/− mice revealed a 40% reduction in the cellularity of the peripheral lymph nodes. Morphologically, the high endothelial venules of Rras−/− mice were more disorganized and less mature than those of wild-type mice. Furthermore, CD4+ and CD8+ T cells from Rras−/− mice had approximately 42% lower surface expression of L-selectin/CD62L. These aberrant peripheral lymph node phenotypes were associated with proliferative and trafficking defects in Rras−/− T cells. Furthermore, R-Ras could be activated by the chemokine, CCL21. Indeed, Rras−/− T cells had approximately 14.5% attenuation in binding to intercellular adhesion molecule 1 upon CCL21 stimulation. Finally, in a graft-versus host disease model, recipient mice that were transfused with Rras−/− T cells showed a significant reduction in disease severity when compared with mice transplanted with wild-type T cells. These findings implicate a role for R-Ras in T cell trafficking in the high endothelial venules during an effective immune response. PMID:26710069

  19. Carcinoembryonic Antigen Cell Adhesion Molecule 1 long isoform modulates malignancy of poorly differentiated colon cancer cells

    PubMed Central

    Arabzadeh, Azadeh; Dupaul-Chicoine, Jeremy; Breton, Valérie; Haftchenary, Sina; Yumeen, Sara; Turbide, Claire; Saleh, Maya; McGregor, Kevin; Greenwood, Celia M T; Akavia, Uri David; Blumberg, Richard S; Gunning, Patrick T; Beauchemin, Nicole

    2015-01-01

    Objective Nearly 20%–29% of patients with colorectal cancer (CRC) succumb to liver or lung metastasis and there is a dire need for novel targets to improve the survival of patients with metastasis. The long isoform of the Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1-L or CC1-L) is a key regulator of immune surveillance in primary CRC, but its role in metastasis remains largely unexplored. We have examined how CC1-L expression impacts on colon cancer liver metastasis. Design Murine MC38 transfected with CC1-L were evaluated in vitro for proliferation, migration and invasion, and for in vivo experimental liver metastasis. Using shRNA silencing or pharmacological inhibition, we delineated the role in liver metastasis of Chemokine (C-C motif) Ligand 2 (CCL2) and Signal Transducer and Activator of Transcription 3 (STAT3) downstream of CC1-L. We further assessed the clinical relevance of these findings in a cohort of patients with CRC. Results MC38-CC1-L-expressing cells exhibited significantly reduced in vivo liver metastasis and displayed decreased CCL2 chemokine secretion and reduced STAT3 activity. Down-modulation of CCL2 expression and pharmacological inhibition of STAT3 activity in MC38 cells led to reduced cell invasion capacity and decreased liver metastasis. The clinical relevance of our findings is illustrated by the fact that high CC1 expression in patients with CRC combined with some inflammation-regulated and STAT3-regulated genes correlate with improved 10-year survival. Conclusions CC1-L regulates inflammation and STAT3 signalling and contributes to the maintenance of a less-invasive CRC metastatic phenotype of poorly differentiated carcinomas. PMID:25666195

  20. Interleukin-1 receptor accessory protein organizes neuronal synaptogenesis as a cell adhesion molecule.

    PubMed

    Yoshida, Tomoyuki; Shiroshima, Tomoko; Lee, Sung-Jin; Yasumura, Misato; Uemura, Takeshi; Chen, Xigui; Iwakura, Yoichiro; Mishina, Masayoshi

    2012-02-22

    Interleukin-1 receptor accessory protein (IL-1RAcP) is the essential component of receptor complexes mediating immune responses to interleukin-1 family cytokines. IL-1RAcP in the brain exists in two isoforms, IL-1RAcP and IL-1RAcPb, differing only in the C-terminal region. Here, we found robust synaptogenic activities of IL-1RAcP in cultured cortical neurons. Knockdown of IL-1RAcP isoforms in cultured cortical neurons suppressed synapse formation as indicated by decreases of active zone protein Bassoon puncta and dendritic protrusions. IL-1RAcP recovered the accumulation of presynaptic Bassoon puncta, while IL-1RAcPb rescued both Bassoon puncta and dendritic protrusions. Consistently, the expression of IL-1RAcP in cortical neurons enhances the accumulation of Bassoon puncta and that of IL-1RAcPb stimulated both Bassoon puncta accumulation and spinogenesis. IL-1RAcP interacted with protein tyrosine phosphatase (PTP) δ through the extracellular domain. Mini-exon peptides in the Ig-like domains of PTPδ splice variants were critical for their efficient binding to IL-1RAcP. The synaptogenic activities of IL-1RAcP isoforms were diminished in cortical neurons from PTPδ knock-out mice. Correspondingly, PTPδ required IL-1RAcPb to induce postsynaptic differentiation. Thus, IL-1RAcPb bidirectionally regulated synapse formation of cortical neurons. Furthermore, the spine densities of cortical and hippocampal pyramidal neurons were reduced in IL-1RAcP knock-out mice lacking both isoforms. These results suggest that IL-1RAcP isoforms function as trans-synaptic cell adhesion molecules in the brain and organize synapse formation. Thus, IL-1RAcP represents an interesting molecular link between immune systems and synapse formation in the brain.

  1. Expression and Localization of Neural Cell Adhesion Molecule and Polysialic Acid during Chick Corneal Development

    PubMed Central

    Schwend, Tyler; Conrad, Gary W.

    2012-01-01

    Purpose. To assay for expression and localization of neural cell adhesion molecule (NCAM) and polysialic acid (polySia) in the chick cornea during embryonic and postnatal development. Methods. Real time quantitative PCR and Western blot analyses were used to determine NCAM expression and polysiaylation in embryonic, hatchling, and adult chick corneas. Immunofluorescence staining for NCAM and polySia was conducted on cryosections of embryonic and adult corneas, whole embryonic corneas, and trigeminal neurons. Results. NCAM and ST8SiaII mRNA transcripts peaked by embryonic day (E)9, remained steady between E10 and E14 and slowly decreased thereafter during embryonic development. Both gene transcripts showed > 190-fold decline in the adult chick cornea compared with E9. In contrast, ST8SiaIV expression gradually decreased 26.5-fold from E6 to E19, increased thereafter, and rose to the early embryonic level in the adult cornea. Western blot analysis revealed NCAM was polysialylated and its expression developmentally changed. Other polysiaylated proteins aside from NCAM were also detected by Western blot analysis. Five NCAM isoforms including NCAM-120, NCAM-180 and three soluble NCAM isoforms with low molecular weights (87–96 kDa) were present in chick corneas, with NCAM-120 being the predominate isoform. NCAM was localized to the epithelium, stroma, and stromal extracellular matrix (ECM) of the embryonic cornea. In stroma, NCAM expression shifted from anterior to posterior stroma during embryonic development and eventually became undetectable in 20-week-old adult cornea. Additionally, both NCAM and polySia were detected on embryonic corneal and pericorneal nerves. Conclusions. NCAM and polySia are expressed and developmentally regulated in chick corneas. Both membrane-associated and soluble NCAM isoforms are expressed in chick corneas. The distributions of NCAM and polySia in cornea and on corneal nerves suggest their potential functions in corneal innervation. PMID

  2. High expression of epithelial cellular adhesion molecule in peritoneal metastasis of gastric cancer.

    PubMed

    Imano, Motohiro; Itoh, Tatsuki; Satou, Takao; Yasuda, Atsushi; Nishiki, Kohei; Kato, Hiroaki; Shiraishi, Osamu; Peng, Ying-Feng; Shinkai, Masayuki; Tsubaki, Masahiro; Yasuda, Takushi; Imamoto, Haruhiko; Nishida, Shozo; Takeyama, Yoshifumi; Furkawa, Hiroshi; Okuno, Kiyokata; Shiozaki, Hitoshi

    2013-12-01

    Intraperitoneally administrated epithelial cellular adhesion molecule (EpCAM) monoclonal antibody is a therapeutic agent in patients with malignant effusion in several types of carcinoma. However, the role of EpCAM in peritoneal metastasis (PM) lesions and primary lesions of gastric cancer (GC) is still unclear. Therefore, in this study, we investigated EpCAM expression in GC patients with PM. We investigated the expression of EpCAM in 35PM lesions and 104 biopsy samples as primary lesions. Immunohistochemical staining was performed using the Ventana Benchmark XT (Roche Diagnostics) system. EpCAM expression was evaluated by calculating the total immunostaining score, which is the product of the proportion score and the intensity score. Overexpression was defined as a total score greater than 4. All PM specimens showed overexpression of EpCAM, and GC cells in both the surface layer and the deep layer of the PM showed a high expression of EpCAM. Meanwhile, in the biopsy sample, the expression of EpCAM ranged from none to strong. The EpCAM score results for PM specimens and biopsy samples were 11.0 ± 2.0 and 6.9 ± 3.9, respectively. The difference between the scores was statistically significant (P < 0.05). The intraperitoneally administrated EpCAM antibody might have a anti-cancer effect in PM lesions of GC. Additionally, it can be assumed that only GC cells which express a high level of EpCAM might metastasize to the peritoneum.

  3. Vascular endothelial platelet endothelial cell adhesion molecule 1 (PECAM-1) regulates advanced metastatic progression

    PubMed Central

    DeLisser, Horace; Liu, Yong; Desprez, Pierre-Yves; Thor, Ann; Briasouli, Paraskevei; Handumrongkul, Chakrapong; Wilfong, Jonathon; Yount, Garret; Nosrati, Mehdi; Fong, Sylvia; Shtivelman, Emma; Fehrenbach, Melane; Cao, Gaoyuan; Moore, Dan H.; Nayak, Shruti; Liggitt, Denny; Kashani-Sabet, Mohammed; Debs, Robert

    2010-01-01

    Most patients who die from cancer succumb to treatment-refractory advanced metastatic progression. Although the early stages of tumor metastasis result in the formation of clinically silent micrometastatic foci, its later stages primarily reflect the progressive, organ-destructive growth of already advanced metastases. Early-stage metastasis is regulated by multiple factors within tumor cells as well as by the tumor microenvironment (TME). In contrast, the molecular determinants that control advanced metastatic progression remain essentially uncharacterized, precluding the development of therapies targeted against it. Here we show that the TME, functioning in part through platelet endothelial cell adhesion molecule 1 (PECAM-1), drives advanced metastatic progression and is essential for progression through its preterminal end stage. PECAM-1–KO and chimeric mice revealed that its metastasis-promoting effects are mediated specifically through vascular endothelial cell (VEC) PECAM-1. Anti–PECAM-1 mAb therapy suppresses both end-stage metastatic progression and tumor-induced cachexia in tumor-bearing mice. It reduces proliferation, but not angiogenesis or apoptosis, within advanced tumor metastases. Because its antimetastatic effects are mediated by binding to VEC rather than to tumor cells, anti–PECAM-1 mAb appears to act independently of tumor type. A modified 3D coculture assay showed that anti–PECAM-1 mAb inhibits the proliferation of PECAM-1–negative tumor cells by altering the concentrations of secreted factors. Our studies indicate that a complex interplay between elements of the TME and advanced tumor metastases directs end-stage metastatic progression. They also suggest that some therapeutic interventions may target late-stage metastases specifically. mAb-based targeting of PECAM-1 represents a TME-targeted therapeutic approach that suppresses the end stages of metastatic progression, until now a refractory clinical entity. PMID:20926749

  4. Loss of cell adhesion molecule CHL1 improves homeostatic adaptation and survival in hypoxic stress.

    PubMed

    Huang, X; Sun, J; Rong, W; Zhao, T; Li, D H; Ding, X; Wu, L Y; Wu, K; Schachner, M; Xiao, Z C; Zhu, L L; Fan, M

    2013-01-01

    Close homologue of L1 (CHL1) is a transmembrane cell adhesion molecule that is critical for brain development and for the maintenance of neural circuits in adults. Recent studies revealed that CHL1 has diverse roles and is involved in the regulation of recovery after spinal cord injury. CHL1 expression was downregulated in the cerebral cortex, hypothalamus, and brain stem after the induction of acute hypoxia (AH). In the current study, we sought to address the role of CHL1 in regulating homeostasis responses to hypoxia using CHL1-knockout (CHL1(-/-)) mice. We found that, compared with wild-type littermates, CHL1(-/-) mice showed a dramatically lower mortality rate and an augmented ventilatory response after they were subjected to AH. Immunofluorescence staining revealed that CHL1 was expressed in the carotid body (CB), the key oxygen sensor in rodents, and CHL1 expression level in the CB as assayed by western blot was decreased after hypoxic exposure. The number of glomus cells and the expression of tyrosine hydroxylase (a marker for glomus cells) in the CB of CHL1(-/-) mice appeared to be increased compared with CHL1(+/+) mice. In addition, in the ex vivo CB preparation, hypoxia induced a significantly greater afferent nerve discharge in CHL1(-/-) mice compared with CHL1(+/+) mice. Furthermore, the arterial blood pressure and plasma catecholamine levels of CHL1(-/-) mice were also significantly higher than those of CHL1(+/+) mice. Our findings first demonstrate that CHL1 is a novel intrinsic factor that is involved in CB function and in the ventilatory response to AH. PMID:23949217

  5. Expression of intercellular adhesive molecule-1 in liver cancer tissues andliver cancer metastasis

    PubMed Central

    Sun, Jing-Jing; Zhou, Xin-Da; Zhou, Ge; Liu, Yin-Kun

    1998-01-01

    AIM: To study the relationship between intercellular adhesive molecule-1 (ICAM-1) and liver cancer metastasis and to search for factors to predict metastasis of liver cancer. METHODS: ICAM-1 expression in fresh tissues of normal liver and hepatocellular cancer (HCC) was examined by immunoperoxidase staining. The expression of ICAM-1 in human hepatoma, tumor surrounding tissues and normal livers were semiquantitatively analyzed by Dot immuno blot. Tissue ICAM-1 expression at mRNA level was detected by Northern blot. RESULTS: All 6 cases of normal liver samples were negative in anti-ICAM-1 immunohistochemical staining, 80.0% (36/45) of HCC presented various ICAM-1 expression. The number of positive cells was a little higher in large tumors, tumors with intact capsule and metastasis, but there was no significant difference. Two cases with cancer embolus also had high ICAM-1 expression. ICAM-1 concentration in HCC (13.43 ± 0.09) was higher than that in tumor surrounding tissues (5.89 ± 0.17, P < 0.01) and normal livers (4.27 ± 0.21, P < 0.01). It was also higher in metastasis group (20.24 ± 0.30) than in nonmetastasis group (10.23 ± 0.12, P < 0.05). Northern blot analysis revealed that ICAM-1 expression at mRNA level was also higher in HCC and cancer embolus than that in tumor surrounding tissues and normal livers. CONCLUSION: Tissue ICAM-1 could indicate the growth and metastasis of HCC, and may be an index that can predict liver cancer metastasis. PMID:11819275

  6. Tie2 Signaling Enhances Mast Cell Progenitor Adhesion to Vascular Cell Adhesion Molecule-1 (VCAM-1) through α4β1 Integrin

    PubMed Central

    Kanemaru, Kazumasa; Noguchi, Emiko; Tokunaga, Takahiro; Nagai, Kei; Hiroyama, Takashi; Nakamura, Yukio; Tahara-Hanaoka, Satoko; Shibuya, Akira

    2015-01-01

    Mast cell (MC) activation contributes considerably to immune responses, such as host protection and allergy. Cell surface immunoreceptors expressed on MCs play an important role in MC activation. Although various immunoreceptors on MCs have been identified, the regulatory mechanism of MC activation is not fully understood. To understand the regulatory mechanisms of MC activation, we used gene expression analyses of human and mouse MCs to identify a novel immunoreceptor expressed on MCs. We found that Tek, which encodes Tie2, was preferentially expressed in the MCs of both humans and mice. However, Tie2 was not detected on the cell surface of the mouse MCs of the peritoneal cavity, ear skin, or colon lamina propria. In contrast, it was expressed on mouse bone marrow–derived MCs and bone marrow MC progenitors (BM-MCps). Stimulation of Tie2 by its ligand angiopoietin-1 induced tyrosine phosphorylation of Tie2 in MEDMC-BRC6, a mouse embryonic stem cell-derived mast cell line, and enhanced MEDMC-BRC6 and mouse BM-MCp adhesion to vascular cell adhesion molecule-1 (VCAM-1) through α4β1 integrin. These results suggest that Tie2 signaling induces α4β1 integrin activation on BM-MCps for adhesion to VCAM-1. PMID:26659448

  7. Lung endothelial dipeptidyl peptidase IV is an adhesion molecule for lung-metastatic rat breast and prostate carcinoma cells

    PubMed Central

    1993-01-01

    Attachment of circulating tumor cells to endothelial cell adhesion molecules restricted to select vascular compartments is thought to be responsible for site-specific metastasis. Lung-metastatic rat R3230AC- MET breast and RPC-2 prostate carcinoma cells bound outside-out endothelial cell membrane vesicles, prepared by perfusion of the rat lung vasculature with a low-strength formaldehyde solution, in significantly higher numbers than their nonmetastatic counterparts R3230AC-LR and RPC-LR. In contrast, vesicles derived from the vasculature of a nonmetastasized organ (e.g., hind leg muscle) showed no binding preference for either of the four tumor cell lines. Lung- derived endothelial vesicles were used here to generate mAbs against lung endothelial cell adhesion molecules. The first group of mice were actively immunized against lung endothelial vesicles, whereas the second group was injected with syngeneic mouse antiserum against leg endothelial vesicles before active immunization with lung endothelial vesicles. 17 hybridoma supernatants obtained from the two fusions bound lung vesicles with at least a 10-fold higher affinity than leg vesicles. Seven (four obtained by a passive/active immunization protocol) stained rat capillary endothelia. One mAb, mAb 8.6A3, inhibited specific adhesion of lung-derived vesicles to lung-metastatic breast and prostate carcinoma cells. Purification of the antigen (endothelial cell adhesion molecule) from rat lung extracts revealed a protein with a 110-kD mol wt. NH2-terminal sequencing established identity with dipeptidyl peptidase IV which had been reported to serve as a fibronectin-binding protein. These results indicate that vesicles obtained from in situ perfused organs are a convenient immunogen for the production of antibodies to compartment-specific endothelial cell surface molecules, and reinforce the concept that endothelial cell surface components are selectively recognized by circulating cancer cells during metastasis

  8. [Pathogenetic and clinical significance of the adhesion molecule expression on T cells of the lung in sarcoid alveolitis].

    PubMed

    Gerli, R; Galandrini, R; Agea, E; Bini, P; Tognellini, R

    1990-01-01

    A double immunofluorescence analysis of CD4+ cell population from bronchoalveolar lavage (BAL) fluid samples of patients with active pulmonary sarcoidosis was carried out. The results showed that, unlike BAL and peripheral blood CD4+ cells of healthy subjects, almost all BAL CD4+ cells of the patients highly express, besides CDw29 antigen, LFA-1 and ICAM-1 adhesion molecules. The co-expression of these molecules on BAL CD4+ cells during high intensity sarcoid alveolitis could represent a marker of immunological memory. The relevant pathogenetic and clinical implications of this observation are discussed. PMID:2199744

  9. Exploring the interaction between human focal adhesion kinase and inhibitors: a molecular dynamic simulation and free energy calculations.

    PubMed

    Zhan, Jiu-Yu; Zhang, Ji-Long; Wang, Yan; Li, Ye; Zhang, Hong-Xing; Zheng, Qing-Chuan

    2016-11-01

    Focal adhesion kinase is an important target for the treatment of many kinds of cancers. Inhibitors of FAK are proposed to be the anticancer agents for multiple tumors. The interaction characteristic between FAK and its inhibitors is crucial to develop new inhibitors. In the present article, we used Molecular Dynamic (MD) simulation method to explore the characteristic of interaction between FAK and three inhibitors (PHM16, TAE226, and ligand3). The MD simulation results together with MM-GB/SA calculations show that the combinations are enthalpy-driven process. Cys502 and Asp564 are both essential residues due to the hydrogen bond interactions with inhibitors, which was in good agreement with experimental data. Glu500 can form a non-classical hydrogen bond with each inhibitor. Arg426 can form electrostatic interactions with PHM16 and ligand3, while weaker with TAE226. The electronic static potential was employed, and we found that the ortho-position methoxy of TAE226 has a weaker negative charge than the meta-position one in PHM16 or ligand3. Ile428, Val436, Ala452, Val484, Leu501, Glu505, Glu506, Leu553, Gly563 Leu567, Ser568 are all crucial residues in hydrophobic interactions. The key residues in this work will be available for further inhibitor design of FAK and also give assistance to further research of cancer.

  10. Effects of marine n-3 fatty acids on circulating levels of soluble adhesion molecules in patients with chronic heart failure.

    PubMed

    Eschen, O; Christensen, J H; LA Rovere, M T; Romano, P; Sala, P; Schmidt, E B

    2010-01-01

    Inflammatory markers as circulating soluble cellular adhesion molecules (sCAMs) and high sensitive C-reactive protein (hsCRP) are elevated in patients with chronic heart failure (CHF), and may constitute an increased risk of adverse outcome. Marine n-3 polyunsaturated fatty acids ( n-3 PUFA) may have anti-inflammatory effect and reduce levels of sCAMs (soluble intercellular adhesion molecule-1 (sICAM-1), vascular adhesion molecule-1 (sVCAM-1), P-selectin) and hsCRP. In a randomized, controlled trial, 138 patients with NYHA class II-III CHF were allocated to receive a daily supplement of 0.9 g of n-3 PUFA or olive oil for 24 weeks. After supplementation, no significant changes occurred in sCAMs or hsCRP after adjusting for possible confounders. However, a significant reduction was observed in sP-selectin in patients receiving n-3 PUFA, but this result was only of borderline significance in a between-group analysis. In conclusion, a daily supplement with 0.9 g of n-3 PUFA does not significantly affect plasma levels of sCAMs or hs-CRP in patients with CHF. n-3 PUFA may reduce sP-selectin, indicating a possible effect on platelet (and endothelial) activation. The results also indicate that the low dose of n-3 PUFA used in many intervention trials does not have deleterious effects on sCAMs or hsCRP.

  11. Effects of Antioxidant Supplementation on Insulin Sensitivity, Endothelial Adhesion Molecules and Oxidative Stress in Normal Weight and Overweight Young Adults

    PubMed Central

    Vincent, Heather K.; Bourguignon, Cheryl M.; Weltman, Arthur L.; Vincent, Kevin R.; Barrett, Eugene; Innes, Karen E.; Taylor, Ann G.

    2012-01-01

    Objective To determine whether short-term antioxidant supplementation affects insulin sensitivity, endothelial adhesion molecule levels, and oxidative stress in overweight young adults. Methods and Procedures A randomized, double-blind, controlled study tested the effects of antioxidants (AOX) on measures of insulin sensitivity (homeostasis model assessment, HOMA and QUICKI), endothelial adhesion molecules (sICAM-1, sVCAM-1, sE-selectin), adiponectin and oxidative stress (lipid hydroperoxides, PEROX) in overweight and normal weight individuals (N=48, 18-30 years). Participants received either AOX (vitamin E 800IU, vitamin C 500mg, β-carotene 10mg) or placebo (PLC) for 8 weeks. Results HOMA values were initially higher in the overweight subjects and were lowered with AOX by week 8 (15% reduction, p=0.02). Adiponectin increased in both AOX groups. sICAM-1 and sE-selectin decreased in overweight AOX treated groups by 6% and 13%, respectively (p<0.05). Plasma PEROX were reduced by 0.31 and 0.70 nmol/ml in the normal weight and overweight AOX treated groups, respectively, by week 8 (p<0.05). Discussion AOX supplementation moderately lowers HOMA and endothelial adhesion molecule levels in overweight young adults. A potential mechanism to explain this finding is the reduction in oxidative stress by AOX. Long term studies are needed to determine whether AOX are effective in suppressing diabetes or vascular activation over time. PMID:19154960

  12. Drosophila chaoptin, a member of the leucine-rich repeat family, is a photoreceptor cell-specific adhesion molecule.

    PubMed Central

    Krantz, D E; Zipursky, S L

    1990-01-01

    Drosophila chaoptin, required for photoreceptor cell morphogenesis, is a member of the leucine-rich repeat family of proteins. On the basis of biochemical and genetic analyses we previously proposed that chaoptin might function as a cell adhesion molecule. To test this hypothesis, chaoptin cDNA driven by the hsp 70 promoter was transfected into non-self-adherent Drosophila Schneider line 2 (S2) cells. Following heat shock induction of chaoptin expression, the transfected S2 cells formed multicellular aggregates. Mixing experiments of chaoptin expressing and non-expressing cells suggest that chaoptin expressing cells adhere homotypically. Previously it was shown that chaoptin is exclusively localized to photoreceptor cells. Thus, chaoptin is a cell-type-specific adhesion molecule. Biochemical analyses presented in this paper demonstrate that chaoptin is linked to the extracellular surface of the plasma membrane by covalent attachment to glycosyl-phosphatidylinositol. We propose that chaoptin and several other members of the leucine-rich repeat family of proteins define a new class of cell adhesion molecules. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 8. PMID:2189727

  13. Effect of arginine on cellular adhesion molecule expression and leukocyte transmigration in endothelial cells stimulated by biological fluid from surgical patients.

    PubMed

    Yeh, Chiu-Li; Hsu, Chun-Sen; Chen, Soul-Chin; Hou, Yu-Chen; Chiu, Wan-Chun; Yeh, Sung-Ling

    2007-07-01

    This study investigated the effect of different arginine (Arg) concentrations on adhesion molecule expression on endothelial cells (ECs) and leukocytes and the transendothelial migration of polymorphonuclear neutrophils (PMNs) through ECs stimulated by plasma or peritoneal drain fluid (PDF) from surgical patients. Human umbilical vein ECs (HUVECs) and PMNs from healthy subjects were treated with different concentrations (0, 50, 100, and 1000 micromol/L) of Arg for 24 h. After that, HUVECs were stimulated for 3 h with plasma or PDF from patients who underwent abdominal surgery, and PMNs were allowed to transmigrate through ECs for 2 h. The HUVEC expression of cellular adhesion molecules (CAMs) and integrin (CD11b) and the interleukin (IL) 8 receptor expression on PMNs were measured by flow cytometry. The PMNs transmigrating through ECs were also analyzed. The results showed that CAM and integrin expressions in PDF groups were higher than those in control groups. Among the PDF groups, IL-8 secretions from ECs and PMNs were lower with 100 and 1000 micromol/L Arg than with 0 and 50 micromol/L Arg, and this was consistent with the expression of the IL-8 receptor on PMNs. In addition, CAM expressions on ECs and CD11b expression on PMNs, as well as PMN transmigration, were lower with 100 and 1000 micromol/L Arg than with 0 and 50 micromol/L Arg. The HUVECs stimulated by plasma from surgical patients had similar effects on surface molecule expression as PDF; however, as shown in PDF stimulation, the effects were not so obvious. Inhibition of nitric oxide production results in high CAM and IL-8 expressions comparable with groups with low Arg administration. The results of this in vitro study suggest that ECs and PMNs were activated after patients' plasma or PDF stimulation. A low Arg concentration comparable with catabolic conditions resulted in higher adhesion molecule expression and greater transendothelial migration of neutrophils. Arginine administration at levels

  14. Accelerated exchange of a buried water molecule in selectively disulfide-reduced bovine pancreatic trypsin inhibitor.

    PubMed

    Denisov, Vladimir P; Peters, Jörg; Hörlein, Hans Dietrich; Halle, Bertil

    2004-09-28

    Using magnetic relaxation dispersion (MRD), we have previously shown that the four internal water molecules in bovine pancreatic trypsin inhibitor (BPTI) exchange with bulk water on time scales between 10(-8) and 10(-4) s at room temperature. Because this exchange is controlled by the protein structure, internal water molecules can be used to probe rare conformational fluctuations. Here, we report (2)H and (17)O MRD data at three temperatures for wild-type BPTI and two BPTI variants where the 14-38 disulfide bond has been cleaved by a double Cys --> Ser mutation or by disulfide reduction and carboxamidomethylation. The MRD data show that the internal water molecules are conserved on disulfide cleavage. However, the exchange rate of the water molecule buried near the disulfide bond is enhanced by 2-4 orders of magnitude. The relation of water exchange to other dynamic processes in BPTI is discussed.

  15. Heterotypic binding between neuronal membrane vesicles and glial cells is mediated by a specific cell adhesion molecule

    PubMed Central

    1984-01-01

    By means of a multistage quantitative assay, we have identified a new kind of cell adhesion molecule (CAM) on neuronal cells of the chick embryo that is involved in their adhesion to glial cells. The assay used to identify the binding component (which we name neuron-glia CAM or Ng-CAM) was designed to distinguish between homotypic binding (e.g., neuron to neuron) and heterotypic binding (e.g., neuron to glia). This distinction was essential because a single neuron might simultaneously carry different CAMs separately mediating each of these interactions. The adhesion of neuronal cells to glial cells in vitro was previously found to be inhibited by Fab' fragments prepared from antisera against neuronal membranes but not by Fab' fragments against N-CAM, the neural cell adhesion molecule. This suggested that neuron-glia adhesion is mediated by specific cell surface molecules different from previously isolated CAMs . To verify that this was the case, neuronal membrane vesicles were labeled internally with 6-carboxyfluorescein and externally with 125I-labeled antibodies to N-CAM to block their homotypic binding. Labeled vesicles bound to glial cells but not to fibroblasts during a 30-min incubation period. The specific binding of the neuronal vesicles to glial cells was measured by fluorescence microscopy and gamma spectroscopy of the 125I label. Binding increased with increasing concentrations of both glial cells and neuronal vesicles. Fab' fragments prepared from anti-neuronal membrane sera that inhibited binding between neurons and glial cells were also found to inhibit neuronal vesicle binding to glial cells. The inhibitory activity of the Fab' fragments was depleted by preincubation with neuronal cells but not with glial cells. Trypsin treatment of neuronal membrane vesicles released material that neutralized Fab' fragment inhibition; after chromatography, neutralizing activity was enriched 50- fold. This fraction was injected into mice to produce monoclonal

  16. p53 Small Molecule Inhibitor Enhances Temozolomide Cytotoxic Activity against Intracranial Glioblastoma Xenografts

    PubMed Central

    Dinca, Eduard B.; Lu, Kan V.; Sarkaria, Jann N.; Pieper, Russell O.; Prados, Michael D.; Haas-Kogan, Daphne A.; VandenBerg, Scott R.; Berger, Mitchel S.; James, C. David

    2010-01-01

    In this study we investigated corresponding precursor and active forms of a p53 small molecule inhibitor for effect on temozolomide (TMZ) anti-tumor activity against glioblastoma (GBM), using both in vitro and in vivo experimental approaches. Results from in vitro cell viability analysis showed that the cytotoxic activity of TMZ was substantially increased when GBMs with wild-type p53 were co-treated with the active form of p53 inhibitor, and this heightened cytotoxic response was accompanied by increased PARP cleavage as well as elevated cellular phospho-H2AX. Analysis of the same series of GBMs, as intracranial xenografts in athymic mice, and administering corresponding p53 inhibitor precursor, that is converted to the active compound in vivo, yielded results consistent with the in vitro analyses: i.e., TMZ + p53 inhibitor precursor co-treatment, of three distinct wild-type p53 GBM xenografts, resulted in significant enhancement of TMZ anti-tumor effect relative to treatment with TMZ alone, as indicated by serial bioluminescence monitoring as well as survival analysis (p < 0.001 for co-treatment survival benefit in each case). Mice receiving intracranial injection with p53 null GBM showed similar survival benefit from TMZ treatment regardless of the presence or absence of p53 inhibitor precursor. In total, our results indicate that the p53 active and precursor inhibitor pair enhance TMZ cytotoxicity in vitro and in vivo, respectively, and do so in a p53-dependent manner. PMID:19074867

  17. p53 Small-molecule inhibitor enhances temozolomide cytotoxic activity against intracranial glioblastoma xenografts.

    PubMed

    Dinca, Eduard B; Lu, Kan V; Sarkaria, Jann N; Pieper, Russell O; Prados, Michael D; Haas-Kogan, Daphne A; Vandenberg, Scott R; Berger, Mitchel S; James, C David

    2008-12-15

    In this study, we investigated the precursor and active forms of a p53 small-molecule inhibitor for their effects on temozolomide (TMZ) antitumor activity against glioblastoma (GBM), using both in vitro and in vivo experimental approaches. Results from in vitro cell viability analysis showed that the cytotoxic activity of TMZ was substantially increased when p53 wild-type (p53(wt)) GBMs were cotreated with the active form of p53 inhibitor, and this heightened cytotoxic response was accompanied by increased poly(ADP-ribose) polymerase cleavage as well as elevated cellular phospho-H2AX. Analysis of the same series of GBMs, as intracranial xenografts in athymic mice, and administering corresponding p53 inhibitor precursor, which is converted to the active compound in vivo, yielded results consistent with the in vitro analyses: TMZ + p53 inhibitor precursor cotreatment of three distinct p53(wt) GBM xenografts resulted in significant enhancement of TMZ antitumor effect relative to treatment with TMZ alone, as indicated by serial bioluminescence monitoring as well as survival analysis (P < 0.001 for cotreatment survival benefit in each case). Mice receiving intracranial injection with p53(null) GBM showed similar survival benefit from TMZ treatment regardless of the presence or absence of p53 inhibitor precursor. In total, our results indicate that the p53 active and precursor inhibitor pair enhances TMZ cytotoxicity in vitro and in vivo, respectively, and do so in a p53-dependent manner.

  18. Antitumor activity of a small-molecule inhibitor of the histone kinase Haspin

    PubMed Central

    Huertas, D; Soler, M; Moreto, J; Villanueva, A; Martinez, A; Vidal, A; Charlton, M; Moffat, D; Patel, S; McDermott, J; Owen, J; Brotherton, D; Krige, D; Cuthill, S; Esteller, M

    2012-01-01

    The approval of histone deacetylase inhibitors for treatment of lymphoma subtypes has positioned histone modifications as potential targets for the development of new classes of anticancer drugs. Histones also undergo phosphorylation events, and Haspin is a protein kinase the only known target of which is phosphorylation of histone H3 at Thr3 residue (H3T3ph), which is necessary for mitosis progression. Mitotic kinases can be blocked by small drugs and several clinical trials are underway with these agents. As occurs with Aurora kinase inhibitors, Haspin might be an optimal candidate for the pharmacological development of these compounds. A high-throughput screening for Haspin inhibitors identified the CHR-6494 compound as being one promising such agent. We demonstrate that CHR-6494 reduces H3T3ph levels in a dose-dependent manner and causes a mitotic catastrophe characterized by metaphase misalignment, spindle abnormalities and centrosome amplification. From the cellular standpoint, the identified small-molecule Haspin inhibitor causes arrest in G2/M and subsequently apoptosis. Importantly, ex vivo assays also demonstrate its anti-angiogenetic features; in vivo, it shows antitumor potential in xenografted nude mice without any observed toxicity. Thus, CHR-6494 is a first-in-class Haspin inhibitor with a wide spectrum of anticancer effects that merits further preclinical research as a new member of the family of mitotic kinase inhibitors. PMID:21804608

  19. Differential modulation of IL-1-induced endothelial adhesion molecules and transendothelial migration of granulocytes by G-CSF.

    PubMed

    Eissner, G; Lindner, H; Reisbach, G; Klauke, I; Holler, E

    1997-06-01

    Granulocyte colony stimulating factor (G-CSF) is widely used for mobilization of haemopoietic stem cells into the peripheral blood. However, little is known about the mechanisms involved in mobilization and the immune modulatory effects of this growth factor. In this report we show that G-CSF down-regulated intercellular adhesion molecule 1 (ICAM-1) induced by Interleukin-1 (IL-1) on human endothelial cells. Interestingly, the G-CSF-mediated down-modulation of IL-1-induced ICAM-1 appeared to be biphasic. In pharmacological concentrations (> 300 ng/ml), and in dose ranges of plasma G-CSF levels above that of nonfebrile healthy individuals (30 pg/ml), a significant decrease in surface ICAM-1 could be observed. This could be explained, at least in part, by an increased autocrine G-CSF production by endothelial cells in response to IL-1 and exogenous G-CSF. In contrast to ICAM-1, IL-1-triggered VCAM-1 expression was superinduced by G-CSF with the optimal concentration of 30 pg/ml. To evaluate the functional significance of these findings, 51Cr adhesion assays with peripheral blood mononuclear cells (PBMC) or granulocytes known to lack the VCAM-1 counter-receptor very late antigen 4 (VLA-4) and IL-1-stimulated endothelial cells, in the presence or absence of G-CSF, were performed. G-CSF could not inhibit the IL-1-induced adhesion of PBMC to endothelial cells, which may be due to the differential adhesion molecule modulation. In contrast, granulocyte adhesion induced by IL-1 could effectively be blocked by co-incubation with G-CSF. Finally, G-CSF also inhibited transendothelial migration of granulocytes through IL-1-activated endothelial cells in a concentration-dependent manner.

  20. Different cytokeratin and neuronal cell adhesion molecule staining patterns in focal nodular hyperplasia and hepatic adenoma and their significance

    PubMed Central

    Iyer, Anita; Robert, Marie E.; Bifulco, Carlo B.; Salem, Ronald R.; Jain, Dhanpat

    2013-01-01

    Summary Differentiating focal nodular hyperplasia from hepatic adenoma can be challenging. Cytokeratin 7, neuronal cell adhesion molecule, and cytokeratin 19 are differentially expressed in hepatocytes, biliary epithelium, and possibly hepatic progenitor/stem cells. CD34 is known to have altered expression patterns in the hepatic endothelium in conditions associated with abnormal perfusion and in hepatocellular carcinoma. The purpose of this study was to examine the expression pattern of these markers in focal nodular hyperplasia and hepatic adenoma and assess their diagnostic use. Ten resection specimens each of hepatic adenoma and focal nodular hyperplasia (including a case of telangiectatic focal nodular hyperplasia) were selected for the study. Immunohistochemical analysis was performed using antibodies against cytokeratin 7, cytokeratin 19, neuronal cell adhesion molecule, and CD34 on formalin-fixed, paraffin-embedded sections from each case. The staining patterns and intensity for each marker were analyzed. In hepatic adenoma, the cytokeratin 7 stain revealed strong positivity in hepatocytes in patches, with a gradual decrease in the staining intensity as the cells differentiated towards mature hepatocytes. Although bile ducts were typically absent in hepatic adenoma, occasional ductules could be identified with cytokeratin 7 stain. In focal nodular hyperplasia, cytokeratin 7 showed strong staining of the biliary epithelium within the fibrous septa and staining of the peripheral hepatocytes of most lobules that was focal and weaker than hepatic adenoma. Cytokeratin 19 and neuronal cell adhesion molecule showed patchy and moderate staining in the biliary epithelium of the ductules in focal nodular hyperplasia. While in the hepatic adenoma, cytokeratin 19 showed only rare positivity in occasional cells within ductules, and neuronal cell adhesion molecule marked occasional isolated cells in the lesion. CD34 showed staining of sinusoids in the inflow areas

  1. Binding to large enzyme pockets: small-molecule inhibitors of trypanothione reductase.

    PubMed

    Persch, Elke; Bryson, Steve; Todoroff, Nickolay K; Eberle, Christian; Thelemann, Jonas; Dirdjaja, Natalie; Kaiser, Marcel; Weber, Maria; Derbani, Hassan; Brun, Reto; Schneider, Gisbert; Pai, Emil F; Krauth-Siegel, R Luise; Diederich, François

    2014-08-01

    The causative agents of the parasitic disease human African trypanosomiasis belong to the family of trypanosomatids. These parasitic protozoa exhibit a unique thiol redox metabolism that is based on the flavoenzyme trypanothione reductase (TR). TR was identified as a potential drug target and features a large active site that allows a multitude of possible ligand orientations, which renders rational structure-based inhibitor design highly challenging. Herein we describe the synthesis, binding properties, and kinetic analysis of a new series of small-molecule inhibitors of TR. The conjunction of biological activities, mutation studies, and virtual ligand docking simulations led to the prediction of a binding mode that was confirmed by crystal structure analysis. The crystal structures revealed that the ligands bind to the hydrophobic wall of the so-called "mepacrine binding site". The binding conformation and potency of the inhibitors varied for TR from Trypanosoma brucei and T. cruzi.

  2. The development and use of small molecule inhibitors of glycosphingolipid metabolism for lysosomal storage diseases

    PubMed Central

    Shayman, James A.; Larsen, Scott D.

    2014-01-01

    Glycosphingolipid (GSL) storage diseases have been the focus of efforts to develop small molecule therapeutics from design, experimental proof of concept studies, and clinical trials. Two primary alternative strategies that have been pursued include pharmacological chaperones and GSL synthase inhibitors. There are theoretical advantages and disadvantages to each of these approaches. Pharmacological chaperones are specific for an individual glycoside hydrolase and for the specific mutation present, but no candidate chaperone has been demonstrated to be effective for all mutations leading to a given disorder. Synthase inhibitors target single enzymes such as glucosylceramide synthase and inhibit the formation of multiple GSLs. A glycolipid synthase inhibitor could potentially be used to treat multiple diseases, but at the risk of lowering nontargeted cellular GSLs that are important for normal health. The basis for these strategies and specific examples of compounds that have led to clinical trials is the focus of this review. PMID:24534703

  3. Identification of small-molecule inhibitors of autotaxin that inhibit melanoma cell migration and invasion.

    PubMed

    Saunders, Lauren P; Ouellette, Amy; Bandle, Russ; Chang, William Chozen; Zhou, Hongwen; Misra, Raj N; De La Cruz, Enrique M; Braddock, Demetrios T

    2008-10-01

    Autotaxin (ATX) is a prometastatic enzyme initially isolated from the conditioned medium of human melanoma cells that stimulates a myriad of biological activities, including angiogenesis and the promotion of cell growth, survival, and differentiation through the production of lysophosphatidic acid (LPA). ATX increases the aggressiveness and invasiveness of transformed cells, and ATX levels directly correlate with tumor stage and grade in several human malignancies. To study the role of ATX in the pathogenesis of malignant melanoma, we developed antibodies and small-molecule inhibitors against recombinant human protein. Immunohistochemistry of paraffin-embedded human tissue shows that ATX levels are markedly increased in human primary and metastatic melanoma relative to benign nevi. Chemical screens identified several small-molecule inhibitors with binding constants ranging from nanomolar to low micromolar. Cell migration and invasion assays with melanoma cell lines show that ATX markedly stimulates melanoma cell migration and invasion, an effect suppressed by ATX inhibitors. The migratory phenotype can be rescued by the addition of the enzymatic product of ATX, LPA, confirming that the observed inhibition is linked to suppression of LPA production by ATX. Chemical analogues of the inhibitors show structure-activity relationships important for ATX inhibition and indicate pathways for their optimization. These studies suggest that ATX is an approachable molecular target for the rational design of chemotherapeutic agents directed against malignant melanoma.

  4. Rational design of small molecule inhibitors targeting the Ras GEF, SOS1

    PubMed Central

    Evelyn, Chris R.; Duan, Xin; Biesiada, Jacek; Seibel, William L.; Meller, Jaroslaw; Zheng, Yi

    2014-01-01

    Summary Ras GTPases regulate intracellular signaling involved in cell proliferation. Elevated Ras signaling activity has been associated with human cancers. Ras activation is catalyzed by guanine-nucleotide exchange factors (GEFs), of which SOS1 is a major member that transduces receptor tyrosine kinase signaling to Ras. We have developed a rational approach coupling virtual screening with experimental screening in identifying small-molecule inhibitors targeting the catalytic site of SOS1 and SOS1-regulated Ras activity. A lead inhibitor, NSC-658497, is found to bind to SOS1, competitively suppresses SOS1-Ras interaction, and dose-dependently inhibits SOS1 GEF activity. Mutagenesis and structure-activity relationship studies map the NSC-658497 site of action to the SOS1 catalytic site, and define the chemical moieties in the inhibitor essential for the activity. NSC-658497 showed dose-dependent efficacy in inhibiting Ras, downstream signaling activities, and associated cell proliferation. These studies establish a proof of principle for rational design of small-molecule inhibitors targeting Ras GEF enzymatic activity. PMID:25455859

  5. Rational design of small molecule inhibitors targeting the Ras GEF, SOS1.

    PubMed

    Evelyn, Chris R; Duan, Xin; Biesiada, Jacek; Seibel, William L; Meller, Jaroslaw; Zheng, Yi

    2014-12-18

    Ras GTPases regulate intracellular signaling involved in cell proliferation. Elevated Ras signaling activity has been associated with human cancers. Ras activation is catalyzed by guanine nucleotide exchange factors (GEFs), of which SOS1 is a major member that transduces receptor tyrosine kinase signaling to Ras. We have developed a rational approach coupling virtual screening with experimental screening in identifying small-molecule inhibitors targeting the catalytic site of SOS1 and SOS1-regulated Ras activity. A lead inhibitor, NSC-658497, was found to bind to SOS1, competitively suppress SOS1-Ras interaction, and dose-dependently inhibit SOS1 GEF activity. Mutagenesis and structure-activity relationship studies map the NSC-658497 site of action to the SOS1 catalytic site, and define the chemical moieties in the inhibitor essential for the activity. NSC-658497 showed dose-dependent efficacy in inhibiting Ras, downstream signaling activities, and associated cell proliferation. These studies establish a proof of principle for rational design of small-molecule inhibitors targeting Ras GEF enzymatic activity.

  6. Identification of a small molecule inhibitor of 3-phosphoglycerate dehydrogenase to target serine biosynthesis in cancers

    PubMed Central

    Mullarky, Edouard; Lucki, Natasha C.; Beheshti Zavareh, Reza; Anglin, Justin L.; Gomes, Ana P.; Nicolay, Brandon N.; Wong, Jenny C. Y.; Christen, Stefan; Takahashi, Hidenori; Singh, Pradeep K.; Blenis, John; Fendt, Sarah-Maria; Asara, John M.; DeNicola, Gina M.; Lyssiotis, Costas A.; Lairson, Luke L.; Cantley, Lewis C.

    2016-01-01

    Cancer cells reprogram their metabolism to promote growth and proliferation. The genetic evidence pointing to the importance of the amino acid serine in tumorigenesis is striking. The gene encoding the enzyme 3-phosphoglycerate dehydrogenase (PHGDH), which catalyzes the first committed step of serine biosynthesis, is overexpressed in tumors and cancer cell lines via focal amplification and nuclear factor erythroid-2-related factor 2 (NRF2)-mediated up-regulation. PHGDH-overexpressing cells are exquisitely sensitive to genetic ablation of the pathway. Here, we report the discovery of a selective small molecule inhibitor of PHGDH, CBR-5884, identified by screening a library of 800,000 drug-like compounds. CBR-5884 inhibited de novo serine synthesis in cancer cells and was selectively toxic to cancer cell lines with high serine biosynthetic activity. Biochemical characterization of the inhibitor revealed that it was a noncompetitive inhibitor that showed a time-dependent onset of inhibition and disrupted the oligomerization state of PHGDH. The identification of a small molecule inhibitor of PHGDH not only enables thorough preclinical evaluation of PHGDH as a target in cancers, but also provides a tool with which to study serine metabolism. PMID:26831078

  7. A Small-Molecule Screening Platform for the Discovery of Inhibitors of Undecaprenyl Diphosphate Synthase.

    PubMed

    Czarny, Tomasz L; Brown, Eric D

    2016-07-01

    The bacterial cell wall has long been a celebrated target for antibacterial drug discovery due to its critical nature in bacteria and absence in mammalian systems. At the heart of the cell wall biosynthetic pathway lies undecaprenyl phosphate (Und-P), the lipid-linked carrier upon which the bacterial cell wall is built. This study exploits recent insights into the link between late-stage wall teichoic acid inhibition and Und-P production, in Gram-positive organisms, to develop a cell-based small-molecule screening platform that enriches for inhibitors of undecaprenyl diphosphate synthase (UppS). Screening a chemical collection of 142,000 small molecules resulted in the identification of 6 new inhibitors of UppS. To date, inhibitors of UppS have generally shown off-target effects on membrane potential due to their physical-chemical characteristics. We demonstrate that MAC-0547630, one of the six inhibitors identified, exhibits selective, nanomolar inhibition against UppS without off-target effects on membrane potential. Such characteristics make it a unique chemical probe for exploring the inhibition of UppS in bacterial cell systems. PMID:27626101

  8. Secreted adhesion molecules of Strongyloides venezuelensis are produced by oesophageal glands and are components of the wall of tunnels constructed by adult worms in the host intestinal mucosa.

    PubMed

    Maruyama, H; El-Malky, M; Kumagai, T; Ohta, N

    2003-02-01

    The parasitic female of Strongyloides venezuelensis keeps invading the epithelial layer of the host intestinal mucosa. Upon invasion, it adheres to the surface of the intestinal epithelial cells with adhesion molecules secreted from the mouth. It has been demonstrated that S. venezuelensis are expelled from the intestine because mucosal mast cells inhibit the attachment of adult worms to the mucosal surface. In the present study, we generated specific antibodies against secreted adhesion molecules to investigate their function in vivo, because these molecules have been demonstrated only in vitro in spite of the importance in the infection processes. A mouse monoclonal antibody specific to S. venezuelensis adhesion molecules inhibited the attachment of adult worms to plastic dishes and the binding of adhesion molecules to rat intestinal epithelial cells. Immunohistochemical study revealed that adhesion molecules were produced by oesophageal glands and were continuously secreted in vivo to line the wall of the tunnels formed by adult worms in the intestinal mucosa. Our findings indicate that adhesion molecules play essential roles in the infection processes of S. venezuelensis in the host intestine. PMID:12636354

  9. Expression of intercellular adhesion molecule-1 on macrophages in vitro as a marker of activation.

    PubMed

    Bernatchez, S F; Atkinson, M R; Parks, P J

    1997-10-01

    Macrophage activation is a major component of wound healing. It also determines the extent of inflammatory reactions and the response of the body to implanted materials. We have previously shown, using an in vitro model, that the extent of spreading of macrophages on different materials is a marker of activation, and that a soluble inducer has a dose-response effect on the secretion of cytokines in the culture medium. This work investigates the expression of three different cell surface markers [macrophages MAC-1, MAC-3 and intercellular adhesion molecule-1 (ICAM-1)] on macrophages in vitro using confocal microscopy and shows that ICAM-1 is also a marker of macrophage activation in this model. We observed increased amounts of ICAM-1 on activated macrophages compared to unactivated macrophages, whereas MAC-1 and MAC-3 were either expressed constitutively or demonstrated no quantitative change in expression after activation under the same experimental conditions. We also tested the expression of ICAM-1 with various concentrations of soluble inducers (lipopolysaccharide, 0.001, 0.01, 0.1, 1 and 10 micrograms ml-1. S-27609, 0.1, 0.25, 0.5, 1, 2 and 3 micrograms ml-1 and on a sheet of polylactic acid alone or in combination with soluble inducers. All doses of soluble inducers induced the expression of ICAM-1 on cells grown in glass chamber slides. The induction was not dose related but seemed to work rather in an on-off manner. There was no effect of material on ICAM-1 expression on the cell surface when no soluble inducer was added. This was similar to cytokine secretion, which was not induced by our material alone. When either lipopolysaccharide or S-27609 was used in combination with the material, there was an increase in the average measured intensity of ICAM-1. In this in vitro model, ICAM-1 staining as measured by confocal microscopy is a marker for macrophage activation. Our results suggest that the extent of macrophage activation as measured by ICAM-1 and by

  10. Glial cell line-derived neurotrophic factor (GDNF) induces neuritogenesis in the cochlear spiral ganglion via neural cell adhesion molecule (NCAM).

    PubMed

    Euteneuer, Sara; Yang, Kuo H; Chavez, Eduardo; Leichtle, Anke; Loers, Gabriele; Olshansky, Adel; Pak, Kwang; Schachner, Melitta; Ryan, Allen F

    2013-05-01

    Glial cell line-derived neurotrophic factor (GDNF) increases survival and neurite extension of spiral ganglion neurons (SGNs), the primary neurons of the auditory system, via yet unknown signaling mechanisms. In other cell types, signaling is achieved by the GPI-linked GDNF family receptor α1 (GFRα1) via recruitment of transmembrane receptors: Ret (re-arranged during transformation) and/or NCAM (neural cell adhesion molecule). Here we show that GDNF enhances neuritogenesis in organotypic cultures of spiral ganglia from 5-day-old rats and mice. Addition of GFRα1-Fc increases this effect. GDNF/GFRα1-Fc stimulation activates intracellular PI3K/Akt and MEK/Erk signaling cascades as detected by Western blot analysis of cultures prepared from rats at postnatal days 5 (P5, before the onset of hearing) and 20 (P20, after the onset of hearing). Both cascades mediate GDNF stimulation of neuritogenesis, since application of the Akt inhibitor Wortmannin or the Erk inhibitor U0126 abolished GDNF/GFRα1-Fc stimulated neuritogenesis in P5 rats. Since cultures of P5 NCAM-deficient mice failed to respond by neuritogenesis to GDNF/GFRα1-Fc, we conclude that NCAM serves as a receptor for GDNF signaling responsible for neuritogenesis in early postnatal spiral ganglion.

  11. The Microbial Surface Components Recognizing Adhesive Matrix Molecules (MSCRAMMs) Genes among Clinical Isolates of Staphylococcus aureus from Hospitalized Children

    PubMed Central

    Ghasemian, Abdolmajid; Najar Peerayeh, Shahin; Bakhshi, Bita; Mirzaee, Mohsen

    2015-01-01

    Background: Isolates of Staphylococcus aureus express a myriad of adhesive surface proteins that play important role in colonization of the bacteria on nasal and skin surfaces, beginning the process of pathogenesis. The aim of this study was to screen several of the Microbial Surface Components Recognizing Adhesive Matrix Molecules (MSCRAMMs) genes among the isolate of S. aureus from hospitalized children. Methods: A total of 22 S. aureus isolates were collected from hospitalized children in Tehran from 2012 to 2013. Detection of the mecA and several adhesive surface proteins genes including clfA, B (encoding clumping factors A, B); fnbA, B (encoding finronectin binding proteins A, B); fib (encoding fibrinogen binding protein); eno (encoding laminin binding protein); cna (encoding collagen binding protein); ebps (encoding elastin binding protein) and bbp (encoding bone sialo-protein binding protein), was performed by PCR. Results: The clfAB genes were detected among all the isolates. The prevalence of fnbA, fnbB, fib, eno, cna, ebps and bbp was 63%, 6%, 50%, 59%, 82%, 63%, 9% and 0%, respectively. Conclusion: The high prevalence of these genes is important for future plans in vaccine designation. MRSA and MSSA isolates similarly can produce adhesive surface proteins for colonization. PMID:26351495

  12. Targeted Gene Deletion Demonstrates that Cell Adhesion MoleculeICAM-4 is Critical for Erythroblastic Island Formation

    SciTech Connect

    Lee, Gloria; Lo, Annie; Short, Sarah A.; Mankelow, Tosti J.; Spring, Frances; Parsons, Stephen F.; Mohandas, Narla; Anstee, David J.; Chasis, Joel Anne

    2006-02-15

    Erythroid progenitors differentiate in erythroblastic islands, bone marrow niches composed of erythroblasts surrounding a central macrophage. Evidence suggests that within islands adhesive interactions regulate erythropoiesis and apoptosis. We are exploring whether erythroid intercellular adhesion molecule-4 (ICAM-4), animmunoglobulin superfamily member, participates in island formation. Earlier, we identified alpha V integrins as ICAM-4 counter receptors. Since macrophages express alpha V, ICAM-4 potentially mediates island attachments. To test this, we generated ICAM-4 knockout mice and developed quantitative, live cell techniques for harvesting intact islands and for reforming islands in vitro. We observed a 47 percent decrease in islands reconstituted from ICAM-4 null marrow compared to wild type. We also found a striking decrease in islands formed in vivo in knockout mice. Further, peptides that block ICAM-4 alpha V adhesion produced a 53-57 percent decrease in reconstituted islands, strongly suggesting that ICAM-4 binding to macrophage alpha V functions in island integrity. Importantly, we documented that alpha V integrin is expressed in macrophages isolated from erythro blastic islands. Collectively, these data provide convincing evidence that ICAM-4 is critical in erythroblastic island formation via ICAM-4/alpha V adhesion and also demonstrate that the novel experimental strategies we developed will be valuable in exploring molecular mechanisms of erythroblastic island formation and their functional role in regulating erythropoiesis.

  13. Obstructive jaundice causes reduced expression of polymorphonuclear leucocyte adhesion molecules and a depressed response to bacterial wall products in vitro.

    PubMed Central

    Plusa, S; Webster, N; Primrose, J

    1996-01-01

    BACKGROUND--Obstructive jaundice is associated with an increased incidence of infection and endotoxaemia, which may result from impaired host immunity. Neutrophil adhesion to vascular endothelium is a key part of the inflammatory response. AIMS--To investigate neutrophil adhesion molecule expression and activation in obstructive jaundice. PATIENTS--Nine adult patients with obstructive jaundice and 11 control subjects. METHODS--The expression of the neutrophil adhesion receptors L-selectin, CD11a, CD11b, CD11c, and CD15 was determined using flow cytometry. CD11b expression in response to stimulation with fMLP and endotoxin was measured. RESULTS--The basal expression of L-selectin, CD11a, and CD15 was significantly decreased in jaundiced patients (p < 0.05) and the expression of CD11b in response to stimulation with fMLP and endotoxin was significantly impaired in the jaundiced group. Endotoxin stimulation without plasma did not reverse the impaired response showing that it is not caused by endotoxin inactivation by plasma proteins. CONCLUSIONS--Neutrophils from patients with obstructive jaundice show decreased adhesion receptor expression and an impaired response to stimulation with bacterial products. This cellular dysfunction may be responsible for the high incidence of septic complications in these patients. PMID:8707129

  14. Monocyte exosomes induce adhesion molecules and cytokines via activation of NF-κB in endothelial cells.

    PubMed

    Tang, Norina; Sun, Bing; Gupta, Archana; Rempel, Hans; Pulliam, Lynn

    2016-09-01

    HIV-infected individuals have activated monocytes with an IFNα phenotype and elevated levels of circulating LPS. These individuals also have a risk of premature cardiovascular disease. The effect of activated monocyte exosomes (Exos) on endothelial cells is unknown. To determine whether Exos from immune-activated monocytes could alter endothelial cell expression and contribute to monocyte/macrophage transmigration and adhesion, we isolated Exos from monocytes stimulated with IFNα, LPS, or both (I/L). We show that monocyte Exos contain different inflammatory microRNA cargo depending on stimulation. When LPS Exos or I/L Exos were added to HUVECs, we found a significant increase in adhesion molecule ICAM-1, chemokine ligand (CCL)-2, and cytokine IL-6 mRNAs and proteins compared with cells treated with IFNα Exos or Exos derived from unstimulated monocytes. Inhibition of transcription factor NF-κB, a common inflammatory cytokine pathway, prevented induction of CCL2, IL6, and ICAM1 Inhibition of TLR4 resulted in differential blockage of the targets. Our results demonstrate for the first time that primary human monocyte Exos enter endothelial cells and cause dysfunction via the TLR4 and NF-κB pathways, which may contribute to heart disease in HIV infection and other diseases involving chronic immune activation.-Tang, N., Sun, B., Gupta, A., Rempel, H., Pulliam, L. Monocyte exosomes induce adhesion molecules and cytokines via activation of NF-κB in endothelial cells. PMID:27226520

  15. 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.

  16. Ligation of MHC class I and class II molecules can lead to heterologous desensitization of signal transduction pathways that regulate homotypic adhesion in human lymphocytes.

    PubMed

    Wagner, N; Engel, P; Vega, M; Tedder, T F

    1994-06-01

    Engagement of lymphocyte MHC class I and class II Ags activates an array of intracellular signal transduction pathways that up-regulates the activity of cell-surface adhesion receptors, resulting in homotypic cell-cell aggregation. In this study, engagement of MHC class I and class II molecules with specific mAbs was shown to also inhibit lymphocyte homotypic adhesion. Two mAbs reactive with class II Ag, homotypic adhesion blocking mAb (HAB)-2, and HAB-3, and one mAb reactive with class I Ag, HAB-4, were generated that inhibited homotypic adhesion of activated lymphocytes and B and T cell lines at concentrations as low as 0.1 microgram/ml. Binding of these mAbs resulted in heterologous desensitization of other surface signal transduction molecules as homotypic adhesion induced through class I, class II, CD19, CD20, CD39, CD40, Leu-13, and PMA was also inhibited. The spontaneous adhesion exhibited by some cell lines was also abrogated by binding of these mAbs. Abs that either induced, blocked, or had no effect on adhesion bound to distinct epitopes on class I, whereas the anti-class II mAbs recognized either distinct or overlapping epitopes. Thus, engagement of distinct epitopes on MHC molecules can result in homologous or heterologous desensitization of cell-surface signaling molecules. The induction or inhibition of homotypic adhesion through class I molecules did not require the presence of the cytoplasmic domain, as deletion of this portion of the class I molecule had no effect. In contrast, the transmembrane region was essential for signal transduction as the mAbs binding to a chimeric molecule in which the transmembrane and cytoplasmic domains of class I were exchanged with those of the HB15 molecule did not induce or inhibit homotypic adhesion. Although this report is the first demonstration that homotypic adhesion can be influenced in a negative manner through MHC molecules, these findings demonstrate a considerable level of cross-talk between MHC molecules

  17. A novel mechanism by which small molecule inhibitors induce the DFG flip in Aurora A

    PubMed Central

    Martin, Mathew P.; Zhu, Jin-Yi; Lawrence, Harshani R.; Pireddu, Roberta; Luo, Yunting; Alam, Riazul; Ozcan, Sevil; Sebti, Said M.; Lawrence, Nicholas J.; Schönbrunn, Ernst

    2015-01-01

    Most protein kinases share a DFG (Asp-Phe-Gly) motif in the ATP site which can assume two distinct conformations, the active DFG-in and the inactive DFG-out states. Small molecule inhibitors able to induce the DFG-out state have received considerable attention in kinase drug discovery. Using a typical DFG-in inhibitor scaffold of Aurora A, a kinase involved in the regulation of cell division, we found that halogen and nitrile substituents directed at the N-terminally flanking residue Ala273 induced global conformational changes in the enzyme, leading to DFG-out inhibitors that are among the most potent Aurora A inhibitors reported to date. The data suggest an unprecedented mechanism of action, in which induced-dipole forces along the Ala273 side chain alter the charge distribution of the DFG backbone, allowing the DFG to unwind. As the ADFG sequence and three-dimensional structure is highly conserved, DFG-out inhibitors of other kinases may be designed by specifically targeting the flanking alanine residue with electric dipoles. PMID:22248356

  18. A SMALL MOLECULE SCREEN IDENTIFIES SELECTIVE INHIBITORS OF UREA TRANSPORTER UT-A

    PubMed Central

    Esteva-Font, Cristina; Phuan, Puay-Wah; Anderson, Marc O.; Verkman, A.S.

    2013-01-01

    SUMMARY Urea transporter (UT) proteins, including UT-A in kidney tubule epithelia and UT-B in vasa recta microvessels, facilitate urinary concentrating function. A screen for UT-A inhibitors was developed in MDCK cells expressing UT-A1, water channel aquaporin-1, and YFP-H148Q/V163S. An inwardly directed urea gradient produces cell shrinking followed by UT-A1-dependent swelling, which was monitored by YFP-H148Q/V163S fluorescence. Screening of ~90,000 synthetic small molecules yielded four classes of UT-A1 inhibitors with low micromolar IC50 that fully and reversibly inhibited urea transport by a non-competitive mechanism. Structure-activity analysis of >400 analogs revealed UT-A1-selective and UT-A1/UT-B non-selective inhibitors. Docking computations based on homology models of UT-A1 suggested inhibitor binding sites. UT-A inhibitors may be useful as diuretics (‘urearetics’) with a novel mechanism of action that may be effective in fluid-retaining conditions in which conventional salt transport-blocking diuretics have limited efficacy. PMID:24055006

  19. Urearetics: a small molecule screen yields nanomolar potency inhibitors of urea transporter UT-B.

    PubMed

    Levin, Marc H; de la Fuente, Ricardo; Verkman, A S

    2007-02-01

    Functional studies in knockout mice indicate a critical role for urea transporters (UTs) in the urinary concentrating mechanism and in renal urea clearance. However, potent and specific urea transport blockers have not been available. Here, we used high-throughput screening to discover high-affinity, small molecule inhibitors of the UT-B urea transporter. A collection of 50,000 diverse, drug-like compounds was screened using a human erythrocyte lysis assay based on UT-B-facilitated acetamide transport. Primary screening yielded approximately 30 UT-B inhibitors belonging to the phenylsulfoxyoxazole, benzenesulfonanilide, phthalazinamine, and aminobenzimidazole chemical classes. Screening of approximately 700 structurally similar analogs gave many active compounds, the most potent of which inhibited UT-B urea transport with an EC50 of approximately 10 nM, and approximately 100% inhibition at higher concentrations. Phenylsulfoxyoxazoles and phthalazinamines also blocked rodent UT-B and had good UT-B vs. UT-A specificity. The UT-B inhibitors did not reduce aquaporin-1 (AQP1)-facilitated water transport. In AQP1-null erythrocytes, "chemical UT-B knockout" by UT-B inhibitors reduced by approximately 3-fold UT-B-mediated water transport, supporting an aqueous pore pathway through UT-B. UT-B inhibitors represent a new class of diuretics, "urearetics," which are predicted to increase renal water and solute clearance in water-retaining states.

  20. The P2Y2 nucleotide receptor mediates UTP-induced vascular cell adhesion molecule-1 expression in coronary artery endothelial cells.

    PubMed

    Seye, Cheikh I; Yu, Ningpu; Jain, Renu; Kong, Qiongman; Minor, Tess; Newton, Jessica; Erb, Laurie; González, Fernando A; Weisman, Gary A

    2003-07-01

    P2Y2 receptor up-regulation and activation induces intimal hyperplasia and monocyte/macrophage infiltration in the collared rabbit carotid artery model of vascular injury, suggesting a potential role for P2Y2 receptors in monocyte recruitment by vascular endothelium. In this study, we addressed the hypothesis that activation of P2Y2 receptors by extracellular nucleotides modulates the expression of adhesion molecules on vascular endothelial cells that are important for monocyte recruitment. Results indicated that the equipotent P2Y2 receptor agonists UTP or ATP (1-100 microm) stimulated the expression of vascular cell adhesion molecule-1 (VCAM-1) in human coronary artery endothelial cells (HCAEC) in a time- and dose-dependent manner. P2Y2 antisense oligonucleotides inhibited VCAM-1 expression induced by UTP but not by tumor necrosis factor-alpha. Furthermore, UTP induced VCAM-1 expression in human 1321N1 astrocytoma cell transfectants expressing the recombinant P2Y2 receptor, whereas vector-transfected control cells did not respond to UTP. The effect of UTP on VCAM-1 expression in HCAEC was prevented by depletion of intracellular calcium stores with thapsigargin or by inhibition of p38 mitogen-activated protein kinase or Rho kinase, but was not affected by inhibitors of the mitogen-activated protein/extracellular signal-regulated kinase pathway (i.e. MEK1/2). Consistent with a role for VCAM-1 in the recruitment of monocytes, UTP or ATP increased the adherence of monocytic U937 cells to HCAEC, an effect that was inhibited by anti-VCAM-1 antibodies. These findings suggest a novel role for the P2Y2 receptor in the p38- and Rho kinase-dependent expression of VCAM-1 that mediates the recruitment of monocytes by vascular endothelium associated with the development of atherosclerosis.

  1. Cathepsin E generates a sumoylated intracellular fragment of the cell adhesion molecule L1 to promote neuronal and Schwann cell migration as well as myelination.

    PubMed

    Lutz, David; Wolters-Eisfeld, Gerrit; Schachner, Melitta; Kleene, Ralf

    2014-03-01

    The cell adhesion molecule L1 regulates cellular responses in the developing and adult nervous system. Here, we show that stimulation of cultured mouse cerebellar neurons by a function-triggering L1 antibody leads to cathepsin E-mediated generation of a sumoylated 30 kDa L1 fragment (L1-30) and to import of L1-30 into the nucleus. Mutation of the sumoylation site at K1172 or the cathepsin E cleavage site at E1167 abolishes generation of L1-30, while mutation of the nuclear localization signal at K1147 prevents nuclear import of L1-30. Moreover, the aspartyl protease inhibitor pepstatin impairs the generation of L1-30 and inhibits L1-induced migration of cerebellar neurons and Schwann cells as well as L1-dependent in vitro myelination on axons of dorsal root ganglion neurons by Schwann cells. L1-stimulated migration of HEK293 cells expressing L1 with mutated cathepsin E cleavage site is diminished in comparison to migration of cells expressing non-mutated L1. In addition, L1-stimulated migration of HEK293 cells expressing non-mutated L1 is also abolished upon knock-down of cathepsin E expression and enhanced by over-expression of cathepsin E. The findings of the present study indicate that generation and nuclear import of L1-30 regulate neuronal and Schwann cell migration as well as myelination. Cell adhesion molecule L1 regulates cellular responses in the developing and adult nervous system. L1 stimulation triggers sumoylation and cleavage of L1, thus generating the L1-70 fragment (1) which is cleaved by cathepsin E (2) yielding the L1-30 fragment that is imported to the nucleus (3), may bind to DNA and/or nuclear proteins (4), to regulate diverse cellular functions. PMID:24118054

  2. Optimization of important early ADME(T) parameters of NADPH oxidase-4 inhibitor molecules.

    PubMed

    Borbély, Gábor; Huszár, Ménika; Varga, Attila; Futosi, Krisztina; Mócsai, Attila; Orfi, László; Idei, Miklós; Mandl, József; Kéri, György; Vántus, Tibor

    2012-03-01

    Through their reactive oxygen species (ROS) producing function, NADPH oxidase (NOX) enzymes have been linked to several oxidative stress related diseases. In our recently published paper [1] we have already shown the NOX4 inhibitory effect of diverse, molecule sub-libraries and their biological importance. We also presented our work connected to potential anti-tumour molecules and the relationship between their biological activity and physico-chemical properties [2]. As an extension of these studies further physico-chemical and biological investigation has been carried out on a molecule group included NOX4 inhibitory chromanone compounds. Here we describe the optimization of early ADME(T) parameters determining lipophilicity, phospholipophilicity and permeability linked to structure-activity relationship. We prove that optimal lipo- and phospholipophilicty can be also determined in case of NOX4 inhibitors and a comparison will be made between the chemically similar isochromanone and chromanone molecular libraries. It will be also shown how to predict the effect of different substituents on permeability, lipo- and phospholipophilicity and also the biological differences between anti-tumour molecules and NOX4 inhibitors according to their penetration ability.

  3. S fimbriae of uropathogenic Escherichia coli bind to primary human renal proximal tubular epithelial cells but do not induce expression of intercellular adhesion molecule 1.

    PubMed Central

    Kreft, B; Placzek, M; Doehn, C; Hacker, J; Schmidt, G; Wasenauer, G; Daha, M R; van der Woude, F J; Sack, K

    1995-01-01

    We have recently reported an increase of expression of the intercellular adhesion molecule 1 by renal carcinoma cells in response to S fimbriae of Escherichia coli. Now we demonstrate that E. coli expressing S and P fimbriae strongly binds to human proximal tubular epithelial cells. However, in primary and simian virus 40-transfected renal tubular epithelial cells S fimbriae do not enhance the expression of intercellular adhesion molecule 1. PMID:7622256

  4. Discovery of small molecule inhibitors of xyloglucan endotransglucosylase (XET) activity by high-throughput screening

    PubMed Central

    Chormova, Dimitra; Franková, Lenka; Defries, Andrew; Cutler, Sean R.; Fry, Stephen C.

    2015-01-01

    Small molecules (xenobiotics) that inhibit cell-wall-localised enzymes are valuable for elucidating the enzymes’ biological roles. We applied a high-throughput fluorescent dot-blot screen to search for inhibitors of Petroselinum xyloglucan endotransglucosylase (XET) activity in vitro. Of 4216 xenobiotics tested, with cellulose-bound xyloglucan as donor-substrate, 18 inhibited XET activity and 18 promoted it (especially anthraquinones and flavonoids). No compounds promoted XET in quantitative assays with (cellulose-free) soluble xyloglucan as substrate, suggesting that promotion was dependent on enzyme–cellulose interactions. With cellulose-free xyloglucan as substrate, we found 22 XET-inhibitors – especially compounds that generate singlet oxygen (1O2) e.g., riboflavin (IC50 29 μM), retinoic acid, eosin (IC50 27 μM) and erythrosin (IC50 36 μM). The riboflavin effect was light-dependent, supporting 1O2 involvement. Other inhibitors included tannins, sulphydryl reagents and triphenylmethanes. Some inhibitors (vulpinic acid and brilliant blue G) were relatively specific to XET, affecting only two or three, respectively, of nine other wall-enzyme activities tested; others [e.g. (−)-epigallocatechin gallate and riboflavin] were non-specific. In vivo, out of eight XET-inhibitors bioassayed, erythrosin (1 μM) inhibited cell expansion in Rosa and Zea cell-suspension cultures, and 40 μM mycophenolic acid and (−)-epigallocatechin gallate inhibited Zea culture growth. Our work showcases a general high-throughput strategy for discovering wall-enzyme inhibitors, some being plant growth inhibitors potentially valuable as physiological tools or herbicide leads. PMID:26093490

  5. Discovery of small molecule inhibitors of xyloglucan endotransglucosylase (XET) activity by high-throughput screening.

    PubMed

    Chormova, Dimitra; Franková, Lenka; Defries, Andrew; Cutler, Sean R; Fry, Stephen C

    2015-09-01

    Small molecules (xenobiotics) that inhibit cell-wall-localised enzymes are valuable for elucidating the enzymes' biological roles. We applied a high-throughput fluorescent dot-blot screen to search for inhibitors of Petroselinum xyloglucan endotransglucosylase (XET) activity in vitro. Of 4216 xenobiotics tested, with cellulose-bound xyloglucan as donor-substrate, 18 inhibited XET activity and 18 promoted it (especially anthraquinones and flavonoids). No compounds promoted XET in quantitative assays with (cellulose-free) soluble xyloglucan as substrate, suggesting that promotion was dependent on enzyme-cellulose interactions. With cellulose-free xyloglucan as substrate, we found 22 XET-inhibitors - especially compounds that generate singlet oxygen ((1)O2) e.g., riboflavin (IC50 29 μM), retinoic acid, eosin (IC50 27 μM) and erythrosin (IC50 36 μM). The riboflavin effect was light-dependent, supporting (1)O2 involvement. Other inhibitors included tannins, sulphydryl reagents and triphenylmethanes. Some inhibitors (vulpinic acid and brilliant blue G) were relatively specific to XET, affecting only two or three, respectively, of nine other wall-enzyme activities tested; others [e.g. (-)-epigallocatechin gallate and riboflavin] were non-specific. In vivo, out of eight XET-inhibitors bioassayed, erythrosin (1 μM) inhibited cell expansion in Rosa and Zea cell-suspension cultures, and 40 μM mycophenolic acid and (-)-epigallocatechin gallate inhibited Zea culture growth. Our work showcases a general high-throughput strategy for discovering wall-enzyme inhibitors, some being plant growth inhibitors potentially valuable as physiological tools or herbicide leads. PMID:26093490

  6. Structure of a Small-Molecule Inhibitor of a DNA Polymerase Sliding Clamp

    SciTech Connect

    Georgescu, R.; Yurieva, O; Kim, S; Kuriyan, J; Kong, X; O'Donnell, M

    2008-01-01

    DNA polymerases attach to the DNA sliding clamp through a common overlapping binding site. We identify a small-molecule compound that binds the protein-binding site in the Escherichia coli ?-clamp and differentially affects the activity of DNA polymerases II, III, and IV. To understand the molecular basis of this discrimination, the cocrystal structure of the chemical inhibitor is solved in complex with ? and is compared with the structures of Pol II, Pol III, and Pol IV peptides bound to ?. The analysis reveals that the small molecule localizes in a region of the clamp to which the DNA polymerases attach in different ways. The results suggest that the small molecule may be useful in the future to probe polymerase function with ?, and that the ?-clamp may represent an antibiotic target.

  7. Systems-based discovery of tomatidine as a natural small molecule inhibitor of skeletal muscle atrophy.

    PubMed

    Dyle, Michael C; Ebert, Scott M; Cook, Daniel P; Kunkel, Steven D; Fox, Daniel K; Bongers, Kale S; Bullard, Steven A; Dierdorff, Jason M; Adams, Christopher M

    2014-05-23

    Skeletal muscle atrophy is a common and debilitating condition that lacks an effective therapy. To address this problem, we used a systems-based discovery strategy to search for a small molecule whose mRNA expression signature negatively correlates to mRNA expression signatures of human skeletal muscle atrophy. This strategy identified a natural small molecule from tomato plants, tomatidine. Using cultured skeletal myotubes from both humans and mice, we found that tomatidine stimulated mTORC1 signaling and anabolism, leading to accumulation of protein and mitochondria, and ultimately, cell growth. Furthermore, in mice, tomatidine increased skeletal muscle mTORC1 signaling, reduced skeletal muscle atrophy, enhanced recovery from skeletal muscle atrophy, stimulated skeletal muscle hypertrophy, and increased strength and exercise capacity. Collectively, these results identify tomatidine as a novel small molecule inhibitor of muscle atrophy. Tomatidine may have utility as a therapeutic agent or lead compound for skeletal muscle atrophy. PMID:24719321

  8. Rational design and applications of a Rac GTPase-specific small molecule inhibitor.

    PubMed

    Akbar, Huzoor; Cancelas, Jose; Williams, David A; Zheng, Jie; Zheng, Yi

    2006-01-01

    Rac GTPases are involved in the regulation of multiple cell functions and have been implicated in the pathology of certain human diseases. Dominant negative mutants of Rac have been the tool of choice in studying Rac function in cells. Given the difficulty of introducing high concentrations of the Rac mutants into primary cells and nonspecific effects of the mutants on Rho guanine nucleotide exchange factor (GEF) activities, it is desirable to develop small molecule inhibitors that could specifically inhibit Rac activities. Here we describe the rational design, characterization, and applications of a first-generation Rac-specific small molecule inhibitor. On the basis of the structure-function information of Rac interaction with GEFs, in a computer-based virtual screening we have identified NSC23766, a highly soluble and membrane permeable compound, as a specific inhibitor of a subset of GEF binding to Rac and, therefore, Rac activation by these GEFs. In fibroblast cells, NSC23766 inhibited Rac1 GTP-loading without affecting Cdc42 or RhoA activity and suppressed cell proliferation induced by a Rac GEF Tiam1. It has little effect on cell growth induced by a constitutively active Rac1 mutant. In addition, NSC23766 inhibited: (1) the anchorage-independent growth and invasion phenotypes of human prostate cancer PC-3 cells; (2) Rac activation and Rac-dependent aggregation of platelets stimulated by thrombin; and (3) Rac1 and Rac2 activities of hematopoietic stem/progenitor cells and induced their mobilization from mouse bone marrow to peripheral blood. Thus, NSC23766 is a lead small molecule inhibitor of Rac activity and could be useful for studying Rac-mediated cellular functions and for modulating pathological conditions in which Rac-deregulation may play a role.

  9. Discovery of GSK2795039, a Novel Small Molecule NADPH Oxidase 2 Inhibitor

    PubMed Central

    Hirano, Kazufumi; Chen, Woei Shin; Chueng, Adeline L.W.; Dunne, Angela A.; Seredenina, Tamara; Filippova, Aleksandra; Ramachandran, Sumitra; Bridges, Angela; Chaudry, Laiq; Pettman, Gary; Allan, Craig; Duncan, Sarah; Lee, Kiew Ching; Lim, Jean; Ma, May Thu; Ong, Agnes B.; Ye, Nicole Y.; Nasir, Shabina; Mulyanidewi, Sri; Aw, Chiu Cheong; Oon, Pamela P.; Liao, Shihua; Li, Dizheng; Johns, Douglas G.; Miller, Neil D.; Davies, Ceri H.; Browne, Edward R.; Matsuoka, Yasuji; Chen, Deborah W.; Jaquet, Vincent

    2015-01-01

    Abstract Aims: The NADPH oxidase (NOX) family of enzymes catalyzes the formation of reactive oxygen species (ROS). NOX enzymes not only have a key role in a variety of physiological processes but also contribute to oxidative stress in certain disease states. To date, while numerous small molecule inhibitors have been reported (in particular for NOX2), none have demonstrated inhibitory activity in vivo. As such, there is a need for the identification of improved NOX inhibitors to enable further evaluation of the biological functions of NOX enzymes in vivo as well as the therapeutic potential of NOX inhibition. In this study, both the in vitro and in vivo pharmacological profiles of GSK2795039, a novel NOX2 inhibitor, were characterized in comparison with other published NOX inhibitors. Results: GSK2795039 inhibited both the formation of ROS and the utilization of the enzyme substrates, NADPH and oxygen, in a variety of semirecombinant cell-free and cell-based NOX2 assays. It inhibited NOX2 in an NADPH competitive manner and was selective over other NOX isoforms, xanthine oxidase, and endothelial nitric oxide synthase enzymes. Following systemic administration in mice, GSK2795039 abolished the production of ROS by activated NOX2 enzyme in a paw inflammation model. Furthermore, GSK2795039 showed activity in a murine model of acute pancreatitis, reducing the levels of serum amylase triggered by systemic injection of cerulein. Innovation and Conclusions: GSK2795039 is a novel NOX2 inhibitor that is the first small molecule to demonstrate inhibition of the NOX2 enzyme in vivo. Antioxid. Redox Signal. 23, 358–374. PMID:26135714

  10. Evaluation of small molecule SecA inhibitors against methicillin-resistant Staphylococcus aureus.

    PubMed

    Jin, Jinshan; Cui, Jianmei; Chaudhary, Arpana Sagwal; Hsieh, Ying-Hsin; Damera, Krishna; Zhang, Hao; Yang, Hsiuchin; Wang, Binghe; Tai, Phang C

    2015-11-01

    Due to the emergence and rapid spread of drug resistance in bacteria, there is an urgent need for the development of novel antimicrobials. SecA, a key component of the general bacterial secretion system required for viability and virulence, is an attractive antimicrobial target. Earlier we reported that systematical dissection of a SecA inhibitor, Rose Bengal (RB), led to the development of novel small molecule SecA inhibitors active against Escherichia coli and Bacillus subtilis. In this study, two potent RB analogs were further evaluated for activities against methicillin-resistant Staphylococcus aureus (MRSA) strains and for their mechanism of actions. These analogs showed inhibition on the ATPase activities of S. aureus SecA1 (SaSecA1) and SecA2 (SaSecA2), and inhibition of SaSecA1-dependent protein-conducting channel. Moreover, these inhibitors reduce the secretion of three toxins from S. aureus and exert potent bacteriostatic effects against three MRSA strains. Our best inhibitor SCA-50 showed potent concentration-dependent bactericidal activity against MRSA Mu50 strain and very importantly, 2-60 fold more potent inhibitory effect on MRSA Mu50 than all the commonly used antibiotics including vancomycin, which is considered the last resort option in treating MRSA-related infections. Protein pull down experiments further confirmed SaSecA1 as a target. Deletion or overexpression of NorA and MepA efflux pumps had minimal effect on the antimicrobial activities against S. aureus, indicating that the effects of SecA inhibitors were not affected by the presence of these efflux pumps. Our studies show that these small molecule analogs target SecA functions, have potent antimicrobial activities, reduce the secretion of toxins, and have the ability to overcome the effect efflux pumps, which are responsible for multi-drug resistance. Thus, targeting SecA is an attractive antimicrobial strategy against MRSA.

  11. Effect of Cell Adhesion Molecules on the Neurite Outgrowth of Induced Pluripotent Stem Cell-Derived Dopaminergic Neurons.

    PubMed

    Peng, Su-Ping; Schachner, Melitta; Boddeke, Erik; Copray, Sjef

    2016-04-01

    Intrastriatal transplantation of dopaminergic neurons has been shown to be a potentially very effective therapeutic approach for the treatment of Parkinson's disease (PD). With the detection of induced pluripotent stem cells (iPSCs), an unlimited source of autologous dopaminergic (DA) neurons became available. Although the iPSC-derived dopaminergic neurons exhibited most of the fundamental dopaminergic characteristics, detailed analysis and comparison with primary DA neurons have shown some aberrations in the expression of genes involved in neuronal development and neurite outgrowth. The limited outgrowth of the iPSC-derived DA neurons may hamper their potential application in cell transplantation therapy for PD. In the present study, we examined whether the forced expression of L1 cell adhesion molecule (L1CAM) and polysialylated neuronal cell adhesion molecule (PSA-NCAM), via gene transduction, can promote the neurite formation and outgrowth of iPSC-derived DA neurons. In cultures on astrocyte layers, both adhesion factors significantly increased neurite formation of the adhesion factor overexpressing iPSC-derived DA neurons in comparison to control iPSC-derived DA neurons. The same tendency was observed when the DA neurons were plated on postnatal organotypic striatal slices; however, this effect did not reach statistical significance. Next, we examined the neurite outgrowth of the L1CAM- or PSA-NCAM-overexpressing iPSC-derived DA neurons after implantation in the striatum of unilaterally 6-hydroxydopamine (6-OHDA)-lesioned rats, the animal model for PD. Like the outgrowth on the organotypic striatal slices, no significant L1CAM- and PSA-NCAM-enforced neurite outgrowth of the implanted DA neurons was observed. Apparently, induced expression of L1CAM or PSA-NCAM in the iPSC-derived DA neurons cannot completely restore the neurite outgrowth potential that was reduced in these DA neurons as a consequence of epigenetic aberrations resulting from the i

  12. MicroRNA-8 promotes robust motor axon targeting by coordinate regulation of cell adhesion molecules during synapse development

    PubMed Central

    Lu, Cecilia S.; Zhai, Bo; Mauss, Alex; Landgraf, Matthias; Gygi, Stephen; Van Vactor, David

    2014-01-01

    Neuronal connectivity and specificity rely upon precise coordinated deployment of multiple cell-surface and secreted molecules. MicroRNAs have tremendous potential for shaping neural circuitry by fine-tuning the spatio-temporal expression of key synaptic effector molecules. The highly conserved microRNA miR-8 is required during late stages of neuromuscular synapse development in Drosophila. However, its role in initial synapse formation was previously unknown. Detailed analysis of synaptogenesis in this system now reveals that miR-8 is required at the earliest stages of muscle target contact by RP3 motor axons. We find that the localization of multiple synaptic cell adhesion molecules (CAMs) is dependent on the expression of miR-8, suggesting that miR-8 regulates the initial assembly of synaptic sites. Using stable isotope labelling in vivo and comparative mass spectrometry, we find that miR-8 is required for normal expression of multiple proteins, including the CAMs Fasciclin III (FasIII) and Neuroglian (Nrg). Genetic analysis suggests that Nrg and FasIII collaborate downstream of miR-8 to promote accurate target recognition. Unlike the function of miR-8 at mature larval neuromuscular junctions, at the embryonic stage we find that miR-8 controls key effectors on both sides of the synapse. MiR-8 controls multiple stages of synapse formation through the coordinate regulation of both pre- and postsynaptic cell adhesion proteins. PMID:25135978

  13. Polysialic acid-neural cell adhesion molecule in brain plasticity: from synapses to integration of new neurons.

    PubMed

    Gascon, Eduardo; Vutskits, Laszlo; Kiss, Jozsef Zoltan

    2007-11-01

    Isoforms of the neuronal cell adhesion molecule (NCAM) carrying the linear homopolymer of alpha 2,8-linked sialic acid (polysialic acid, PSA) have emerged as particularly attractive candidates for promoting plasticity in the nervous system. The large negatively charged PSA chain of NCAM is postulated to be a spacer that reduces adhesion forces between cells allowing dynamic changes in membrane contacts. Accumulating evidence also suggests that PSA-NCAM-mediated interactions lead to activation of intracellular signaling cascades that are fundamental to the biological functions of the molecule. An important role of PSA-NCAM appears to be during development, when its expression level is high and where it contributes to the regulation of cell shape, growth or migration. However, PSA-NCAM does persist in adult brain structures such as the hippocampus that display a high degree of plasticity where it is involved in activity-induced synaptic plasticity. Recent advances in the field of PSA-NCAM research have not only consolidated the importance of this molecule in plasticity processes but also suggest a role for PSA-NCAM in the regulation of higher cognitive functions and psychiatric disorders. In this review, we discuss the role and mode of actions of PSA-NCAM in structural plasticity as well as its potential link to cognitive processes.

  14. Biogenesis and fate of the cell-cell adhesion molecule, agglutinin, during gametogenesis and fertilization of Chlamydomonas reinhardtii

    SciTech Connect

    Hunnicutt, G.R.

    1989-01-01

    Fertilization in Chlamydomonas begins with the species-specific recognition and adhesion between gametes of opposite mating types via agglutinin molecules on the flagellar surface. This adhesion generates a cAMP-mediated sexual signal that initiates the subsequent events of call wall release, mating structure activation, and cell fusion. Although flagella of paired gametes remain attached to each other until the zygote forms, the process is dynamic. Engaged agglutinins rapidly become inactivated and turnover, requiring the constant supply of new agglutinins to replace the lost molecules. A population of cell body associated agglutinins has been postulated to the pool of agglutinins recruited during this turnover. Cell body agglutinins, therefore were identified, purified, localized within the cells and compared to flagellar agglutinins. The relationship between these two agglutinin populations was also examined. Cell body agglutinins were biochemically indistinguishable from the flagellar form with respect to their M{sub r}, sedimentation coefficient, and hydrophobicity elution properties. Functionally, however, these molecules were inactive in situ. The calculated surface density of agglutinins in the cell body and flagellar domains was similar and thus could not explain their functional difference, but two domains contiguous and yet distinctive suggested they may be separated by a functional barrier. To test this, a method was developed, using a monoclonal antibody and cycloheximide, that removed the flagellar agglutinins so movement between the domains could be monitored. Mobilization of agglutinins onto the flagella did not occur unless sexual signaling was induced with cAMP and papaverine.

  15. MicroRNA-8 promotes robust motor axon targeting by coordinate regulation of cell adhesion molecules during synapse development.

    PubMed

    Lu, Cecilia S; Zhai, Bo; Mauss, Alex; Landgraf, Matthias; Gygi, Stephen; Van Vactor, David

    2014-09-26

    Neuronal connectivity and specificity rely upon precise coordinated deployment of multiple cell-surface and secreted molecules. MicroRNAs have tremendous potential for shaping neural circuitry by fine-tuning the spatio-temporal expression of key synaptic effector molecules. The highly conserved microRNA miR-8 is required during late stages of neuromuscular synapse development in Drosophila. However, its role in initial synapse formation was previously unknown. Detailed analysis of synaptogenesis in this system now reveals that miR-8 is required at the earliest stages of muscle target contact by RP3 motor axons. We find that the localization of multiple synaptic cell adhesion molecules (CAMs) is dependent on the expression of miR-8, suggesting that miR-8 regulates the initial assembly of synaptic sites. Using stable isotope labelling in vivo and comparative mass spectrometry, we find that miR-8 is required for normal expression of multiple proteins, including the CAMs Fasciclin III (FasIII) and Neuroglian (Nrg). Genetic analysis suggests that Nrg and FasIII collaborate downstream of miR-8 to promote accurate target recognition. Unlike the function of miR-8 at mature larval neuromuscular junctions, at the embryonic stage we find that miR-8 controls key effectors on both sides of the synapse. MiR-8 controls multiple stages of synapse formation through the coordinate regulation of both pre- and postsynaptic cell adhesion proteins.

  16. Small-Molecule Inhibitors of the MDM2–p53 Protein–Protein Interaction (MDM2 Inhibitors) in Clinical Trials for Cancer Treatment

    PubMed Central

    2015-01-01

    Design of small-molecule inhibitors (MDM2 inhibitors) to block the MDM2–p53 protein–protein interaction has been pursued as a new cancer therapeutic strategy. In recent years, potent, selective, and efficacious MDM2 inhibitors have been successfully obtained and seven such compounds have been advanced into early phase clinical trials for the treatment of human cancers. Here, we review the design, synthesis, properties, preclinical, and clinical studies of these clinical-stage MDM2 inhibitors. PMID:25396320

  17. 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. PMID:26412140

  18. 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.

  19. Small Molecule Microarrays Enable the Identification of a Selective, Quadruplex-Binding Inhibitor of MYC Expression

    PubMed Central

    2015-01-01

    The transcription factor MYC plays a pivotal role in cancer initiation, progression, and maintenance. However, it has proven difficult to develop small molecule inhibitors of MYC. One attractive route to pharmacological inhibition of MYC has been the prevention of its expression through small molecule-mediated stabilization of the G-quadruplex (G4) present in its promoter. Although molecules that bind globally to quadruplex DNA and influence gene expression are well-known, the identification of new chemical scaffolds that selectively modulate G4-driven genes remains a challenge. Here, we report an approach for the identification of G4-binding small molecules using small molecule microarrays (SMMs). We use the SMM screening platform to identify a novel G4-binding small molecule that inhibits MYC expression in cell models, with minimal impact on the expression of other G4-associated genes. Surface plasmon resonance (SPR) and thermal melt assays demonstrated that this molecule binds reversibly to the MYC G4 with single digit micromolar affinity, and with weaker or no measurable binding to other G4s. Biochemical and cell-based assays demonstrated that the compound effectively silenced MYC transcription and translation via a G4-dependent mechanism of action. The compound induced G1 arrest and was selectively toxic to MYC-driven cancer cell lines containing the G4 in the promoter but had minimal effects in peripheral blood mononucleocytes or a cell line lacking the G4 in its MYC promoter. As a measure of selectivity, gene expression analysis and qPCR experiments demonstrated that MYC and several MYC target genes were downregulated upon treatment with this compound, while the expression of several other G4-driven genes was not affected. In addition to providing a novel chemical scaffold that modulates MYC expression through G4 binding, this work suggests that the SMM screening approach may be broadly useful as an approach for the identification of new G4-binding small

  20. Selective small molecule inhibitor of the Mycobacterium tuberculosis fumarate hydratase reveals an allosteric regulatory site

    PubMed Central

    Kasbekar, Monica; Fischer, Gerhard; Mott, Bryan T.; Yasgar, Adam; Hyvönen, Marko; Boshoff, Helena I. M.; Abell, Chris; Barry, Clifton E.; Thomas, Craig J.

    2016-01-01

    Enzymes in essential metabolic pathways are attractive targets for the treatment of bacterial diseases, but in many cases, the presence of homologous human enzymes makes them impractical candidates for drug development. Fumarate hydratase, an essential enzyme in the tricarboxylic acid (TCA) cycle, has been identified as one such potential therapeutic target in tuberculosis. We report the discovery of the first small molecule inhibitor, to our knowledge, of the Mycobacterium tuberculosis fumarate hydratase. A crystal structure at 2.0-Å resolution of the compound in complex with the protein establishes the existence of a previously unidentified allosteric regulatory site. This allosteric site allows for selective inhibition with respect to the homologous human enzyme. We observe a unique binding mode in which two inhibitor molecules interact within the allosteric site, driving significant conformational changes that preclude simultaneous substrate and inhibitor binding. Our results demonstrate the selective inhibition of a highly conserved metabolic enzyme that contains identical active site residues in both the host and the pathogen. PMID:27325754

  1. Enzyme- and transporter-mediated drug interactions with small molecule tyrosine kinase inhibitors.

    PubMed

    Shao, Jie; Markowitz, John S; Bei, Di; An, Guohua

    2014-12-01

    Among the novel and target-specific classes of anticancer drugs, small molecule tyrosine kinase inhibitors (TKIs) represent an extremely promising and rapidly expanding group. TKIs attack cancer-specific targets and therefore have a favorable safety profile. However, as TKIs are taken orally along with other medications on a daily basis, there is an elevated risk of potentially significant drug-drug interactions. Most TKIs are metabolized primarily through CYP3A4. In addition, many TKIs are also CYP3A4 inhibitors at the same time. In addition to drug metabolizing enzymes (DMEs), another determinant of TKI disposition are drug transporters. There is accumulating evidence showing that the majority of currently marketed TKIs interact with ATP-binding cassette transporters, particularly P-glycoprotein as well as Breast Cancer Resistance Protein and serve as both substrates and inhibitors. Considering the dual roles of TKIs on both DMEs and drug transporters, and the importance of these enzyme and transporters in drug disposition, the potential for enzyme- and transporter-mediated TKI-drug interactions in patients with cancer is an important consideration. This review provides a comprehensive overview of drug interactions with small molecule TKIs mediated by DMEs and drug transporters. The TKI-drug interactions with TKIs being victims and/or perpetrators are summarized.

  2. Targeting insulin amyloid assembly by small aromatic molecules: toward rational design of aggregation inhibitors.

    PubMed

    Levy-Sakin, Michal; Shreberk, Michal; Daniel, Yael; Gazit, Ehud

    2009-01-01

    Amyloid fibril formation is a common event in more than twenty human diseases and in some normal physiological processes. The mechanism of this ordered aggregation process and the molecular forces driving it are therefore of great importance. One of the strategies used in this field is targeting the fibrillization process by different factors, like, short peptides, organic molecules, etc. Here, we targeted insulin fibril formation by a range of small aromatic molecules, with different numbers of aromatic rings and various substituent groups. Using Thioflavin T fluorescence assay and transmission electron microscopy, we found that all dicyclic and tricyclic compounds in our screen were efficient inhibitors of insulin fibril formation. A common notion regarding amyloid inhibitors is that two functional groups are essentials for interfering with the amyloid formation process; a recognition motif and a bulky group for inducing a steric interference. However, here, we showed that some monocyclic compounds as small as toluene were also found to inhibit fibrillization. In addition, we found that substituent of benzene ring have a great influence on the inhibitory potency. Specifically, cyano, methyl and nitro groups increased the inhibitory potency. The results introduced here may contribute to future rational design of amyloid inhibitors.

  3. Aryl amide small-molecule inhibitors of microRNA miR-21 function.

    PubMed

    Naro, Yuta; Thomas, Meryl; Stephens, Matthew D; Connelly, Colleen M; Deiters, Alexander

    2015-11-01

    MicroRNAs (miRNAs) are single stranded RNA molecules of ∼22 nucleotides that negatively regulate gene expression. MiRNAs are involved in fundamental cellular processes, such as development, differentiation, proliferation, and survival. MiRNA misregulation has been linked to various human diseases, most notably cancer. MicroRNA-21 (miR-21), a well-established oncomiR, is significantly overexpressed in many types of human cancers, thus rendering miR-21 a potential therapeutic target. Using a luciferase-based reporter assay under the control of miR-21 expression, a high-throughput screen of >300,000 compounds led to the discovery of a new aryl amide class of small-molecule miR-21 inhibitors. Structure-activity relationship (SAR) studies resulted in the development of four aryl amide derivatives as potent and selective miR-21 inhibitors. The intracellular levels of various miRNAs in HeLa cells were analyzed by qRT-PCR revealing specificity for miR-21 inhibition over other miRNAs. Additionally, preliminary mechanism of action studies propose a different mode of action compared to previously reported miR-21 inhibitors, thus affording a new chemical probe for future studies.

  4. The identification of GPR3 inverse agonist AF64394; the first small molecule inhibitor of GPR3 receptor function.

    PubMed

    Jensen, Thomas; Elster, Lisbeth; Nielsen, Søren Møller; Poda, Suresh Babu; Loechel, Frosty; Volbracht, Christiane; Klewe, Ib Vestergaard; David, Laurent; Watson, Stephen P

    2014-11-15

    The identification of the novel and selective GPR3 inverse agonist AF64394, the first small molecule inhibitor of GPR3 receptor function, is described. Structure activity relationships and syntheses based around AF64394 are reported.

  5. Expression of epithelial cell adhesion molecule in carcinoma cells present in blood and primary and metastatic tumors.

    PubMed

    Rao, Chandra G; Chianese, David; Doyle, Gerald V; Miller, M Craig; Russell, Thomas; Sanders, Renouard A; Terstappen, Leon W M M

    2005-07-01

    The epithelial cell adhesion molecule (EpCAM) is involved in homophilic cell-cell adhesion in normal epithelia and is frequently overexpressed in primary and metastatic adenocarcinomas. It has been postulated that during detachment and dissemination of tumor cells, EpCAM may be down-regulated. Circulating tumor cells (CTC) may demonstrate this phenomenon as they have successfully escaped their local microenvironment and entered the circulation. EpCAM expression of CTC was compared to tumor cells in paraffin-embedded tissue arrays containing various benign diseases and carcinomas. EpCAM expression on CTC was determined by flow cytometry (FCM) and by immunohistochemistry (IHC) in paraffin-embedded tissue. To permit comparison of FCM results to those derived by IHC, EpCAM was quantified on cancer cell lines by FCM and then paraffin-embedded cell-blocks of these lines were used as staining guides for IHC analysis of tissue arrays. By IHC, 97% (384/397) of solid tissues analyzed had detectable EpCAM, with 72% of tissues showing antigen expression levels of > or =400,000 EpCAM molecules per cell. FCM analysis of CTC from 100 metastatic carcinoma patients with > or =2 CTC/90 microl blood showed EpCAM expression ranging from 9,900 to 246,000 (mean 49,700) antigens per cell. EpCAM expression was approximately 10-fold lower on CTC as compared to primary and metastatic tissues, suggesting that EpCAM expression is transient and dependent upon the local micro-environment. This supports the hypothesis that this adhesion molecule is down-regulated on carcinoma cells in the circulation.

  6. Chronic Restraint Stress Induces an Isoform-Specific Regulation on the Neural Cell Adhesion Molecule in the Hippocampus

    PubMed Central

    Touyarot, K.; Sandi, C.

    2002-01-01

    Existing evidence indicates that 21-days exposure of rats to restraint stress induces dendritic atrophy in pyramidal cells of the hippocampus. This phenomenon has been related to altered performance in hippocampal-dependent learning tasks. Prior studies have shown that hippocampal expression of cell adhesion molecules is modified by such stress treatment, with the neural cell adhesion molecule (NCAM) decreasing and L1 increasing, their expression, at both the mRNA and protein levels. Given that NCAM comprises several isoforms, we investigated here whether chronic stress might differentially affect the expression of the three major isoforms (NCAM-120, NCAM-140, NCAM-180) in the hippocampus. In addition, as glucocorticoids have been implicated in the deleterious effects induced by chronic stress, we also evaluated plasma corticosterone levels and the hippocampal expression of the corticosteroid mineralocorticoid receptor (MR) and glucocorticoid receptor (GR). The results showed that the protein concentration of the NCAM-140 isoform decreased in the hippoampus of stressed rats. This effect was isoform-specific, because NCAM-120 and NCAM-180 levels were not significantly modified. In addition, whereas basal levels of plasma corticosterone tended to be increased, MR and GR concentrations were not significantly altered. Although possible changes in NCAM-120, NCAM-180 and corticosteroid receptors at earlier time points of the stress period cannot be ignored; this study suggests that a down-regulation of NCAM-140 might be implicated in the structural alterations consistently shown to be induced in the hippocampus by chronic stress exposure. As NCAM-140 is involved in cell-cell adhesion and neurite outgrowth, these findings suggest that this molecule might be one of the molecular mechanisms involved in the complex interactions among neurodegeneration-related events. PMID:12757368

  7. Association of inflammatory cytokines and endothelial adhesion molecules with immunological, virological, and cardiometabolic disease in HIV-infected individuals.

    PubMed

    Lacerda, Heloísa Ramos; Falcão, Maria da Conceição Correia; de Albuquerque, Valéria Maria Gonçalves; Zírpoli, Josefina Claudia; Miranda-Filho, Demócrito de Barros; de Albuquerque, Maria de Fátima Pessoa Militão; Montarroyos, Ulisses; Ximenes, Ricardo Arraes de Alencar

    2014-05-01

    Elevated levels of inflammatory and endothelial biomarkers are related to chronic diseases, cancers, and cardiovascular disease. This study aimed at evaluating the association of inflammatory cytokines and endothelial adhesion molecules with immunological, virological, and cardiometabolic disease in HIV-infected individuals. A cross-sectional study was initiated to evaluate the association of CD4 lymphocyte count, viral load, antiretroviral therapy, and metabolic and cardiovascular disease with inflammatory cytokines [interleukin (IL)-1β, IL-6, and tumor necrosis factor α (TNF-α)], adhesion molecules [soluble intercellular Adhesion Molecule 1 (sICAM) and soluble Vascular Adhesion Molecule 1 (sVCAM)], and highsensitive C-reactive protein (hs-CRP) levels in 125 HIV-infected patients. The associations between independent variables and biomarkers were analyzed by means of multivariate logistic regression. A viral load ≥100,000 copies/mL had a stronger association with high levels of sVCAM-1 (P=0.026; OR=2.54; CI=1.12-5.78) and TNF-α (P=0.048; OR=2.42; CI=1.01-5.85) than the current viral load using a multivariate analysis. Antiretroviral treatment was associated with lower levels of sVCAM-1 (P=0.20; OR=0.20; CI=0.05-0.78), TNF-α (P=0.060; OR=0.22; CI=0.05-1.07), and hs-CRP (P=0.093; OR=0.44; CI=0.17-1.15). CD4 counts <200 cells/mm(3) were associated with high IL-6 levels (P=0.013; OR=3.17; CI=1.27-7.91); however, antiretroviral treatment was not associated with IL-6 levels. Metabolic syndrome was associated with high hs-CRP levels, systolic hypertension was associated with IL-6 levels, and family history of coronary disease was associated with TNF-α levels. High biomarker levels were associated not only with viral and immunological characteristics but also with cardiometabolic factors. The maximum viral load attained was an important risk factor for high levels of TNF-α and sVCAM-1. Treatment protected patients from high biomarker levels, except IL-6.

  8. Risk stratification in unstable angina and non-Q wave myocardial infarction using soluble cell adhesion molecules

    PubMed Central

    Mulvihill, N; Foley, J; Murphy, R; Curtin, R; Crean, P; Walsh, M

    2001-01-01

    OBJECTIVE—To assess prospectively the prognostic value of soluble cellular adhesion molecules (CAMs) in patients with unstable angina and non-Q wave myocardial infarction and to compare their prognostic accuracy with that of C reactive protein (CRP).
DESIGN AND SETTING—Prospective observational study of patients presenting acutely with unstable angina and non-Q wave myocardial infarction to a single south Dublin hospital.
METHODS—Patients with Braunwald IIIA unstable angina and non-Q wave myocardial infarction had serum samples taken at presentation before initiation of antithrombotic treatment and were followed for six months. The primary end point was the occurrence of major adverse cardiovascular events (recurrent unstable angina, non-fatal myocardial infarction, and cardiovascular death) at six months. Concentrations of soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble endothelial selectin, and soluble platelet selectin were measured using an enzyme linked immunosorbent assay technique. CRP was measured with an immunophelometric assay.
RESULTS—91 patients (73 men and 18 women, mean (SD) age 61 (11) years) were studied; 27 patients (30%) had major adverse cardiac events during the six months of follow up. Concentration of CRP were significantly raised in patients who had an ischaemic event (mean (SEM) 11.5 (6.4) mg/l v 5.4 (2.5) mg/l, p < 0.001). Concentrations of sVCAM-1 were also significantly raised in the ischaemic event group (979 (30) ng/ml v 729 (22) ng/ml, p < 0.001). Both sVCAM-1 and CRP concentrations correlated strongly with the occurrence of an adverse event. The sensitivity of CRP > 3 mg/l and sVCAM-1 > 780 ng/ml for predicting future events was > 90%. There was no difference in concentrations of sICAM-1, soluble endothelin selectin, or soluble platelet selectin between event and non-event groups.
CONCLUSION—Raised concentrations of sVCAM-1 and CRP

  9. Unraveling the Secrets of Bacterial Adhesion Organelles Using Single-Molecule Force Spectroscopy

    NASA Astrophysics Data System (ADS)

    Axner, Ove; Björnham, Oscar; Castelain, Mickaël; Koutris, Efstratios; Schedin, Staffan; Fällman, Erik; Andersson, Magnus

    Many types of bacterium express micrometer-long attachment organelles (so-called pili) whose role is to mediate adhesion to host tissue. Until recently, little was known about their function in the adhesion process. Force-measuring optical tweezers (FMOT) have since then been used to unravel the biomechanical properties of various types of pili, primarily those from uropathogenic E. coli, in particular their force-vs.-elongation response, but lately also some properties of the adhesin are situated at the distal end of the pilus. This knowledge provides an understanding of how piliated bacteria can sustain external shear forces caused by rinsing processes, e.g., urine flow. It has been found that many types of pilus exhibit unique and complex force-vs.-elongation responses. It has been conjectured that their dissimilar properties impose significant differences in their ability to sustain external forces and that different types of pilus therefore have dissimilar predisposition to withstand different types of rinsing conditions. An understanding of these properties is of high importance since it can serve as a basis for finding new means to combat bacterial adhesion, including that caused by antibiotic-resistance bacteria. This work presents a review of the current status of the assessment of biophysical properties of individual pili on single bacteria exposed to strain/stress, primarily by the FMOT technique. It also addresses, for the first time, how the elongation and retraction properties of the rod couple to the adhesive properties of the tip adhesin.

  10. Computer-assisted identification of novel small molecule inhibitors targeting GLUT1

    NASA Astrophysics Data System (ADS)

    Wan, Zhining; Li, Xin; Sun, Rong; Li, Yuanyuan; Wang, Xiaoyun; Li, Xinru; Rong, Li; Shi, Zheng; Bao, Jinku

    2015-12-01

    Glucose transporters (GLUTs) are the main carriers of glucose that facilitate the diffusion of glucose in mammalian cells, especially GLUT1. Notably, GLUT1 is a rate-limiting transporter for glucose uptake, and its overexpression is a common characteristic in most cancers. Thus, the inhibition of GLUT1 by novel small compounds to lower glucose levels for cancer cells has become an emerging strategy. Herein, we employed high-throughput screening approaches to identify potential inhibitors against the sugar-binding site of GLUT1. Firstly, molecular docking screening was launched against the specs products, and three molecules (ZINC19909927, ZINC19908826, and ZINC19815451) were selected as candidate GLUT1 inhibitors for further analysis. Then, taking the initial ligand β-NG as a reference, molecular dynamic (MD) simulations and molecular mechanics/generalized born surface area (MM/GBSA) method were applied to evaluate the binding stability and affinity of the three candidates towards GLUT1. Finally, we found that ZINC19909927 might have the highest affinity to occupy the binding site of GLUT1. Meanwhile, energy decomposition analysis identified several residues located in substrate-binding site that might provide clues for future inhibitor discovery towards GLUT1. Taken together, these results in our study may provide valuable information for identifying new inhibitors targeting GLUT1-mediated glucose transport and metabolism for cancer therapeutics.

  11. Small-molecule inhibitors of cathepsin L incorporating functionalized ring-fused molecular frameworks.

    PubMed

    Song, Jiangli; Jones, Lindsay M; Chavarria, Gustavo E; Charlton-Sevcik, Amanda K; Jantz, Adam; Johansen, Audra; Bayeh, Liela; Soeung, Victoria; Snyder, Lindsey K; Lade, Shawn D; Chaplin, David J; Trawick, Mary Lynn; Pinney, Kevin G

    2013-05-01

    Cathepsin L is a cysteine protease that is upregulated in a variety of malignant tumors and plays a significant role in cancer cell invasion and migration. It is an attractive target for the development of small-molecule inhibitors, which may prove beneficial as treatment agents to limit or arrest cancer metastasis. We have previously identified a structurally diverse series of thiosemicarbazone-based inhibitors that incorporate the benzophenone and thiochromanone molecular scaffolds. Herein we report an important extension of this work designed to explore fused aryl-alkyl ring molecular systems that feature nitrogen atom incorporation (dihydroquinoline-based) and carbon atom exclusivity (tetrahydronaphthalene-based). In addition, analogues that contain oxygen (chromanone-based), sulfur (thiochroman-based), sulfoxide, and sulfone functionalization have been prepared in order to further investigate the structure-activity relationship aspects associated with these compounds and their ability to inhibit cathepsins L and B. From this small-library of 30 compounds, five were found to be strongly inhibitory (IC50 <500 nM) against cathepsin L with the most active compound (7-bromodihydroquinoline thiosemicarbazone 48) demonstrating an IC50=164 nM. All of the compounds evaluated were inactive (IC50 >10,000 nM) as inhibitors of cathepsin B, thus establishing a high degree (>20-fold) of selectivity (cathepsin L vs. cathepsin B) for the most active cathepsin L inhibitors in this series.

  12. Experimental Evaluation of Proposed Small-Molecule Inhibitors of Water Channel Aquaporin-1.

    PubMed

    Esteva-Font, Cristina; Jin, Byung-Ju; Lee, Sujin; Phuan, Puay-Wah; Anderson, Marc O; Verkman, A S

    2016-06-01

    The aquaporin-1 (AQP1) water channel is a potentially important drug target, as AQP1 inhibition is predicted to have therapeutic action in edema, tumor growth, glaucoma, and other conditions. Here, we measured the AQP1 inhibition efficacy of 12 putative small-molecule AQP1 inhibitors reported in six recent studies, and one AQP1 activator. Osmotic water permeability was measured by stopped-flow light scattering in human and rat erythrocytes that natively express AQP1, in hemoglobin-free membrane vesicles from rat and human erythrocytes, and in plasma membrane vesicles isolated from AQP1-transfected Chinese hamster ovary cell cultures. As a positive control, 0.3 mM HgCl2 inhibited AQP1 water permeability by >95%. We found that none of the tested compounds at 50 µM significantly inhibited or increased AQP1 water permeability in these assays. Identification of AQP1 inhibitors remains an important priority. PMID:26993802

  13. Automated approach for the identification of functionally-relevant small molecule inhibitors

    SciTech Connect

    Wilson, D M III

    2000-02-16

    Radiation induces the formation of DNA damages via direct ionization or through the production of reactive oxygen intermediates that chemically modify DNA. Radiation is thought to elicit its cytotoxicity by inducing the formation of lethal DNA damage, including modified bases, baseless sites and strand breaks. To avert the deleterious effects of radiation and chromosomal modifications, cells are equipped with DNA repair systems and cellular responses that function to amend genetic imperfections and to prevent the replication of damaged DNA. The focus of this proposal is to develop a novel, function-based technology for isolating inhibitors of proteins involved in radiation-protection. Such inhibitor molecules represent potential radiosensitizing agents, which could be used to increase the biological effectiveness of a given radiation dose in anti-cancer treatment schemes. This project combines unique laboratory expertise in robotics, computational modeling, combinatorial chemistry, and DNA repair enzymology from the Biology & Biotechnology Research Program and the Chemistry and Material Science Directorate. The screening technique will utilize a simple flow-based filter system operated by robotics. Commercial laboratory instrumentation and automation are available for creating a nearly hands-off system for inhibitor molecule screening. Specifically, a general purpose dispensing instrument (i.e. the Packard Multiprobe II), using opaque, filter-backed microtiter plates, will be combined with on-deck vacuum extraction to generate a rapid screening technology. System integration tools and experience from the LLNL Human Genome Project will be leveraged. This screening capability will be applied to current lab research on proteins involved in the repair of radiation damaged DNA. Inhibitors of proteins involved in cellular resistance to radiation have potential value as co-therapeutics in anti-cancer treatments and would be licensed to pharmaceutical companies for further

  14. Promotion of cell migration by neural cell adhesion molecule (NCAM) is enhanced by PSA in a polysialyltransferase-specific manner.

    PubMed

    Guan, Feng; Wang, Xin; He, Fa

    2015-01-01

    Neural cell adhesion molecule 140 (NCAM-140) is a glycoprotein and always highly polysialylated in cancer. Functions of polysialic acid (PSA) that binds to N-glycan termini on NCAM remain unclear. ldlD-14 cells, a CHO cell mutant deficient in UDP-Gal 4-epimerase, are useful for structural and functional studies of Gal-containing glycoproteins because their abnormal glycosylation can be converted to normal status by exogenous addition of galactose (Gal). We cloned the genes for NCAM-140 and for polysialyltransferases STX and PST (responsible for PSA synthesis) from normal murine mammary gland epithelial (NMuMG) cells and transfected them into ldlD-14 and human breast cancer cells MCF-7. The effect of PSA on NCAM-mediated cell proliferation, motility, migration and adhesion was studied. We found that NCAM-140 significantly promoted cell proliferation, motility and migration, while polysialylation of NCAM-140 catalyzed by STX, but not by PST, enhanced NCAM-mediated cell migration, but not cell proliferation or motility. In addition, PSA catalyzed by different polysialyltransferases affected the adhesion of NCAM to different extracellular matrix (ECM) components. PMID:25885924

  15. In vitro characterization of multivalent adhesion molecule 7-based inhibition of multidrug-resistant bacteria isolated from wounded military personnel.

    PubMed

    Krachler, Anne Marie; Mende, Katrin; Murray, Clinton; Orth, Kim

    2012-07-01

    Treatment of wounded military personnel at military medical centers is often complicated by colonization and infection of wounds with pathogenic bacteria. These include nosocomially transmitted, often multidrug-resistant pathogens such as Acinetobacter baumannii-calcoaceticus complex, Pseudomonas aeruginosa and extended spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae. We analyzed the efficacy of multivalent adhesion molecule (MAM) 7-based anti-adhesion treatment of host cells against aforementioned pathogens in a tissue culture infection model. Herein, we observed that a correlation between two important hallmarks of virulence, attachment and cytotoxicity, could serve as a useful predictor for the success of MAM7-based inhibition against bacterial infections. Initially, we characterized 20 patient isolates (five from each pathogen mentioned above) in terms of genotypic diversity, antimicrobial susceptibility and important hallmarks of pathogenicity (biofilm formation, attachment to and cytotoxicity toward cultured host cells). All isolates displayed a high degree of genotypic diversity, which was also reflected by large strain-to-strain variability in terms of biofilm formation, attachment and cytotoxicity within each group of pathogen. Using non-pathogenic bacteria expressing MAM7 or latex beads coated with recombinant MAM7 for anti-adhesion treatment, we showed a decrease in cytotoxicity, indicating that MAM7 has potential as a prophylactic agent to attenuate infection by multidrug-resistant bacterial pathogens.

  16. Interleukin 3 stimulates proliferation and triggers endothelial-leukocyte adhesion molecule 1 gene activation of human endothelial cells.

    PubMed

    Brizzi, M F; Garbarino, G; Rossi, P R; Pagliardi, G L; Arduino, C; Avanzi, G C; Pegoraro, L

    1993-06-01

    Proliferation and functional activation of endothelial cells within a tissue site of inflammation are regulated by humoral factors released by cells, such as T lymphocytes and monocytes, infiltrating the perivascular space. In the present study we investigated the effects of interleukin 3 (IL-3), an activated T lymphocyte-derived cytokine, on cultured human umbilical vein endothelial cells (HUVEC). Proliferative activity, evaluated both by estimation of the fraction of cells in the S phase and by direct cell count demonstrated that IL-3, at the dose of 25 ng/ml, enhances more than threefold both DNA synthesis and cell proliferation above baseline control conditions. Binding studies with radioiodinated ligand demonstrated that HUVEC constitutively express a smaller number of IL-3 binding sites (approximately 99 binding sites per cell, with an apparent Kd of 149 pM). Accordingly, molecular analysis showed the presence of transcripts for both alpha and beta subunits of the IL-3 receptor. Functional activation of endothelial cells was evaluated by the expression of the endothelial-leukocyte adhesion molecule 1 (ELAM-1) transcript and by leukocyte adhesion. The ELAM-1 gene transcript was clearly detectable 4 h after IL-3 addition and started to decrease after 12 h. Moreover, IL-3-induced ELAM-1 transcription was followed by enhanced adhesion of neutrophils and CD4+ T cells to HUVEC. The findings that IL-3 can stimulate both proliferation and functional activation of endothelial cells suggest that this cytokine can be involved in sustaining the process of chronic inflammation.

  17. Drosophila Furrowed/Selectin is a homophilic cell adhesion molecule stabilizing Frizzled and intercellular interactions during PCP establishment

    PubMed Central

    Chin, Mei-Ling; Mlodzik, Marek

    2013-01-01

    Summary Establishment of planar cell polarity (PCP) in a tissue requires coordination of directional signals from cell to cell. It is thought that this is mediated by the core PCP factors, which include cell adhesion molecules. Here, we demonstrate that furrowed, the Drosophila Selectin, is required for PCP generation. Disruption of PCP in furrowed-deficient flies results from a primary defect in Fz levels and cell adhesion. Furrowed localizes at/near apical junctions, largely co-localizing with Frizzled and Flamingo (Fmi). It physically interacts with and stabilizes Frizzled, and further, it mediates intercellular Frizzled-Van Gogh (Vang)/Strabismus interactions, similarly to Fmi. Furrowed does so through a homophilic cell adhesion role that is distinct from its known carbohydrate-binding function described during vertebrate blood-cell/endothelial cell interactions. Importantly, the carbohydrate function is dispensable for PCP establishment. In vivo studies suggest that Furrowed functions partially redundantly with Fmi, mediating intercellular Frizzled-Vang interactions between neighboring cells. PMID:23973164

  18. New domains of neural cell-adhesion molecule L1 implicated in X-linked hydrocephalus and MASA syndrome

    SciTech Connect

    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 first 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.

  19. Assessment expression of the adhesion molecules, CD134 and CD137, in patients with colorectal cancer by flow cytometry.

    PubMed

    Cepowicz, D; Stasiak-Barmuta, A; Zalewski, B; Piotrowski, Z

    2004-01-01

    The aim of the study was to assess the expression of adhesion molecules, CD134 and CD137, in the peripheral blood in correlation with clinical advancement, the histological grade, the size and type of tumour growth, tissue infiltration, and lymph node and metastases to lymph nodes and liver. The study involved 28 patients with primary colorectal cancer. The expression of both molecules was investigated on the day of the surgery, before the procedure and ten days after the operation by means of flow cytometry. The expression of CD134 was markedly higher, compared to CD137, both on the day of the surgery and ten days after the operation. A significant increase was observed in CD134 expression ten days after the surgery. CD137 expression increased with the higher stage of clinical advancement, but decreased with the enhancement of colon wall infiltration. CD134 showed a similar expression for all the stages of tumour clinical advancement.

  20. Pyrimidine-based tricyclic molecules as potent and orally efficacious inhibitors of wee1 kinase.

    PubMed

    Tong, Yunsong; Torrent, Maricel; Florjancic, Alan S; Bromberg, Kenneth D; Buchanan, Fritz G; Ferguson, Debra C; Johnson, Eric F; Lasko, Loren M; Maag, David; Merta, Philip J; Olson, Amanda M; Osterling, Donald J; Soni, Nirupama; Shoemaker, Alexander R; Penning, Thomas D

    2015-01-01

    Aided by molecular modeling, compounds with a pyrimidine-based tricyclic scaffold were designed and confirmed to inhibit Wee1 kinase. Structure-activity studies identified key pharmacophores at the aminoaryl and halo-benzene regions responsible for binding affinity with sub-nM K i values. The potent inhibitors demonstrated sub-μM activities in both functional and mechanism-based cellular assays and also possessed desirable pharmacokinetic profiles. The lead molecule, 31, showed oral efficacy in potentiating the antiproliferative activity of irinotecan, a cytotoxic agent, in a NCI-H1299 mouse xenograft model.

  1. Identification of a small molecule HIV-1 inhibitor that targets the capsid hexamer.

    PubMed

    Xu, Jimmy P; Branson, Jeffrey D; Lawrence, Rae; Cocklin, Simon

    2016-02-01

    The HIV-1 CA protein is an attractive therapeutic target for the development of new antivirals. An inter-protomer pocket within the hexamer configuration of the CA, which is a binding site for key host dependency factors, is an especially appealing region for small molecule targeting. Using a field-based pharmacophore derived from an inhibitor known to interact with this region, coupled to biochemical and biological assessment, we have identified a new compound that inhibits HIV-1 infection and that targets the assembled CA hexamer. PMID:26747394

  2. Discovery of potent, orally bioavailable small-molecule inhibitors of the human CCR2 receptor.

    PubMed

    Doyon, Julien; Coesemans, Erwin; Boeckx, Staf; Buntinx, Mieke; Hermans, Bart; Van Wauwe, Jean P; Gilissen, Ron A H J; De Groot, Alex H J; Corens, David; Van Lommen, Guy

    2008-04-01

    We recently reported the discovery of a series of 2-thioimidazoles as CCR2 antagonists. The most potent molecules of this series, the 4,5-diesters, were rapidly hydrolyzed to the inactive acids and were found to be metabolically unstable. Herein we describe the synthesis of a number of analogues with heterocyclic bioisosteric replacements of the ester group(s). Small 5-membered heterocyclic substituents at the 4-position gave highly potent CCR2 antagonists. Hydrolysis of the 5-ester is diminished, thus imparting these compounds with sufficient stability and systemic exposure after oral administration to warrant further study of the in vivo pharmacology of these functional CCR2 inhibitors.

  3. Macrophage function in alloxan diabetic mice: expression of adhesion molecules, generation of monokines and oxygen and NO radicals

    PubMed Central

    Ptak, W; Klimek, M; Bryniarski, K; Ptak, M; Majcher, P

    1998-01-01

    The increased incidence of bacterial and mycotic infections in poorly controlled diabetic patients or animals is frequently attributed to impaired activities of professional phagocytes (granulocytes, macrophages) in hypoinsulinaemic milieu. We measured production of monokines (IL-6 and tumour necrosis factor-alpha (TNF-α)), active NO and reactive oxygen intermediates (ROIs), as well as expression of several cell surface adhesion molecules (Mac-1, -2 and -3, intercellular adhesion molecule-1 (ICAM-1) and FcγRII), by thioglycollate medium-induced peritoneal macrophages of normoglycaemic and alloxan diabetic CBA/J mice (blood glucose level in the range 300 or 500 mg/dl). Macrophages of animals with moderate diabetes (300 mg/dl) produced significantly more IL-6 and TNF-α and ROIs than cells of control mice and showed an increased expression of all cell surface molecules, except Mac-3. NO/NO2 production was not affected. Administration of insulin restored enhanced values to normal levels, except for the production of ROIs which remained unusually high. We conclude that two separate mechanisms influence macrophage physiology in diabetes—lack of saturation of insulin receptors on macrophages and an indirect effect due to formation of advanced glycosylation endproducts (AGE) on their surfaces. The latter is possibly responsible for increased generation of ROIs, since it cannot be down-regulated by prolonged insulin treatment. How the increased activity of macrophages of moderately diabetic mice (enhanced production of proinflammatory monokines and oxygen radicals as well as expression of molecules) is related to their ability to kill bacteria is now under investigation. PMID:9764597

  4. Applications of traction force microscopy in measuring adhesion molecule dependent cell contractility

    NASA Astrophysics Data System (ADS)

    Mann, Cynthia Marie

    This work describes the use of polyacrylamide hydrogels as controlled elastic modulus substrates for single cell traction force microscopy studies. The first section describes the use of EDC/NHS chemistry to convalently link microbeads to the hydrogel matrix for the purpose of performing long-term traction force studies (7 days). The final study uses the C2C12 cell line to demonstrate that integrin-mediated adhesion to soft substrates causes different cell behavior than N-cahderin-mediated adhesion to soft substrates. Cells plated on laminin-coated hydrogels exhibited stiffness dependent increases in cell spreading, whereas cells plated on N-cadherin-coated substrates. Similarly, cells plated on laminin-coated substrates exhibited substrate stiffness dependent increases in normalized net contractile moment, however the same cells plated on N-cadherin-coated substrates were unable to deform any but the softest hydrogels.

  5. Semi-microdroplet assay for cell adhesion molecules. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Tawa, Lawrence Shinzo

    1988-01-01

    A new cell-to-cell adhesion assay was devised. Using dissociated embryos of the sea urchin, this procedure involves rotating a 0.100 ml suspension of single cells with 0.100 ml of the solution to be tested in the bulb portion of a transfer pipet with the tip removed. After 1 hour of rotation at 60 rpm at 15 C, the contents of each bulb were transferred into individual wells of a 96 well flat bottom plate. After the plate was incubated for 1 hour at 15 C, black and white photographs were taken with a 35 mm camera attached to an inverted photomicroscope. Examining a proof sheet of the negatives directly allowed a rapid evaluation of suspected cell adhesion promoting factors. A ranking system was used to evaluate all samples. The assay was tested by examining the effect of specific solutions on the aggregation of single cells obtained from dissociated 23 hour embryos.

  6. Polyclonal neural cell adhesion molecule antibody prolongs the effective duration time of botulinum toxin in decreasing muscle strength.

    PubMed

    Guo, Yan; Pan, Lizhen; Liu, Wuchao; Pan, Yougui; Nie, Zhiyu; Jin, Lingjing

    2015-11-01

    This study aimed to investigate if the effective duration time of botulinum toxin A (Btx-A) could be prolonged by polyclonal neural cell adhesion molecule antibody (P-NCAM-Ab). 175 male SD rats were randomly divided into three major groups: control group (n = 25), Btx-A group (n = 25), and P-NCAM-Ab groups. P-NCAM-Ab groups were composed of five sub-groups, with 25 rats each in the dose-response study. Muscle strength of rat lower limbs was determined using a survey system. The expressions of muscle-specific receptor tyrosine kinase (MuSK) and neural cell adhesion molecule (NCAM) were determined by real-time polymerase chain reactions (RT-PCR) and western blotting (WB). The muscle strength was significantly decreased by Btx-A in Btx-A/P-NCAM-Ab groups compared with normal control group. Besides, the muscle strength of P-NCAM-Ab group was significantly decreased compared with the Btx-A group. The recovery time of muscle strength in P-NCAM-Ab group was significantly longer compared with Btx-A group. RT-PCR and WB assay showed that PNCAM-Ab delayed the increase of MuSK and NCAM after Btx-A injection. P-NCAM-Ab prolongs the effective duration time of Btx-A in decreasing muscle strength, which could provide a novel enhancement in clinical application.

  7. Regulation of vascular cell adhesion molecule-1 expression by IL-4 and TNF-alpha in cultured endothelial cells.

    PubMed Central

    Iademarco, M F; Barks, J L; Dean, D C

    1995-01-01

    Interaction between vascular cell adhesion molecule-1 (VCAM-1) on endothelial cells and alpha 4 integrins on leukocytes is thought to mediate the selective recruitment of eosinophils and lymphocytes that occurs in allergic diseases. IL-4 is associated with allergic conditions, and it has been shown to selectively increase expression of VCAM-1 on endothelial cells in vivo, suggesting that it could be responsible for VCAM-1 expression in allergic disease. Using a combination of immunofluorescence, flow cytometry, and Northern analysis, we compared the effect of TNF-alpha and IL-4 on VCAM-1 expression. TNF-alpha is also associated with allergic diseases, and it rapidly increases transcription of the VCAM-1 gene. The effect of IL-4 was relatively modest with prolonged kinetics: VCAM-1 was not detected until 72 h after treatment with IL-4. However, when TNF-alpha and IL-4 were combined, there was a synergistic increase in VCAM-1 expression and a dramatic prolongation of the appearance of VCAM-1 on the cell surface. This synergy results from a combination of transcriptional activation by TNF-alpha and the stabilization of resulting transcripts by IL-4. We propose that IL-4 allows subthreshold concentrations of TNF-alpha (concentrations that would not normally activate expression of adhesion molecules on the endothelium) to selectively increase VCAM-1 expression and to prolong its appearance on the surface of cells in allergic disease. Images PMID:7529260

  8. The adherence of endothelial cells to Dacron induces the expression of the intercellular adhesion molecule (ICAM-1).

    PubMed Central

    Margiotta, M S; Robertson, F S; Greco, R S

    1992-01-01

    The intercellular adhesion molecule (ICAM-1) is a glycoprotein expressed by endothelial cells activated by cytokines. The lymphocyte-function-associated antigen (LFA-1) is an integrin expressed by activated white blood cells. Together, this receptor-ligand pair is responsible, in part, for the localization of neutrophils at sites of inflammation. Using an in vitro model, the authors studied the binding of antibodies against ICAM-1 by human saphenous vein endothelial cells (HSVEC) adherent to Dacron and control cultureware. After adherence to Dacron pretreated with fibronectin, 24% more HSVEC-bound antibody against ICAM-1 compared with HSVEC on controls. In contrast, 90% more HSVEC adherent to Dacron incubated with whole blood bound anti-ICAM-1 antibodies. These cells bound 17.7-fold greater amounts of antibody compared with HSVEC on controls. Pretreating Dacron with plasma resulted in no increase in antibody binding compared with control. Our studies suggest that the cellular components of blood in contact with Dacron create a microenvironment that activates HSVEC and enhances ICAM-1 expression. Induction of this adhesion molecule may play a pivotal role in the migration and localization of leukocytes at the site of the vascular prosthesis. PMID:1359845

  9. Expression of cell adhesion molecule E-cadherin in Xenopus embryos begins at gastrulation and predominates in the ectoderm

    PubMed Central

    1989-01-01

    The expression of the Ca2+-dependent epithelial cell adhesion molecule E-cadherin (also known as uvomorulin and L-CAM) in the early stages of embryonic development of Xenopus laevis was examined. E-Cadherin was identified in the Xenopus A6 epithelial cell line by antibody cross- reactivity and several biochemical characteristics. Four independent mAbs were generated against purified Xenopus E-cadherin. All four mAbs recognized the same polypeptides in A6 cells, adult epithelial tissues, and embryos. These mAbs inhibited the formation of cell contacts between A6 cells and stained the basolateral plasma membranes of A6 cells, hepatocytes, and alveolar epithelial cells. The time of E- cadherin expression in early Xenopus embryos was determined by immunoblotting. Unlike its expression in early mouse embryos, E- cadherin was not present in the eggs or early blastula of Xenopus laevis. These findings indicate that a different Ca2+-dependent cell adhesion molecule, perhaps another member of the cadherin gene family, is responsible for the Ca2+-dependent adhesion between cleavage stage Xenopus blastomeres. Detectable accumulation of E-cadherin started just before gastrulation at stage 9 1/2 and increased rapidly up to the end of gastrulation at stage 15. In stage 15 embryos, specific immunofluorescence staining of E-cadherin was discernible only in ectoderm, but not in mesoderm and endoderm. The ectoderm at this stage consists of two cell layers. The outer cell layer of ectoderm was stained intensely, and staining was localized to the basolateral plasma membrane of these cells. Lower levels of staining were observed in the inner cell layer of ectoderm. The coincidence of E-cadherin expression with the process of gastrulation and its restriction to the ectoderm indicate that it may play a role in the morphogenetic movements of gastrulation and resulting segregation of embryonic germ layers. PMID:2472408

  10. The role of photobiomodulation on gene expression of cell adhesion molecules in diabetic wounded fibroblasts in vitro.

    PubMed

    Ayuk, Sandra M; Abrahamse, Heidi; Houreld, Nicolette N

    2016-08-01

    Cell adhesion molecules (CAMs) are cell surface glycoproteins that facilitate cell-cell contacts and adhesion with the extracellular matrix (ECM). Cellular adhesion is affected by various disease conditions, such as diabetes mellitus (DM) and inflammation. Photobiomodulation (PBM) stimulates biological processes and expression of these cellular molecules. The aim of this experimental work was to demonstrate the role of PBM at 830nm on CAMs in diabetic wounded fibroblast cells. Isolated human skin fibroblast cells were used. Normal (N-) and diabetic wounded (DW-) cells were irradiated with a continuous wave diode laser at 830nm with an energy density of 5J/cm(2). Real time reverse transcriptase polymerase chain reaction (RT-PCR) was used to determine the relative gene expression of 39 CAMs 48h post-irradiation. Normalized expression levels from irradiated cells were calculated relative to non-irradiated control cells according to the 2^(-ΔΔCt) method. Thirty-one genes were significantly regulated in N-cells (28 were genes up-regulated and three genes down-regulated), and 22 genes in DW-cells (five genes were up-regulated and 17 genes down-regulated). PBM induced a stimulatory effect on various CAMs namely cadherins, integrins, selectins and immunoglobulins, and hence may be used as a complementary therapy in advancing treatment of non-healing diabetic ulcers. The regulation of CAMs as well as evaluating the role of PBM on the molecular effects of these genes may expand knowledge and prompt further research into the cellular mechanisms in diabetic wound healing that may lead to valuable clinical outcomes. PMID:27295416

  11. Normalizing the bone marrow microenvironment with p38 inhibitor reduces multiple myeloma cell proliferation and adhesion and suppresses osteoclast formation

    SciTech Connect

    Nguyen, Aaron N.; Stebbins, Elizabeth G.; Henson, Margaret; O'Young, Gilbert; Choi, Sun J.; Quon, Diana; Damm, Debby; Reddy, Mamatha; Ma, Jing Y.; Haghnazari, Edwin; Kapoun, Ann M.; Medicherla, Satyanarayana; Protter, Andy; Schreiner, George F.; Kurihara, Noriyoshi; Anderson, Judy; Roodman, G. David; Navas, Tony A.; Higgins, Linda S. . E-mail: lhiggin3@scius.jnj.com

    2006-06-10

    The multiple myeloma (MM) bone marrow (BM) microenvironment plays a critical role in supporting tumor growth and survival as well as in promoting formation of osteolytic lesions. Recent results suggest that the p38 mitogen-activated protein kinase (MAPK) is an important factor in maintaining this activated environment. In this report, we demonstrate that the p38{alpha} MAPK inhibitor, SCIO-469, suppresses secretion of the tumor-supportive factors IL-6 and VEGF from BM stromal cells (BMSCs) as well as cocultures of BMSCs with MM cells, resulting in reduction in MM cell proliferation. Additionally, we show that SCIO-469 prevents TNF{alpha}-induced adhesion of MM cells to BMSCs through an ICAM-1- and VCAM-1-independent mechanism. Microarray analysis revealed a novel set of TNF{alpha}-induced chemokines in BMSCs that is strongly inhibited by SCIO-469. Furthermore, reintroduction of chemokines CXCL10 and CCL8 to BMSCs overcomes the inhibitory effect of SCIO-469 on TNF{alpha}-induced MM adhesion. Lastly, we show that SCIO-469 inhibits secretion and expression of the osteoclast-activating factors IL-11, RANKL, and MIP-1{alpha} as well as prevents human osteoclast formation in vitro. Collectively, these results suggest that SCIO-469 treatment can suppress factors in the bone marrow microenvironment to inhibit MM cell proliferation and adhesion and also to alleviate osteolytic activation in MM.

  12. Engagement of major histocompatibility complex class I and class II molecules up-regulates intercellular adhesion of human B cells via a CD11/CD18-independent mechanism.

    PubMed

    Alcover, A; Juillard, V; Acuto, O

    1992-02-01

    We have studied the role of major histocompatibility complex (MHC) molecules in the regulation of intercellular adhesion of human B cells. We found that molecules able to bind to MHC class II molecules, such as monoclonal antibodies or staphylococcal enterotoxins, induced rapid and sustained homotypic adhesion of Epstein-Barr virus (EBV)-transformed B cell lines as well as peripheral blood B lymphocytes. Moreover, anti-MHC class I monoclonal antibodies also stimulated intercellular adherence. Adhesion induced upon MHC engagement was faster and stronger than that triggered by phorbol esters. It needed active metabolism, but divalent cations were not required. Monoclonal antibodies directed against LFA-1 (CD11a/CD18) or its ligand ICAM-1 (CD54) did not inhibit MHC class II-induced homotypic adhesion of various EBV-transformed B cell lines, nor of a variant of the B cell line Raji expressing very low LFA-1 surface levels. Moreover, EBV-transformed B cells from a severe lymphocyte adhesion deficiency patient, lacking surface CD11/CD18, also aggregated in response to anti-MHC class I or class II monoclonal antibodies. Together these data indicate that engagement of MHC molecules may transduce signals to B cells resulting in up-regulation of intercellular adhesion, via an LFA-1-independent mechanism. This may play a role in the stabilization of T cell/antigen-presenting cell conjugates at the moment of antigen recognition.

  13. A high throughput screening assay system for the identification of small molecule inhibitors of gsp.

    PubMed

    Bhattacharyya, Nisan; Hu, Xin; Chen, Catherine Z; Mathews Griner, Lesley A; Zheng, Wei; Inglese, James; Austin, Christopher P; Marugan, Juan J; Southall, Noel; Neumann, Susanne; Northup, John K; Ferrer, Marc; Collins, Michael T

    2014-01-01

    Mis-sense mutations in the α-subunit of the G-protein, Gsα, cause fibrous dysplasia of bone/McCune-Albright syndrome. The biochemical outcome of these mutations is constitutively active Gsα and increased levels of cAMP. The aim of this study was to develop an assay system that would allow the identification of small molecule inhibitors specific for the mutant Gsα protein, the so-called gsp oncogene. Commercially available Chinese hamster ovary cells were stably transfected with either wild-type (WT) or mutant Gsα proteins (R201C and R201H). Stable cell lines with equivalent transfected Gsα protein expression that had relatively lower (WT) or higher (R201C and R201H) cAMP levels were generated. These cell lines were used to develop a fluorescence resonance energy transfer (FRET)-based cAMP assay in 1536-well microplate format for high throughput screening of small molecule libraries. A small molecule library of 343,768 compounds was screened to identify modulators of gsp activity. A total of 1,356 compounds with inhibitory activity were initially identified and reconfirmed when tested in concentration dose responses. Six hundred eighty-six molecules were selected for further analysis after removing cytotoxic compounds and those that were active in forskolin-induced WT cells. These molecules were grouped by potency, efficacy, and structural similarities to yield 22 clusters with more than 5 of structurally similar members and 144 singleton molecules. Seven chemotypes of the major clusters were identified for further testing and analyses.

  14. A High Throughput Screening Assay System for the Identification of Small Molecule Inhibitors of gsp

    PubMed Central

    Bhattacharyya, Nisan; Hu, Xin; Chen, Catherine Z.; Mathews Griner, Lesley A.; Zheng, Wei; Inglese, James; Austin, Christopher P.; Marugan, Juan J.; Southall, Noel; Neumann, Susanne; Northup, John K.; Ferrer, Marc; Collins, Michael T.

    2014-01-01

    Mis-sense mutations in the α-subunit of the G-protein, Gsα, cause fibrous dysplasia of bone/McCune-Albright syndrome. The biochemical outcome of these mutations is constitutively active Gsα and increased levels of cAMP. The aim of this study was to develop an assay system that would allow the identification of small molecule inhibitors specific for the mutant Gsα protein, the so-called gsp oncogene. Commercially available Chinese hamster ovary cells were stably transfected with either wild-type (WT) or mutant Gsα proteins (R201C and R201H). Stable cell lines with equivalent transfected Gsα protein expression that had relatively lower (WT) or higher (R201C and R201H) cAMP levels were generated. These cell lines were used to develop a fluorescence resonance energy transfer (FRET)–based cAMP assay in 1536-well microplate format for high throughput screening of small molecule libraries. A small molecule library of 343,768 compounds was screened to identify modulators of gsp activity. A total of 1,356 compounds with inhibitory activity were initially identified and reconfirmed when tested in concentration dose responses. Six hundred eighty-six molecules were selected for further analysis after removing cytotoxic compounds and those that were active in forskolin-induced WT cells. These molecules were grouped by potency, efficacy, and structural similarities to yield 22 clusters with more than 5 of structurally similar members and 144 singleton molecules. Seven chemotypes of the major clusters were identified for further testing and analyses. PMID:24667240

  15. The new InsP3Kinase inhibitor BIP-4 is competitive to InsP3 and blocks proliferation and adhesion of lung cancer cells.

    PubMed

    Schröder, Dominik; Tödter, Klaus; Gonzalez, Beatriz; Franco-Echevarría, Elsa; Rohaly, Gabor; Blecher, Christine; Lin, Hong-Ying; Mayr, Georg W; Windhorst, Sabine

    2015-07-15

    As ectopic expression of the neuronal inositol-1,4,5-trisphosphate-3-kinase A (InsP3Kinase) in tumor cells increases the metastatic potential, InsP3Kinase is an interesting target for tumor therapy. Recently, we have identified a membrane-permeable InsP3Kinase inhibitor (BAMB-4) exhibiting an IC50-value of 20 μM. Here we characterized a new InsP3Kinase inhibitor which shows a 130-fold lower IC50 value (157 ± 57 nM) as compared to BAMB-4. We demonstrate that this nitrophenolic compound, BIP-4, is non-competitive to ATP but competitive to InsP3, thus exhibits a high selectivity for inhibition of InsP3Kinase activity. Docking analysis suggested a putative binding mode of this molecule into the InsP3Kinase active site. Determination of cellular uptake in lung cancer cells (H1299) revealed that 6% of extracellular BIP-4 is internalized by non-endosomal uptake, showing that BIP-4 is not trapped inside endo/lysosomes but is available to inhibit cellular InsP3Kinase activity. Interestingly, we found that BIP-4 mediated inhibition of InsP3Kinase activity in the two lung cancer cell lines H1299 and LN4323 inhibited proliferation and adhesion at IC50 values of 3 μM or 2 μM, respectively. InsP3Kinase inhibition did not alter ATP-induced calcium signals but significantly reduced the level of Ins(1,3,4,5,6)P5. From these data we conclude that the inhibitory effect of BIP-4 on proliferation and adhesion of lung cancer cells does not result from alterations of calcium but from alterations of inositol phosphate signals. In summary, we reveal that inhibition of cellular InsP3Kinase by BIP-4 impairs proliferation and adhesion and therefore BIP-4 might be a promising compound to reduce the metastatic potential of lung carcinoma cells.

  16. Serum leptin levels in relation to circulating cytokines, chemokines, adhesion molecules and angiogenic factors in normal pregnancy and preeclampsia

    PubMed Central

    2011-01-01

    Objective In this study, we determined circulating levels of C-reactive protein, several cytokines, chemokines, adhesion molecules and angiogenic factors along with those of leptin in healthy non-pregnant and pregnant women and preeclamptic patients, and investigated whether serum leptin levels were related to the clinical characteristics and measured laboratory parameters of the study participants. Methods Sixty preeclamptic patients, 60 healthy pregnant women and 59 healthy non-pregnant women were involved in this case-control study. Levels of leptin and transforming growth factor (TGF)-beta1 in maternal sera were assessed by ELISA. Serum levels of interleukin (IL)-1beta, IL-1 receptor antagonist (IL-1ra), IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p40, IL-12p70, IL-18, interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, interferon-gamma-inducible protein (IP)-10, monocyte chemotactic protein (MCP)-1, intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 were determined by multiplex suspension array. Serum C-reactive protein (CRP) concentrations were measured by an autoanalyzer. Serum total soluble fms-like tyrosine kinase-1 (sFlt-1) and biologically active placental growth factor (PlGF) levels were determined by electrochemiluminescence immunoassay. For statistical analyses, non-parametric methods were applied. Results There were significant differences in most of the measured laboratory parameters among the three study groups except for serum IL-1beta and TGF-beta1 levels. Serum leptin levels were significantly higher in preeclamptic patients and healthy pregnant women than in healthy non-pregnant women. Additionally, preeclamptic patients had significantly higher leptin levels as compared to healthy pregnant women. Serum leptin levels were independently associated with BMI in healthy non-pregnant women. In healthy pregnant women, both BMI and serum CRP concentrations showed significant positive linear association with leptin

  17. Mode of action of DNA-competitive small molecule inhibitors of tyrosyl DNA phosphodiesterase 2.

    PubMed

    Hornyak, Peter; Askwith, Trevor; Walker, Sarah; Komulainen, Emilia; Paradowski, Michael; Pennicott, Lewis E; Bartlett, Edward J; Brissett, Nigel C; Raoof, Ali; Watson, Mandy; Jordan, Allan M; Ogilvie, Donald J; Ward, Simon E; Atack, John R; Pearl, Laurence H; Caldecott, Keith W; Oliver, Antony W

    2016-07-01

    Tyrosyl-DNA phosphodiesterase 2 (TDP2) is a 5'-tyrosyl DNA phosphodiesterase important for the repair of DNA adducts generated by non-productive (abortive) activity of topoisomerase II (TOP2). TDP2 facilitates therapeutic resistance to topoisomerase poisons, which are widely used in the treatment of a range of cancer types. Consequently, TDP2 is an interesting target for the development of small molecule inhibitors that could restore sensitivity to topoisomerase-directed therapies. Previous studies identified a class of deazaflavin-based molecules that showed inhibitory activity against TDP2 at therapeutically useful concentrations, but their mode of action was uncertain. We have confirmed that the deazaflavin series inhibits TDP2 enzyme activity in a fluorescence-based assay, suitable for high-throughput screen (HTS)-screening. We have gone on to determine crystal structures of these compounds bound to a 'humanized' form of murine TDP2. The structures reveal their novel mode of action as competitive ligands for the binding site of an incoming DNA substrate, and point the way to generating novel and potent inhibitors of TDP2.

  18. Mode of action of DNA-competitive small molecule inhibitors of tyrosyl DNA phosphodiesterase 2

    PubMed Central

    Hornyak, Peter; Askwith, Trevor; Walker, Sarah; Komulainen, Emilia; Paradowski, Michael; Pennicott, Lewis E.; Bartlett, Edward J.; Brissett, Nigel C.; Raoof, Ali; Watson, Mandy; Jordan, Allan M.; Ogilvie, Donald J.; Ward, Simon E.; Atack, John R.; Pearl, Laurence H.; Caldecott, Keith W.; Oliver, Antony W.

    2016-01-01

    Tyrosyl-DNA phosphodiesterase 2 (TDP2) is a 5′-tyrosyl DNA phosphodiesterase important for the repair of DNA adducts generated by non-productive (abortive) activity of topoisomerase II (TOP2). TDP2 facilitates therapeutic resistance to topoisomerase poisons, which are widely used in the treatment of a range of cancer types. Consequently, TDP2 is an interesting target for the development of small molecule inhibitors that could restore sensitivity to topoisomerase-directed therapies. Previous studies identified a class of deazaflavin-based molecules that showed inhibitory activity against TDP2 at therapeutically useful concentrations, but their mode of action was uncertain. We have confirmed that the deazaflavin series inhibits TDP2 enzyme activity in a fluorescence-based assay, suitable for high-throughput screen (HTS)-screening. We have gone on to determine crystal structures of these compounds bound to a ‘humanized’ form of murine TDP2. The structures reveal their novel mode of action as competitive ligands for the binding site of an incoming DNA substrate, and point the way to generating novel and potent inhibitors of TDP2. PMID:27099339

  19. Small-molecule inhibitors of protein-protein interactions: progressing towards the reality

    PubMed Central

    Arkin, Michelle R.; Tang, Yinyan; Wells, James A.

    2014-01-01

    Summary The past twenty years have seen many advances in our understanding of protein-protein interactions (PPI) and how to target them with small-molecule therapeutics. In 2004, we reviewed some early successes; since then, potent inhibitors have been developed for diverse protein complexes, and compounds are now in clinical trials for six targets. Surprisingly, many of these PPI clinical candidates have efficiency metrics typical of ‘lead-like’ or ‘drug-like’ molecules and are orally available. Successful discovery efforts have integrated multiple disciplines and make use of all the modern tools of target-based discovery - structure, computation, screening, and biomarkers. PPI become progressively more challenging as the interfaces become more complex, i.e., as binding epitopes are displayed on primary, secondary, or tertiary structures. Here, we review the last ten years of progress, focusing on the properties of PPI inhibitors that have advanced to clinical trials and prospects for the future of PPI drug discovery. PMID:25237857

  20. Towards Development of Small Molecule Lipid II Inhibitors as Novel Antibiotics

    PubMed Central

    Chauhan, Jamal; Cardinale, Steven; Fang, Lei; Huang, Jing; Kwasny, Steven M.; Pennington, M. Ross; Basi, Kelly; diTargiani, Robert; Capacio, Benedict R.; MacKerell, Alexander D.; Opperman, Timothy J.; Fletcher, Steven; de Leeuw, Erik P. H.

    2016-01-01

    Recently we described a novel di-benzene-pyrylium-indolene (BAS00127538) inhibitor of Lipid II. BAS00127538 (1-Methyl-2,4-diphenyl-6-((1E,3E)-3-(1,3,3-trimethylindolin-2-ylidene)prop-1-en-1-yl)pyryl-1-ium) tetrafluoroborate is the first small molecule Lipid II inhibitor and is structurally distinct from natural agents that bind Lipid II, such as vancomycin. Here, we describe the synthesis and biological evaluation of 50 new analogs of BAS00127538 designed to explore the structure-activity relationships of the scaffold. The results of this study indicate an activity map of the scaffold, identifying regions that are critical to cytotoxicity, Lipid II binding and range of anti-bacterial action. One compound, 6jc48-1, showed significantly enhanced drug-like properties compared to BAS00127538. 6jc48-1 has reduced cytotoxicity, while retaining specific Lipid II binding and activity against Enterococcus spp. in vitro and in vivo. Further, this compound showed a markedly improved pharmacokinetic profile with a half-life of over 13 hours upon intravenous and oral administration and was stable in plasma. These results suggest that scaffolds like that of 6jc48-1 can be developed into small molecule antibiotic drugs that target Lipid II. PMID:27776124

  1. Small-Molecule Inhibitors of GSK-3: Structural Insights and Their Application to Alzheimer's Disease Models

    PubMed Central

    Kramer, Thomas; Schmidt, Boris; Lo Monte, Fabio

    2012-01-01

    The world health organization (WHO) estimated that 18 million people are struck by Alzheimer's disease (AD). The USA, France, Germany, and other countries launched major programmes targeting the identification of risk factors, the improvement of caretaking, and fundamental research aiming to postpone the onset of AD. The glycogen synthase kinase 3 (GSK-3) is implicated in multiple cellular processes and has been linked to the pathogenesis of several diseases including diabetes mellitus, cancer, and AD. Inhibition of GSK-3 leads to neuroprotective effects, decreased β-amyloid production, and a reduction in tau hyperphosphorylation, which are all associated with AD. Various classes of small molecule GSK-3 inhibitors have been published in patents and original publications. Herein, we present a comprehensive summary of small molecules reported to interact with GSK-3. We illustrate the interactions of the inhibitors with the active site. Furthermore, we refer to the biological characterisation in terms of activity and selectivity for GSK-3, elucidate in vivo studies and pre-/clinical trials. PMID:22888461

  2. Small-molecule inhibitors of lethal factor protease activity protect against anthrax infection.

    PubMed

    Moayeri, Mahtab; Crown, Devorah; Jiao, Guan-Sheng; Kim, Seongjin; Johnson, Alan; Leysath, Clinton; Leppla, Stephen H

    2013-09-01

    Bacillus anthracis, the causative agent of anthrax, manifests its pathogenesis through the action of two secreted toxins. The bipartite lethal and edema toxins, a combination of lethal factor or edema factor with the protein protective antigen, are important virulence factors for this bacterium. We previously developed small-molecule inhibitors of lethal factor proteolytic activity (LFIs) and demonstrated their in vivo efficacy in a rat lethal toxin challenge model. In this work, we show that these LFIs protect against lethality caused by anthrax infection in mice when combined with subprotective doses of either antibiotics or neutralizing monoclonal antibodies that target edema factor. Significantly, these inhibitors provided protection against lethal infection when administered as a monotherapy. As little as two doses (10 mg/kg) administered at 2 h and 8 h after spore infection was sufficient to provide a significant survival benefit in infected mice. Administration of LFIs early in the infection was found to inhibit dissemination of vegetative bacteria to the organs in the first 32 h following infection. In addition, neutralizing antibodies against edema factor also inhibited bacterial dissemination with similar efficacy. Together, our findings confirm the important roles that both anthrax toxins play in establishing anthrax infection and demonstrate the potential for small-molecule therapeutics targeting these proteins.

  3. A molecular-beacon-based screen for small molecule inhibitors of miRNA maturation.

    PubMed

    Bose, Debojit; Jayaraj, Gopal Gunanathan; Kumar, Santosh; Maiti, Souvik

    2013-05-17

    miRNAs are small non-coding RNAs that regulate about 60% of mammalian genes by modulating their transcript levels. Network scale studies of miRNA-mediated regulatory circuits demonstrate the central importance of this class of small RNA in the maintenance of biological robustness. More recently, several reports have described the deregulation of numerous miRNA to be causally associated with many diseases, including cancer. These studies have highlighted the potential for development of therapeutic modalities against miRNA. Previous screening protocols, for small molecules targeting miRNA function, are either costly or technically too complex to be applied in a high-throughput manner in standard chemical laboratories. We describe a simple in vitro screening method using a DNA-based molecular beacon that overcomes the limitations associated with earlier screens. We used this method to identify inhibitors of miR-27a function from a library of 14 aminoglycosides as a pilot study. Inhibitory molecules identified were further scrutinized to identify the validity of screen. With this proof of concept we illustrate the utility of a scalable molecular-beacon-based screening strategy for miRNA inhibitors.

  4. Identification and characterization of potent small molecule inhibitor of hemorrhagic fever New World arenaviruses.

    PubMed

    Bolken, Tove C; Laquerre, Sylvie; Zhang, Yuanming; Bailey, Thomas R; Pevear, Daniel C; Kickner, Shirley S; Sperzel, Lindsey E; Jones, Kevin F; Warren, Travis K; Amanda Lund, S; Kirkwood-Watts, Dana L; King, David S; Shurtleff, Amy C; Guttieri, Mary C; Deng, Yijun; Bleam, Maureen; Hruby, Dennis E

    2006-02-01

    Category A arenaviruses as defined by the National Institute of Allergy and Infectious Diseases (NIAID) are human pathogens that could be weaponized by bioterrorists. Many of these deadly viruses require biosafety level-4 (BSL-4) containment for all laboratory work, which limits traditional laboratory high-throughput screening (HTS) for identification of small molecule inhibitors. For those reasons, a related BSL-2 New World arenavirus, Tacaribe virus, 67-78% identical to Junín virus at the amino acid level, was used in a HTS campaign where approximately 400,000 small molecule compounds were screened in a Tacaribe virus-induced cytopathic effect (CPE) assay. Compounds identified in this screen showed antiviral activity and specificity against not only Tacaribe virus, but also the Category A New World arenaviruses (Junín, Machupo, and Guanarito). Drug resistant variants were isolated, suggesting that these compounds act through inhibition of a viral protein, the viral glycoprotein (GP2), and not through cellular toxicity mechanisms. A lead compound, ST-294, has been chosen for drug development. This potent and selective compound, with good bioavailability, demonstrated protective anti-viral efficacy in a Tacaribe mouse challenge model. This series of compounds represent a new class of inhibitors that may warrant further development for potential inclusion in a strategic stockpile.

  5. Expression of the immunoglobulin superfamily cell adhesion molecules in the developing spinal cord and dorsal root ganglion.

    PubMed

    Gu, Zirong; Imai, Fumiyasu; Kim, In Jung; Fujita, Hiroko; Katayama, Kei ichi; Mori, Kensaku; Yoshihara, Yoshihiro; Yoshida, Yutaka

    2015-01-01

    Cell adhesion molecules belonging to the immunoglobulin superfamily (IgSF) control synaptic specificity through hetero- or homophilic interactions in different regions of the nervous system. In the developing spinal cord, monosynaptic connections of exquisite specificity form between proprioceptive sensory neurons and motor neurons, however, it is not known whether IgSF molecules participate in regulating this process. To determine whether IgSF molecules influence the establishment of synaptic specificity in sensory-motor circuits, we examined the expression of 157 IgSF genes in the developing dorsal root ganglion (DRG) and spinal cord by in situ hybridization assays. We find that many IgSF genes are expressed by sensory and motor neurons in the mouse developing DRG and spinal cord. For instance, Alcam, Mcam, and Ocam are expressed by a subset of motor neurons in the ventral spinal cord. Further analyses show that Ocam is expressed by obturator but not quadriceps motor neurons, suggesting that Ocam may regulate sensory-motor specificity in these sensory-motor reflex arcs. Electrophysiological analysis shows no obvious defects in synaptic specificity of monosynaptic sensory-motor connections involving obturator and quadriceps motor neurons in Ocam mutant mice. Since a subset of Ocam+ motor neurons also express Alcam, Alcam or other functionally redundant IgSF molecules may compensate for Ocam in controlling sensory-motor specificity. Taken together, these results reveal that IgSF molecules are broadly expressed by sensory and motor neurons during development, and that Ocam and other IgSF molecules may have redundant functions in controlling the specificity of sensory-motor circuits.

  6. High throughput screen identifies small molecule inhibitors specific for Mycobacterium tuberculosis phosphoserine phosphatase.

    PubMed

    Arora, Garima; Tiwari, Prabhakar; Mandal, Rahul Shubhra; Gupta, Arpit; Sharma, Deepak; Saha, Sudipto; Singh, Ramandeep

    2014-09-01

    The emergence of drug-resistant strains of Mycobacterium tuberculosis makes identification and validation of newer drug targets a global priority. Phosphoserine phosphatase (PSP), a key essential metabolic enzyme involved in conversion of O-phospho-l-serine to l-serine, was characterized in this study. The M. tuberculosis genome harbors all enzymes involved in l-serine biosynthesis including two PSP homologs: Rv0505c (SerB1) and Rv3042c (SerB2). In the present study, we have biochemically characterized SerB2 enzyme and developed malachite green-based high throughput assay system to identify SerB2 inhibitors. We have identified 10 compounds that were structurally different from known PSP inhibitors, and few of these scaffolds were highly specific in their ability to inhibit SerB2 enzyme, were noncytotoxic against mammalian cell lines, and inhibited M. tuberculosis growth in vitro. Surface plasmon resonance experiments demonstrated the relative binding for these inhibitors. The two best hits identified in our screen, clorobiocin and rosaniline, were bactericidal in activity and killed intracellular bacteria in a dose-dependent manner. We have also identified amino acid residues critical for these SerB2-small molecule interactions. This is the first study where we validate that M. tuberculosis SerB2 is a druggable and suitable target to pursue for further high throughput assay system screening. PMID:25037224

  7. Identification of Small-Molecule Inhibitors against Meso-2, 6-Diaminopimelate Dehydrogenase from Porphyromonas gingivalis

    PubMed Central

    Stone, Victoria N.; Parikh, Hardik I.; El-rami, Fadi; Ge, Xiuchun; Chen, Weihau; Zhang, Yan; Kellogg, Glen E.; Xu, Ping

    2015-01-01

    Species-specific antimicrobial therapy has the potential to combat the increasing threat of antibiotic resistance and alteration of the human microbiome. We therefore set out to demonstrate the beginning of a pathogen-selective drug discovery method using the periodontal pathogen Porphyromonas gingivalis as a model. Through our knowledge of metabolic networks and essential genes we identified a “druggable” essential target, meso-diaminopimelate dehydrogenase, which is found in a limited number of species. We adopted a high-throughput virtual screen method on the ZINC chemical library to select a group of potential small-molecule inhibitors. Meso-diaminopimelate dehydrogenase from P. gingivalis was first expressed and purified in Escherichia coli then characterized for enzymatic inhibitor screening studies. Several inhibitors with similar structural scaffolds containing a sulfonamide core and aromatic substituents showed dose-dependent inhibition. These compounds were further assayed showing reasonable whole-cell activity and the inhibition mechanism was determined. We conclude that the establishment of this target and screening strategy provides a model for the future development of new antimicrobials. PMID:26544875

  8. Targeting Cyclin-Dependent Kinases in Human Cancers: From Small Molecules to Peptide Inhibitors

    PubMed Central

    Peyressatre, Marion; Prével, Camille; Pellerano, Morgan; Morris, May C.

    2015-01-01

    Cyclin-dependent kinases (CDK/Cyclins) form a family of heterodimeric kinases that play central roles in regulation of cell cycle progression, transcription and other major biological processes including neuronal differentiation and metabolism. Constitutive or deregulated hyperactivity of these kinases due to amplification, overexpression or mutation of cyclins or CDK, contributes to proliferation of cancer cells, and aberrant activity of these kinases has been reported in a wide variety of human cancers. These kinases therefore constitute biomarkers of proliferation and attractive pharmacological targets for development of anticancer therapeutics. The structural features of several of these kinases have been elucidated and their molecular mechanisms of regulation characterized in depth, providing clues for development of drugs and inhibitors to disrupt their function. However, like most other kinases, they constitute a challenging class of therapeutic targets due to their highly conserved structural features and ATP-binding pocket. Notwithstanding, several classes of inhibitors have been discovered from natural sources, and small molecule derivatives have been synthesized through rational, structure-guided approaches or identified in high throughput screens. The larger part of these inhibitors target ATP pockets, but a growing number of peptides targeting protein/protein interfaces are being proposed, and a small number of compounds targeting allosteric sites have been reported. PMID:25625291

  9. Identification of an Allosteric Small Molecule Inhibitor Selective for Inducible Form of Heat Shock Protein 70

    PubMed Central

    Howe, Matthew K.; Bodoor, Khaldon; Carlson, David A.; Hughes, Philip F.; Alwarawrah, Yazan; Loiselle, David R.; Jaeger, Alex M.; Darr, David B.; Jordan, Jamie L.; Hunter, Lucas M.; Molzberger, Eileen T.; Gobillot, Theodore A.; Thiele, Dennis J.; Brodsky, Jeffrey L.; Spector, Neil L.; Haystead, Timothy A. J.

    2014-01-01

    Summary Inducible Hsp70 (Hsp70i) is overexpressed in a wide spectrum of human tumors and its expression correlates with metastasis, poor outcomes, and resistance to chemotherapy in patients. Identification of small molecule inhibitors selective for Hsp70i could provide new therapeutic tools for cancer treatment. In this work, we used fluorescence-linked enzyme chemoproteomic strategy (FLECS) to identify HS-72, an allosteric inhibitor selective for Hsp70i. HS-72 displays the hallmarks of Hsp70 inhibition in cells, promoting substrate protein degradation and growth inhibition. Importantly, HS-72 is selective for Hsp70i over the closely related constitutively active Hsc70. Studies with purified protein show HS-72 acts as an allosteric inhibitor, reducing ATP affinity. In vivo HS-72 is well-tolerated, showing bioavailability and efficacy, inhibiting tumor growth and promoting survival in a HER2+ model of breast cancer. The HS-72 scaffold is amenable to resynthesis and iteration, suggesting an ideal starting point for a new generation of anticancer therapeutics targeting Hsp70i. PMID:25500222

  10. Structure-Based Drug Design of Small Molecule Peptide Deformylase Inhibitors to Treat Cancer.

    PubMed

    Gao, Jian; Wang, Tao; Qiu, Shengzhi; Zhu, Yasheng; Liang, Li; Zheng, Youguang

    2016-01-01

    Human peptide deformylase (HsPDF) is an important target for anticancer drug discovery. In view of the limited HsPDF, inhibitors were reported, and high-throughput virtual screening (HTVS) studies based on HsPDF for developing new PDF inhibitors remain to be reported. We reported here on diverse small molecule inhibitors with excellent anticancer activities designed based on HTVS and molecular docking studies using the crystal structure of HsPDF. The compound M7594_0037 exhibited potent anticancer activities against HeLa, A549 and MCF-7 cell lines with IC50s of 35.26, 29.63 and 24.63 μM, respectively. Molecular docking studies suggested that M7594_0037 and its three derivatives could interact with HsPDF by several conserved hydrogen bonds. Moreover, the pharmacokinetic and toxicity properties of M7594_0037 and its derivatives were predicted using the OSIRIS property explorer. Thus, M7594_0037 and its derivatives might represent a promising scaffold for the further development of novel anticancer drugs. PMID:27023495

  11. Pharmacology of novel small-molecule tubulin inhibitors in glioblastoma cells with enhanced EGFR signalling.

    PubMed

    Phoa, Athena F; Browne, Stephen; Gurgis, Fadi M S; Åkerfeldt, Mia C; Döbber, Alexander; Renn, Christian; Peifer, Christian; Stringer, Brett W; Day, Bryan W; Wong, Chin; Chircop, Megan; Johns, Terrance G; Kassiou, Michael; Munoz, Lenka

    2015-12-15

    We recently reported that CMPD1, originally developed as an inhibitor of MK2 activation, primarily inhibits tubulin polymerisation and induces apoptosis in glioblastoma cells. In the present study we provide detailed pharmacological investigation of CMPD1 analogues with improved molecular properties. We determined their anti-cancer efficacy in glioblastoma cells with enhanced EGFR signalling, as deregulated EGFR often leads to chemoresistance. Eight analogues of CMPD1 with varying lipophilicity and basicity were synthesised and tested for efficacy in the cell viability assay using established glioblastoma cell lines and patient-derived primary glioblastoma cells. The mechanism of action for the most potent analogue 15 was determined using MK2 activation and tubulin polymerisation assays, together with the immunofluorescence analysis of the mitotic spindle formation. Apoptosis was analysed by Annexin V staining, immunoblotting analysis of bcl-2 proteins and PARP cleavage. The apoptotic activity of CMPD1 and analogue 15 was comparable across glioblastoma cell lines regardless of the EGFR status. Primary glioblastoma cells of the classical subtype that are characterized by enhanced EGFR activity were most sensitive to the treatment with CMPD1 and 15. In summary, we present mechanism of action for a novel small molecule tubulin inhibitor, compound 15 that inhibits tubulin polymerisation and mitotic spindle formation, induces degradation of anti-apoptotic bcl-2 proteins and leads to apoptosis of glioblastoma cells. We also demonstrate that the enhanced EGFR activity does not decrease the efficacy of tubulin inhibitors developed in this study.

  12. Identification of alsterpaullone as a novel small molecule inhibitor to target group 3 medulloblastoma

    PubMed Central

    Faria, Claudia C.; Agnihotri, Sameer; Mack, Stephen C.; Golbourn, Brian J.; Diaz, Roberto J.; Olsen, Samantha; Bryant, Melissa; Bebenek, Matthew; Wang, Xin; Bertrand, Kelsey C.; Kushida, Michelle; Head, Renee; Clark, Ian; Dirks, Peter; Smith, Christian A.; Taylor, Michael D.; Rutka, James T.

    2015-01-01

    Advances in the molecular biology of medulloblastoma revealed four genetically and clinically distinct subgroups. Group 3 medulloblastomas are characterized by frequent amplifications of the oncogene MYC, a high incidence of metastasis, and poor prognosis despite aggressive therapy. We investigated several potential small molecule inhibitors to target Group 3 medulloblastomas based on gene expression data using an in silico drug screen. The Connectivity Map (C-MAP) analysis identified piperlongumine as the top candidate drug for non-WNT medulloblastomas and the cyclin-dependent kinase (CDK) inhibitor alsterpaullone as the compound predicted to have specific antitumor activity against Group 3 medulloblastomas. To validate our findings we used these inhibitors against established Group 3 medulloblastoma cell lines. The C-MAP predicted drugs reduced cell proliferation in vitro and increased survival in Group 3 medulloblastoma xenografts. Alsterpaullone had the highest efficacy in Group 3 medulloblastoma cells. Genomic profiling of Group 3 medulloblastoma cells treated with alsterpaullone confirmed inhibition of cell cycle-related genes, and down-regulation of MYC. Our results demonstrate the preclinical efficacy of using a targeted therapy approach for Group 3 medulloblastomas. Specifically, we provide rationale for advancing alsterpaullone as a targeted therapy in Group 3 medulloblastoma. PMID:26061748

  13. Activated peripheral lymphocytes with increased expression of cell adhesion molecules and cytotoxic markers are associated with dengue fever disease.

    PubMed

    Azeredo, Elzinandes L; Zagne, Sonia M O; Alvarenga, Allan R; Nogueira, Rita M R; Kubelka, Claire F; de Oliveira-Pinto, Luzia M

    2006-06-01

    The immune mechanisms involved in dengue fever and dengue hemorrhagic/dengue shock syndrome are not well understood. The ex vivo activation status of immune cells during the dengue disease in patients was examined. CD4 and CD8 T cells were reduced during the acute phase. Interestingly, CD8 T cells co-expressing activation marker HLA-DR, Q, P, and cytolytic granule protein-Tia-1 were significantly higher in dengue patients than in controls. Detection of adhesion molecules indicated that in dengue patients the majority of T cells (CD4 and CD8) express the activation/memory phenotype, characterized as CD44HIGH and lack the expression of the naïve cell marker, CD62L LOW. Also, the levels of T cells co-expressing ICAM-1 (CD54), VLA-4, and LFA-1 (CD11a) were significantly increased. CD8 T lymphocytes expressed predominantly low levels of anti-apoptotic molecule Bcl-2 in the acute phase, possibly leading to the exhibition of a phenotype of activated/effector cells. Circulating levels of IL-18, TGF-b1 and sICAM-1 were significantly elevated in dengue patients. Early activation events occur during acute dengue infection which might contribute to viral clearance. Differences in expression of adhesion molecules among CD4 and CD8 T cells might underlie the selective extravasation of these subsets from blood circulation into lymphoid organs and/or tissues. In addition, activated CD8 T cells would be more susceptible to apoptosis as shown by the alteration in Bcl-2 expression. Cytokines such as IL-18, TGF-b1, and sICAM-1 may be contributing by either stimulating or suppressing the adaptative immune response, during dengue infection, thereby perhaps establishing a relationship with disease severity.

  14. Apoptosis is associated with reduced expression of complement regulatory molecules, adhesion molecules and other receptors on polymorphonuclear leucocytes: functional relevance and role in inflammation.

    PubMed Central

    Jones, J; Morgan, B P

    1995-01-01

    Human polymorphonuclear leucocytes (PMN) express proteins that protect them from damage by homologous complement. Protection may be particularly important when these cells migrate to inflammatory sites where complement activation is taking place. Resolution of inflammation involves removal of these PMN. The major mechanism of removal is likely to involve PMN apoptosis followed by recognition and engulfment by macrophages. However, little attention has been paid to the possible relevance of apoptosis to PMN susceptibility to immune effectors. Here we describe a reduction in cell surface expression of two complement regulatory proteins, CD59, an inhibitor of the membrane attack complex and CD55 (decay accelerating factor), an inhibitor of the C3/C5 convertase, on a subpopulation of PMN aged in culture. Loss of these proteins, both attached to the membrane by glycosyl phosphatidylinositol (GPI) anchors, correlated closely with the appearance of apoptotic morphology. We also observed a marked reduction in expression of the GPI-anchored molecule CD16 on apoptotic PMN. Reduced expression of membrane proteins was not confined to those anchored through GPI--several transmembrane molecules including CD11a CD11b and CD18 were also reduced on apoptotic PMN, whilst other were little changed (CD35, CD46). The precipitous fall in CD16 surface expression on PMN was not specific for apoptosis--in vitro incubation of PMN with lipopolysaccharide-inhibited apoptosis but caused a reduction in CD16 expression to 'apoptotic' levels. Images Figure 2 PMID:8567034

  15. Development of A Cell-Based Assay to Identify Small Molecule Inhibitors of FGF23 Signaling.

    PubMed

    Diener, Susanne; Schorpp, Kenji; Strom, Tim-Matthias; Hadian, Kamyar; Lorenz-Depiereux, Bettina

    2015-10-01

    Fibroblast growth factor 23 (FGF23) is a bone-derived endocrine key regulator of phosphate homeostasis. It inhibits renal tubular phosphate reabsorption by activating receptor complexes composed of FGF receptor 1c (FGFR1c) and the co-receptor Klotho. As a major signaling pathway mitogen-activated protein kinase (MAPK) pathway is employed. In this study, we established an FGF23-inducible cell model by stably expressing human Klotho in HEK293 cells (HEK293-KL cells) containing endogenous FGF receptors. To identify novel small molecule compounds that modulate FGF23/FGFR1c/Klotho signaling, we developed and optimized a cell-based assay that is suited for high-throughput screening. The assay monitors the phosphorylation of endogenous extracellular signal-regulated kinase 1 and 2 in cellular lysates of HEK293-KL cells after induction with FGF23. This cell-based assay was highly robust (Z' factor >0.5) and the induction of the system is strictly dependent on the presence of FGF23. The inhibitor response curves generated using two known MAPK pathway inhibitors correlate well with data obtained by another assay format. This assay was further used to identify small molecule modulators of the FGF23 signaling cascade by screening the 1,280 food and drug administration-approved small molecule library of Prestwick Chemical. The primary hit rate was 2% and false positives were efficiently identified by retesting the hits in primary and secondary validation screening assays and in western blot analysis. Intriguingly, by using a basic FGF (bFGF)/FGFR counterscreening approach, one validated hit compound retained specificity toward FGF23 signaling, while bFGF signaling was not affected. Since increased plasma concentrations of FGF23 are the main cause of many hypophosphatemic disorders, a modulation of its effect could be a potential novel strategy for therapeutic intervention. Moreover, this strategy may be valuable for other disorders affecting phosphate homeostasis. PMID:26461432

  16. Diagnostic use of cytokeratins, CD34, and neuronal cell adhesion molecule staining in focal nodular hyperplasia and hepatic adenoma.

    PubMed

    Ahmad, Imran; Iyer, Anita; Marginean, Celia E; Yeh, Matthew M; Ferrell, Linda; Qin, Lihui; Bifulco, Carlo B; Jain, Dhanpat

    2009-05-01

    Cytokeratins 7 and 19 and neuronal cell adhesion molecule (CD56) are differentially expressed in the hepatocytes and biliary epithelium. CD34 is an endothelial marker that is expressed in hepatic sinusoids in conditions associated with altered vascular flow and neoplasms. Distinct staining patterns using these markers have been shown in resected specimens of focal nodular hyperplasia, telangiectatic focal nodular hyperplasia, and hepatic adenoma. The purpose of this study was to examine the diagnostic use of these markers in needle biopsies. Needle biopsies from focal nodular hyperplasia (n = 21), telangiectatic focal nodular hyperplasia (n = 2), and hepatic adenoma (n = 14) were included in the study. These cases represent typical examples of each entity that have been diagnosed on the basis of clinical, imaging, and histologic features. Corresponding resection specimens available in 9 cases were also included in the study for comparison. Immunohistochemical analysis was performed on 4-mum-thick formalin-fixed and paraffin-embedded sections using antibodies against cytokeratin 7, cytokeratin 19, neuronal cell adhesion molecule, and CD34. The staining patterns and intensity for each marker were analyzed in a blinded fashion, and the patterns were recorded as focal nodular hyperplasia-like, hepatic adenoma-like, or indeterminate for each case. Presence of normal tissue was also recorded in each case. The hepatic adenoma-like pattern is characterized by strong cytokeratin 7 positivity in hepatocytes in patches with a gradual decrease in the staining intensity as the cells differentiate toward mature hepatocytes. Hepatic adenomas lack bile ducts and ductules as highlighted by cytokeratin 7, cytokeratin 19, and neuronal cell adhesion molecule stains. The focal nodular hyperplasia-like pattern is characterized by milder and focal cytokeratin 7 staining of hepatocytes. Cytokeratin 7, cytokeratin 19, and neuronal cell adhesion molecule show a strong staining of bile

  17. Engulfment of Neisseria gonorrhoeae: revealing distinct processes of bacterial entry by individual carcinoembryonic antigen-related cellular adhesion molecule family receptors.

    PubMed

    McCaw, Shannon E; Liao, Edward H; Gray-Owen, Scott D

    2004-05-01

    Individual Neisseria gonorrhoeae colony opacity-associated (Opa) protein variants can bind up to four different carcinoembryonic antigen-related cellular adhesion molecule (CEACAM) receptors. Most human cells encountered by gonococci express a combination of CEACAM receptors, thereby complicating the elucidation of intracellular signaling pathways triggered by individual receptors. Here, we compare the process of bacterial engulfment by a panel of stably transfected HeLa epithelial cell lines expressing each CEACAM receptor in isolation. CEACAM1 and CEACAM3 each contain proteinaceous transmembrane and cytoplasmic domains; however, the processes of neisserial uptake mediated by these receptors differ with respect to their susceptibilities to both tyrosine kinase inhibitors and the actin microfilament-disrupting agent cytochalasin D. Neisserial uptake mediated by glycosylphosphatidylinositol (GPI)-anchored CEACAM5 and CEACAM6 was not significantly affected by any of a broad spectrum of inhibitors tested. However, cleavage of the GPI anchor by phosphatidylinositol-specific phospholipase C reduced bacterial uptake by HeLa cells expressing CEACAM5, consistent with a single zipper-like mechanism of uptake mediated by this receptor. Regardless of the CEACAM receptor expressed, internalized gonococci were effectively killed by a microtubule-dependent process that required acidification of the bacterium-containing phagosome. Given the phase-variable nature of neisserial Opa proteins, these results indicate that the mechanism of bacterial engulfment and the cellular response to gonococcal infection depend on both the receptor specificities of the neisserial Opa protein variants expressed and the spectrum of CEACAM receptors present on target cells, each of which determines the combination of receptors ultimately engaged. PMID:15102784

  18. Expression and function of heterotypic adhesion molecules during differentiation of human skeletal muscle in culture.

    PubMed Central

    Beauchamp, J. R.; Abraham, D. J.; Bou-Gharios, G.; Partridge, T. A.; Olsen, I.

    1992-01-01

    The infiltration of skeletal muscle by leukocytes occurs in a variety of myopathies and frequently accompanies muscle degeneration and regeneration. The latter involves development of new myofibers from precursor myoblasts, and so infiltrating cells may interact with muscle at all stages of differentiation. The authors have investigated the surface expression of ligands for T-cell adhesion during the differentiation of human skeletal muscle in vitro. Myoblasts expressed low levels of ICAM-1 (CD54), which remained constant during muscle cell differentiation and could be induced by cytokines such as gamma-interferon. It is therefore likely that ICAM-1 is involved in the invasive accumulation of lymphocytes during skeletal muscle inflammation. In contrast, LFA-3 (CD58) was expressed at higher levels than ICAM-1 on myoblasts, decreased significantly during myogenesis, and was unaffected by immune mediators. Both ICAM-1 and LFA-3 were able to mediate T cell binding to myoblasts, whereas adhesion to myotubes was independent of the LFA-3 ligand. Although expressed throughout myogenesis, human leukocyte antigen class I and CD44 did not appear to mediate T cell binding. The expression of ligands that facilitate interaction of myogenic cells with lymphocytes may have important implications for myoblast transplantation. Images Figure 1 Figure 3 Figure 4 PMID:1739132

  19. Small Molecules, Inhibitors of DNA-PK, Targeting DNA Repair, and Beyond

    PubMed Central

    Davidson, David; Amrein, Lilian; Panasci, Lawrence; Aloyz, Raquel

    2012-01-01

    Many current chemotherapies function by damaging genomic DNA in rapidly dividing cells ultimately leading to cell death. This therapeutic approach differentially targets cancer cells that generally display rapid cell division compared to normal tissue cells. However, although these treatments are initially effective in arresting tumor growth and reducing tumor burden, resistance and disease progression eventually occur. A major mechanism underlying this resistance is increased levels of cellular DNA repair. Most cells have complex mechanisms in place to repair DNA damage that occurs due to environmental exposures or normal metabolic processes. These systems, initially overwhelmed when faced with chemotherapy induced DNA damage, become more efficient under constant selective pressure and as a result chemotherapies become less effective. Thus, inhibiting DNA repair pathways using target specific small molecule inhibitors may overcome cellular resistance to DNA damaging chemotherapies. Non-homologous end joining a major mechanism for the repair of double-strand breaks (DSB) in DNA is regulated in part by the serine/threonine kinase, DNA dependent protein kinase (DNA-PK). The DNA-PK holoenzyme acts as a scaffold protein tethering broken DNA ends and recruiting other repair molecules. It also has enzymatic activity that may be involved in DNA damage signaling. Because of its’ central role in repair of DSBs, DNA-PK has been the focus of a number of small molecule studies. In these studies specific DNA-PK inhibitors have shown efficacy in synergizing chemotherapies in vitro. However, compounds currently known to specifically inhibit DNA-PK are limited by poor pharmacokinetics: these compounds have poor solubility and have high metabolic lability in vivo leading to short serum half-lives. Future improvement in DNA-PK inhibition will likely be achieved by designing new molecules based on the recently reported crystallographic structure of DNA-PK. Computer based drug

  20. PFK15, a Small Molecule Inhibitor of PFKFB3, Induces Cell Cycle Arrest, Apoptosis and Inhibits Invasion in Gastric Cancer

    PubMed Central

    Zhu, Wei; Ye, Liang; Zhang, Jianzhao; Yu, Pengfei; Wang, Hongbo; Ye, Zuguang; Tian, Jingwei

    2016-01-01

    PFKFB3 (6-phosphofructo-2-kinase) synthesizes fructose 2,6-bisphosphate (F2,6P2), which is an allosteric activator of 6-phosphofructo-1-kinase (PFK-1), the rate-limiting enzyme of glycolysis. Overexpression of the PFKFB3 enzyme leads to high glycolytic metabolism, which is required for cancer cells to survive in the harsh tumor microenvironment. The objective of this study was to investigate the antitumor activity of PFK15 (1-(4-pyridinyl)-3-(2-quinolinyl)-2-propen-1-one), a small molecule inhibitor of PFKFB3, against gastric cancer and to explore its potential mechanisms. The effects of PFK15 on proliferation, apoptosis and cell cycle progression in gastric cancer cells were evaluated by cytotoxicity and apoptosis assays, flow cytometry, and western blotting. In addition, the invasion inhibition effects of PFK15 were measured by transwell invasion assay and western blot analysis, and a xenograft tumor model was used to verify the therapeutic effect of PFK15 in vivo. Results showed that PFK15 inhibited the proliferation, caused cell cycle arrest in G0/G1 phase by blocking the Cyclin-CDKs/Rb/E2F signaling pathway, and induced apoptosis through mitochondria in gastric cancer cells. Tumor volume and weight were also significantly reduced upon intraperitoneal injection with PFK15 at 25 mg/kg. In addition, PFK15 inhibited the invasion of gastric cancer cells by downregulating focal adhesion kinase (FAK) expression and upregulating E-cadherin expression. Taken together, our findings indicate that PFK15 is a promising anticancer drug for treating gastric cancer. PMID:27669567

  1. Dietary arginine enhances adhesion molecule and T helper 2 cytokine expression in mice with gut-derived sepsis.

    PubMed

    Yeh, Chiu-Li; Hsu, Chun-Sen; Chiu, Wan-Chun; Hou, Yu-Chen; Yeh, Sung-Ling

    2006-02-01

    This study investigated the effects of arginine (Arg) on cellular adhesion molecules and intracellular Th1/Th2 cytokine expressions in mice with polymicrobial sepsis. Myeloperoxidase activity in organs was also analyzed to identify the extent of tissue injury resulting from neutrophil infiltration. Mice were randomly assigned to a normal group (NC), a control group, or an Arg group. The NC group was fed a standard chow diet. The control group was fed a common semipurified diet, and in the Arg group, part of the casein was replaced by Arg, which provided 2% of the total calories. After 3 weeks, sepsis was induced by cecal ligation and puncture (CLP) in the control and Arg groups. Mice in the experimental groups were sacrificed at 0, 6, 12, and 24 h after CLP, whereas mice in the NC group were sacrificed when the CLP was performed. Blood and organ samples were immediately collected for further analysis. Results showed that compared with the control group, plasma intracellular adhesion molecule-1 levels were significantly higher in the Arg group 12 and 24 h after CLP. Lymphocyte interferon-gamma expression in the Arg groups was significantly lower, whereas interleukin (IL)-4 expression was higher than the control group at various time points after CLP. The expression of lymphocyte CD11a/CD18 was significantly higher in the Arg group 6, 12, and 24 h after CLP than those of the corresponding control group and the NC group. PMN expressions of CD11b/CD18 in the Arg groups were higher than those in the control group at 12 and 24 h after CLP. The Arg group had higher IL-6 levels at 6 and 12 h in the kidney and intestine and 12 h in the lung after CLP. Higher myeloperoxidase activities were observed in the Arg groups at 24 h after CLP than those in the control group in various organs. These findings suggest that pretreatment with an Arg-supplemented diet enhances adhesion molecule and inflammatory cytokine expression during sepsis, which may aggravate the inflammatory

  2. Small Molecule Inhibitors of BAF; A Promising Family of Compounds in HIV-1 Latency Reversal

    PubMed Central

    Stoszko, Mateusz; De Crignis, Elisa; Rokx, Casper; Khalid, Mir Mubashir; Lungu, Cynthia; Palstra, Robert-Jan; Kan, Tsung Wai; Boucher, Charles; Verbon, Annelies; Dykhuizen, Emily C.; Mahmoudi, Tokameh

    2015-01-01

    Persistence of latently infected cells in presence of Anti-Retroviral Therapy presents the main obstacle to HIV-1 eradication. Much effort is thus placed on identification of compounds capable of HIV-1 latency reversal in order to render infected cells susceptible to viral cytopathic effects and immune clearance. We identified the BAF chromatin remodeling complex as a key player required for maintenance of HIV-1 latency, highlighting its potential as a molecular target for inhibition in latency reversal. Here, we screened a recently identified panel of small molecule inhibitors of BAF (BAFi's) for potential to activate latent HIV-1. Latency reversal was strongly induced by BAFi's Caffeic Acid Phenethyl Ester and Pyrimethamine, two molecules previously characterized for clinical application. BAFi's reversed HIV-1 latency in cell line based latency models, in two ex vivo infected primary cell models of latency, as well as in HIV-1 infected patient's CD4 + T cells, without inducing T cell proliferation or activation. BAFi-induced HIV-1 latency reversal was synergistically enhanced upon PKC pathway activation and HDAC-inhibition. Therefore BAFi's constitute a promising family of molecules for inclusion in therapeutic combinatorial HIV-1 latency reversal. PMID:26870822

  3. Small Molecule Inhibitors of BAF; A Promising Family of Compounds in HIV-1 Latency Reversal.

    PubMed

    Stoszko, Mateusz; De Crignis, Elisa; Rokx, Casper; Khalid, Mir Mubashir; Lungu, Cynthia; Palstra, Robert-Jan; Kan, Tsung Wai; Boucher, Charles; Verbon, Annelies; Dykhuizen, Emily C; Mahmoudi, Tokameh

    2016-01-01

    Persistence of latently infected cells in presence of Anti-Retroviral Therapy presents the main obstacle to HIV-1 eradication. Much effort is thus placed on identification of compounds capable of HIV-1 latency reversal in order to render infected cells susceptible to viral cytopathic effects and immune clearance. We identified the BAF chromatin remodeling complex as a key player required for maintenance of HIV-1 latency, highlighting its potential as a molecular target for inhibition in latency reversal. Here, we screened a recently identified panel of small molecule inhibitors of BAF (BAFi's) for potential to activate latent HIV-1. Latency reversal was strongly induced by BAFi's Caffeic Acid Phenethyl Ester and Pyrimethamine, two molecules previously characterized for clinical application. BAFi's reversed HIV-1 latency in cell line based latency models, in two ex vivo infected primary cell models of latency, as well as in HIV-1 infected patient's CD4 + T cells, without inducing T cell proliferation or activation. BAFi-induced HIV-1 latency reversal was synergistically enhanced upon PKC pathway activation and HDAC-inhibition. Therefore BAFi's constitute a promising family of molecules for inclusion in therapeutic combinatorial HIV-1 latency reversal. PMID:26870822

  4. Monoclonal antibodies to human lymphocyte homing receptors define a novel class of adhesion molecules on diverse cell types

    PubMed Central

    1989-01-01

    A 90-kD lymphocyte surface glycoprotein, defined by monoclonal antibodies of the Hermes series, is involved in lymphocyte recognition of high endothelial venules (HEV). Lymphocyte gp90Hermes binds in a saturable, reversible fashion to the mucosal vascular addressin (MAd), a tissue-specific endothelial cell adhesion molecule for lymphocytes. We and others have recently shown that the Hermes antigen is identical to or includes CD44 (In[Lu]-related p80), human Pgp-1, and extracellular matrix receptor III-molecules reportedly expressed on diverse cell types. Here, we examine the relationship between lymphoid and nonlymphoid Hermes antigens using serologic, biochemical, and, most importantly, functional assays. Consistent with studies using mAbs to CD44 or Pgp-1, mAbs against five different epitopes on lymphocyte gp90Hermes reacted with a wide variety of nonhematolymphoid cells in diverse normal human tissues, including many types of epithelium, mesenchymal elements such as fibroblasts and smooth muscle, and a subset of glia in the central nervous system. To ask whether these non- lymphoid molecules might also be functionally homologous to lymphocyte homing receptors, we assessed their ability to interact with purified MAd using fluorescence energy transfer techniques. The Hermes antigen isolated from both glial cells and fibroblasts--which express a predominant 90-kD form similar in relative molecular mass, isoelectric point, and protease sensitivity to lymphocyte gp90Hermes--was able to bind purified MAd. In contrast, a 140-160-kD form of the Hermes antigen isolated from squamous epithelial cells lacked this capability. Like lymphocyte binding to mucosal HEV, the interaction between glial gp90Hermes and MAd is inhibited by mAb Hermes-3, but not Hermes-1, suggesting that similar molecular domains are involved in the two binding events. The observation that the Hermes/CD44 molecules derived from several nonlymphoid cell types display binding domains homologous to those

  5. Effect of junctional adhesion molecule-2 expression on cell growth, invasion and migration in human colorectal cancer

    PubMed Central

    ZHAO, HUISHAN; YU, HEFEN; MARTIN, TRACEY A.; ZHANG, YUXIANG; CHEN, GANG; JIANG, WEN G.

    2016-01-01

    The junctional adhesion molecule (JAMs) family belongs to the immunoglobulin subfamily involved in the formation of tight junctions (TJ) in both endothelial and epithelial cells. Aberrant expression of JAM-2 is associated with cancer progression but little work has been carried out in discovering how this affects changes in cell behaviour. The present study aimed to examine the expression of JAM-2 in human colon cancer specimens and cell lines and its role in the development of colon cancer. JAM-2 expression in human colon cancer specimens (normal, n=75; cancer, n=94) and cell lines was analysed using quantitative real-time PCR and conventional RT-PCR. Colon cancer cells were stably transfected with a mammalian expression vector to overexpress JAM-2-Flag. The effect on growth, adhesion and migration following overexpression of JAM-2 was then investigated using in vitro models. TJ function was assessed using a trans-epithelial resistance assay (TER, with an EVOM voltammeter). JAM-2 was lowly expressed in colon cancer cells such as RKO, HT115. JAM-2 overexpression in RKO cells (RKO-JAM-2) and HT115 cells (HT115-JAM-2) showed retarded adhesion (P<0.05). An in vivo tumour model showed that RKO-JAM-2 had significantly reduced growth (P<0.05), invasion (P<0.05) and migration (P<0.05) as well as in HT115-JAM-2, except on proliferation and migration. Expression of JAM-2 resulted in a significant increase in TER and decrease in permeability of polarized monolayers (P<0.05). Further analysis of JAM-2 transcript levels against clinical aspects demonstrated that the decreasing JAM-2 expression correlated to disease progression, metastasis and poor survival. Taken together, JAM-2 may function as a putative tumour suppressor in the progression and metastasis of colorectal cancer. PMID:26782073

  6. Novel secreted isoform of adhesion molecule ICAM-4: Potential regulator of membrane-associated ICAM-4 interactions

    SciTech Connect

    Lee, Gloria; Spring, Frances A.; Parons, Stephen F.; Mankelow, Tosti J.; Peters, Luanne L.; Koury, Mark J.; Mohandas, Narla; Anstee, David J.; Chasis, Joel Anne

    2003-02-18

    ICAM-4, a newly characterized adhesion molecule, is expressed early in human erythropoiesis and functions as a ligand for binding a4b1 and aV integrin-expressing cells. Within the bone marrow, erythroblasts surround central macrophages forming erythroblastic islands. Evidence suggests that these islands are highly specialized subcompartments where cell adhesion events, in concert with cytokines, play critical roles in regulating erythropoiesis and apoptosis. Since erythroblasts express a4b1 and ICAM-4 and macrophages exhibit aV, ICAM-4 is an attractive candidate for mediating cellular interactions within erythroblastic islands. To determine whether ICAM-4 binding properties are conserved across species, we first cloned and sequenced the murine homologue. The translated amino acid sequence showed 68 percent overall identity with human ICAM-4. Using recombinant murine ICAM-4 extracellular domains, we discovered that hematopoietic a4b1-expressing HEL cells and non-hematopoietic aV-expressing FLY cells adhered to mouse ICAM-4. Cell adhesion studies showed that FLY and HEL cells bound to mouse and human proteins with similar avidity. These data strongly suggest conservation of integrin-binding properties across species. Importantly, we characterized a novel second splice cDNA that would be predicted to encode an ICAM-4 isoform, lacking the membrane-spanning domain. Erythroblasts express both isoforms of ICAM-4. COS-7 cells transfected with GFP constructs of prototypic or novel ICAM-4 cDNA showed different cellular localization patterns. Moreover, analysis of tissue culture medium revealed that the novel ICAM-4 cDNA encodes a secreted protein. We postulate that secretion of this newly described isoform, ICAM-4S, may modulate binding of membrane-associated ICAM-4 and could thus play a critical regulatory role in erythroblast molecular attachments.

  7. Sequential expression of adhesion and costimulatory molecules in graft-versus-host disease target organs after murine bone marrow transplantation across minor histocompatibility antigen barriers.

    PubMed

    Eyrich, Matthias; Burger, Gudrun; Marquardt, Katja; Budach, Wilfried; Schilbach, Karin; Niethammer, Dietrich; Schlegel, Paul G

    2005-05-01

    Graft-versus-host disease (GVHD) is a potentially fatal complication after allogeneic bone marrow transplantation. However, few data exist thus far on the molecular signals governing leukocyte trafficking during the disease. We therefore investigated the sequential pattern of distinct adhesion, costimulatory, and apoptosis-related molecules in GVHD organs (ileum, colon, skin, and liver) after transplantation across minor histocompatibility barriers (B10.D2 --> BALB/c, both H-2d). To distinguish changes induced by the conditioning regimen from effects achieved by allogeneic cell transfer, syngeneic transplant recipients (BALB/c --> BALB/c) and irradiated nontransplanted mice were added as controls. Irradiation upregulated the expression of vascular cell adhesion molecule (VCAM)-1, intercellular adhesion molecule (ICAM)-l, and B7-2 in ileum, as well as VCAM-1 and B7-2 in colon, on day 3 in all animals. Whereas in syngeneic mice these effects were reversed from day 9 on, allogeneic recipients showed further upregulation of VCAM-1, ICAM-1, B7-1, and B7-2 in these organs on day 22, when GVHD became clinically evident. Infiltration of CD4+ and CD8+ donor T cells was noted on day 9 in skin and liver and on day 22 in ileum and colon. Surprisingly, the expression of several other adhesion molecules, such as ICAM-2, platelet-endothelial cell adhesion molecule 1, E-selectin, and mucosal addressin cell adhesion molecule 1, did not change. Proapoptotic and antiapoptotic markers were balanced in GVHD organs with the exception of spleen, in which a preferential expression of the proapoptotic Bax could be noted. Our results indicate that irradiation-induced upregulation of VCAM-1, ICAM-1, and B7-2 provides early costimulatory signals to incoming donor T cells in the intestine, followed by a cascade of proinflammatory signals in other organs once the alloresponse is established.

  8. L1 adhesion molecule on mouse leukocytes: regulation and involvement in endothelial cell binding.

    PubMed

    Hubbe, M; Kowitz, A; Schirrmacher, V; Schachner, M; Altevogt, P

    1993-11-01

    L1 is a cell surface glycoprotein of the immunoglobulin superfamily which was initially shown to mediate adhesion between neural cells. Recently we have reported that L1 is expressed by bone marrow cells and the majority of mature lymphocytes (Kowitz et al., Eur. J. Immunol. 1992. 22: 1199-1205). To analyze the function of L1 on leukocytes we studied its regulation following cell activation. In vitro activation of B lymphocytes with lipopolysaccharide or T lymphocytes with phorbol 12-myristate 13-acetate/Ca2+ ionophore, concanavalin A or anti-CD3 monoclonal antibody as well as in vivo activation of V beta 8+ T cells with staphylococcal enterotoxin B (SEB) revealed a down-regulation of L1 within 48 h. A rapid loss of L1 expression was seen when mouse neutrophils were activated with PMA alone. This rapid loss paralleled the shedding of L-selectin. We also studied a possible role of L1 in the binding of leukocytes to endothelial cells. ESb-MP lymphoma cells with a high expression of L1 (L1hi) could bind to bend3 endothelioma cells without prior activation with inflammatory cytokines. The interaction was inhibited by anti-L1 antibodies. In contrast, ESb-MP cells with low L1 expression (L1lo) were only marginally bound. Latex beads coated with affinity-isolated L1 antigen were also able to bind to the endothelioma cells in a specific fashion. The binding of ESb-MP lymphoma cells required Ca2+ and Mg2+ ions and was sensitive to cold temperature. Since the endothelioma cells did not express L1 the binding mechanism studied here is distinct from the established L1-L1 homotypic interaction. It is possible that the novel L1-mediated adhesion pathway involves an unidentified ligand and could play a role in leukocyte migration.

  9. L1 adhesion molecule on mouse leukocytes: regulation and involvement in endothelial cell binding.

    PubMed

    Hubbe, M; Kowitz, A; Schirrmacher, V; Schachner, M; Altevogt, P

    1993-11-01

    L1 is a cell surface glycoprotein of the immunoglobulin superfamily which was initially shown to mediate adhesion between neural cells. Recently we have reported that L1 is expressed by bone marrow cells and the majority of mature lymphocytes (Kowitz et al., Eur. J. Immunol. 1992. 22: 1199-1205). To analyze the function of L1 on leukocytes we studied its regulation following cell activation. In vitro activation of B lymphocytes with lipopolysaccharide or T lymphocytes with phorbol 12-myristate 13-acetate/Ca2+ ionophore, concanavalin A or anti-CD3 monoclonal antibody as well as in vivo activation of V beta 8+ T cells with staphylococcal enterotoxin B (SEB) revealed a down-regulation of L1 within 48 h. A rapid loss of L1 expression was seen when mouse neutrophils were activated with PMA alone. This rapid loss paralleled the shedding of L-selectin. We also studied a possible role of L1 in the binding of leukocytes to endothelial cells. ESb-MP lymphoma cells with a high expression of L1 (L1hi) could bind to bend3 endothelioma cells without prior activation with inflammatory cytokines. The interaction was inhibited by anti-L1 antibodies. In contrast, ESb-MP cells with low L1 expression (L1lo) were only marginally bound. Latex beads coated with affinity-isolated L1 antigen were also able to bind to the endothelioma cells in a specific fashion. The binding of ESb-MP lymphoma cells required Ca2+ and Mg2+ ions and was sensitive to cold temperature. Since the endothelioma cells did not express L1 the binding mechanism studied here is distinct from the established L1-L1 homotypic interaction. It is possible that the novel L1-mediated adhesion pathway involves an unidentified ligand and could play a role in leukocyte migration. PMID:8223869

  10. The role of cell adhesion molecules in visual circuit formation: From neurite outgrowth to maps and synaptic specificity

    PubMed Central

    Missaire, Mégane

    2015-01-01

    ABSTRACT The formation of visual circuitry is a multistep process that involves cell–cell interactions based on a range of molecular mechanisms. The correct implementation of individual events, including axon outgrowth and guidance, the formation of the topographic map, or the synaptic targeting of specific cellular subtypes, are prerequisites for a fully functional visual system that is able to appropriately process the information captured by the eyes. Cell adhesion molecules (CAMs) with their adhesive properties and their high functional diversity have been identified as key actors in several of these fundamental processes. Because of their growth‐promoting properties, CAMs play an important role in neuritogenesis. Furthermore, they are necessary to control additional neurite development, regulating dendritic spacing and axon pathfinding. Finally, trans‐synaptic interactions of CAMs ensure cell type‐specific connectivity as a basis for the establishment of circuits processing distinct visual features. Recent discoveries implicating CAMs in novel mechanisms have led to a better general understanding of neural circuit formation, but also revealed an increasing complexity of their function. This review aims at describing the different levels of action for CAMs to shape neural connectivity, with a special focus on the visual system. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 75: 569–583, 2015 PMID:25649254

  11. New Cell Adhesion Molecules in Human Ischemic Cardiomyopathy. PCDHGA3 Implications in Decreased Stroke Volume and Ventricular Dysfunction

    PubMed Central

    Tarazón, Estefanía; García-Manzanares, María; Montero, José Anastasio; Cinca, Juan; Portolés, Manuel; Rivera, Miguel; Roselló-Lletí, Esther

    2016-01-01

    Background Intercalated disks are unique structures in cardiac tissue, in which adherens junctions, desmosomes, and GAP junctions co-localize, thereby facilitating cardiac muscle contraction and function. Protocadherins are involved in these junctions; however, their role in heart physiology is poorly understood. We aimed to analyze the transcriptomic profile of adhesion molecules in patients with ischemic cardiomyopathy (ICM) and relate the changes uncovered with the hemodynamic alterations and functional depression observed in these patients. Methods and Results Twenty-three left ventricular tissue samples from patients diagnosed with ICM (n = 13) undergoing heart transplantation and control donors (CNT, n = 10) were analyzed using RNA sequencing. Forty-two cell adhesion genes involved in cellular junctions were differentially expressed in ICM myocardium. Notably, the levels of protocadherin PCDHGA3 were related with the stroke volume (r = –0.826, P = 0.003), ejection fraction (r = –0.793, P = 0.004) and left ventricular end systolic and diastolic diameters (r = 0.867, P = 0.001; r = 0.781, P = 0.005, respectively). Conclusions Our results support the importance of intercalated disks molecular alterations, closely involved in the contractile function, highlighting its crucial significance and showing gene expression changes not previously described. Specifically, altered PCDHGA3 gene expression was strongly associated with reduced stroke volume and ventricular dysfunction in ICM, suggesting a relevant role in hemodynamic perturbations and cardiac performance for this unexplored protocadherin. PMID:27472518

  12. Intercellular adhesion molecule 1 serves as a primary cognate receptor for the Type IV pilus of nontypeable Haemophilus influenzae.

    PubMed

    Novotny, Laura A; Bakaletz, Lauren O

    2016-08-01

    Nontypeable Haemophilus influenzae (NTHI) utilizes the Type IV pilus (Tfp) to adhere to respiratory tract epithelial cells thus colonizing its human host; however, the host cell receptor to which this adhesive protein binds is unknown. From a panel of receptors engaged by Tfp expressed by other bacterial species, we showed that the majority subunit of NTHI Tfp, PilA, bound to intercellular adhesion molecule 1 (ICAM1) and that this interaction was both specific and of high affinity. Further, Tfp-expressing NTHI inoculated on to polarized respiratory tract epithelial cells that expressed ICAM1 were significantly more adherent compared to Tfp-deficient NTHI or NTHI inoculated on to epithelial cells to which ICAM1 gene expression was silenced. Moreover, pre-incubation of epithelial cells with recombinant soluble PilA (rsPilA) blocked adherence of NTHI, an outcome that was abrogated by admixing rsPilA with ICAM1 prior to application on to the target cells. Epithelial cells infected with adenovirus or respiratory syncytial virus showed increased expression of ICAM1; this outcome supported augmented adherence of Tfp-expressing NTHI. Collectively, these data revealed the cognate receptor for NTHI Tfp as ICAM1 and promote continued development of a Tfp-targeted vaccine for NTHI-induced diseases of the airway wherein upper respiratory tract viruses play a key predisposing role.

  13. Blocking of lung endothelial cell adhesion molecule-1 (Lu-ECAM-1) inhibits murine melanoma lung metastasis.

    PubMed

    Zhu, D; Cheng, C F; Pauli, B U

    1992-06-01

    The 90-kD lung endothelial cell adhesion molecule-1 (Lu-ECAM-1) selectively promotes Ca(2+)-dependent adhesion of lung-metastatic B16 melanoma cells. Corresponding with their metastatic performance, high lung-metastatic B16-F10 melanoma cells bind in significantly higher numbers to Lu-ECAM-1 than their intermediate and low lung-metastatic counterparts B16-L8-F10 and B16-F0, respectively. Maximum attachment is observed at a density of approximately 2.4 x 10(2) Lu-ECAM-1 sites/microns2 of plastic surface. B16 melanoma cell binding to Lu-ECAM-1 is blocked by mAb 6D3 and is competitively inhibited by soluble Lu-ECAM-1. C57B1/6 mice passively immunized with anti-Lu-ECAM-1 mAb 6D3 or actively immunized with purified Lu-ECAM-1 exhibit an anti-Lu-ECAM-1 antibody titer-dependent reduction in the number of B16 experimental metastases. Lu-ECAM-1 promotes neither binding nor metastasis of other lung-metastatic tumor cells (e.g., KLN205). Our data indicate that an "antiadhesion" therapy directed at interfering with the adherence of blood-borne tumor cells to organ-specific vascular endothelium is efficient in the control of metastasis formation in selective organ sites.

  14. Blocking of lung endothelial cell adhesion molecule-1 (Lu-ECAM-1) inhibits murine melanoma lung metastasis.

    PubMed Central

    Zhu, D; Cheng, C F; Pauli, B U

    1992-01-01

    The 90-kD lung endothelial cell adhesion molecule-1 (Lu-ECAM-1) selectively promotes Ca(2+)-dependent adhesion of lung-metastatic B16 melanoma cells. Corresponding with their metastatic performance, high lung-metastatic B16-F10 melanoma cells bind in significantly higher numbers to Lu-ECAM-1 than their intermediate and low lung-metastatic counterparts B16-L8-F10 and B16-F0, respectively. Maximum attachment is observed at a density of approximately 2.4 x 10(2) Lu-ECAM-1 sites/microns2 of plastic surface. B16 melanoma cell binding to Lu-ECAM-1 is blocked by mAb 6D3 and is competitively inhibited by soluble Lu-ECAM-1. C57B1/6 mice passively immunized with anti-Lu-ECAM-1 mAb 6D3 or actively immunized with purified Lu-ECAM-1 exhibit an anti-Lu-ECAM-1 antibody titer-dependent reduction in the number of B16 experimental metastases. Lu-ECAM-1 promotes neither binding nor metastasis of other lung-metastatic tumor cells (e.g., KLN205). Our data indicate that an "antiadhesion" therapy directed at interfering with the adherence of blood-borne tumor cells to organ-specific vascular endothelium is efficient in the control of metastasis formation in selective organ sites. Images PMID:1601982

  15. The Na-K-ATPase α1β1 heterodimer as a cell adhesion molecule in epithelia

    PubMed Central

    Dada, Laura A.; Tokhtaeva, Elmira; Sachs, George

    2012-01-01

    The ion gradients generated by the Na-K-ATPase play a critical role in epithelia by driving transepithelial transport of various solutes. The efficiency of this Na-K-ATPase-driven vectorial transport depends on the integrity of epithelial junctions that maintain polar distribution of membrane transporters, including the basolateral sodium pump, and restrict paracellular diffusion of solutes. The review summarizes the data showing that, in addition to pumping ions, the Na-K-ATPase located at the sites of cell-cell junction acts as a cell adhesion molecule by interacting with the Na-K-ATPase of the adjacent cell in the intercellular space accompanied by anchoring to the cytoskeleton in the cytoplasm. The review also discusses the experimental evidence on the importance of a specific amino acid region in the extracellular domain of the Na-K-ATPase β1 subunit for the Na-K-ATPase trans-dimerization and intercellular adhesion. Furthermore, a possible role of N-glycans linked to the Na-K-ATPase β1 subunit in regulation of epithelial junctions by modulating β1-β1 interactions is discussed. PMID:22277755

  16. Selective induction of cell adhesion molecules by proinflammatory mediators in human cardiac microvascular endothelial cells in culture

    PubMed Central

    Yan, Jun; Nunn, Adrian D; Thomas, Regi

    2010-01-01

    Pro-inflammatory mediators can dramatically alter many responses of cultured endothelial cells in vitro, which are relevant to understanding the role played by the endothelium in inflammation in vivo. The aim of this study was to determine the ability of a comprehensive array of pro-inflammatory stimuli to modulate Cell Adhesion Molecule (CAM) expression in cultures of human microvascular cardiac endothelial cells (HMVEC.c). Cell ELISA, immunocy-tochemistry and flow cytometry were used to measure the CAM expressions in HMVEC.c in response to interleukins, TNF-α and LPS. Passage matched HMVEC.c from different donors showed different CAM expression profiles, confirming inherent variability in endothelial cells. Endothelial cells from different parts of the vasculature are exposed to different cytokines and thus different protein expression profiles. A thorough understanding of these innate differences in expression pattern of the microvasculatures of cardiac tissues might allow us the opportunity to target these tissues selectively. PMID:21072266

  17. Quantitative determination of the organ distribution of the cell adhesion molecule cell-CAM 105 by radioimmunoassay

    SciTech Connect

    Odin, P.; Oebrink, B. )

    1987-07-01

    The authors have previously identified a 105,000-Da plasma membrane glycoprotein, denoted cell-CAM 105, that is involved in intercellular adhesion of reaggregating rat hepatocytes. In this communication they report on the development of a radioimmunoassay for cell-CAM 105, employing purified cell-CAM 105, specific antisera against the molecule, and formalin-fixed protein A-containing staphylococci for precipitation of the immune complexes. The assay was shown to be sensitive, specific, precise, rapid, and easy to perform. They used this radioimmunoassay in investigations of the occurrence of cell-CAM 105 in different rat organs. Cell-CAM 105 was present in a wide spectrum of organs in varying amounts. The highest concentrations were found in the gastrointestinal tract, liver, some secretory glands, vagina, kidney, and lung. The results were confirmed by immunoblotting, which revealed one distinct protein component, corresponding to cell-CAM 105, in each positive organ.

  18. A novel nondevelopmental role of the sax-7/L1CAM cell adhesion molecule in synaptic regulation in Caenorhabditis elegans.

    PubMed

    Opperman, Karla; Moseley-Alldredge, Melinda; Yochem, John; Bell, Leslie; Kanayinkal, Tony; Chen, Lihsia

    2015-02-01

    The L1CAM family of cell adhesion molecules is a conserved set of single-pass transmembrane proteins that play diverse roles required for proper nervous system development and function. Mutations in L1CAMs can cause the neurological L1 syndrome and are associated with autism and neuropsychiatric disorders. L1CAM expression in the mature nervous system suggests additional functions besides the well-characterized developmental roles. In this study, we demonstrate that the gene encoding the Caenorhabditis elegans L1CAM, sax-7, genetically interacts with gtl-2, as well as with unc-13 and rab-3, genes that function in neurotransmission. These sax-7 genetic interactions result in synthetic phenotypes that are consistent with abnormal synaptic function. Using an inducible sax-7 expression system and pharmacological reagents that interfere with cholinergic transmission, we uncovered a previously uncharacterized nondevelopmental role for sax-7 that impinges on synaptic function. PMID:25488979

  19. Soluble intercellular adhesion molecules in human schistosomiasis: correlations with disease severity and decreased responsiveness to egg antigens.

    PubMed Central

    Secor, W E; dos Reis, M G; Ramos, E A; Matos, E P; Reis, E A; do Carmo, T M; Harn, D A

    1994-01-01

    Granuloma formation, the principal pathologic consequence of infection with Schistosoma mansoni, is a complex process involving intricate cell-cell interactions in which intercellular adhesion molecules are likely to participate. To examine this possibility, sera of schistosomiasis patients in various clinical groups were assayed for the presence of soluble intercellular adhesion molecule 1 (sICAM-1) and soluble E-selectin (sE-selectin). Comparisons were made between groups with different infection intensities (as predicted by fecal egg count) as well as between groups with severe (hepatosplenic) or milder (intestinal) pathology. All groups had elevated levels of sICAM-1 compared with controls. Also, patients in the high egg-excreting and hepatosplenic groups had significantly higher levels of serum sICAM-1 than patients in the low-egg-excreting and intestinal groups, respectively. The levels of sE-selectin were significantly elevated in the sera of all patients except those in the hepatosplenic group compared with controls. Patients in the intestinal group had significantly higher levels of sE-selectin in their sera than did hepatosplenic group patients, but serum sE-selectin levels of high- and low-egg-excreting patients were comparable. A striking finding of this study was the inverse correlation observed between sICAM-1 levels and peripheral blood mononuclear cell responses to schistosome soluble egg antigens (SEA) but not with responses to other schistosome antigens, purified protein derivative, or mitogen. Because ICAM-1 can perform a costimulatory function in antigen-presenting cell-T cell interactions, it is possible that shedding of ICAM-1 in the granuloma microenvironment interrupts proper costimulation, leading to unresponsive SEA-specific T cells. In this way, sICAM-1 could be one factor contributing to the observed modulation of cellular responses to SEA in chronic human schistosomiasis. PMID:7516309

  20. Identification of positive and negative regulatory elements governing cell-type-specific expression of the neural cell adhesion molecule gene.

    PubMed Central

    Hirsch, M R; Gaugler, L; Deagostini-Bazin, H; Bally-Cuif, L; Goridis, C

    1990-01-01

    The neural cell adhesion molecule (NCAM) is one of the most prevalent cell adhesion molecules in vertebrates. Its expression is subject to complex cell-type- and developmental-stage-dependent regulation. To study this regulation at the level of transcription, we analyzed the promoter region of the mouse NCAM gene. The NCAM promoter did not contain a typical TATA box. Transcription started at several sites that were used indiscriminately by different cell types, implying that the different NCAM isoforms are expressed from a single promoter. Sequences responsible for both promotion and inhibition of transcription resided within 840 base pairs upstream of the main transcriptional start site. The sequence from positions -645 to -37 relative to the translation initiation site directed high levels of expression in NCAM-expressing N2A cells. The same fragment was six times less active but still significantly active in L cells, but this activity was repressed by inclusion of an additional upstream segment. We mapped eight domains of interactions with nuclear proteins within the 840-base-pair region. The segment with maximum promoter activity contained two adjacent footprints, the occupation of which appeared to be mutually exclusive. One of them corresponded to an Sp1-factor-binding consensus site, the other one bound a factor with nuclear factor I activity. The single protected domain in the fragment harboring a repressor activity consisted of a GGA repeat resembling negative regulatory elements in other promoters. Three adjacent binding sites occupied an A + T-rich segment and contained ATTA motifs also found in the recognition elements of homeodomain proteins. These results show that negative and positive elements interact to regulate the tissue-specific patterns of expression of the NCAM gene and indicate that a factor related to nuclear factor I is involved in its transcriptional control. Images PMID:2325642

  1. Expression of E-Selectin, P-Selectin, and Intercellular Adhesion Molecule-1 during Experimental Murine Listeriosis

    PubMed Central

    López, Santiago; Prats, Neus; Marco, Alberto Jesús

    1999-01-01

    The expression of adhesion molecules E-selectin, P-selectin, and intercellular adhesion molecule-1 (ICAM-1) was immunohistochemically investigated during the course of experimental murine listeriosis. Infection was monitored by microbiological count of blood, liver, and spleen. After an early generalized expression of P-selectin and ICAM-1, a later regulation occurred specifically to areas of inflammation. Expression of E-selectin was faint and inconstantly detected in all of the studied organs. In the liver, typical lesions of murine listeriosis were related to the expression of ICAM-1 on sinusoidal endothelial cells and the biliary system and to the de novo expression of P-selectin in hepatic portal vessels. Inflammation in the spleen was related to the expression of ICAM-1 on red pulp sinusoidal cells, especially in the marginal sinus. High endothelial venules of inflamed lymph nodes also expressed P-selectin and ICAM-1. Lesions in the central nervous system appeared on day 3 after infection as a pyogranulomatous leptomeningitis associated with an intense expression of P-selectin and ICAM-1 in meningeal vessels, especially those in the hippocampal sulcus, suggesting a way through which inflammation initially reach the central nervous system during experimental murine listeriosis. Leptomeningitis was followed by the presence of ventriculitis, which was related to the up-regulation of ICAM-1 on choroid plexus epithelial cells, periventricular vessels and ependymal cells. Up-regulation of P-selectin and ICAM-1 during experimental murine listeriosis could play an important role in the recruitment of leukocytes, especially to the liver, lymphoid organs, and central nervous system. PMID:10514421

  2. Platelet endothelial cell adhesion molecule-1 modulates endothelial cell motility through the small G-protein Rho.

    PubMed

    Gratzinger, Dita; Canosa, Sandra; Engelhardt, Britta; Madri, Joseph A

    2003-08-01

    Platelet endothelial cell adhesion molecule-1 (PECAM-1), an immunoglobulin family vascular adhesion molecule, is involved in endothelial cell migration and angiogenesis (1, 2). We found that endothelial cells lacking PECAM-1 exhibit increased single cell motility and extension formation but poor wound healing migration, reminiscent of cells in which Rho activity has been suppressed by overexpressing a GTPase-activating protein (3). The ability of PECAM-1 to restore wound healing migration to PECAM-1-deficient cells was independent of its extracellular domain or signaling via its immunoreceptor tyrosine-based inhibitory motif. PECAM-1-deficient endothelial cells had a selective defect in RhoGTP loading, and inhibition of Rho activity mimicked the PECAM-1-deficient phenotype of increased chemokinetic single cell motility at the expense of coordinated wound healing migration. The wound healing advantage of PECAM-1-positive endothelial cells was not only Rho mediated but pertussis toxin inhibitable, characteristic of migration mediated by heterotrimeric G-protein-linked seven-transmembrane receptor signaling such as signaling in response to the serum sphingolipid sphingosine-1-phosphate (S1P) (4, 5). Indeed, we found that the wound healing defect of PECAM-1 null endothelial cells is minimized in sphingolipid-depleted media; moreover, PECAM-1 null endothelial cells fail to increase their migration in response to S1P. We have also found that PECAM-1 localizes to rafts and that in its absence heterotrimeric G-protein components are differentially recruited to rafts, providing a potential mechanism for PECAM-1-mediated coordination of S1P signaling. PECAM-1 may thus support the effective S1P/RhoGTP signaling required for wound healing endothelial migration by allowing for the spatially directed, coordinated activation of Galpha signaling pathways. PMID:12890700

  3. SNPs in the neural cell adhesion molecule 1 gene (NCAM1) may be associated with human neural tube defects

    PubMed Central

    Deak, Kristen L.; Boyles, Abee L.; Etchevers, Heather C.; Melvin, Elizabeth C.; Siegel, Deborah G.; Graham, Felicia L.; Slifer, Susan H.; Enterline, David S.; George, Timothy M.; Vekemans, Michel; McClay, David; Bassuk, Alexander G.; Kessler, John A.; Linney, Elwood; Gilbert, John R.

    2011-01-01

    Neural tube defects (NTDs) are common birth defects, occurring in approximately 1/1,000 births; both genetic and environmental factors are implicated. To date, no major genetic risk factors have been identified. Throughout development, cell adhesion molecules are strongly implicated in cell–cell interactions, and may play a role in the formation and closure of the neural tube. To evaluate the role of neural cell adhesion molecule 1 (NCAM1) in risk of human NTDs, we screened for novel single-nucleotide polymorphisms (SNPs) within the gene. Eleven SNPs across NCAM1 were genotyped using TaqMan. We utilized a family-based approach to evaluate evidence for association and/or linkage disequilibrium. We evaluated American Caucasian simplex lumbosacral myelomeningocele families (n=132 families) using the family based association test (FBAT) and the pedigree disequilibrium test (PDT). Association analysis revealed a significant association between risk for NTDs and intronic SNP rs2298526 using both the FBAT test (P=0.0018) and the PDT (P=0.0025). Using the HBAT version of the FBAT to look for haplotype association, all pairwise comparisons with SNP rs2298526 were also significant. A replication study set, consisting of 72 additional families showed no significant association; however, the overall trend for overtransmission of the less common allele of SNP rs2298526 remained significant in the combined sample set. In addition, we analyzed the expression pattern of the NCAM1 protein in human embryos, and while NCAM1 is not expressed within the neural tube at the time of closure, it is expressed in the surrounding and later in differentiated neurons of the CNS. These results suggest variations in NCAM1 may influence risk for human NTDs. PMID:15883837

  4. Virtual Ligand Screening of the p300/CBP Histone Acetyltransferase: Identification of a Selective Small Molecule Inhibitor

    PubMed Central

    Bowers, Erin M.; Yan, Gai; Mukherjee, Chandrani; Orry, Andrew; Wang, Ling; Holbert, Marc A.; Crump, Nicholas T.; Hazzalin, Catherine A.; Liszczak, Glen; Yuan, Hua; Larocca, Cecilia; Saldanha, S. Adrian; Abagyan, Ruben; Sun, Yan; Meyers, David J.; Marmorstein, Ronen; Mahadevan, Louis C.; Alani, Rhoda M.; Cole, Philip A.

    2010-01-01

    Summary The histone acetyltransferase (HAT) p300/CBP is a transcriptional coactivator implicated in many gene regulatory pathways and protein acetylation events. While p300 inhibitors have been reported, a potent, selective, and readily available active-site directed small molecule inhibitor is not yet known. Here we use a structure-based, in silico screening approach to identify a commercially available pyrazolone-containing small molecule p300 HAT inhibitor, C646. C646 is a competitive p300 inhibitor with a Ki of 400 nM and is selective versus other acetyltransferases. Studies on site-directed p300 HAT mutants and synthetic modifications of C646 confirm the importance of predicted interactions in conferring potency. Inhibition of histone acetylation and cell growth by C646 in cells validate its utility as a pharmacologic probe and suggest that p300/CBP HAT is a worthy anti-cancer target. PMID:20534345

  5. A small-molecule inhibitor of sarcomere contractility suppresses hypertrophic cardiomyopathy in mice

    PubMed Central

    Green, Eric M.; Wakimoto, Hiroko; Anderson, Robert L.; Evanchik, Marc J.; Gorham, Joshua M.; Harrison, Brooke C.; Henze, Marcus; Kawas, Raja; Oslob, Johan D.; Rodriguez, Hector M.; Song, Yonghong; Wan, William; Leinwand, Leslie A.; Spudich, James A.; McDowell, Robert S.; Seidman, J. G.; Seidman, Christine E.

    2016-01-01

    Hypertrophic cardiomyopathy (HCM) is an inherited disease of heart muscle that can be caused by mutations in sarcomere proteins. Clinical diagnosis depends on an abnormal thickening of the heart, but the earliest signs of disease are hyperdynamic contraction and impaired relaxation. Whereas some in vitro studies of power generation by mutant and wild-type sarcomere proteins are consistent with mutant sarcomeres exhibiting enhanced contractile power, others are not. We identified a small molecule, MYK-461, that reduces contractility by decreasing the adenosine triphosphatase activity of the cardiac myosin heavy chain. Here we demonstrate that early, chronic administration of MYK-461 suppresses the development of ventricular hypertrophy, cardiomyocyte disarray, and myocardial fibrosis and attenuates hypertrophic and profibrotic gene expression in mice harboring heterozygous human mutations in the myosin heavy chain. These data indicate that hyperdynamic contraction is essential for HCM pathobiology and that inhibitors of sarcomere contraction may be a valuable therapeutic approach for HCM. PMID:26912705

  6. Functional characterization of a SUMO deconjugating protease of Plasmodium falciparum using newly identified small molecule inhibitors

    PubMed Central

    Ponder, Elizabeth L.; Albrow, Victoria E.; Leader, Brittany A.; Békés, Miklós; Mikolajczyk, Jowita; Fonović, Urša Pečar; Shen, Aimee; Drag, Marcin; Xiao, Junpeng; Deu, Edgar; Campbell, Amy J.; Powers, James C.; Salvesen, Guy S.; Bogyo, Matthew

    2011-01-01

    SUMMARY Small ubiquitin-related modifier (SUMO) is implicated in the regulation of numerous biological processes including transcription, protein localization, and cell cycle control. Protein modification by SUMO is found in Plasmodium falciparum; however, its role in the regulation of the parasite lifecycle is poorly understood. Here we describe functional studies of a SUMO-specific protease (SENP) of P. falciparum, PfSENP1 (PFL1635w). Expression of the catalytic domain of PfSENP1 and biochemical profiling using a positional scanning substrate library demonstrated that this protease has unique cleavage sequence preference relative to the human SENPs. In addition, we describe a novel class of small molecule inhibitors of this protease. The most potent lead compound inhibited both recombinant PfSENP1 activity and P. falciparum replication in infected human blood. These studies provide valuable new tools for the study of SUMOylation in P. falciparum. PMID:21700207

  7. Dichotomy of cellular inhibition by small-molecule inhibitors revealed by single-cell analysis

    PubMed Central

    Vogel, Robert M.; Erez, Amir; Altan-Bonnet, Grégoire

    2016-01-01

    Despite progress in drug development, a quantitative and physiological understanding of how small-molecule inhibitors act on cells is lacking. Here, we measure the signalling and proliferative response of individual primary T-lymphocytes to a combination of antigen, cytokine and drug. We uncover two distinct modes of signalling inhibition: digital inhibition (the activated fraction of cells diminishes upon drug treatment, but active cells appear unperturbed), versus analogue inhibition (the activated fraction is unperturbed whereas activation response is diminished). We introduce a computational model of the signalling cascade that accounts for such inhibition dichotomy, and test the model predictions for the phenotypic variability of cellular responses. Finally, we demonstrate that the digital/analogue dichotomy of cellular response as revealed on short (signal transduction) timescales, translates into similar dichotomy on longer (proliferation) timescales. Our single-cell analysis of drug action illustrates the strength of quantitative approaches to translate in vitro pharmacology into functionally relevant cellular settings. PMID:27687249

  8. Identification and Characterization of a Novel Small-Molecule Inhibitor of β-Catenin Signaling

    PubMed Central

    Delgado, Evan R.; Yang, Jing; So, Juhoon; Leimgruber, Stephanie; Kahn, Michael; Ishitani, Tohru; Shin, Donghun; Mustata Wilson, Gabriela; Monga, Satdarshan P.

    2015-01-01

    Hepatocellular carcinoma (HCC), the third most common cause of cancer-related deaths worldwide, lacks effective medical therapy. Large subsets of HCC demonstrate Wnt/β-catenin activation, making this an attractive therapeutic target. We report strategy and characterization of a novel small-molecule inhibitor, ICG-001, known to affect Wnt signaling by disrupting β-catenin–CREB binding protein interactions. We queried the ZINC online database for structural similarity to ICG-001 and identified PMED-1 as the lead compound, with ≥70% similarity to ICG-001. PMED-1 significantly reduced β-catenin activity in hepatoblastoma and several HCC cells, as determined by TOPflash reporter assay, with an IC50 ranging from 4.87 to 32 μmol/L. Although no toxicity was observed in primary human hepatocytes, PMED-1 inhibited Wnt target expression in HCC cells, including those with CTNNB1 mutations, and impaired cell proliferation and viability. PMED-1 treatment decreased β-catenin–CREB binding protein interactions without affecting total β-catenin levels or activity of other common kinases. PMED-1 treatment of Tg(OTM:d2EGFP) zebrafish expressing GFP under the β-catenin/Tcf reporter led to a notable decrease in β-catenin activity. The PMED effect on β-catenin signaling lasted from 12 to 24 hours in vitro and 6 to 15 hours in vivo. Thus, using a rapid and cost-effective computational methodology, we have identified a novel and specific small-molecule inhibitor of Wnt signaling that may have implications for HCC treatment. PMID:24819961

  9. Structure-Function Correlation of G6, a Novel Small Molecule Inhibitor of Jak2

    PubMed Central

    Majumder, Anurima; Govindasamy, Lakshmanan; Magis, Andrew; Kiss, Róbert; Polgár, Tímea; Baskin, Rebekah; Allan, Robert W.; Agbandje-McKenna, Mavis; Reuther, Gary W.; Keserű, György M.; Bisht, Kirpal S.; Sayeski, Peter P.

    2010-01-01

    Somatic mutations in the Jak2 protein, such as V617F, cause aberrant Jak/STAT signaling and can lead to the development of myeloproliferative neoplasms. This discovery has led to the search for small molecule inhibitors that target Jak2. Using structure-based virtual screening, our group recently identified a novel small molecule inhibitor of Jak2 named G6. Here, we identified a structure-function correlation of this compound. Specifically, five derivative compounds of G6 having structural similarity to the original lead compound were obtained and analyzed for their ability to (i) inhibit Jak2-V617F-mediated cell growth, (ii) inhibit the levels of phospho-Jak2, phospho-STAT3, and phospho-STAT5; (iii) induce apoptosis in human erythroleukemia cells; and (iv) suppress pathologic cell growth of Jak2-V617F-expressing human bone marrow cells ex vivo. Additionally, we computationally examined the interactions of these compounds with the ATP-binding pocket of the Jak2 kinase domain. We found that the stilbenoid core-containing derivatives of G6 significantly inhibited Jak2-V617F-mediated cell proliferation in a time- and dose-dependent manner. They also inhibited phosphorylation of Jak2, STAT3, and STAT5 proteins within cells, resulting in higher levels of apoptosis via the intrinsic apoptotic pathway. Finally, the stilbenoid derivatives inhibited the pathologic growth of Jak2-V617F-expressing human bone marrow cells ex vivo. Collectively, our data demonstrate that G6 has a stilbenoid core that is indispensable for maintaining its Jak2 inhibitory potential. PMID:20667821

  10. Quantitative changes in focal adhesion kinase and its inhibitor, FRNK, drive load-dependent expression of costamere components.

    PubMed

    Klossner, Stephan; Li, Ruowei; Ruoss, Severin; Durieux, Anne-Cécile; Flück, Martin

    2013-09-15

    Costameres are mechanosensory sites of focal adhesion in the sarcolemma that reinforce the muscle-fiber composite and provide an anchor for myofibrillogenesis. We hypothesized that elevated content of the integrin-associated regulator of costamere turnover in culture, focal adhesion kinase (FAK), drives changes in costamere component content in antigravity muscle in a load-dependent way in correspondence with altered muscle weight. The content of FAK in soleus muscle being phosphorylated at autoregulatory tyrosine 397 (FAK-pY397) was increased after 20 s of stretch. FAK-pY397 content remained elevated after 24 h of stretch-overload due to upregulated FAK content. Overexpression of FAK in soleus muscle fibers by means of gene electrotransfer increased the β1-integrin (+56%) and meta-vinculin (+88%) content. α7-Integrin (P = 0.46) and γ-vinculin (P = 0.18) content was not altered after FAK overexpression. Co-overexpression of the FAK inhibitor FAK-related nonkinase (FRNK) reduced FAK-pY397 content by 33% and increased the percentage of fast-type fibers that arose in connection with hybrid fibers with gene transfer. Transplantation experiments confirmed the association of FRNK expression with slow-to-fast fiber transformation. Seven days of unloading blunted the elevation of FAK-pY397, β1-integrin, and meta-vinculin content with FAK overexpression, and this was reversed by 1 day of reloading. The results highlight that the expression of components for costameric attachment sites of myofibrils is under load- and fiber type-related control via FAK and its inhibitor FRNK.

  11. Interaction of small molecule inhibitors of HIV-1 entry with CCR5

    SciTech Connect

    Seibert, Christoph . E-mail: seiberc@mail.rockefeller.edu; Ying Weiwen; Gavrilov, Svetlana; Tsamis, Fotini; Kuhmann, Shawn E.; Palani, Anandan; Tagat, Jayaram R.; Clader, John W.; McCombie, Stuart W.; Baroudy, Bahige M.; Smith, Steven O.; Dragic, Tatjana; Moore, John P.; Sakmar, Thomas P.

    2006-05-25

    The CC-chemokine receptor 5 (CCR5) is the major coreceptor for macrophage-tropic (R5) HIV-1 strains. Several small molecule inhibitors of CCR5 that block chemokine binding and HIV-1 entry are being evaluated as drug candidates. Here we define how CCR5 antagonists TAK-779, AD101 (SCH-350581) and SCH-C (SCH-351125), which inhibit HIV-1 entry, interact with CCR5. Using a mutagenesis approach in combination with a viral entry assay to provide a direct functional read out, we tested predictions based on a homology model of CCR5 and analyzed the functions of more than 30 amino acid residues. We find that a key set of aromatic and aliphatic residues serves as a hydrophobic core for the ligand binding pocket, while E283 is critical for high affinity interaction, most likely by acting as the counterion for a positively charged nitrogen atom common to all three inhibitors. These results provide a structural basis for understanding how specific antagonists interact with CCR5, and may be useful for the rational design of new, improved CCR5 ligands.

  12. A Novel, Potent, Small Molecule AKT Inhibitor Exhibits Efficacy against Lung Cancer Cells In Vitro

    PubMed Central

    Dinavahi, Saketh S.; Prasanna, Rajagopalan; Dharmarajan, Sriram; Perumal, Yogeeswari; Viswanadha, Srikant

    2015-01-01

    Purpose Anomalies of Akt regulation, including overexpression in lung cancer, impart resistance to conventional chemotherapy and radiation, thereby implicating this kinase as a therapeutic intervention point. A novel scaffold of Akt inhibitors was developed through virtual screening of chemical databases available at Birla Institute of Technology and Science, Pilani, Hyderabad, based on docking studies using Maestro. A benzothienopyrimidine derivative (BIA-6) was identified as a potential lead molecule that inhibited Akt1 enzyme activity with an IC50 of 256 nM. Materials and Methods BIA-6 was tested for in vitro Akt1 inhibition using a fluorescence resonance energy transfer kit. Anti-proliferative activity was tested in NCI-H460, A549, NCI-H1975, and NCI-H2170 cell lines. The effect of the compound on p-Akt (S473) was estimated. Results BIA-6 allosterically caused a dose dependent reduction of growth of cell lines with a half maximal growth inhibition (GI50) range of 0.49 μM to 6.6 μM. Cell cycle analysis indicated that BIA-6 caused a G1 phase arrest at < 100 nM but led to apoptosis at higher doses. BIA-6 also exhibited synergism with standard chemotherapeutic agents. Conclusion BIA-6 is a novel, allosteric Akt inhibitor with potent anti-cancer activity in lung cancer cell lines, that effectively blocks the phosphoinositide-3 kinase/Akt pathway with a high margin selectivity towards normal cells. PMID:25687876

  13. Targeting BRCA1- and BRCA2-deficient cells with RAD52 small molecule inhibitors.

    PubMed

    Huang, Fei; Goyal, Nadish; Sullivan, Katherine; Hanamshet, Kritika; Patel, Mikir; Mazina, Olga M; Wang, Charles X; An, W Frank; Spoonamore, James; Metkar, Shailesh; Emmitte, Kyle A; Cocklin, Simon; Skorski, Tomasz; Mazin, Alexander V

    2016-05-19

    RAD52 is a member of the homologous recombination (HR) pathway that is important for maintenance of genome integrity. While single RAD52 mutations show no significant phenotype in mammals, their combination with mutations in genes that cause hereditary breast cancer and ovarian cancer like BRCA1, BRCA2, PALB2 and RAD51C are lethal. Consequently, RAD52 may represent an important target for cancer therapy. In vitro, RAD52 has ssDNA annealing and DNA strand exchange activities. Here, to identify small molecule inhibitors of RAD52 we screened a 372,903-compound library using a fluorescence-quenching assay for ssDNA annealing activity of RAD52. The obtained 70 putative inhibitors were further characterized using biochemical and cell-based assays. As a result, we identified compounds that specifically inhibit the biochemical activities of RAD52, suppress growth of BRCA1- and BRCA2-deficient cells and inhibit RAD52-dependent single-strand annealing (SSA) in human cells. We will use these compounds for development of novel cancer therapy and as a probe to study mechanisms of DNA repair. PMID:26873923

  14. Phenylphthalazines as small-molecule inhibitors of urea transporter UT-B and their binding model

    PubMed Central

    Ran, Jian-hua; Li, Min; Tou, Weng-Ieong; Lei, Tian-luo; Zhou, Hong; Chen, Calvin Yu-Chian; Yang, Bao-xue

    2016-01-01

    Aim: Urea transporters (UT) are a family of transmembrane proteins that specifically transport urea. UT inhibitors exert diuretic activity without affecting electrolyte balance. The purpose of this study was to discover novel UT inhibitors and determine the inhibition mechanism. Methods: The primary screening urea transporter B (UT-B) inhibitory activity was conducted in a collection of 10 000 diverse small molecules using mouse erythrocyte lysis assay. After discovering a hit with a core structure of 1-phenylamino-4-phenylphthalazin, the UT-B inhibitory activity of 160 analogs were examined with a stopped-flow light scattering assay and their structure-activity relationship (SAR) was analyzed. The inhibition mechanism was further investigated using in silico assays. Results: A phenylphthalazine compound PU1424, chemically named 5-(4-((4-methoxyphenyl) amino) phthalazin-1-yl)-2-methylbenzene sulfonamide, showed potent UT-B inhibition activity, inhibited human and mouse UT-B-mediated urea transport with IC50 value of 0.02 and 0.69 μmol/L, respectively, and exerted 100% UT-B inhibition at higher concentrations. The compound PU1424 did not affect membrane urea transport in mouse erythrocytes lacking UT-B. Structure-activity analysis revealed that the analogs with methoxyl group at R4 and sulfonic amide at R2 position exhibited the highest potency inhibition activity on UT-B. Furthermore, in silico assays validated that the R4 and R2 positions of the analogs bound to the UT-B binding pocket and exerted inhibition activity on UT-B. Conclusion: The compound PU1424 is a novel inhibitor of both human and mouse UT-B with IC50 at submicromolar ranges. Its binding site is located at the So site of the UT-B structure. PMID:27238209

  15. Cell adhesion molecule CD44: its functional roles in prostate cancer.

    PubMed

    Iczkowski, Kenneth A

    2010-09-12

    CD44 is a cell adhesion glycoprotein that also governs cell signaling. Dysregulated CD44 expression characterizes most human cancers, including prostate cancer (PCa). PCa loses expression of CD44 standard (CD44s) that is present in benign epithelium, and overexpresses the novel splice variant (v) isoform, CD44v7-10. We studied CD44 in PCa for more than a decade, and in a series of papers, established its functional significance. Using retrovi-ral gene delivery to PC-3M PCa cells, we expressed luciferase-only, enforced CD44s re-expression as a fusion protein with luciferase at its C-terminus or as a protein separate from luciferase, or knocked down CD44v7-10 by RNAi. Invasion, migration, proliferation, soft agar colony formation, adhesion, Docetaxel sensitivity, and xenograft growth assays were carried out. Compared to luciferase-only PC-3M cells, all 3 treatments reduced invasion and migration. Growth and soft agar colony formation were reduced only by re-expression of CD44s as a separate or fusion protein but not CD44v7-10 RNAi. Hyaluronan and osteopontin binding were greatly strengthened by CD44s expression as a separate protein, but not a fusion protein. CD44v7-10 RNAi in PC-3M cells caused marked sensitization to Docetaxel; the 2 CD44s re-expression approaches caused minimal sensitization. In limited numbers of mouse subcutaneous xeno-grafts, all 3 alterations produced only nonsignificant trends toward slower growth compared with luciferase-only controls. In further work, we tested the effects of the anti-growth compound silibinin, a milk thistle derivative. Using a luciferase promoter construct to test for CD44 promoter activity, silibinin significantly and dose-dependently inhibited promoter activity at physiologic doses. Total CD44 RNA and CD44v7-10 RNA were significantly decreased; both were also decreased at the protein level. Phenyl-methylene hydantoins (PMH), guanidine alkaloids derived from Red Sea sponges, have the ability to increase cell

  16. Functional analysis of posttranslational cleavage products of the neuron-glia cell adhesion molecule, Ng-CAM

    PubMed Central

    1995-01-01

    Neuron-glia cell adhesion molecule (Ng-CAM) mediates cell adhesion between neurons homophilically and between neurons and glia heterophilically; it also promotes neurite outgrowth. In the chick brain, Ng-CAM is detected as glycoproteins of 190 and 210 kD (Ng- CAM200) with posttranslational cleavage products of 135 kD (F135, which contains most of the extracellular region) and 80 kD (F80, which includes the transmembrane and the cytoplasmic domains). To examine the functions of each of these components, we have expressed Ng-CAM200, F135, and F80 in murine L cells, and F135 and F80 as GST fusion proteins in the pGEX vector in bacteria. Appropriately transfected L cells expressed each of these proteins on their surfaces; F135 was also found in the media of cells transfected with Ng-CAM200 and F135. In addition to binding homophilically, cells transfected with Ng-CAM200 and F135 bound heterophilically to untransfected L cells, suggesting that there is a ligand for Ng-CAM on fibroblasts that may be related to the glial ligand. Detailed studies using the transfected cells and the fusion proteins indicated that both the homophilic and the heterophilic binding activities of Ng-CAM are localized in the F135 fragment of the molecule. The results also indicated that proteolytic cleavage of Ng- CAM200 is not required either for its expression on the cell surface or for cell adhesion and that there is an "anchor" for F135 on L cells (and presumably on neurons). In contrast to the cell binding results, the F80 but not the F135 fusion protein enhanced the outgrowth of neurites from dorsal root ganglion cells; this activity was associated with the FnIII repeats of F80. The observations that a protein corresponding to F135 contains the cell aggregation sites whereas one corresponding to the F80 has the ability to promote neurite outgrowth suggest that proteolytic cleavage may be an important event in regulating these Ng-CAM activities during embryonic development and neural

  17. Structures of Clostridium Botulinum Neurotoxin Serotype A Light Chain Complexed with Small-Molecule Inhibitors Highlight Active-Site Flexibility

    SciTech Connect

    Silvaggi,N.; Boldt, G.; Hixon, M.; Kennedy, J.; Tzipori, S.; Janda, K.; Allen, K.

    2007-01-01

    The potential for the use of Clostridial neurotoxins as bioweapons makes the development of small-molecule inhibitors of these deadly toxins a top priority. Recently, screening of a random hydroxamate library identified a small-molecule inhibitor of C. botulinum Neurotoxin Serotype A Light Chain (BoNT/A-LC), 4-chlorocinnamic hydroxamate, a derivative of which has been shown to have in vivo efficacy in mice and no toxicity. We describe the X-ray crystal structures of BoNT/A-LC in complexes with two potent small-molecule inhibitors. The structures of the enzyme with 4-chlorocinnamic hydroxamate or 2,4-dichlorocinnamic hydroxamate bound are compared to the structure of the enzyme complexed with L-arginine hydroxamate, an inhibitor with modes