Curcuma longa Is Able to Induce Apoptotic Cell Death of Pterygium-Derived Human Keratinocytes

PubMed Central

Sancilio, Silvia; Di Staso, Silvio; Sebastiani, Stefano; Centurione, Lucia; Ciancaglini, Marco

2017-01-01

Pterygium is a relatively common eye disease that can display an aggressive clinical behaviour. To evaluate the in vitro effects of Curcuma longa on human pterygium-derived keratinocytes, specimens of pterygium from 20 patients undergoing pterygium surgical excision were collected. Pterygium explants were put into culture and derived keratinocytes were treated with an alcoholic extract of 1.3% Curcuma longa in 0.001% Benzalkonium Chloride for 3, 6, and 24 h. Cultured cells were examined for CAM5.2 (anti-cytokeratin antibody) and CD140 (anti-fibroblast transmembrane glycoprotein antibody) expression between 3th and 16th passage to assess cell homogeneity. TUNEL technique and Annexin-V/PI staining in flow cytometry were used to detect keratinocyte apoptosis. We showed that Curcuma longa exerts a proapoptotic effect on pterygium-derived keratinocytes already after 3 h treatment. Moreover, after 24 h treatment, Curcuma longa induces a significant increase in TUNEL as well as Annexin-V/PI positive cells in comparison to untreated samples. Our study confirms previous observations highlighting the expression, in pterygium keratinocytes, of nuclear VEGF and gives evidence for the first time to the expression of nuclear and cytoplasmic VEGF-R1. All in all, these findings suggest that Curcuma longa could have some therapeutic potential in the treatment and prevention of human pterygium. PMID:29392130

Curcuma longa Is Able to Induce Apoptotic Cell Death of Pterygium-Derived Human Keratinocytes.

PubMed

Sancilio, Silvia; Di Staso, Silvio; Sebastiani, Stefano; Centurione, Lucia; Di Girolamo, Nick; Ciancaglini, Marco; Di Pietro, Roberta

2017-01-01

Pterygium is a relatively common eye disease that can display an aggressive clinical behaviour. To evaluate the in vitro effects of Curcuma longa on human pterygium-derived keratinocytes, specimens of pterygium from 20 patients undergoing pterygium surgical excision were collected. Pterygium explants were put into culture and derived keratinocytes were treated with an alcoholic extract of 1.3% Curcuma longa in 0.001% Benzalkonium Chloride for 3, 6, and 24 h. Cultured cells were examined for CAM5.2 (anti-cytokeratin antibody) and CD140 (anti-fibroblast transmembrane glycoprotein antibody) expression between 3th and 16th passage to assess cell homogeneity. TUNEL technique and Annexin-V/PI staining in flow cytometry were used to detect keratinocyte apoptosis. We showed that Curcuma longa exerts a proapoptotic effect on pterygium-derived keratinocytes already after 3 h treatment. Moreover, after 24 h treatment, Curcuma longa induces a significant increase in TUNEL as well as Annexin-V/PI positive cells in comparison to untreated samples. Our study confirms previous observations highlighting the expression, in pterygium keratinocytes, of nuclear VEGF and gives evidence for the first time to the expression of nuclear and cytoplasmic VEGF-R1. All in all, these findings suggest that Curcuma longa could have some therapeutic potential in the treatment and prevention of human pterygium.

HIF-1α regulates epithelial inflammation by cell autonomous NFκB activation and paracrine stromal remodeling

PubMed Central

Scortegagna, Marzia; Cataisson, Christophe; Martin, Rebecca J.; Hicklin, Daniel J.; Schreiber, Robert D.; Yuspa, Stuart H.

2008-01-01

Hypoxia inducible factor-1 (HIF-1) is a master regulatory transcription factor controlling multiple cell-autonomous and non–cell-autonomous processes, such as metabolism, angiogenesis, matrix invasion, and cancer metastasis. Here we used a new line of transgenic mice with constitutive gain of HIF-1 function in basal keratinocytes and demonstrated a signaling pathway from HIF-1 to nuclear factor κ B (NFκB) activation to enhanced epithelial chemokine and cytokine elaboration. This pathway was responsible for a phenotypically silent accumulation of stromal inflammatory cells and a marked inflammatory hypersensitivity to a single 12-O-tetradecanoylphorbol-13-acetate (TPA) challenge. HIF-1–induced NFκB activation was composed of 2 elements, IκB hyperphosphorylation and phosphorylation of Ser276 on p65, enhancing p65 nuclear localization and transcriptional activity, respectively. NFκB transcriptional targets macrophage inflammatory protein-2 (MIP-2/CXCL2/3), keratinocyte chemokine (KC/CXCL1), and tumor necrosis factor [alfa] (TNFα) were constitutively up-regulated and further increased after TPA challenge both in cultured keratinocytes and in transgenic mice. Whole animal KC, MIP-2, or TNFα immunodepletion each abrogated TPA-induced inflammation, whereas blockade of either VEGF or placenta growth factor (PlGF) signaling did not affect transgenic inflammatory hyper-responsiveness. Thus, epithelial HIF-1 gain of function remodels the local environment by cell-autonomous NFκB-mediated chemokine and cytokine secretion, which may be another mechanism by which HIF-1 facilitates either inflammatory diseases or malignant progression. PMID:18199827

KC-46A Tanker Modernization (KC-46A)

DTIC Science & Technology

2015-12-01

Selected Acquisition Report ( SAR ) RCS: DD-A&T(Q&A)823-387 KC-46A Tanker Modernization (KC-46A) As of FY 2017 President’s Budget Defense Acquisition...Management Information Retrieval (DAMIR) March 22, 2016 16:45:38 UNCLASSIFIED KC-46A December 2015 SAR March 22, 2016 16:45:38 UNCLASSIFIED 2...Document OSD - Office of the Secretary of Defense O&S - Operating and Support PAUC - Program Acquisition Unit Cost KC-46A December 2015 SAR March 22

KC-130J Transport Aircraft (KC-130J)

DTIC Science & Technology

2015-12-01

Selected Acquisition Report ( SAR ) RCS: DD-A&T(Q&A)823-433 KC-130J Transport Aircraft (KC-130J) As of FY 2017 President’s Budget Defense Acquisition...Management Information Retrieval (DAMIR) March 23, 2016 15:23:28 UNCLASSIFIED KC-130J December 2015 SAR March 23, 2016 15:23:28 UNCLASSIFIED 2...Document OSD - Office of the Secretary of Defense O&S - Operating and Support PAUC - Program Acquisition Unit Cost KC-130J December 2015 SAR March 23

Human Atopic Dermatitis Skin-derived T Cells can Induce a Reaction in Mouse Keratinocytes in vivo.

PubMed

Martel, B C; Blom, L; Dyring-Andersen, B; Skov, L; Thestrup-Pedersen, K; Skov, S; Skak, K; Poulsen, L K

2015-08-01

In atopic dermatitis (AD), the inflammatory response between skin-infiltrating T cells and keratinocytes is fundamental to the development of chronic lesional eczema. The aim of this study was to investigate whether skin-derived T cells from AD patients could induce an inflammatory response in mice through keratinocyte activation and consequently cause the development of eczematous lesions. Punch biopsies of the lesional skin from AD patients were used to establish skin-derived T cell cultures, which were transferred to NOD.Cg-Prkd(scid) Il2rg(tm1Sug) /JicTac (NOG) mice. We found that the subcutaneous injection of the human AD skin-derived T cells resulted in the migration of the human T cells from subcutis to the papillary dermis followed by the development of erythema and oedema in the mouse skin. Furthermore, the human T cells induced a transient proliferative response in the mouse keratinocytes shown as increased numbers of Ki-67(+) keratinocytes and increased epidermal thickness. Out of six established AD skin-derived T cell cultures, two were superior at inducing a skin reaction in the mice, and these cultures were found to contain >10% CCR10(+) T cells compared to <2% for the other cultures. In comparison, blood-derived in vitro-differentiated Th2 cells only induced a weak response in a few of the mice. Thus, we conclude that human AD skin-derived T cells can induce a reaction in the mouse skin through the induction of a proliferative response in the mouse keratinocytes. © 2015 The Foundation for the Scandinavian Journal of Immunology.

Neutrophil-derived chemokines on the road to immunity.

PubMed

Tecchio, Cristina; Cassatella, Marco A

2016-04-01

During recent years, it has become clear that polymorphonuclear neutrophils are remarkably versatile cells, whose functions go far beyond phagocytosis and killing. In fact, besides being involved in primary defense against infections-mainly through phagocytosis, generation of toxic molecules, release of toxic enzymes and formation of extracellular traps-neutrophils have been shown to play a role in finely regulating the development and the evolution of inflammatory and immune responses. These latter neutrophil-mediated functions occur by a variety of mechanisms, including the production of newly manufactured cytokines. Herein, we provide a general overview of the chemotactic cytokines/chemokines that neutrophils can potentially produce, either under inflammatory/immune reactions or during their activation in more prolonged processes, such as in tumors. We highlight recent observations generated from studying human or rodent neutrophils in vitro and in vivo models. We also discuss the biological significance of neutrophil-derived chemokines in the context of infectious, neoplastic and immune-mediated diseases. The picture that is emerging is that, given their capacity to produce and release chemokines, neutrophils exert essential functions in recruiting, activating and modulating the activities of different leukocyte populations. Copyright © 2016. Published by Elsevier Ltd.

Development of a Full-Thickness Human Gingiva Equivalent Constructed from Immortalized Keratinocytes and Fibroblasts.

PubMed

Buskermolen, Jeroen K; Reijnders, Christianne M A; Spiekstra, Sander W; Steinberg, Thorsten; Kleverlaan, Cornelis J; Feilzer, Albert J; Bakker, Astrid D; Gibbs, Susan

2016-08-01

Organotypic models make it possible to investigate the unique properties of oral mucosa in vitro. For gingiva, the use of human primary keratinocytes (KC) and fibroblasts (Fib) is limited due to the availability and size of donor biopsies. The use of physiologically relevant immortalized cell lines would solve these problems. The aim of this study was to develop fully differentiated human gingiva equivalents (GE) constructed entirely from cell lines, to compare them with the primary cell counterpart (Prim), and to test relevance in an in vitro wound healing assay. Reconstructed gingiva epithelium on a gingiva fibroblast-populated collagen hydrogel was constructed from cell lines (keratinocytes: TERT or HPV immortalized; fibroblasts: TERT immortalized) and compared to GE-Prim and native gingiva. GE were characterized by immunohistochemical staining for proliferation (Ki67), epithelial differentiation (K10, K13), and basement membrane (collagen type IV and laminin 5). To test functionality of GE-TERT, full-thickness wounds were introduced. Reepithelialization, fibroblast repopulation of hydrogel, metabolic activity (MTT assay), and (pro-)inflammatory cytokine release (enzyme-linked immunosorbent assay) were assessed during wound closure over 7 days. Significant differences in basal KC cytokine secretion (IL-1α, IL-18, and CXCL8) were only observed between KC-Prim and KC-HPV. When Fib-Prim and Fib-TERT were stimulated with TNF-α, no differences were observed regarding cytokine secretion (IL-6, CXCL8, and CCL2). GE-TERT histology, keratin, and basement membrane protein expression very closely represented native gingiva and GE-Prim. In contrast, the epithelium of GE made with HPV-immortalized KC was disorganized, showing suprabasal proliferating cells, limited keratinocyte differentiation, and the absence of basement membrane proteins. When a wound was introduced into the more physiologically relevant GE-TERT model, an immediate inflammatory response (IL-6, CCL2, and

Development of a Full-Thickness Human Gingiva Equivalent Constructed from Immortalized Keratinocytes and Fibroblasts

PubMed Central

Buskermolen, Jeroen K.; Reijnders, Christianne M.A.; Spiekstra, Sander W.; Steinberg, Thorsten; Kleverlaan, Cornelis J.; Feilzer, Albert J.; Bakker, Astrid D.

2016-01-01

Organotypic models make it possible to investigate the unique properties of oral mucosa in vitro. For gingiva, the use of human primary keratinocytes (KC) and fibroblasts (Fib) is limited due to the availability and size of donor biopsies. The use of physiologically relevant immortalized cell lines would solve these problems. The aim of this study was to develop fully differentiated human gingiva equivalents (GE) constructed entirely from cell lines, to compare them with the primary cell counterpart (Prim), and to test relevance in an in vitro wound healing assay. Reconstructed gingiva epithelium on a gingiva fibroblast-populated collagen hydrogel was constructed from cell lines (keratinocytes: TERT or HPV immortalized; fibroblasts: TERT immortalized) and compared to GE-Prim and native gingiva. GE were characterized by immunohistochemical staining for proliferation (Ki67), epithelial differentiation (K10, K13), and basement membrane (collagen type IV and laminin 5). To test functionality of GE-TERT, full-thickness wounds were introduced. Reepithelialization, fibroblast repopulation of hydrogel, metabolic activity (MTT assay), and (pro-)inflammatory cytokine release (enzyme-linked immunosorbent assay) were assessed during wound closure over 7 days. Significant differences in basal KC cytokine secretion (IL-1α, IL-18, and CXCL8) were only observed between KC-Prim and KC-HPV. When Fib-Prim and Fib-TERT were stimulated with TNF-α, no differences were observed regarding cytokine secretion (IL-6, CXCL8, and CCL2). GE-TERT histology, keratin, and basement membrane protein expression very closely represented native gingiva and GE-Prim. In contrast, the epithelium of GE made with HPV-immortalized KC was disorganized, showing suprabasal proliferating cells, limited keratinocyte differentiation, and the absence of basement membrane proteins. When a wound was introduced into the more physiologically relevant GE-TERT model, an immediate inflammatory response (IL-6, CCL2, and

Inflammatory Cytokine Pattern Is Sex-Dependent in Mouse Cutaneous Melanoma Experimental Model

PubMed Central

Surcel, Mihaela

2017-01-01

We present the evaluation of inflammatory cytokines in mouse cutaneous melanoma experimental model, as markers of disease evolution. Moreover, to test our experimental model, we have used low doses of dacarbazine (DTIC). C57 BL/6J mouse of both sexes were subjected to experimental cutaneous melanoma and treated with low doses of DTIC. Clinical parameters and serum cytokines were followed during tumor evolution and during DTIC therapy. Cytokine/chemokine pattern was assessed using xMAP technology and the following molecules were quantified: interleukins (IL)-1-beta, IL-6, IL-10, IL-12 (p70), interferon (IFN)-gamma, granulocyte macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor (TNF)-alpha, macrophage inflammatory protein (MIP)-1alpha, monocyte chemoattractant protein (MCP-1), and keratinocyte-derived chemokine (KC). Significant differences were found between normal females and males mice, female mice having a statistically higher serum concentration of IL-1-beta compared to male mice, while males have a significantly higher concentration of MIP-1-alpha. During melanoma evolution in the female group, IL-1-beta, MIP-1-alpha, and KC circulatory levels were found 10-fold increased, while other cytokines doubled their values. In the male mice group, only circulatory KC increased 4 times, while IL-1-beta and TNF-alpha doubled their circulatory values. Various serum cytokines correlated with the disease evolution in cutaneous melanoma mouse model. PMID:29318162

Central Nervous System Pathology Progresses Independently of KC and CXCR2 in Globoid-Cell Leukodystrophy

PubMed Central

Reddy, Adarsh S.; Patel, Jigisha R.; Vogler, Carole; Klein, Robyn S.; Sands, Mark S.

2013-01-01

Globoid-cell Leukodystrophy (GLD; Krabbe’s disease) is a rapidly progressing inherited demyelinating disease caused by a deficiency of the lysosomal enzyme Galactosylceramidase (GALC). Deficiency of GALC leads to altered catabolism of galactosylceramide and the cytotoxic lipid, galactosylsphingosine (psychosine). This leads to a rapidly progressive fatal disease with spasticity, cognitive disability and seizures. The murine model of GLD (Twitcher; GALC−/−) lacks the same enzyme and has similar clinical features. The deficiency of GALC leads to oligodendrocyte death, profound neuroinflammation, and the influx of activated macrophages into the CNS. We showed previously that keratinocyte chemoattractant factor (KC) is highly elevated in the CNS of untreated Twitcher mice and significantly decreases after receiving a relatively effective therapy (bone marrow transplantation combined with gene therapy). The action of KC is mediated through the CXCR2 receptor and is a potent chemoattractant for macrophages and microglia. KC is also involved in oligodendrocyte migration and proliferation. Based on the commonalities between the disease presentation and the functions of KC, we hypothesized that KC and/or CXCR2 contribute to the pathogenesis of GLD. Interestingly, the course of the disease is not significantly altered in KC- or CXCR2-deficient Twitcher mice. There is also no alteration in inflammation or demyelination patterns in these mice. Furthermore, transplantation of CXCR2-deficient bone marrow does not alter the progression of the disease as it does in other models of demyelination. This study highlights the role of multiple redundant cytokines and growth factors in the pathogenesis of GLD. PMID:23755134

Comparative study of human-induced pluripotent stem cells derived from bone marrow cells, hair keratinocytes, and skin fibroblasts.

PubMed

Streckfuss-Bömeke, Katrin; Wolf, Frieder; Azizian, Azadeh; Stauske, Michael; Tiburcy, Malte; Wagner, Stefan; Hübscher, Daniela; Dressel, Ralf; Chen, Simin; Jende, Jörg; Wulf, Gerald; Lorenz, Verena; Schön, Michael P; Maier, Lars S; Zimmermann, Wolfram H; Hasenfuss, Gerd; Guan, Kaomei

2013-09-01

Induced pluripotent stem cells (iPSCs) provide a unique opportunity for the generation of patient-specific cells for use in disease modelling, drug screening, and regenerative medicine. The aim of this study was to compare human-induced pluripotent stem cells (hiPSCs) derived from different somatic cell sources regarding their generation efficiency and cardiac differentiation potential, and functionalities of cardiomyocytes. We generated hiPSCs from hair keratinocytes, bone marrow mesenchymal stem cells (MSCs), and skin fibroblasts by using two different virus systems. We show that MSCs and fibroblasts are more easily reprogrammed than keratinocytes. This corresponds to higher methylation levels of minimal promoter regions of the OCT4 and NANOG genes in keratinocytes than in MSCs and fibroblasts. The success rate and reprogramming efficiency was significantly higher by using the STEMCCA system than the OSNL system. All analysed hiPSCs are pluripotent and show phenotypical characteristics similar to human embryonic stem cells. We studied the cardiac differentiation efficiency of generated hiPSC lines (n = 24) and found that MSC-derived hiPSCs exhibited a significantly higher efficiency to spontaneously differentiate into beating cardiomyocytes when compared with keratinocyte-, and fibroblast-derived hiPSCs. There was no significant difference in the functionalities of the cardiomyocytes derived from hiPSCs with different origins, showing the presence of pacemaker-, atrial-, ventricular- and Purkinje-like cardiomyocytes, and exhibiting rhythmic Ca2+ transients and Ca2+ sparks in hiPSC-derived cardiomyocytes. Furthermore, spontaneously and synchronously beating and force-developing engineered heart tissues were generated. Human-induced pluripotent stem cells can be reprogrammed from all three somatic cell types, but with different efficiency. All analysed iPSCs can differentiate into cardiomyocytes, and the functionalities of cardiomyocytes derived from different cell

Paracrine Activity from Adipose-Derived Stem Cells on In Vitro Wound Healing in Human Tympanic Membrane Keratinocytes.

PubMed

Ong, Huan Ting; Redmond, Sharon L; Marano, Robert J; Atlas, Marcus D; von Unge, Magnus; Aabel, Peder; Dilley, Rodney J

2017-03-15

Stem cell therapies for tympanic membrane repair have shown initial experimental success using mesenchymal stem cells in rat models to promote healing; however, the mechanisms providing this benefit are not known. We investigated in vitro the paracrine effects of human adipose-derived stem cells (ADSCs) on wound healing mechanisms for human tympanic membrane-derived keratinocytes (hTM) and immortalized human keratinocytes (HaCaT). ADSC conditioned media (CM ADSC ) were assessed for paracrine activity on keratinocyte proliferation and migration, with hypoxic conditions for ADSC culture used to generate contrasting effects on cytokine gene expression. Keratinocytes cultured in CM ADSC showed a significant increase in cell number compared to serum-free cultures and further significant increases in hypoxic CM ADSC . Assessment of ADSC gene expression on a cytokine array showed a range of wound healing cytokines expressed and under stringent hypoxic and serum-free conditions was upregulated (VEGF A, MMP9, Tissue Factor, PAI-1) or downregulated (CXCL5, CCL7, TNF-α). Several of these may contribute to the activity of conditioned media on the keratinocytes with potential applications in TM perforation repair. VEGFA protein was confirmed by immunoassay to be increased in conditioned media. Together with gene regulation associated with hypoxia in ADSCs, this study has provided several strong leads for a stem cell-derived approach to TM wound healing.

CDIP-2, a synthetic peptide derived from chemokine (C-C motif) ligand 13 (CCL13), ameliorates allergic airway inflammation

PubMed Central

Mendez-Enriquez, E; Melendez, Y; Martinez, F; Baay, G; Huerta-Yepez, S; Gonzalez-Bonilla, C; Fortoul, T I; Soldevila, G; García-Zepeda, E A

2008-01-01

Airway inflammation is characterized by selective recruitment of mononuclear and granulocytic cells. This recruitment is mediated by the action of chemotactic cytokines, such as chemokines. A number of chemokines and their receptors have been identified and proposed as potential therapeutic agents in allergic airway inflammation. One of these chemokines is chemokine (C-C motif) ligand 13 (CCL13), a CC chemokine that has been associated with allergic inflammatory diseases such as asthma and allergic rhinitis. To investigate alternative therapeutic agents to alleviate allergic inflammatory diseases, a number of chemokine-derived synthetic peptides were designed and tested for their ability to modulate in vitro and in vivo chemokine-mediated functions. Our results show that one of these peptides, CDIP-2, displayed antagonist functions in in vitro chemotaxis assays using monocytic cell lines. In addition, we found that CDIP-2 significantly reduced peribronchial, perivascular infiltrate and mucus overproduction in an ovalbumin-induced allergic lung inflammation murine model. Thus, CDIP-2 may be considered as part of a novel group of anti-inflammatory agents based on chemokine-derived synthetic peptides. PMID:18336592

CDIP-2, a synthetic peptide derived from chemokine (C-C motif) ligand 13 (CCL13), ameliorates allergic airway inflammation.

PubMed

Mendez-Enriquez, E; Melendez, Y; Martinez, F; Baay, G; Huerta-Yepez, S; Gonzalez-Bonilla, C; Fortoul, T I; Soldevila, G; García-Zepeda, E A

2008-05-01

Airway inflammation is characterized by selective recruitment of mononuclear and granulocytic cells. This recruitment is mediated by the action of chemotactic cytokines, such as chemokines. A number of chemokines and their receptors have been identified and proposed as potential therapeutic agents in allergic airway inflammation. One of these chemokines is chemokine (C-C motif) ligand 13 (CCL13), a CC chemokine that has been associated with allergic inflammatory diseases such as asthma and allergic rhinitis. To investigate alternative therapeutic agents to alleviate allergic inflammatory diseases, a number of chemokine-derived synthetic peptides were designed and tested for their ability to modulate in vitro and in vivo chemokine-mediated functions. Our results show that one of these peptides, CDIP-2, displayed antagonist functions in in vitro chemotaxis assays using monocytic cell lines. In addition, we found that CDIP-2 significantly reduced peribronchial, perivascular infiltrate and mucus overproduction in an ovalbumin-induced allergic lung inflammation murine model. Thus, CDIP-2 may be considered as part of a novel group of anti-inflammatory agents based on chemokine-derived synthetic peptides.

IL-33 promotes mouse keratinocyte-derived chemokine, an IL-8 homologue, expression in airway smooth muscle cells in ovalbumin-sensitized mice.

PubMed

Wu, Wei; Xu, Yuzhu; He, Xinliang; Lu, Yan; Guo, Yali; Yin, Zhuoran; Xie, Jungang; Zhao, Jianping

2014-12-01

Although it is recognized that IL-33 plays a key role in the onset of asthma, it is currently unclear whether IL-33 acts on any other target cells besides mast cells and Th2 cells in asthma. We investigated that whether airway smooth muscle cells (ASMCs) could contribute to asthma via stimulation with IL-33. To create a mouse model of acute asthma, murine ASMCs were isolated and cultured in vitro with IL-33. The ASMCs were divided into two groups, ASMCs from normal mice and ASMCs from ovalbumin-sensitized mice. The release of mouse KC was analyzed by PCR and ELISA. Immunocytochemical Staining of murine ASMCs for ST2 and IL-1RAcP was performed. IL-33 promoted KC expression, both in terms of mRNA and protien levels, in ASMCs from ovalbumin-sensitized mice. ST2 and IL-1RAcP were expressed in the membrane of ASMCs in ovalbumin-sensitized mice. IL-33 may contribute to the inflammation in the airways by acting on airway smooth muscle cells. IL-33 and ST2 may play important roles in allergic bronchial asthma.

The chemokine receptor CXCR6 contributes to recruitment of bone marrow-derived fibroblast precursors in renal fibrosis.

PubMed

Xia, Yunfeng; Yan, Jingyin; Jin, Xiaogao; Entman, Mark L; Wang, Yanlin

2014-08-01

Bone marrow-derived fibroblasts in circulation are of hematopoietic origin, and they proliferate, differentiate into myofibroblasts, and express the chemokine receptor CXCR6. As chemokines mediate the trafficking of circulating cells to sites of injury, we studied the role of CXCR6 in mouse models of renal injury. Significantly, the kidney of CXCR6 knockout mice accumulated fewer bone marrow-derived fibroblasts in response to injury, expressed less profibrotic chemokines and cytokines, displayed fewer myofibroblasts, and expressed less α-smooth muscle actin in the obstructed kidneys compared with wild-type (WT) mice. CXCR6 deficiency inhibited total collagen deposition and suppressed the expression of collagen I and fibronectin in the obstructed kidneys. Furthermore, WT mice engrafted with CXCR6(-/-) bone marrow cells displayed fewer bone marrow-derived fibroblasts in the kidneys with obstructive injury and showed less severe renal fibrosis compared with WT mice engrafted with CXCR6(+/+) bone marrow cells. Transplant of WT bone marrow into CXCR6(-/-) recipients restored recruitment of myeloid fibroblasts and susceptibility to fibrosis. Hematopoietic fibroblasts migrate into injured kidney and proliferate and differentiate into myofibroblasts. Thus, CXCR6, together with other chemokines and their receptors, may have important roles in the recruitment of bone marrow-derived fibroblast precursors into the kidney and contribute to the pathogenesis of renal fibrosis.

The chemokine receptor CXCR6 contributes to recruitment of bone marrow-derived fibroblast precursors in renal fibrosis

PubMed Central

Xia, Yunfeng; Yan, Jingyin; Jin, Xiaogao; Entman, Mark L.; Wang, Yanlin

2014-01-01

Bone marrow-derived fibroblasts in circulation are of hematopoietic origin, proliferate, differentiate into myofibroblasts, and express the chemokine receptor CXCR6. Since chemokines mediate the trafficking of circulating cells to sites of injury, we studied the role of CXCR6 in mouse models of renal injury. Significantly fewer bone marrow-derived fibroblasts accumulated in the kidney of CXCR6 knockout mice in response to injury, expressed less profibrotic chemokines and cytokines, displayed fewer myofibroblasts, and expressed less α-smooth muscle actin in the obstructed kidneys compared with wild-type mice. CXCR6 deficiency inhibited total collagen deposition and suppressed expression of collagen I and fibronectin in the obstructed kidneys. Furthermore, wild type mice engrafted with CXCR6−/− bone marrow cells displayed fewer bone marrow-derived fibroblasts in the kidneys with obstructive injury and showed less severe renal fibrosis compared with wild-type mice engrafted with CXCR6+/+ bone marrow cells. Transplant of wild type bone marrow into CXCR6−/− recipients restored recruitment of myeloid fibroblasts and susceptibility to fibrosis. Hematopoietic fibroblasts migrate into injured kidney and proliferate and differentiate into myofibroblasts. Thus, CXCR6, together with other chemokines and their receptors, may play important roles in the recruitment of bone marrow-derived fibroblast precursors into the kidney and contribute to the pathogenesis of renal fibrosis. PMID:24646857

A CCL chemokine-derived peptide (CDIP-2) exerts anti-inflammatory activity via CCR1, CCR2 and CCR3 chemokine receptors: Implications as a potential therapeutic treatment of asthma.

PubMed

Méndez-Enríquez, E; Medina-Tamayo, J; Soldevila, G; Fortoul, T I; Anton, B; Flores-Romo, L; García-Zepeda, E A

2014-05-01

Allergic asthma is a chronic inflammatory disease characterized by the accumulation of eosinophils, Th2 cells and mononuclear cells in the airways, leading to changes in lung architecture and subsequently reduced respiratory function. We have previously demonstrated that CDIP-2, a chemokine derived peptide, reduced in vitro chemotaxis and decreased cellular infiltration in a murine model of allergic airway inflammation. However, the mechanisms involved in this process have not been identified yet. Now, we found that CDIP-2 reduces chemokine-mediated functions via interactions with CCR1, CCR2 and CCR3. Moreover, using bone marrow-derived eosinophils, we demonstrated that CDIP-2 modifies the calcium fluxes induced by CCL11 and down-modulated CCR3 expression. Finally, CDIP-2 treatment in a murine model of OVA-induced allergic airway inflammation reduced leukocyte recruitment and decreases production of cytokines. These data suggest that chemokine-derived peptides represent new therapeutic tools to generate more effective antiinflammatory drugs. Copyright © 2014 Elsevier B.V. All rights reserved.

Oxidative stress drives CD8+ T-cell skin trafficking in patients with vitiligo through CXCL16 upregulation by activating the unfolded protein response in keratinocytes.

PubMed

Li, Shuli; Zhu, Guannan; Yang, Yuqi; Jian, Zhe; Guo, Sen; Dai, Wei; Shi, Qiong; Ge, Rui; Ma, Jingjing; Liu, Ling; Li, Kai; Luan, Qi; Wang, Gang; Gao, Tianwen; Li, Chunying

2017-07-01

In patients with vitiligo, an increased reactive oxygen species (ROS) level has been proved to be a key player during disease initiation and progression in melanocytes. Nevertheless, little is known about the effects of ROS on other cells involved in the aberrant microenvironment, such as keratinocytes and the following immune events. CXCL16 is constitutively expressed in keratinocytes and was recently found to mediate homing of CD8 + T cells in human skin. We sought to explicate the effect of oxidative stress on human keratinocytes and its capacity to drive CD8 + T-cell trafficking through CXCL16 regulation. We first detected putative T-cell skin-homing chemokines and ROS in serum and lesions of patients with vitiligo. The production of candidate chemokines was detected by using quantitative real-time PCR and ELISA in keratinocytes exposed to H 2 O 2 . Furthermore, the involved mediators were analyzed by using quantitative real-time PCR, Western blotting, ELISA, and immunofluorescence. Next, we tested the chemotactic migration of CD8 + T cells from patients with vitiligo mediated by the CXCL16-CXCR6 pair using the transwell assay. CXCL16 expression increased and showed a positive correlation with oxidative stress levels in serum and lesions of patients with vitiligo. The H 2 O 2 -induced CXCL16 expression was due to the activation of 2 unfolded protein response pathways: kinase RNA (PKR)-like ER kinase-eukaryotic initiation factor 2α and inositol-requiring enzyme 1α-X-box binding protein 1. CXCL16 produced by stressed keratinocytes induced migration of CXCR6 + CD8 + T cells derived from patients with vitiligo. CXCR6 + CD8 + T-cell skin infiltration is accompanied by melanocyte loss in lesions of patients with vitiligo. Our study demonstrated that CXCL16-CXCR6 mediates CD8 + T-cell skin trafficking under oxidative stress in patients with vitiligo. The CXCL16 expression in human keratinocytes induced by ROS is, at least in part, caused by unfolded protein response

SOCS3 inhibits the pathological effects of IL-22 in non-melanoma skin tumor-derived keratinocytes

PubMed Central

Madonna, Stefania; Scarponi, Claudia; Morelli, Martina; Sestito, Rosanna; Scognamiglio, Pasqualina Liana; Marasco, Daniela; Albanesi, Cristina

2017-01-01

Basal cell carcinomas (BCC) and squamous-cell carcinomas (SCC) are common malignancies in humans, caused by neoplastic transformation of keratinocytes of the basal or suprabasal layers of epidermis, respectively. Tumor-infiltrating lymphocytes (TILs) are frequently found in BCC and SCC, and functionally promote epithelial carcinogenesis. TILs secreting IL-22, in particular, participate to BCC and SCC growth by inducing keratinocyte proliferation and migration, as well as the expression of inflammatory, anti-apoptotic and pro-angiogenic genes. In this study, we identified SOCS3 as a valid candidate to be manipulated for suppressing tumorigenic functions in BCC and SCC. We found that SOCS3 and SOCS1 expression was reduced in vivo, in tumor lesions of BCC and SCC, as compared to other skin inflammatory conditions such as psoriasis, despite the high number of IL-22-secreting TILs. Moreover, IL-22 was not able to induce in vitro the transcriptional expression of SOCS3 in BCC-or SCC-derived keratinocytes, contrarily to healthy cells. Aimed at rescuing SOCS3 activity in these tumor contexts, a SOCS3-derived peptide, named KIR-ESS, was synthesized, and its ability in suppressing IL-22-induced responses was evaluated in healthy and transformed keratinocytes. We found that KIR-ESS peptide efficiently suppressed the IL-22 molecular signaling in keratinocytes, by acting on STAT3 and Erk1/2 cascade, as well as on the expression of STAT3-dependent downstream genes. Interestingly, after treatment with peptide, both healthy and transformed keratinocytes could no longer aberrantly proliferate and migrate in response to IL-22. Finally, treatment of athymic nude mice bearing SCC xenografts with KIR-ESS peptide concomitantly reduced tumor growth and activated STAT3 levels. As a whole, these data provides the rationale for the use in BCC and SCC skin tumors of SOCS3 mimetics, being able to inhibit the deleterious effects of IL-22 in these contexts. PMID:28445952

SOCS3 inhibits the pathological effects of IL-22 in non-melanoma skin tumor-derived keratinocytes.

PubMed

Madonna, Stefania; Scarponi, Claudia; Morelli, Martina; Sestito, Rosanna; Scognamiglio, Pasqualina Liana; Marasco, Daniela; Albanesi, Cristina

2017-04-11

Basal cell carcinomas (BCC) and squamous-cell carcinomas (SCC) are common malignancies in humans, caused by neoplastic transformation of keratinocytes of the basal or suprabasal layers of epidermis, respectively. Tumor-infiltrating lymphocytes (TILs) are frequently found in BCC and SCC, and functionally promote epithelial carcinogenesis. TILs secreting IL-22, in particular, participate to BCC and SCC growth by inducing keratinocyte proliferation and migration, as well as the expression of inflammatory, anti-apoptotic and pro-angiogenic genes.In this study, we identified SOCS3 as a valid candidate to be manipulated for suppressing tumorigenic functions in BCC and SCC. We found that SOCS3 and SOCS1 expression was reduced in vivo, in tumor lesions of BCC and SCC, as compared to other skin inflammatory conditions such as psoriasis, despite the high number of IL-22-secreting TILs. Moreover, IL-22 was not able to induce in vitro the transcriptional expression of SOCS3 in BCC-or SCC-derived keratinocytes, contrarily to healthy cells. Aimed at rescuing SOCS3 activity in these tumor contexts, a SOCS3-derived peptide, named KIR-ESS, was synthesized, and its ability in suppressing IL-22-induced responses was evaluated in healthy and transformed keratinocytes. We found that KIR-ESS peptide efficiently suppressed the IL-22 molecular signaling in keratinocytes, by acting on STAT3 and Erk1/2 cascade, as well as on the expression of STAT3-dependent downstream genes. Interestingly, after treatment with peptide, both healthy and transformed keratinocytes could no longer aberrantly proliferate and migrate in response to IL-22. Finally, treatment of athymic nude mice bearing SCC xenografts with KIR-ESS peptide concomitantly reduced tumor growth and activated STAT3 levels. As a whole, these data provides the rationale for the use in BCC and SCC skin tumors of SOCS3 mimetics, being able to inhibit the deleterious effects of IL-22 in these contexts.

Platelet-derived chemokines CXC chemokine ligand (CXCL)7, connective tissue-activating peptide III, and CXCL4 differentially affect and cross-regulate neutrophil adhesion and transendothelial migration.

PubMed

Schenk, Birgit I; Petersen, Frank; Flad, Hans-Dieter; Brandt, Ernst

2002-09-01

In this study, we have examined the major platelet-derived CXC chemokines connective tissue-activating peptide III (CTAP-III), its truncation product neutrophil-activating peptide 2 (CXC chemokine ligand 7 (CXCL7)), as well as the structurally related platelet factor 4 (CXCL4) for their impact on neutrophil adhesion to and transmigration through unstimulated vascular endothelium. Using monolayers of cultured HUVEC, we found all three chemokines to promote neutrophil adhesion, while only CXCL7 induced transmigration. Induction of cell adhesion following exposure to CTAP-III, a molecule to date described to lack neutrophil-stimulating capacity, depended on proteolytical conversion of the inactive chemokine into CXCL7 by neutrophils. This was evident from experiments in which inhibition of the CTAP-III-processing protease and simultaneous blockade of the CXCL7 high affinity receptor CXCR-2 led to complete abrogation of CTAP-III-mediated neutrophil adhesion. CXCL4 at substimulatory dosages modulated CTAP-III- as well as CXCL7-induced adhesion. Although cell adhesion following exposure to CTAP-III was drastically reduced, CXCL7-mediated adhesion underwent significant enhancement. Transendothelial migration of neutrophils in response to CXCL7 or IL-8 (CXCL8) was subject to modulation by CTAP-III, but not CXCL4, as seen by drastic desensitization of the migratory response of neutrophils pre-exposed to CTAP-III, which was paralleled by selective down-modulation of CXCR-2. Altogether our results demonstrate that there exist multiple interactions between platelet-derived chemokines in the regulation of neutrophil adhesion and transendothelial migration.

Modulation of keratinocyte motility. Correlation with production of extracellular matrix molecules in response to growth promoting and antiproliferative factors.

PubMed Central

Nickoloff, B. J.; Mitra, R. S.; Riser, B. L.; Dixit, V. M.; Varani, J.

1988-01-01

Normal human epidermal keratinocytes (KC) grown under conditions that maintain the undifferentiated state are highly motile. Migration of these cells as measured in two different assays (migration out of an agarose drop explant, and into micropore filters in a modified Boyden chamber), is stimulated by fibronectin (FN) and to a lesser extent by thrombospondin (TSP). In contrast, laminin (LN) inhibits KC migration. Cultivation of the cells for 1 day under conditions that induce differentiation (ie, in the presence of 1.4 mM Ca2+) suppresses KC motility. A number of soluble growth modulating polypeptide factors also influence KC migration. Transforming growth factor-beta (TGF-beta) and epidermal growth factor (EGF) stimulate KC motility. These factors simultaneously induce KC production of FN and a significant portion of the stimulated motility can be inhibited with antibodies to FN. EGF and somatomedin-C (SM-C), but not TGF-beta, also stimulate TSP production while EGF and SM-C (but not TGF-beta) induce KC proliferation. In contrast to these factors, interferon-gamma (INF-gamma) inhibits KC production of both FN and TSP and concomitantly inhibits both motility and proliferation. These data suggest that KC properties essential for normal wound healing (ie, motility and proliferation) are regulated by both extracellular matrix molecules and soluble peptide factors. Finally, these effects of various growth promoting and antiproliferative factors on KCs may, in part, be mediated through alteration in the endogenous production of extracellular matrix molecules by KCs. Images Figure 2 PMID:2458044

Studies on acute toxic effects to keratinocytes induced by hematoporphyrin derivatives and laser light.

PubMed

Artuc, M; Ramshad, M; Kappus, H

1989-01-01

Human epidermal keratinocytes were grown in culture and the uptake of hematoporphyrin derivatives (HPDs) used in photodynamic therapy was estimated. Keratinocytes loaded with HPDs were irradiated with laser light of 632 nm generated by a helium-neon laser and cell toxicity was determined by the trypan blue exclusion test and the measurement of enzyme release. With increasing intracellular concentration of HPDs and with increasing intensity of the laser light, an increasing number of cells took up trypan blue and released the cytosolic enzyme lactate dehydrogenase and the lysosomal enzyme acid phosphatase after 1 h incubation of the irradiated cells at 37 degrees C. Cytotoxicity was less pronounced when the irradiated cells were incubated at 0 degree C indicating the involvement of enzyme reactions in cell death. No lipid peroxidation as measured by malondialdehyde and ethane formation was detectable. Our results suggest that during photodynamic therapy with HPDs and laser light epidermal keratinocytes may be seriously damaged. The data indicate that not lipid peroxidation but rather the activation of lysosomal enzymes is responsible for the cytotoxicity observed.

Assessment of spatially distributed values of Kc using vegetation indices derived from medium resolution satellite data

NASA Astrophysics Data System (ADS)

Greco, M.; Simoniello, T.; Lanfredi, M.; Russo, A. L.

2010-09-01

In the last years, the theme of suitable assessment of irrigation water supply has been raised relevant interest for both general principles of sustainable development and optimization of water resources techniques and management. About 99% of the water used in agriculture is lost by crops as evapotranspiration (ET). Thus, it becomes crucial to drive direct or indirect measurement in order to perform a suitable evaluation of water loss by evapotranspiration (i.e. actual evapotranspiration) as well as crop water status and its effect on the production. The main methods used to measure evapotranspiration are available only at field scale (Bowen ratio, eddy correlation system, soil water balance) confined to a small pilot area, generally due to expense and logistical constraints. This led over the last 50 years to the development of a large number of empirical methods to estimate evapotranspiration through different climatic and meteorological variables as well as combining models, based on aerodynamic theory and energy balance, taking into account both canopy properties and meteorological conditions. Among these, the Penman-Monteith equation seems to give the best results providing a robust and consistent method world wide accepted. Such conventional methods only provide accurate evapotranspiration assessment for a homogeneous region nearby the meteorological gauge station and cannot be extrapolated to other different sites; whereas remote sensing techniques allow for filling up such a gap. Some of these satellite techniques are based on the use of thermal band signals as inputs for energy balance equations. Another common approach is mainly based on the FAO method for estimating crop evapotranspiration, in which evapotranspiration data are multiplied by crop coefficients, Kc, derived from satellite multispectral vegetation indices obtained. The rationale behind such a link considers that Kc and vegetation indices are sensitive to both leaf area index and fractional

AV119, a natural sugar from avocado gratissima, modulates the LPS-induced proinflammatory response in human keratinocytes.

PubMed

Donnarumma, Giovanna; Paoletti, Iole; Buommino, Elisabetta; Fusco, Alessandra; Baudouin, Caroline; Msika, Philippe; Tufano, Maria Antonietta; Baroni, Adone

2011-12-01

Keratinocytes play an active role in innate immune responses by secreting a variety of cytokines and chemokines. The release of critical proinflammatory cytokines, which are necessary to activate the immune response, is induced by the stimulation of Toll-like receptors (TLRs) by molecules present on pathogenic micro-organisms such as lipopolysaccharide (LPS). AV119, a patented blend of avocado sugars, induced the aggregation of Malassezia furfur, a dimorphic, lipid-dependent yeast that is part of the normal human cutaneous commensal flora and inhibited its penetration into the keratinocytes. In the present study, the anti-inflammatory effects of AV119 were investigated in LPS-induced inflammation of human keratinocytes. In particular, we analysed the modulation of the LPS-induced expression of proinflammatory cytokines and heat shock protein 70 (HSP70) by AV119 and the involvement of TLR-4. Our data show that AV119 is able to modulate significantly the proinflammatory response in human keratinocytes, blocking the NF-kB activation in human keratinocytes.

Platelet-Derived CCL5 Regulates CXC Chemokine Formation and Neutrophil Recruitment in Acute Experimental Colitis.

PubMed

Yu, Changhui; Zhang, Songen; Wang, Yongzhi; Zhang, Su; Luo, Lingtao; Thorlacius, Henrik

2016-02-01

Accumulating data suggest that platelets not only regulate thrombosis and haemostasis but also inflammatory processes. Platelets contain numerous potent pro-inflammatory compounds, including the chemokines CCL5 and CXCL4, although their role in acute colitis remains elusive. The aim of this study is to examine the role of platelets and platelet-derived chemokines in acute colitis. Acute colitis is induced in female Balb/c mice by administration of 5% dextran sodium sulfate (DSS) for 5 days. Animals receive a platelet-depleting, anti-CCL5, anti-CXCL4, or a control antibody prior to DSS challenge. Colonic tissue is collected for quantification of myeloperoxidase (MPO) activity, CXCL5, CXCL2, interleukin-6 (IL-6), and CCL5 levels as well as morphological analyses. Platelet depletion reduce tissue damage and clinical disease activity index in DSS-exposed animals. Platelet depletion not only reduces levels of CXCL2 and CXCL5 but also levels of CCL5 in the inflamed colon. Immunoneutralization of CCL5 but not CXCL4 reduces tissue damage, CXC chemokine expression, and neutrophil recruitment in DSS-treated animals. These findings show that platelets play a key role in acute colitis by regulating CXC chemokine generation, neutrophil infiltration, and tissue damage in the colon. Moreover, our results suggest that platelet-derived CCL5 is an important link between platelet activation and neutrophil recruitment in acute colitis. © 2015 Wiley Periodicals, Inc.

Application of Recursive Partitioning to Derive and Validate a Claims-Based Algorithm for Identifying Keratinocyte Carcinoma (Nonmelanoma Skin Cancer).

PubMed

Chan, An-Wen; Fung, Kinwah; Tran, Jennifer M; Kitchen, Jessica; Austin, Peter C; Weinstock, Martin A; Rochon, Paula A

2016-10-01

Keratinocyte carcinoma (nonmelanoma skin cancer) accounts for substantial burden in terms of high incidence and health care costs but is excluded by most cancer registries in North America. Administrative health insurance claims databases offer an opportunity to identify these cancers using diagnosis and procedural codes submitted for reimbursement purposes. To apply recursive partitioning to derive and validate a claims-based algorithm for identifying keratinocyte carcinoma with high sensitivity and specificity. Retrospective study using population-based administrative databases linked to 602 371 pathology episodes from a community laboratory for adults residing in Ontario, Canada, from January 1, 1992, to December 31, 2009. The final analysis was completed in January 2016. We used recursive partitioning (classification trees) to derive an algorithm based on health insurance claims. The performance of the derived algorithm was compared with 5 prespecified algorithms and validated using an independent academic hospital clinic data set of 2082 patients seen in May and June 2011. Sensitivity, specificity, positive predictive value, and negative predictive value using the histopathological diagnosis as the criterion standard. We aimed to achieve maximal specificity, while maintaining greater than 80% sensitivity. Among 602 371 pathology episodes, 131 562 (21.8%) had a diagnosis of keratinocyte carcinoma. Our final derived algorithm outperformed the 5 simple prespecified algorithms and performed well in both community and hospital data sets in terms of sensitivity (82.6% and 84.9%, respectively), specificity (93.0% and 99.0%, respectively), positive predictive value (76.7% and 69.2%, respectively), and negative predictive value (95.0% and 99.6%, respectively). Algorithm performance did not vary substantially during the 18-year period. This algorithm offers a reliable mechanism for ascertaining keratinocyte carcinoma for epidemiological research in the absence of

The Effect of Secretory Factors of Adipose-Derived Stem Cells on Human Keratinocytes

PubMed Central

Moon, Kyoung Mi; Park, Ye-Hyoung; Lee, Jae Seol; Chae, Yong-Byung; Kim, Moon-Moo; Kim, Dong-Soo; Kim, Byung-Woo; Nam, Soo-Wan; Lee, Jong-Hwan

2012-01-01

The beneficial effects of adipose-derived stem cell conditioned medium (ADSC-CM) on skin regeneration have been reported. Although the mechanism of how ADSC-CM promotes skin regeneration is unclear, ADSC-CM contained various growth factors and it is an excellent raw material for skin treatment. ADSC-CM produced in a hypoxia condition of ADSC—in other words, Advanced Adipose-Derived Stem cell Protein Extract (AAPE)—has great merits for skin regeneration. In this study, human primary keratinocytes (HKs), which play fundamental roles in skin tissue, was used to examine how AAPE affects HK. HK proliferation was significantly higher in the experimental group (1.22 μg/mL) than in the control group. DNA gene chip demonstrated that AAPE in keratinocytes (p < 0.05) notably affected expression of 290 identified transcripts, which were associated with cell proliferation, cycle and migration. More keratinocyte wound healing and migration was shown in the experimental group (1.22 μg/mL). AAPE treatment significantly stimulated stress fiber formation, which was linked to the RhoA-ROCK pathway. We identified 48 protein spots in 2-D gel analysis and selected proteins were divided into 64% collagen components and 30% non-collagen components as shown by the MALDI-TOF analysis. Antibody array results contained growth factor/cytokine such as HGF, FGF-1, G-CSF, GM-CSF, IL-6, VEGF, and TGF-β3 differing from that shown by 2-D analysis. Conclusion: AAPE activates HK proliferation and migration. These results highlight the potential of the topical application of AAPE in the treatment of skin regeneration. PMID:22312315

TCDD induces dermal accumulation of keratinocyte-derived matrix metalloproteinase-10 in an organotypic model of human skin

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

De Abrew, K. Nadira; Thomas-Virnig, Christina L.; Rasmussen, Cathy A.

2014-05-01

The epidermis of skin is the first line of defense against the environment. A three dimensional model of human skin was used to investigate tissue-specific phenotypes induced by the environmental contaminant, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Continuous treatment of organotypic cultures of human keratinocytes with TCDD resulted in intracellular spaces between keratinocytes of the basal and immediately suprabasal layers as well as thinning of the basement membrane, in addition to the previously reported hyperkeratinization. These tissue remodeling events were preceded temporally by changes in expression of the extracellular matrix degrading enzyme, matrix metalloproteinase-10 (MMP-10). In organotypic cultures MMP-10 mRNA and protein were highlymore » induced following TCDD treatment. Q-PCR and immunoblot results from TCDD-treated monolayer cultures, as well as indirect immunofluorescence and immunoblot analysis of TCDD-treated organotypic cultures, showed that MMP-10 was specifically contributed by the epidermal keratinocytes but not the dermal fibroblasts. Keratinocyte-derived MMP-10 protein accumulated over time in the dermal compartment of organotypic cultures. TCDD-induced epidermal phenotypes in organotypic cultures were attenuated by the keratinocyte-specific expression of tissue inhibitor of metalloproteinase-1, a known inhibitor of MMP-10. These studies suggest that MMP-10 and possibly other MMP-10-activated MMPs are responsible for the phenotypes exhibited in the basement membrane, the basal keratinocyte layer, and the cornified layer of TCDD-treated organotypic cultures. Our studies reveal a novel mechanism by which the epithelial–stromal microenvironment is altered in a tissue-specific manner thereby inducing structural and functional pathology in the interfollicular epidermis of human skin. - Highlights: • TCDD causes hyperkeratosis and basement membrane changes in a model of human skin. • TCDD induces MMP-10 expression in organotypic

Establishment of an Immortalized Skin Keratinocyte Cell Line Derived from the Animal Model Mastomys coucha.

PubMed

Hasche, Daniel; Stephan, Sonja; Savelyeva, Larissa; Westermann, Frank; Rösl, Frank; Vinzón, Sabrina E

2016-01-01

In the present report we describe the establishment of a spontaneous immortalized skin keratinocyte cell line derived from the skin of the multimammate rodent Mastomys coucha. These animals are used in preclinical studies for a variety of human diseases such as infections with nematodes, bacteria and papillomaviruses, especially regarding cutaneous manifestations such as non-melanoma skin cancer. Here we characterize the cells in terms of their origin and cytogenetic features. Searching for genomic signatures, a spontaneous mutation in the splicing donor sequence of Trp53 (G to A transition at the first position of intron 7) could be detected. This point mutation leads to alternative splicing and to a premature stop codon, resulting in a truncated and, in turn, undetectable form of p53, probably contributing to the process of immortalization. Mastomys coucha-derived skin keratinocytes can be used as an in vitro system to investigate molecular and immunological aspects of infectious agent interactions with their host cells.

Circulating Cytokine/Chemokine Concentrations Respond to Ionizing Radiation Doses but not Radiation Dose Rates: Granulocyte-Colony Stimulating Factor and Interleukin-18.

PubMed

Kiang, Juliann G; Smith, Joan T; Hegge, Sara R; Ossetrova, Natalia I

2018-06-01

Exposure to ionizing radiation is a crucial life-threatening factor in nuclear and radiological incidents. It is known that ionizing radiation affects cytokine/chemokine concentrations in the blood of B6D2F1 mice. It is not clear whether radiation dose rates would vary the physiological response. Therefore, in this study we utilized data from two experiments using B6D2F1 female mice exposed to six different dose rates ranging from low to high rates. In one experiment, mice received a total dose of 8 Gy (LD 0/30 ) of 60 Co gamma radiation at four dose rates: 0.04, 0.15, 0.30 and 0.47 Gy/min. Blood samples from mice were collected at 24 and 48 h postirradiation for cytokine/chemokine measurements, including interleukin (IL)-1β, IL-6, IL-10, keratinocyte cytokine (KC), IL-12p70, IL-15, IL-17A, IL-18, granulocyte-colony stimulating factor (G-CSF), granulocyte macrophage (GM)-CSF, macrophage (M)-CSF, monokine induced by gamma interferon (MIG), tumor necrosis factor (TNF)-α, fibroblast growth factor (FGF)-basic, vascular endothelial growth factor (VEGF) and platelet-derived growth factor basic (PDGF-bb). At 24 h after ionizing irradiation at dose rate of 0.04 Gy/min, significant increases were observed only in G-CSF and M-CSF ( P < 0.05). At 0.15 Gy/min, IL-10, IL-17A, G-CSF and GM-CSF concentrations were increased. At 0.3 Gy/min, IL-15, IL-18, G-CSF, GM-CSF, M-CSF, MCP-1, MIP-2, MIG, FGF-basic, VEGF and PDGF-bb were significantly elevated ( P < 0.05). At 0.47 Gy/min, IL-6, KC, IL-10, MCP-1, G-CSF, GM-CSF and M-CSF were significantly increased. At 48 h postirradiation, all cytokines/chemokines except MCP-1 returned to or were below their baselines, suggesting these increases are transient at LD 0/30 irradiation. Of note, there is a limitation on day 2 because cytokines/chemokines are either at or below their baselines. Other parameters such as fms-like tyrosine kinase receptor-3 ligand (Flt-3 ligand) concentrations and lymphocyte counts, which have proven to be

Personal history of keratinocyte carcinoma is associated with reduced risk of death from invasive melanoma in men.

PubMed

Song, Fengju; Chen, Steven T; Li, Xin; Han, Jiali

2018-05-01

Previous studies have found an increased risk for invasive cutaneous melanoma (CM) among those with a history of keratinocyte carcinoma (KC). The aim of this study was to evaluate the risk of CM death after KC. The study was based on the Health Professionals Follow-up Study. A Cox proportional hazards model was used to examine the hazard ratio (HR) of death due to CM associated with personal history of KC among the entire study population (primary analysis) and among participants with invasive CM (secondary analysis), respectively. We documented a total of 908 participants with invasive CM over a total of 0.7 million person-years of follow-up. Among all participants, the risk for development of either lethal or nonlethal invasive CM increased for those with a history of KC. The risk for death due to melanoma based on KC history was not significantly increased, with an HR of 1.53 (95% confidence interval, 0.95-2.46). In the case-only analysis, those with a history of KC had a significantly lower risk for death due to melanoma than those with no such history (HR, 0.60; 95% confidence interval, 0.35-0.94). Because the population covered by the Health Professionals Follow-up Study consists exclusively of male health professionals, the results of this study may not be extended to the entire population. Personal history of KC is associated with a decreased risk for melanoma-specific death among male patients with invasive CM. Copyright © 2018 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Platelet-derived chemokines in atherogenesis: what's new?

PubMed

Gleissner, Christian A

2012-09-01

Over the past decade, platelets have been demonstrated to have various functions beyond their role in hemostasis. Platelets possess a rich repertoire of chemokines that are stored in their alpha granules and can be released upon activation. The pro-atherogenic effects of activated platelets are most likely mediated by release of these pro-inflammatory mediators that promote recruitment, activation or differentiation of other cell types including endothelial cells and leukocytes. These effects have been excellently reviewed in the past by various authors. The current review will therefore focus on novel findings. A specific focus will be put on CXCL4, on which a lot of new data have been published since 2008. Thus, the effects of CXCL4 on macrophage differentiation have been studied in detail revealing that CXCL4 induces a specific macrophage phenotype. Furthermore, novel data on CXCL4L1, a protein similar to CXCL4 that is probably transcribed from a duplication of the PF4 gene coding for CXCL4, will be discussed. A very interesting study has recently demonstrated that the inhibition of heterophilic chemokine interactions using a specifically designed small molecule can inhibit atherogenesis in Apoe-/- mice, thereby demonstrating the clinical potential of tackling platelet chemokines as therapeutic targets in atherosclerosis. Finally, novel data on CXCL1 and CCL5 will be discussed. Overall, while our understanding of the role of platelet chemokines in atherogenesis has significantly improved over the past years, it seems that there may still be many buried treasures in this field that could improve disease prevention or lead to novel clinical therapies.

Scleroderma keratinocytes promote fibroblast activation independent of transforming growth factor beta.

PubMed

McCoy, Sara S; Reed, Tamra J; Berthier, Celine C; Tsou, Pei-Suen; Liu, Jianhua; Gudjonsson, Johann E; Khanna, Dinesh; Kahlenberg, J Michelle

2017-11-01

SSc is a devastating disease that results in fibrosis of the skin and other organs. Fibroblasts are a key driver of the fibrotic process through deposition of extracellular matrix. The mechanisms by which fibroblasts are induced to become pro-fibrotic remain unclear. Thus, we examined the ability of SSc keratinocytes to promote fibroblast activation and the source of this effect. Keratinocytes were isolated from skin biopsies of 9 lcSSc, 10 dcSSc and 13 control patients. Conditioned media was saved from the cultures. Normal fresh primary fibroblasts were exposed to healthy control and SSc keratinocyte conditioned media in the presence or absence of neutralizing antibodies for TGF-β. Gene expression was assessed by microarrays and real-time PCR. Immunocytochemistry was performed for α-smooth muscle actin (α-SMA), collagen type 1 (COL1A1) and CCL5 expression. SSc keratinocyte conditioned media promoted fibroblast activation, characterized by increased α-SMA and COL1A1 mRNA and protein expression. This effect was independent of TGF-β. Microarray analysis identified upregulation of nuclear factor κB (NF-κB) and downregulation of peroxisome proliferator-activated receptor γ (PPAR-γ) pathways in both SSc subtypes. Scleroderma keratinocytes exhibited increased expression of NF-κB-regulated cytokines and chemokines and lesional skin staining confirmed upregulation of CCL5 in basal keratinocytes. Scleroderma keratinocytes promote the activation of fibroblasts in a TGF-β-independent manner and demonstrate an imbalance in NF-κB1 and PPAR-γ expression leading to increased cytokine and CCL5 production. Further study of keratinocyte mediators of fibrosis, including CCL5, may provide novel targets for skin fibrosis therapy. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Semaphorin4D Drives CD8+ T-Cell Lesional Trafficking in Oral Lichen Planus via CXCL9/CXCL10 Upregulations in Oral Keratinocytes.

PubMed

Ke, Yao; Dang, Erle; Shen, Shengxian; Zhang, Tongmei; Qiao, Hongjiang; Chang, Yuqian; Liu, Qing; Wang, Gang

2017-11-01

Chemokine-mediated CD8 + T-cell recruitment is an essential but not well-established event for the persistence of oral lichen planus (OLP). Semaphorin 4D (Sema4D)/CD100 is implicated in immune dysfunction, chemokine modulation, and cell migration, which are critical aspects for OLP progression, but its implication in OLP pathogenesis has not been determined. In this study, we sought to explicate the effect of Sema4D on human oral keratinocytes and its capacity to drive CD8 + T-cell lesional trafficking via chemokine modulation. We found that upregulations of sSema4D in OLP tissues and blood were positively correlated with disease severity and activity. In vitro observation revealed that Sema4D induced C-X-C motif chemokine ligand 9/C-X-C motif chemokine ligand 10 production by binding to plexin-B1 via protein kinase B-NF-κB cascade in human oral keratinocytes, which elicited OLP CD8 + T-cell migration. We also confirmed using clinical samples that elevated C-X-C motif chemokine ligand 9/C-X-C motif chemokine ligand 10 levels were positively correlated with sSema4D levels in OLP lesions and serum. Notably, we determined matrix metalloproteinase-9 as a new proteolytic enzyme for the cleavage of sSema4D from the T-cell surface, which may contribute to the high levels of sSema4D in OLP lesions and serum. Our findings conclusively revealed an amplification feedback loop involving T cells, chemokines, and Sema4D-dependent signal that promotes OLP progression. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Kc167, a widely used Drosophila cell line, contains an active primary piRNA pathway.

PubMed

Vrettos, Nicholas; Maragkakis, Manolis; Alexiou, Panagiotis; Mourelatos, Zissimos

2017-01-01

PIWI family proteins bind to small RNAs known as PIWI-interacting RNAs (piRNAs) and play essential roles in the germline by silencing transposons and by promoting germ cell specification and function. Here we report that the widely used Kc167 cell line, derived from Drosophila melanogaster embryos, expresses piRNAs that are loaded to Aub and Piwi. Kc167 piRNAs are produced by a canonical, primary piRNA biogenesis pathway, from phased processing of precursor transcripts by the Zuc endonuclease, Armi helicase, and dGasz mitochondrial scaffold protein. Kc167 piRNAs derive from cytoplasmic transcripts, notably tRNAs and mRNAs, and their abundance correlates with that of parent transcripts. The expression of Aub is robust in Kc167, that of Piwi is modest, while Ago3 is undetectable, explaining the lack of transposon-related piRNA amplification by the Aub-Ago3, ping-pong mechanism. We propose that the default state of the primary piRNA biogenesis machinery is random transcript sampling to allow generation of piRNAs from any transcript, including newly acquired retrotransposons. This state is unmasked in Kc167, likely because they do not express piRNA cluster transcripts in sufficient amounts and do not amplify transposon piRNAs. We use Kc167 to characterize an inactive isoform of Aub protein. Since most Kc167 piRNAs are genic, they can be mapped uniquely to the genome, facilitating computational analyses. Furthermore, because Kc167 is a widely used and well-characterized cell line that is easily amenable to experimental manipulations, we expect that it will serve as an excellent system to study piRNA biogenesis and piRNA-related factors. © 2016 Vrettos et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

KC-135 on ramp

NASA Technical Reports Server (NTRS)

1958-01-01

The Boeing KC-135 Stratotanker, besides being used extensively in its primary role as an inflight aircraft refueler, has assisted in several projects at the NASA Dryden Flight Research Center, Edwards, California. In 1957 and 1958, Dryden was asked by what was then the Civil Aeronautics Administration (later absorbed into the Federal Aviation Administration (FAA) in 1958) to help establish new approach procedure guidelines on cloud-ceiling and visibility minimums for Boeing's first jet airliner, the B-707. Dryden used a KC-135 (the military variant of the 707), seen here on the runway at Edwards Air Force Base, to aid the CAA in these tests. In 1979 and 1980, Dryden was again involved with general aviation research with the KC-135. This time, a special wingtip 'winglet', developed by Richard Whitcomb of Langley Research Center, was tested on the jet aircraft. Winglets are small, nearly vertical fins installed on an airplane's wing tips to help produce a forward thrust in the vortices that typically swirl off the end of the wing, thereby reducing drag. This winglet idea was tested at the Dryden Flight Research Center on a KC-135A tanker loaned to NASA by the Air Force. The research showed that the winglets could increase an aircraft's range by as much as 7 percent at cruise speeds. The first application of NASA's winglet technology in industry was in general aviation business jets, but winglets are now being incorporated into most new commercial and military transport jets, including the Gulfstream III and IV business jets, the Boeing 747-400 and MD-11 airliners, and the C-17 military transport. In the 1980's, a KC-135 was used in support of the Space Shuttle program. Since the Shuttle was to be launched from Florida, researchers wanted to test the effect of rain on the sensitive thermal tiles. Tiles were mounted on special fixtures on an F-104 aircraft and a P-3 Orion. The F-104 was flown in actual rain conditions, and also behind the KC-135 spray tanker as it

KC-135 and Other Microgravity Simulations

NASA Technical Reports Server (NTRS)

2005-01-01

This document represents a summary of medical and scientific evaluations conducted aboard the KC-135 from June 23, 2004 to June 27, 2005. Included is a general overview of KC-135 activities manifested and coordinated by the Human Adaptation and Countermeasures Office. A collection of brief reports that describe tests conducted aboard the KC-135 follows the overview. Principal investigators and test engineers contributed significantly to the content of the report describing their particular experiment or hardware evaluation. This document concludes with an appendix that provides background information concerning the KC-135 and the Reduced-Gravity Program.

Identification of the platelet-derived chemokine CXCL4/PF-4 as a broad-spectrum HIV-1 inhibitor

PubMed Central

Auerbach, David J.; Lin, Yin; Miao, Huiyi; Cimbro, Raffaello; DiFiore, Michelle J.; Gianolini, Monica E.; Furci, Lucinda; Biswas, Priscilla; Fauci, Anthony S.; Lusso, Paolo

2012-01-01

The natural history of HIV-1 infection is highly variable in different individuals, spanning from a rapidly progressive course to a long-term asymptomatic infection. A major determinant of the pace of disease progression is the in vivo level of HIV-1 replication, which is regulated by a complex network of cytokines and chemokines expressed by immune and inflammatory cells. The chemokine system is critically involved in the control of HIV-1 replication by virtue of the role played by specific chemokine receptors, most notably CCR5 and CXCR4, as cell-surface coreceptors for HIV-1 entry; hence, the chemokines that naturally bind such coreceptors act as endogenous inhibitors of HIV-1. Here, we show that the CXC chemokine CXCL4 (PF-4), the most abundant protein contained within the α-granules of platelets, is a broad-spectrum inhibitor of HIV-1 infection. Unlike other known HIV-suppressive chemokines, CXCL4 inhibits infection by the majority of primary HIV-1 isolates regardless of their coreceptor-usage phenotype or genetic subtype. Consistent with the lack of viral phenotype specificity, blockade of HIV-1 infection occurs at the level of virus attachment and entry via a unique mechanism that involves direct interaction of CXCL4 with the major viral envelope glycoprotein, gp120. The binding site for CXCL4 was mapped to a region of the gp120 outer domain proximal to the CD4-binding site. The identification of a platelet-derived chemokine as an endogenous antiviral factor may have relevance for the pathogenesis and treatment of HIV-1 infection. PMID:22645343

Identification of the platelet-derived chemokine CXCL4/PF-4 as a broad-spectrum HIV-1 inhibitor.

PubMed

Auerbach, David J; Lin, Yin; Miao, Huiyi; Cimbro, Raffaello; Difiore, Michelle J; Gianolini, Monica E; Furci, Lucinda; Biswas, Priscilla; Fauci, Anthony S; Lusso, Paolo

2012-06-12

The natural history of HIV-1 infection is highly variable in different individuals, spanning from a rapidly progressive course to a long-term asymptomatic infection. A major determinant of the pace of disease progression is the in vivo level of HIV-1 replication, which is regulated by a complex network of cytokines and chemokines expressed by immune and inflammatory cells. The chemokine system is critically involved in the control of HIV-1 replication by virtue of the role played by specific chemokine receptors, most notably CCR5 and CXCR4, as cell-surface coreceptors for HIV-1 entry; hence, the chemokines that naturally bind such coreceptors act as endogenous inhibitors of HIV-1. Here, we show that the CXC chemokine CXCL4 (PF-4), the most abundant protein contained within the α-granules of platelets, is a broad-spectrum inhibitor of HIV-1 infection. Unlike other known HIV-suppressive chemokines, CXCL4 inhibits infection by the majority of primary HIV-1 isolates regardless of their coreceptor-usage phenotype or genetic subtype. Consistent with the lack of viral phenotype specificity, blockade of HIV-1 infection occurs at the level of virus attachment and entry via a unique mechanism that involves direct interaction of CXCL4 with the major viral envelope glycoprotein, gp120. The binding site for CXCL4 was mapped to a region of the gp120 outer domain proximal to the CD4-binding site. The identification of a platelet-derived chemokine as an endogenous antiviral factor may have relevance for the pathogenesis and treatment of HIV-1 infection.

Elevation of macrophage-derived chemokine in eosinophilic pneumonia: a role of alveolar macrophages.

PubMed

Manabe, Kazuyoshi; Nishioka, Yasuhiko; Kishi, Jun; Inayama, Mami; Aono, Yoshinori; Nakamura, Yoichi; Ogushi, Fumitaka; Bando, Hiroyasu; Tani, Kenji; Sone, Saburo

2005-02-01

Macrophage-derived chemokine (MDC/CCL22) and thymus-and activation-regulated chemokine (TARC/CCL17) are ligands for CC chemokine receptor 4. Recently, TARC has been reported to play a role in the pathogenesis of idiopathic eosinophilic pneumonia (IEP). The purpose of this study was to evaluate the role of MDC in IEP and other interstitial lung diseases (ILDs). MDC and TARC in the bronchoalveolar lavage fluid (BALF) were measured by enzyme-linked immunosorbent assay in patients with ILDs and healthy volunteers (HV). We also examined the expression of MDC mRNA in alveolar macrophages (AM) by real-time quantitative reverse transcriptase-polymerase chain reaction. Both MDC and TARC were detected only in BALF obtained from IEP patients. The concentration of MDC was higher than that of TARC in all cases. The level of MDC in IEP correlated with that of TARC. AM from IEP patients expressed a significantly higher amount of MDC than that from HV at the levels of protein and mRNA. MDC in BALF from IEP dramatically decreased when patients achieved remission. These findings suggest that MDC, in addition to TARC, might be involved in the pathogenesis of IEP, and AM play a role in the elevation of MDC in IEP.

The presence of betapapillomavirus antibodies around transplantation predicts the development of keratinocyte carcinoma in organ transplant recipients: a cohort study.

PubMed

Genders, Roel E; Mazlom, Hadi; Michel, Angelika; Plasmeijer, Elsemieke I; Quint, Koen D; Pawlita, Michael; van der Meijden, Els; Waterboer, Tim; de Fijter, Hans; Claas, Frans H; Wolterbeek, Ron; Feltkamp, Mariet C W; Bouwes Bavinck, Jan Nico

2015-05-01

Organ transplant recipients (OTRs) have an increased risk of developing keratinocyte carcinomas (KCs). The aim of this study was to correlate infection with human papillomaviruses (HPVs) belonging to the beta genus (Beta-papillomavirus (Beta-PV)) at transplantation with later development of KCs. In a cohort study, sera collected between 1 year before and 1 year after transplantation of OTRs transplanted between 1990 and 2006 were tested for antibody responses against the L1 capsid antigen of Beta-PV and other HPV genera (Gamma-, Mu-, Nu-, and Alpha-PV) using multiplex serology. The OTRs were followed for a maximum of 22 years. Cox regression models with KC, squamous cell carcinoma (SCC), and basal cell carcinoma (BCC) as outcome variables were used. Out of 445 OTRs, 60 had developed KC: 14 developed only SCC, 24 only BCC, and 22 both types of KC. The time-dependent hazard ratio (HR) to develop either or both types of KC, adjusted for age, sex, and transplanted organ, in tested Beta-PV-seropositive OTR around the time of transplantation compared with Beta-PV-seronegative OTR was 2.9 (95% confidence interval (CI) 1.3-6.4). The HR for SCC was 2.9 (95% CI 0.99-8.5) and for BCC it was 3.1 (95% CI 1.2-8.0). There was also an association between Mu-PV seropositivity and KC, but there were no significant associations between other HPV genera tested and KC. A positive seroresponse for Beta-PV around transplantation significantly predicted the development of KC in OTRs up to 22 years later, providing additional evidence that infection with Beta-PV has a role in KC carcinogenesis.

KC-135 and Other Microgravity Simulations

NASA Technical Reports Server (NTRS)

Skinner, Noel C.

1999-01-01

This document represents a summary of medical and scientific evaluations conducted aboard the KC-135 from June 20, 1998 to June 20, 1999. Included is a general overview of KC-135 activities manifested and coordinated by the Life Sciences Research Laboratories. A collection of brief reports that describes tests conducted aboard the KC-135 follows the overview. Principal investigators and test engineers contributed significantly to the content of the report describing their particular experiment or hardware evaluation. Although this document follows general guidelines, each report format may vary to accommodate differences in experiment design and procedures. This document concludes with an appendix that provides background information concerning the KC-135 and the Reduced-Gravity Program.

KC-135 and Other Microgravity Simulations

NASA Technical Reports Server (NTRS)

Skinner, Noel C.; Schlegel, Todd T. (Technical Monitor)

2001-01-01

This document represents a summary of medical and scientific evaluations conducted aboard the KC-135 from January to June 15, 2001. Included is a general overview of KC-135 activities manifested and coordinated by the Human Adaptation and Countermeasures Office. A collection of brief reports that describes tests conducted aboard the KC-135 follows the overview. Principal investigators and test engineers contributed significantly to the content of the report describing their particular experiment or hardware evaluation. Although this document follows general guidelines, each report format may vary to accommodate differences in experiment design and procedures. This document concludes with an appendix that provides background information concerning the KC-135 and the Reduced-Gravity Program.

Saussurea lappa alleviates inflammatory chemokine production in HaCaT cells and house dust mite-induced atopic-like dermatitis in Nc/Nga mice.

PubMed

Lim, Hye-Sun; Ha, Hyekyung; Lee, Mee-Young; Jin, Seong-Eun; Jeong, Soo-Jin; Jeon, Woo-Young; Shin, Na-Ra; Sok, Dai-Eun; Shin, Hyeun-Kyoo

2014-01-01

Saussurea lappa is a traditional herbal medicine used for to treat various inflammatory diseases. In this study, we investigated the protective effects of S. lappa against atopic dermatitis using human keratinocyte HaCaT cells, murine mast cell line MC/9 cells, and a house dust mite-induced atopic dermatitis model of Nc/Nga mice. Treatment with the S. lappa caused a significant reduction in the mRNA levels and production of inflammatory chemokines and cytokine, including thymus- and activation-regulated chemokine (TARC), macrophage-derived chemokine (MDC), regulated on activation, normal T-cell expressed and secreted (RANTES), and interleukin-8 (IL-8) in tumor necrosis factor-α/interferone-γ-stimulated HaCaT cells. S. lappa exhibited the significant reduction in histamine production in MC/9 cells. In the atopic dermatitis model, S. lappa significantly reduced the dermatitis score and serum IgE and TARC levels. In addition, the back skin and ears of S. lappa-treated Nc/Nga mice exhibited reduced histological manifestations of atopic skin lesions such as erosion, hyperplasia of the epidermis and dermis, and inflammatory cell infiltration. In conclusion, an extract of S. lappa effectively suppressed the development of atopic dermatitis, which was closely related to the reduction of chemokines and cytokine. Our study suggests that S. lappa may be a potential treatment for atopic dermatitis. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

CXC chemokine ligand 4 (CXCL4) down-regulates CC chemokine receptor expression on human monocytes.

PubMed

Schwartzkopff, Franziska; Petersen, Frank; Grimm, Tobias Alexander; Brandt, Ernst

2012-02-01

During acute inflammation, monocytes are essential in abolishing invading micro-organisms and encouraging wound healing. Recruitment by CC chemokines is an important step in targeting monocytes to the inflamed tissue. However, cell surface expression of the corresponding chemokine receptors is subject to regulation by various endogenous stimuli which so far have not been comprehensively identified. We report that the platelet-derived CXC chemokine ligand 4 (CXCL4), a known activator of human monocytes, induces down-regulation of CC chemokine receptors (CCR) 1, -2, and -5, resulting in drastic impairment of monocyte chemotactic migration towards cognate CC chemokine ligands (CCL) for these receptors. Interestingly, CXCL4-mediated down-regulation of CCR1, CCR2 and CCR5 was strongly dependent on the chemokine's ability to stimulate autocrine/paracrine release of TNF-α. In turn, TNF-α induced the secretion CCL3 and CCL4, two chemokines selective for CCR1 and CCR5, while the secretion of CCR2-ligand CCL2 was TNF-α-independent. Culture supernatants of CXCL4-stimulated monocytes as well as chemokine-enriched preparations thereof reproduced CXCL4-induced CCR down-regulation. In conclusion, CXCL4 may act as a selective regulator of monocyte migration by stimulating the release of autocrine, receptor-desensitizing chemokine ligands. Our results stress a co-ordinating role for CXCL4 in the cross-talk between platelets and monocytes during early inflammation.

Chemokines and chemokine receptors in chronic lymphocytic leukemia (CLL): from understanding the basics towards therapeutic targeting.

PubMed

Burger, Jan A

2010-12-01

Chemokines and their receptors organize the recruitment and positioning of cells at each stage of the immune response, a system critically dependent upon coordination to get the right cells to the right place at the right time. Chemokine receptors expressed on CLL B cells are thought to function in a similar fashion, regulating the trafficking of the leukemia cells between blood, lymphoid organs, and the bone marrow, and within sub compartments within these tissues, in concert with adhesion molecules and other guidance cues. CLL cells not only respond to chemokines secreted in the microenvironment, the leukemia cells also secrete chemokines in response to external signals, such as B cell receptor engagement. These CLL cell-derived chemokines facilitate interactions between CLL cells, T cells, and other immune cells that shape the CLL microenvironment. CXCR4, the most prominent chemokine receptor in CLL, is now targeted in a first clinical trial, emphasizing that chemokines and their receptors have become a highly dynamic translational research field. Copyright © 2010 Elsevier Ltd. All rights reserved.

Serum macrophage-derived chemokine (MDC) levels are closely related with the disease activity of atopic dermatitis

PubMed Central

KAKINUMA, T; NAKAMURA, K; WAKUGAWA, M; MITSUI, H; TADA, Y; SAEKI, H; TORII, H; KOMINE, M; ASAHINA, A; TAMAKI, K

2002-01-01

Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease characterized by the predominant infiltration of T cells, eosinophils and macrophages in lesional skin. Recently, macrophage-derived chemokine (MDC)/CCL22, a CC chemokine, was identified as a selective chemoattractant for CC chemokine receptor 4 (CCR4)-expressing cells, in addition to thymus and activation-regulated chemokine (TARC). We have previously reported that serum TARC levels correlate with the severity of AD. In this report, we investigated the participation of MDC in AD. First, we measured serum MDC levels in 45 patients with AD, 25 patients with psoriasis vulgaris and 25 healthy controls. Serum MDC levels in AD patients were significantly higher than those in healthy controls and psoriasis patients. Furthermore, the increases in serum MDC levels in AD patients were greater in the severely affected group than in the moderate or mild groups. We compared serum MDC levels in 11 AD patients, before and after treatment, and observed a significant decrease after treatment. Moreover, the serum MDC levels significantly correlated with the Scoring AD (SCORAD) index, serum soluble (s) E-selectin levels, serum soluble interleukin-2 receptor (sIL-2R) levels, serum TARC levels and eosinophil numbers in peripheral blood. Our study strongly suggests that serum MDC levels have a notable correlation with disease activity and that MDC, as well as the CC chemokine TARC, may be involved in the pathogenesis of AD. PMID:11876749

Interleukin 22 early affects keratinocyte differentiation, but not proliferation, in a three-dimensional model of normal human skin

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

Donetti, Elena, E-mail: elena.donetti@unimi.it; Cornaghi, Laura; Arnaboldi, Francesca

Interleukin (IL)-22 is a pro-inflammatory cytokine driving the progression of the psoriatic lesion with other cytokines, as Tumor Necrosis Factor (TNF)-alpha and IL-17. Our study was aimed at evaluating the early effect of IL-22 alone or in combination with TNF-alpha and IL-17 by immunofluorescence on i) keratinocyte (KC) proliferation, ii) terminal differentiation biomarkers as keratin (K) 10 and 17 expression, iii) intercellular junctions. Transmission electron microscopy (TEM) analysis was performed. A model of human skin culture reproducing a psoriatic microenvironment was used. Plastic surgery explants were obtained from healthy young women (n=7) after informed consent. Fragments were divided before addingmore » IL-22 or a combination of the three cytokines, and harvested 24 (T24), 48 (T48), and 72 (T72) h later. From T24, in IL-22 samples we detected a progressive decrease in K10 immunostaining in the spinous layer paralleled by K17 induction. By TEM, after IL-22 incubation, keratin aggregates were evident in the perinuclear area. Occludin immunostaining was not homogeneously distributed. Conversely, KC proliferation was not inhibited by IL-22 alone, but only by the combination of cytokines. Our results suggest that IL-22 affects keratinocyte terminal differentiation, whereas, in order to induce a proliferation impairment, a more complex psoriatic-like microenvironment is needed.« less

Intravesical Toll-like receptor 7 agonist R-837: Optimization of its formulation in an orthotopic mouse model of bladder cancer

PubMed Central

Hayashi, Tomoko; Crain, Brian; Corr, Maripat; Chan, Michael; Cottam, Howard B; Maj, Roberto; Barberis, Alcide; Leoni, Lorenzo; Carson, Dennis A

2013-01-01

Objective To study the immune response caused by the intravesical administration of the immunomodulator R-837 in various formulations and to estimate its therapeutic potential for bladder cancer. Methods Female C57BL/6 mice were intravesically treated with different formulations of R-837, a Toll-like receptor 7 agonist used for treating genital warts and skin malignancy. The tested formulation mixtures contained different ratios of lactic acid, a thermosensitive poloxamer polymer (Lutrol F127) and 2-(hydroxypropyl)-β-cyclodextrin (HPβCD). Induction of tumor necrosis factor α (TNFα) and keratinocyte-derived chemokine (KC) was analyzed by Luminex microbeads assay. The therapeutic potential of intravesical administration of R-837 was assessed in an orthotopic, syngeneic mouse model of bladder cancer using MB49 cells. Results Intravesical administration of R-837 in lactic acid alone induced systemic and bladder TNFα and KC in a dose-dependent manner. Formulations including poloxamer decreased systemic absorption of R-837 and significantly reduced systemic and local induction of KC. Addition of HPβCD in the poloxamer formulation particularly reversed levels of systemic and local levels of TNFα and KC. Histological examination showed that poloxamer-HPβCD formulation allowed infiltration of mononuclear cells into urothelium and lamina propria. In studies using orthotopic mouse bladder cancer, the tumor loads in R-837-treated mice were significantly lower than those in vehicle-treated or non-treated mice. Conclusion The optimized poloxamer-HPβCD formulation of R-837 shows therapeutic potential for bladder cancer while avoiding adverse side-effects. PMID:20337728

Citrullinated Chemokines in Rheumatoid Arthritis

DTIC Science & Technology

2015-10-01

1 AWARD NUMBER: W81XWH-13-1-0210 TITLE: Citrullinated Chemokines in Rheumatoid Arthritis PRINCIPAL INVESTIGATOR: David A. Fox CONTRACTING...CONTRACT NUMBER Citrullinated Chemokines in Rheumatoid Arthritis 5b. GRANT NUMBER W81XWH-13-1-0210 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) David A. Fox...citrulline, which contributes to the pathogenesis of rheumatoid arthritis (RA). We show that citrullinated epithelial- derived neutrophil-activating peptide 78

3,4,5-Tricaffeoylquinic acid inhibits tumor necrosis factor-α-stimulated production of inflammatory mediators in keratinocytes via suppression of Akt- and NF-κB-pathways.

PubMed

Lee, Chung Soo; Lee, Seon Ae; Kim, Yun Jeong; Seo, Seong Jun; Lee, Min Won

2011-11-01

Keratinocytes may play an important role in the pathogenesis of skin disease in atopic dermatitis. Caffeoyl derivatives are demonstrated to have anti-inflammatory and anti-oxidant effects. However, the effect of 3,4,5-tricaffeoylquinic acid prepared from Aconium koreanum on the pro-inflammatory cytokine-stimulated keratinocyte responses remains uncertain. In human keratinocytes, we investigated the effect of 3,4,5-tricaffeoylquinic acid on the tumor necrosis factor (TNF)-α-stimulated production of inflammatory mediators in relation to the nuclear factor (NF)-κB and cell signaling Akt, which regulates the transcription genes involved in immune and inflammatory responses. 3,4,5-Tricaffeoylquinic acid inhibited the TNF-α-stimulated production of cytokines (IL-1β and IL-8) and chemokine (CCL17 and CCL27) in keratinocytes. Bay 11-7085 (an inhibitor of NF-κB activation) and Akt inhibitor attenuated the TNF-α-induced formation of inflammatory mediators. 3,4,5-Tricaffeoylquinic acid, Bay 11-7085, Akt inhibitor and N-acetylcysteine inhibited the TNF-α-induced activation of NF-κB, activation of Akt, and formation of reactive oxygen and nitrogen species. The results show that 3,4,5-tricaffeoylquinic acid seems to attenuate the TNF-α-stimulated inflammatory mediator production in keratinocytes by suppressing the activation of Akt and NF-κB pathways which may be mediated by reactive oxygen species. The findings suggest that 3,4,5-tricaffeoylquinic acid may exert an inhibitory effect against the pro-inflammatory mediator-induced skin disease. Copyright © 2011 Elsevier B.V. All rights reserved.

Hypoxia enhances the wound-healing potential of adipose-derived stem cells in a novel human primary keratinocyte-based scratch assay.

PubMed

Riis, Simone; Newman, Rhonda; Ipek, Hilal; Andersen, Jens I; Kuninger, David; Boucher, Shayne; Vemuri, Mohan C; Pennisi, Cristian P; Zachar, Vladimir; Fink, Trine

2017-03-01

Preclinical studies have suggested that paracrine factors from adipose-derived stem cells (ASCs) promote the healing of chronic wounds, and that the exposure of ASCs to hypoxia enhances their wound healing effect. To aid the translation of these findings into clinical use, robust wound models are necessary to explore each aspect of wound healing. The aspect of re-epithelization is often studied in a scratch assay based on transformed keratinocytes. However, there are concerns regarding the validity of this model, since these cell lines differ from normal keratinocytes, both in terms of proliferative capacity and differentiation, and sensitivity to environmental cues. In this study, the main challenge of using primary keratinocytes to examine the effects of ASCs was identified to be their different requirements for calcium in the culture media. We confirmed that a high calcium content led to morphological and cytoskeletal changes in primary keratinocytes, and demonstrated that a low calcium content compromised the growth of ASCs. We found that it is possible to perform the wound healing assay with primary keratinocytes, if the conditioned media from the ASCs is dialyzed to reduce the calcium concentration. Additionally, using this model of re-epithelization, conditioned media from normoxic ASCs was shown to markedly increase the rate of wound closure by primary keratinocytes, and this effect was significantly enhanced with media from the hypoxia-exposed ASCs. These findings, which are in line with the observations from previous in vivo studies, highlight the validity of this modified assay to investigate the wound healing properties of ASCs in vitro.

The prevention of TNF-α/IFN-γ mixture-induced inflammation in human keratinocyte and atopic dermatitis-like skin lesions in Nc/Nga mice by mineral-balanced deep sea water.

PubMed

Lee, Kyu-Shik; Chun, So-Young; Lee, Min-Gu; Kim, Soyoung; Jang, Tae-Jung; Nam, Kyung-Soo

2018-01-01

Atopic dermatitis (AD) is a chronic inflammatory skin disease caused by environmental and chemical allergens. Despite the complexity of its pathogenesis, many investigations have shown that substances having anti-inflammatory activities alleviated the pathology of AD. Here, we evaluated the effects of mineral-balanced deep sea water (DSW) on AD-like skin damage in both in vitro and in vivo. The results showed that mineral-balanced DSW regressed inflammatory chemokines, such as macrophage-derived chemokine (MDC), thymus- and activation-regulated chemokine (TARC) and regulated on activation, normal T-cell expressed and secreted (RANTES), and cytokines, interleukin (IL)-6 and granulocyte-macrophage colony-stimulating factor (GM-CSF) mRNA expression in HaCaT immortal human keratinocyte treated with tumor necrosis factor (TNF)-α/ interferon (IFN)-γ mixture. Furthermore, increased cyclooxygenase (COX)-2 protein expressions were also reversed, filaggrin gene expression was enhanced and decreased involucrin transcriptions was recovered by mineral-balanced DSW in TNF-α/IFN-γ mixture-treated HaCaT human keratinocyte. Moreover, we revealed that the inhibitory effects of mineral-balanced DSW were mediated with the suppression of signal transducer and activator of transcription (STAT) 1 phosphorylation. In animal experiments, we showed that hardness 2000 of mineral-balanced DSW decreased the serum levels of IgE, IL-4, and histamine, and alleviated the severity score and numbers of scratching in dinitrochlorobezene (DNCB)-treated Nc/Nga mice. Furthermore, increased epidermal thickness and mast cell infiltration by DNCB treatment were reversed by the application of hardness 2000 mineral-balanced DSW. Taken together, the present investigation indicates that mineral-balanced DSW is a potent substance with anti-atopic dermatitis activity. Copyright © 2017. Published by Elsevier Masson SAS.

Mitigation effect of an FGF-2 peptide on acute gastrointestinal syndrome after high-dose ionizing radiation.

PubMed

Zhang, Lurong; Sun, Weimin; Wang, Jianjun; Zhang, Mei; Yang, Shanmin; Tian, Yeping; Vidyasagar, Sadasivan; Peña, Louis A; Zhang, Kunzhong; Cao, Yongbing; Yin, Liangjie; Wang, Wei; Zhang, Lei; Schaefer, Katherine L; Saubermann, Lawrence J; Swarts, Steven G; Fenton, Bruce M; Keng, Peter C; Okunieff, Paul

2010-05-01

Acute gastrointestinal syndrome (AGS) resulting from ionizing radiation causes death within 7 days. Currently, no satisfactory agent exists for mitigation of AGS. A peptide derived from the receptor binding domain of fibroblast growth factor 2 (FGF-P) was synthesized and its mitigation effect on AGS was examined. A subtotal body irradiation (sub-TBI) model was created to induce gastrointestinal (GI) death while avoiding bone marrow death. After 10.5 to 16 Gy sub-TBI, mice received an intramuscular injection of FGF-P (10 mg/kg/day) or saline (0.2 ml/day) for 5 days; survival (frequency and duration) was measured. Crypt cells and their proliferation were assessed by hematoxylin, eosin, and BrdU staining. In addition, GI hemoccult score, stool formation, and plasma levels of endotoxin, insulin, amylase, interleukin (IL)-6, keratinocyte-derived chemokine (KC) monocyte chemoattractant protein 1 (MCP-1) and tumor necrosis factor (TNF)-alpha were evaluated. Treatment with FGF-P rescued a significant fraction of four strains of mice (33-50%) exposed to a lethal dose of sub-TBI. Use of FGF-P improved crypt survival and repopulation and partially preserved or restored GI function. Furthermore, whereas sub-TBI increased plasma endotoxin levels and several pro-inflammation cytokines (IL-6, KC, MCP-1, and TNF-alpha), FGF-P reduced these adverse responses. The study data support pursuing FGF-P as a mitigator for AGS.

The Effect of Lipoaspirates on Human Keratinocytes.

PubMed

Kim, Bong-Sung; Gaul, Charel; Paul, Nora E; Dewor, Manfred; Stromps, Jan-Philipp; Hwang, Soo Seok; Nourbakhsh, Mahtab; Bernhagen, Jürgen; Rennekampff, Hans-Oliver; Pallua, Norbert

2016-09-01

One increasingly important trend in plastic, reconstructive, and aesthetic surgery is the use of fat grafts to improve cutaneous wound healing. In clinical practice, lipoaspirates (adipose tissue harvested by liposuction) are re-injected in a procedure called lipofilling. Previous studies, however, mainly evaluated the regenerative effect of isolated adipocytes, adipose-derived stem cells, and excised en bloc adipose tissue on keratinocytes, whereas no study to date has examined the effect of lipoaspirates. The authors aimed to investigate differences in the regenerative property of en bloc adipose tissue and lipoaspirates on keratinocytes. Human keratinocytes, lipoaspirates, and en bloc adipose tissue from 36 healthy donors were isolated. In vitro proliferation, differentiation, migration, stratification, and wound healing of keratinocyte monolayers were measured. Furthermore, secreted levels of VEGF, bFGF, IGF-1, MMP-9, and MIF were detected by ELISA. Migration, proliferation, and wound healing of keratinocytes were increased by lipoaspirates. Interestingly, the effect of lipoaspirates on keratinocyte proliferation was significantly higher than by en bloc adipose tissue after 5 days. The differentiation of keratinocytes was equally attenuated by lipoaspirates and en bloc adipose tissue. Stratification of keratinocyte layers was enhanced by lipoaspirates and en bloc fat when compared to controls. Lipoaspirates secrete higher levels of bFGF, whereas higher levels of VEGF and IGF-1 are released by en bloc adipose tissue. We show that lipoaspirates and en bloc adipose tissue have a regenerative effect on keratinocytes. One reason for the higher effect of lipoaspirates on keratinocyte proliferation may be the secretion of different cytokines. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

KC-46 Workforce Requirements for Depot Maintenance Activation

DTIC Science & Technology

2014-03-27

commercial derivative aircraft . These are aircraft originally designed for commercial aviation but with modifications that change the aircraft to fit the... designing the process to capture the data needed to infer answers to the research questions. More needs to be understood about how aircraft maintenance...Air Force projects receiving new KC-46 aircraft in 2016 and headquarters is directing organic maintenance. Oklahoma City ALC is the depot projected

Exosomes released by keratinocytes modulate melanocyte pigmentation

PubMed Central

Cicero, Alessandra Lo; Delevoye, Cédric; Gilles-Marsens, Floriane; Loew, Damarys; Dingli, Florent; Guéré, Christelle; André, Nathalie; Vié, Katell; van Niel, Guillaume; Raposo, Graça

2015-01-01

Cells secrete extracellular vesicles (EVs), exosomes and microvesicles, which transfer proteins, lipids and RNAs to regulate recipient cell functions. Skin pigmentation relies on a tight dialogue between keratinocytes and melanocytes in the epidermis. Here we report that exosomes secreted by keratinocytes enhance melanin synthesis by increasing both the expression and activity of melanosomal proteins. Furthermore, we show that the function of keratinocyte-derived exosomes is phototype-dependent and is modulated by ultraviolet B. In sum, this study uncovers an important physiological function for exosomes in human pigmentation and opens new avenues in our understanding of how pigmentation is regulated by intercellular communication in both healthy and diseased states. PMID:26103923

Furin is a chemokine-modifying enzyme: in vitro and in vivo processing of CXCL10 generates a C-terminally truncated chemokine retaining full activity.

PubMed

Hensbergen, Paul J; Verzijl, Dennis; Balog, Crina I A; Dijkman, Remco; van der Schors, Roel C; van der Raaij-Helmer, Elizabeth M H; van der Plas, Mariena J A; Leurs, Rob; Deelder, André M; Smit, Martine J; Tensen, Cornelis P

2004-04-02

Chemokines comprise a class of structurally related proteins that are involved in many aspects of leukocyte migration under basal and inflammatory conditions. In addition to the large number of genes, limited processing of these proteins by a variety of enzymes enhances the complexity of the total spectrum of chemokine variants. We have recently shown that the native chemokine CXCL10 is processed at the C terminus, thereby shedding the last four amino acids. The present study was performed to elucidate the mechanism in vivo and in vitro and to study the biological activity of this novel isoform of CXCL10. Using a combination of protein purification and mass spectrometric techniques, we show that the production of C-terminally truncated CXCL10 by primary keratinocytes is inhibited in vivo by a specific inhibitor of pro-protein convertases (e.g. furin) but not by inhibition of matrix metalloproteinases. Moreover, CXCL10 is processed by furin in vitro, which is abrogated by a mutation in the furin recognition site. Using GTPgammaS binding, Ca(2+) mobilization, and chemotaxis assays, we demonstrate that the C-terminally truncated CXCL10 variant is a potent ligand for CXCR3. Moreover, the inverse agonist activity on the virally encoded receptor ORF74 and the direct antibacterial activity of CXCL10 are fully retained. Hence, we have identified furin as a novel chemokine-modifying enzyme in vitro and most probably also in vivo, generating a C-terminally truncated CXCL10, which fully retains its (inverse) agonistic properties.

Intracrine sex steroid synthesis and signaling in human epidermal keratinocytes and dermal fibroblasts.

PubMed

Pomari, Elena; Dalla Valle, Luisa; Pertile, Paolo; Colombo, Lorenzo; Thornton, M Julie

2015-02-01

Peripheral intracrine sex steroid synthesis from adrenal precursors dehydroepiandrosterone (DHEA) and DHEA-sulfate has evolved in humans. We sought to establish if there are differences in intracrine, paracrine, and endocrine regulation of sex steroids by primary cultures of human skin epidermal keratinocytes and dermal fibroblasts. Microarray analysis identified multifunctional genes modulated by steroids, quantitative RT-PCR (qRT-PCR) mRNA expression, enzymatic assay aromatase activity, scratch assay cell migration, immunocytochemistry α-smooth muscle actin (α-SMA), and collagen gel fibroblast contraction. All steroidogenic components were present, although only keratinocytes expressed the organic anion organic anion transporter protein (OATP) 2B1 transporter. Both expressed the G-protein-coupled estrogen receptor (GPER1). Steroids modulated multifunctional genes, up-regulating genes important in repair and aging [angiopoietin-like 4 (ANGPTL4), chemokine (C-X-C motif) ligand 1 (CXCL1), lamin B1 (LMNB1), and thioredoxin interacting protein (TXNIP)]. DHEA-sulfate (DHEA-S), DHEA, and 17β-estradiol stimulated keratinocyte and fibroblast migration at early (4 h) and late (24-48 h) time points, suggesting involvement of genomic and nongenomic signaling. Migration was blocked by aromatase and steroid sulfatase (STS) inhibitors confirming intracrine synthesis to estrogen. Testosterone had little effect, implying it is not an intermediate. Steroids stimulated fibroblast contraction but not α-SMA expression. Mechanical wounding reduced fibroblast aromatase activity but increased keratinocyte activity, amplifying the bioavailability of intracellular estrogen. Cultured fibroblasts and keratinocytes provide a biologically relevant model system to investigate the complex pathways of sex steroid intracrinology in human skin. © FASEB.

Processing of natural and recombinant CXCR3-targeting chemokines and implications for biological activity.

PubMed

Hensbergen, P J; van der Raaij-Helmer, E M; Dijkman, R; van der Schors, R C; Werner-Felmayer, G; Boorsma, D M; Scheper, R J; Willemze, R; Tensen, C P

2001-09-01

Chemokines comprise a class of peptides with chemotactic activity towards leukocytes. The potency of different chemokines for the same receptor often varies as a result of differences in primary structure. In addition, post-translational modifications have been shown to affect the effectiveness of chemokines. Although in several studies, natural CXCR3-targeting chemokines have been isolated, detailed information about the proteins and their possible modifications is lacking. Using a combination of liquid chromatography and mass spectrometry we studied the protein profile of CXCR3-targeting chemokines expressed by interferon-gamma-stimulated human keratinocytes. The biological implications of one of the identified modifications was studied in more detail using calcium mobilization and chemotaxis assays. We found that the primary structure of human CXCL10 is different from the generally accepted sequence. In addition we identified a C-terminally truncated CXCL10, lacking the last four amino acids. Native CXCL11 was primarily found in its intact mature form but we also found a mass corresponding to an N-terminally truncated human CXCL11, lacking the first two amino acids FP, indicating that this chemokine is a substrate for dipeptidylpeptidase IV. Interestingly, this same truncation was found when we expressed human CXCL11 in Drosophila S2 cells. The biological activity of this truncated form of CXCL11 was greatly reduced, both in calcium mobilization (using CXCR3 expressing CHO cells) as well as its chemotactic activity for CXCR3-expressing T-cells. It is concluded that detailed information on chemokines at the protein level is important to characterize the exact profile of these chemotactic peptides as modifications can severely alter their biological activity.

Process modeling KC-135 aircraft

NASA Technical Reports Server (NTRS)

Workman, Gary L.

1991-01-01

Instrumentation will be provided for KC-135 aircraft which will provide a quantitative measure of g-level variation during parabolic flights and its effect on experiments which demonstrate differences in results obtained with differences in convective flow. The flight apparatus will provide video recording of the effects of the g-level variations on varying fluid samples. The apparatus will be constructed to be available to fly on the KC-135 during most missions.

Effects of Human Mesenchymal Stem Cells Coculture on Calcium-Induced Differentiation of Normal Human Keratinocytes.

PubMed

Sah, Shyam Kishor; Kim, Hae Young; Lee, Ji Hae; Lee, Seong-Wook; Kim, Hyung-Sik; Kim, Yeon-Soo; Kang, Kyung-Sun; Kim, Tae-Yoon

2017-06-01

The influence of mesenchymal stem cells (MSCs) on keratinocytes in altered microenvironments is poorly understood. Here, we cocultured umbilical cord blood-derived MSCs with normal human epidermal keratinocytes to evaluate their paracrine effect in the presence of high extracellular calcium (Ca 2+ ) concentration. High Ca 2+ environment to keratinocytes can disrupt normal skin barrier function due to abnormal/premature differentiation of keratinocytes. Surprisingly, we found that MSCs suppress both proliferation and differentiation of keratinocytes under a high Ca 2+ environment in transforming growth factors β1 (TGFβ1)-dependent manner. Furthermore, we determined that MSCs can regulate the mitogen-activated protein kinases, phosphatidylinositol 3-kinase/protein kinase B, and protein kinase C pathways in Ca 2+ -induced differentiated keratinocytes. Knockdown of TGFβ1 from MSCs results in decreased suppression of differentiation with significantly increased proliferation of keratinocytes compared with control MSCs. MSCs-derived TGFβ1 further induced growth inhibition of keratinocyte in high extracellular Ca 2+ environment as analyzed by a decrease in DNA synthesis, accumulation of phosphorylated retinoblastoma protein, cdc2, and increased mRNA level of p21, and independent of TGFβ1/SMAD pathway. Taken together, we found that MSCs-derived TGFβ1 is a critical regulator of keratinocyte function, and involves multiple proximal signaling cascades. Stem Cells 2017;35:1592-1602. © 2017 AlphaMed Press.

KC-135A in flight - winglet study

NASA Technical Reports Server (NTRS)

1979-01-01

The KC-135 with the winglets in flight over the San Gabriel mountains, south of Edwards AFB. While wind tunnel tests suggested that winglets - developed by NASA Langley's Richard Whitcomb - would significantly reduce drag, flight research proved their usefulness. Winglets were installed on an Air Force KC-135 and research flights were made in 1979 and 1980. These showed drag in flight was reduced by as much as 7 percent. Winglets soon appeared on production aircraft, although these were smaller than those mounted on the KC-135.

Stimulatory effect of fibroblast-derived prostaglandin E₂ on keratinocyte stratification in the skin equivalent.

PubMed

Arai, Koji Y; Fujioka, Atsuko; Okamura, Ryoko; Nishiyama, Toshio

2014-01-01

Epidermal-dermal interaction plays important roles in physiological events such as wound healing. In this study, we examined a double paracrine mechanism between keratinocytes and fibroblasts through interleukin-1 (IL-1) and an IL-1-induced inflammatory mediator prostaglandin E₂ (PGE₂) using the skin equivalent. The epidermal layer of the skin equivalent expressed high levels of IL-1α mRNA (IL1A mRNA) and relatively low levels of IL-1β mRNA (IL1B mRNA). IL1A mRNA was not detected in fibroblasts. Fibroblasts also expressed low but not negligible levels of IL1B mRNA only in the presence of keratinocytes. Expression of prostaglandin-endoperoxide synthase 2 mRNA (PTGS2 mRNA) and production of PGE₂ in three-dimensionally cultured fibroblasts were noticeably stimulated by co-culture with keratinocytes, whereas PTGS2 mRNA expression in the epidermal layer was very low. In addition, hydroxyprostaglandin dehydrogenase 15-(NAD) mRNA was highly expressed in keratinocytes but not in fibroblasts, and exogenous IL-1β stimulated PTGS2 mRNA expression in the dermal equivalent. The thickness of the epidermal layer and the number of MKI67-positive keratinocytes in the skin equivalent were decreased by treatment with indomethacin, and the decrease recovered when exogenous PGE₂ was added. These results indicate that keratinocytes stimulate their own proliferation through a double paracrine mechanism mediated by IL-1 and PGE₂. © 2014 by the Wound Healing Society.

Interferon Regulatory Factor 6 Has a Protective Role in the Host Response to Endotoxic Shock

PubMed Central

Volk, Paige; Moreland, Jessica G.; Dunnwald, Martine

2016-01-01

Interferon Regulatory Factor (IRF) 6, a member of the IRF family, is essential for epidermal and orofacial embryonic development. Irf6 is strongly expressed in keratinocytes, in which it regulates epidermal proliferation, differentiation, and migration. A recent role for Irf6 in Toll-like receptor 2-dependent chemokine gene expression was also reported in an epithelial cell line. However, a function for Irf6 in innate immune cells was not previously reported. In the present study, we investigated the expression and function of Irf6 in bone marrow-derived neutrophils and macrophages. We show here, using a conditional knockout of Irf6 in lysosymeM expressing cells, that Irf6 is required for resistance to LPS-induced endotoxic shock. In addition, Irf6-deficient bone marrow-derived neutrophils exhibited increased chemotactic index and velocity compared with wild-type cells in vitro. TLR4-specific KC and IL6 secretions were upregulated in Irf6-deficient bone marrow-derived macrophages in vitro. These cells also exhibited an increased level of phosphorylated IkBa. Collectively, our findings suggest a role for Irf6 in the resistance to endotoxic shock due to NFk-B-mediated alteration of cytokine production. PMID:27035130

Mitigation Effect of an FGF-2 Peptide on Acute Gastrointestinal Syndrome After High-Dose Ionizing Radiation

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

Zhang Lurong; Sun Weimin; Wang Jianjun

Purpose: Acute gastrointestinal syndrome (AGS) resulting from ionizing radiation causes death within 7 days. Currently, no satisfactory agent exists for mitigation of AGS. A peptide derived from the receptor binding domain of fibroblast growth factor 2 (FGF-P) was synthesized and its mitigation effect on AGS was examined. Methods and Materials: A subtotal body irradiation (sub-TBI) model was created to induce gastrointestinal (GI) death while avoiding bone marrow death. After 10.5 to 16 Gy sub-TBI, mice received an intramuscular injection of FGF-P (10 mg/kg/day) or saline (0.2 ml/day) for 5 days; survival (frequency and duration) was measured. Crypt cells and theirmore » proliferation were assessed by hematoxylin, eosin, and BrdU staining. In addition, GI hemoccult score, stool formation, and plasma levels of endotoxin, insulin, amylase, interleukin (IL)-6, keratinocyte-derived chemokine (KC) monocyte chemoattractant protein 1 (MCP-1) and tumor necrosis factor (TNF)-alpha were evaluated. Results: Treatment with FGF-P rescued a significant fraction of four strains of mice (33-50%) exposed to a lethal dose of sub-TBI. Use of FGF-P improved crypt survival and repopulation and partially preserved or restored GI function. Furthermore, whereas sub-TBI increased plasma endotoxin levels and several pro-inflammation cytokines (IL-6, KC, MCP-1, and TNF-alpha), FGF-P reduced these adverse responses. Conclusions: The study data support pursuing FGF-P as a mitigator for AGS.« less

Chemokines and chemokine receptors: new insights into cancer-related inflammation

PubMed Central

Lazennec, Gwendal; Richmond, Ann

2010-01-01

Chemokines are involved in cellular interactions and tropism in situations frequently associated with inflammation. Recently, the importance of chemokines and chemokine receptors in inflammation associated with carcinogenesis has been highlighted. Increasing evidence suggests that chemokines are produced by tumor cells and also by cells of the tumor microenvironment including cancer-associated fibroblasts, mesenchymal stem cells, endothelial cells, tumor-associated macrophages and more recently tumor-associated neutrophils. In addition to having effects on tumor cell proliferation, angiogenesis and metastasis, chemokines also appear to modulate senescence and cell survival. Here, we review recent progress on the roles of chemokines and chemokine receptors in cancer-related inflammation, and we discuss the mechanisms underlying chemokine action in cancer that might facilitate the development of novel therapies in the future. PMID:20163989

Chemokines and chemokine receptors: new insights into cancer-related inflammation.

PubMed

Lazennec, Gwendal; Richmond, Ann

2010-03-01

Chemokines are involved in cellular interactions and tropism in situations frequently associated with inflammation. Recently, the importance of chemokines and chemokine receptors in inflammation associated with carcinogenesis has been highlighted. Increasing evidence suggests that chemokines are produced by tumor cells as well as by cells of the tumor microenvironment including cancer-associated fibroblasts (CAFs), mesenchymal stem cells (MSCs), endothelial cells, tumor-associated macrophages (TAMs) and more recently tumor-associated neutrophils (TANs). In addition to affecting tumor cell proliferation, angiogenesis and metastasis, chemokines also seem to modulate senescence and cell survival. Here, we review recent progress on the roles of chemokines and chemokine receptors in cancer-related inflammation, and discuss the mechanisms underlying chemokine action in cancer that might facilitate the development of novel therapies in the future. Copyright 2010 Elsevier Ltd. All rights reserved.

Evidence of functional cross talk between the Notch and NF-κB pathways in nonneoplastic hyperproliferating colonic epithelium.

PubMed

Ahmed, Ishfaq; Roy, Badal; Chandrakesan, Parthasarathy; Venugopal, Anand; Xia, Lijun; Jensen, Roy; Anant, Shrikant; Umar, Shahid

2013-02-15

The Notch and NF-κB signaling pathways regulate stem cell function and inflammation in the gut, respectively. We investigate whether a functional cross talk exists between the two pathways during transmissible murine colonic hyperplasia (TMCH) caused by Citrobacter rodentium (CR). During TMCH, NF-κB activity and subunit phosphorylation in colonic crypts of NIH Swiss mice at days 6 and 12 were associated with increases in downstream target CXC chemokine ligand (CXCL)-1/keratinocyte-derived chemokine (KC) expression. Blocking Notch signaling acutely for 5 days with the Notch blocker dibenzazepine (DBZ) failed to inhibit crypt NF-κB activity or CXCL-1/KC expression. Chronic DBZ administration for 10 days, however, blocked Notch and NF-κB signaling in the crypts and abrogated hyperplasia. Intriguingly, chronic Notch inhibition was associated with significant increases in IL-1α, granulocyte colony-stimulating factor, monocyte chemoattractant protein 1, macrophage inflammatory protein 2, and KC in the crypt-denuded lamina propria or whole distal colon, with concomitant increases in myeloperoxidase activity. In core-3(-/-) mice, which are defective in intestinal mucin, DBZ administration replicated the results of NIH Swiss mice; in Apc(Min/+) mice, which are associated with CR-induced elevation of NF-κB-p65(276) expression, DBZ reversed the increase in NF-κB-p65(276), which may have blocked rapid proliferation of the mutated crypts. DBZ further blocked reporter activities involving the NF-κB-luciferase reporter plasmid or the Toll-like receptor 4/NF-κB/SEAPorter HEK-293 reporter cell line, while ectopic expression of Notch-N(ICD) reversed the inhibitory effect. Dietary bael (Aegle marmelos) extract (4%) and curcumin (4%) restored Notch and NF-κB cross talk in NIH Swiss mice, inhibited CR/DBZ-induced apoptosis in the crypts, and promoted crypt regeneration. Thus functional cross talk between the Notch and NF-κB pathways during TMCH regulates hyperplasia and

KC-135A in flight - winglet study

NASA Technical Reports Server (NTRS)

1979-01-01

This Boeing KC-135 Stratotanker, besides being used extensively in its primary role as an inflight aircraft refueler, has assisted in several projects at the NASA Dryden Flight Research Center, Edwards, California. In 1979 and 1980, Dryden was involved with general aviation research with the KC-135. A special wingtip 'winglet', developed by Richard Whitcomb of Langley Research Center, was tested on the jet aircraft. Winglets are small, nearly vertical fins installed on an airplane's wing tips to help produce a forward thrust in the vortices that typically swirl off the end of the wing, thereby reducing drag. This winglet idea was tested at the Dryden Flight Research Center on a KC-135A tanker loaned to NASA by the Air Force. The research showed that the winglets could increase an aircraft's range by as much as 7 percent at cruise speeds. The first application of NASA's winglet technology in industry was in general aviation business jets, but winglets are now being incorporated into most new commercial and military transport jets, including the Gulfstream III and IV business jets, the Boeing 747-400 and MD-11 airliners, and the C-17 military transport. In 1957 and 1958, Dryden was asked by what was then the Civil Aeronautics Administration (later absorbed into the Federal Aviation Administration (FAA) in 1958) to help establish new approach procedure guidelines on cloud-ceiling and visibility minimums for Boeing's first jet airliner, the B-707. Dryden used a KC-135, the military variant of the 707, to aid the CAA in these tests. In the 1980's, a KC-135 was used in support of the Space Shuttle program. Since the Shuttle was to be launched from Florida, researchers wanted to test the effect of rain on the sensitive thermal tiles. Tiles were mounted on special fixtures on an F-104 aircraft and a P-3 Orion. The F-104 was flown in actual rain conditions, and also behind the KC-135 spray tanker as it released water. The KC-135, however, proved incapable of simulating

Functional Characterization of Cultured Keratinocytes after Acute Cutaneous Burn Injury

PubMed Central

Gauglitz, Gerd G.; Zedler, Siegfried; v. Spiegel, Felix; Fuhr, Jasmin; v. Donnersmarck, Guido Henkel; Faist, Eugen

2012-01-01

Background In addition to forming the epithelial barrier against the outside environment keratinocytes are immunologically active cells. In the treatment of severely burned skin, cryoconserved keratinocyte allografts gain in importance. It has been proposed that these allografts accelerate wound healing also due to the expression of a favourable - keratinocyte-derived - cytokine and growth factor milieu. Methods In this study the morphology and cytokine expression profile of keratinocytes from skin after acute burn injury was compared to non-burned skin. Skin samples were obtained from patients after severe burn injury and healthy controls. Cells were cultured and secretion of selected inflammatory mediators was quantified using Bioplex Immunoassays. Immunohistochemistry was performed to analyse further functional and morphologic parameters. Results Histology revealed increased terminal differentiation of keratinocytes (CK10, CK11) in allografts from non-burned skin compared to a higher portion of proliferative cells (CK5, vimentin) in acute burn injury. Increased levels of IL-1α, IL-2, IL-4, IL-10, IFN-γ and TNFα could be detected in culture media of burn injury skin cultures. Both culture groups contained large amounts of IL-1RA. IL-6 and GM-CSF were increased during the first 15 days of culture of burned skin compared to control skin. Levels of VEGF, FGF-basic, TGF-ß und G-CSF were high in both but not significantly different. Cryoconservation led to a diminished mediator synthesis except for higher levels of intracellular IL-1α and IL-1ß. Conclusion Skin allografts from non-burned skin show a different secretion pattern of keratinocyte-derived cytokines and inflammatory mediators compared to keratinocytes after burn injury. As these secreted molecules exert auto- and paracrine effects and subsequently contribute to healing and barrier restoration after acute burn injury therapies affecting this specific cytokine/growth factor micromilieu could be

Various members of the Toll-like receptor family contribute to the innate immune response of human epidermal keratinocytes

PubMed Central

Köllisch, Gabriele; Kalali, Behnam Naderi; Voelcker, Verena; Wallich, Reinhard; Behrendt, Heidrun; Ring, Johannes; Bauer, Stefan; Jakob, Thilo; Mempel, Martin; Ollert, Markus

2005-01-01

Toll-like receptors (TLRs) are important pattern recognition molecules that activate the nuclear factor (NF)-κB pathway leading to the production of antimicrobial immune mediators. As keratinocytes represent the first barrier against exogenous pathogens in human skin, we investigated their complete functional TLR1–10 expression profile. First, reverse transcription–polymerase chain reaction (PCR) analysis revealed a very similar pattern of TLR mRNA expression when comparing freshly isolated human epidermis and cultured primary human keratinocytes. Thus, further experiments were carried out with primary keratinocytes in comparison with the spontaneously immortalized human keratinocyte cell line HaCaT. The quantitative expression of TLR1–10 mRNA in real-time PCR of primary human keratinocytes and HaCaT cells was analysed. Both cell types constitutively expressed TLR2, TLR3, TLR5, and to a lesser extent TLR10. TLR4 was only found in HaCaT cells, TLR1 to a higher degree in primary keratinocytes. In line with this, LPS induced mRNA expression of CD14 and TLR4 only in HaCaT cells. After stimulation with various TLR ligands, the NF-κB-activated chemokine interleukin-8 (IL-8) was measured. In primary keratinocytes and HaCaT cells the TLR3 ligand poly (I:C) was the most potent stimulator of IL-8 secretion. The TLR ligands peptidoglycan, Pam3Cys and flagellin which bind to TLR2, TLR1/TLR2 heterodimer, and TLR5, respectively, also induced IL-8 secretion, whereas no IL-8 was induced by LPS, R-848, loxoribine and cytosine guanine dinucleotide-containing oligodeoxynucleotide. A corresponding pattern was found in the RelA NF-κB translocation assay after ligand stimulation of primary keratinocytes. These studies provide substantial evidence for a functional TLR expression and signalling profile of normal human keratinocytes contributing to the antimicrobial defence barrier of human skin. PMID:15804290

Cyclic stretch induces upregulation of endothelin-1 with keratinocytes in vitro: Possible role in mechanical stress-induced hyperpigmentation

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

Kurita, Masakazu, E-mail: masakazukurita@gmail.com; Okazaki, Mutsumi; Fujino, Takashi

2011-05-27

Highlights: {yields} Influence of cyclic stretch on melanogenetic paracrine cytokines was investigated. {yields} Keratinocyte-derived endothelin-1 was upregulated with cyclic stretch. {yields} Degree of upregulation increases dose-dependently. {yields} This upregulation possibly plays a role in the pathogenesis of pigmented disorders. -- Abstract: The aim of this study was to investigate the possible pathological relation between mechanical stress and hyperpigmentation. We did this by investigating the influence of cyclic stretch on the expression of keratinocyte- and fibroblast-derived melanogenetic paracrine cytokines in vitro. Using primary human keratinocytes and fibroblasts, alterations of mRNA expression of melanogenetic paracrine cytokines due to cyclic stretch were investigatedmore » using a real-time polymerase chain reaction (PCR). The cytokines included basic fibroblast growth factor (bFGF), stem cell factor (SCF), granulocyte/macrophage colony-stimulating factor, interleukin-1{alpha}, and endothelin-1 (ET-1) for keratinocytes and bFGF, SCF, and hepatocyte growth factor for fibroblasts. The dose dependence of keratinocyte-derived ET-1 upregulation was further investigated using real-time PCR and an enzyme-linked immunosorbent assay. We also investigated the effects of cyclic stretch on the proliferation and differentiation of keratinocytes. Among the melanogenetic paracrine cytokines investigated, keratinocyte-derived ET-1 was consistently upregulated in all four cell lines. The degree of upregulation increased with the degree of the length and frequency of the stretch; in contrast, cell number and differentiation markers showed no obvious alterations with cyclic stretch. Keratinocyte-derived ET-1 upregulation possibly plays a significant role in the pathogenesis of pigmented disorders, such as friction melanosis, caused by mechanical stress.« less

Cyclooxygenases in human and mouse skin and cultured human keratinocytes: association of COX-2 expression with human keratinocyte differentiation

NASA Technical Reports Server (NTRS)

Leong, J.; Hughes-Fulford, M.; Rakhlin, N.; Habib, A.; Maclouf, J.; Goldyne, M. E.

1996-01-01

Epidermal expression of the two isoforms of the prostaglandin H-generating cyclooxygenase (COX-1 and COX-2) was evaluated both by immunohistochemistry performed on human and mouse skin biopsy sections and by Western blotting of protein extracts from cultured human neonatal foreskin keratinocytes. In normal human skin, COX-1 immunostaining is observed throughout the epidermis whereas COX-2 immunostaining increases in the more differentiated, suprabasilar keratinocytes. Basal cell carcinomas express little if any COX-1 or COX-2 immunostaining whereas both isozymes are strongly expressed in squamous cell carcinomas deriving from a more differentiated layer of the epidermis. In human keratinocyte cultures, raising the extracellular calcium concentration, a recognized stimulus for keratinocyte differentiation, leads to an increased expression of both COX-2 protein and mRNA; expression of COX-1 protein, however, shows no significant alteration in response to calcium. Because of a recent report that failed to show COX-2 in normal mouse epidermis, we also looked for COX-1 and COX-2 immunostaining in sections of normal and acetone-treated mouse skin. In agreement with a previous report, some COX-1, but no COX-2, immunostaining is seen in normal murine epidermis. However, following acetone treatment, there is a marked increase in COX-1 expression as well as the appearance of significant COX-2 immunostaining in the basal layer. These data suggest that in human epidermis as well as in human keratinocyte cultures, the expression of COX-2 occurs as a part of normal keratinocyte differentiation whereas in murine epidermis, its constitutive expression is absent, but inducible as previously published.

TRPV2 channel inhibitors attenuate fibroblast differentiation and contraction mediated by keratinocyte-derived TGF-β1 in an in vitro wound healing model of rats.

PubMed

Ishii, Taro; Uchida, Kunitoshi; Hata, Shozaburo; Hatta, Mitsutoki; Kita, Tomo; Miyake, Yuki; Okamura, Kazuhiko; Tamaoki, Sachio; Ishikawa, Hiroyuki; Yamazaki, Jun

2018-06-01

Keratinocytes release several factors that are involved in wound contracture and scar formation. We previously reported that a three-dimensional reconstruction model derived from rat skin represents a good wound healing model. We characterized the role of transient receptor potential (TRP) channels in the release of transforming growth factor (TGF)-β1 from keratinocytes and the differentiation of fibroblasts to identify possible promising pharmacological approaches to prevent scar formation and contractures. The three-dimensional culture model was made from rat keratinocytes seeded on a collagen gel in which dermal fibroblasts had been embedded. Among the TRP channel inhibitors tested, the TRPV2 inhibitors SKF96365 and tranilast attenuated most potently keratinocyte-dependent and - independent collagen gel contraction due to TGF-β signaling as well as TGF-β1 release from keratinocytes and α-smooth muscle actin production in myofibroblasts. Besides the low amounts detected in normal dermis, TRPV2 mRNA and protein levels were increased after fibroblasts were embedded in the gel. TRPV2 was also expressed in the epidermis and keratinocyte layers of the model. Both inhibitors and TRPV2 siRNA attenuated the intracellular increase of Ca 2+ induced by the TRPV agonist 2-aminoethoxydiphenyl borate in TGF-β1-pretreated fibroblasts. This is the first study to show that compounds targeting TRPV2 channels ameliorate wound contraction through the inhibition of TGF-β1 release and the differentiation of dermal fibroblasts in a culture model. Copyright © 2018. Published by Elsevier B.V.

Collagen XVII (BP180) modulates keratinocyte expression of the proinflammatory chemokine, IL-8.

PubMed

Van den Bergh, Françoise; Eliason, Steven L; Burmeister, Brian T; Giudice, George J

2012-08-01

Collagen XVII (COL17), a transmembrane protein expressed in epidermal keratinocytes (EK), is targeted by pathogenic autoantibodies in bullous pemphigoid. Treatment of EK with anti-COL17 autoantibodies triggers the production of proinflammatory cytokines. In this study, we test the hypothesis that COL17 is involved in the regulation of the EK proinflammatory response, using IL-8 expression as the primary readout. The absence of COL17 in EK derived from a junctional epidermolysis bullosa patient or shRNA-mediated knockdown of COL17 in normal EK resulted in a dysregulation of IL-8 responses under various conditions. The COL17-deficient cells showed an abnormally high IL-8 response after treatment with lipopolysaccharide (LPS), ultraviolet-B radiation or tumor necrosis factor, but exhibited a blunted IL-8 response to phorbol 12-myristate 13-acetate exposure. Induction of COL17 expression in COL17-negative EK led to a normalization of the LPS-induced proinflammatory response. Although α6β4 integrin was found to be up-regulated in COL17-deficient EK, siRNA-mediated knockdown of the α6 and β4 subunits revealed that COL17's effects on the LPS IL-8 response are not dependent on this integrin. In LPS-treated cells, inhibition of NF-kappa B activity in COL17-negative EK resulted in a normalization of their IL-8 response, and expression of an NF-kappa B-driven reporter was shown to be higher in COL17-deficient, compared with normal EK. These findings support the hypothesis that COL17 plays an important regulatory role in the EK proinflammatory response, acting largely via NF-kappa B. Future investigations will focus on further defining the molecular basis of this novel control network. © 2012 John Wiley & Sons A/S.

Collagen XVII (BP180) Modulates Keratinocyte Expression of the Proinflammatory Chemokine, IL-8

PubMed Central

Van den Bergh, Françoise; Eliason, Steven L.; Burmeister, Brian T.; Giudice, George J.

2012-01-01

Collagen XVII (COL17), a transmembrane protein expressed in epidermal keratinocytes (EK), is targeted by pathogenic autoantibodies in bullous pemphigoid. Treatment of EK with anti-COL17 autoantibodies triggers the production of proinflammatory cytokines. In this paper we test the hypothesis that COL17 is involved in the regulation of the EK proinflammatory response, using IL-8 expression as the primary readout. The absence of COL17 in EK derived from a junctional epidermolysis bullosa patient or shRNA-mediated knockdown of COL17 in normal EK resulted in a dysregulation of IL-8 responses under various conditions. The COL17-deficient cells showed an abnormally high IL-8 response after treatment with lipopolysaccharide (LPS), ultraviolet-B radiation or tumor necrosis factor, but exhibited a blunted IL-8 response to phorbol 12-myristate 13-acetate exposure. Induction of COL17 expression in COL17-negative EK led to a normalization of the LPS-induced proinflammatory response. Although α6β4 integrin was found to be up-regulated in COL17-deficient EK, siRNA-mediated knockdown of the α6 and β4 subunits revealed that COL17’s effects on the LPS IL-8 response are not dependent on this integrin. In LPS-treated cells, inhibition of NF-kappa B activity in COL17-negative EK resulted in a normalization of their IL-8 response, and expression of an NF-kappa B-driven reporter was shown to be higher in COL17-deficient, compared with normal, EK. These findings support the hypothesis that COL17 plays an important regulatory role in the EK proinflammatory response, acting largely via NF-kappa B. Future investigations will focus on further defining the molecular basis of this novel control network. PMID:22775995

Chemokine interactome mapping enables tailored intervention in acute and chronic inflammation.

PubMed

von Hundelshausen, Philipp; Agten, Stijn M; Eckardt, Veit; Blanchet, Xavier; Schmitt, Martin M; Ippel, Hans; Neideck, Carlos; Bidzhekov, Kiril; Leberzammer, Julian; Wichapong, Kanin; Faussner, Alexander; Drechsler, Maik; Grommes, Jochen; van Geffen, Johanna P; Li, He; Ortega-Gomez, Almudena; Megens, Remco T A; Naumann, Ronald; Dijkgraaf, Ingrid; Nicolaes, Gerry A F; Döring, Yvonne; Soehnlein, Oliver; Lutgens, Esther; Heemskerk, Johan W M; Koenen, Rory R; Mayo, Kevin H; Hackeng, Tilman M; Weber, Christian

2017-04-05

Chemokines orchestrate leukocyte trafficking and function in health and disease. Heterophilic interactions between chemokines in a given microenvironment may amplify, inhibit, or modulate their activity; however, a systematic evaluation of the chemokine interactome has not been performed. We used immunoligand blotting and surface plasmon resonance to obtain a comprehensive map of chemokine-chemokine interactions and to confirm their specificity. Structure-function analyses revealed that chemokine activity can be enhanced by CC-type heterodimers but inhibited by CXC-type heterodimers. Functional synergism was achieved through receptor heteromerization induced by CCL5-CCL17 or receptor retention at the cell surface via auxiliary proteoglycan binding of CCL5-CXCL4. In contrast, inhibitory activity relied on conformational changes (in CXCL12), affecting receptor signaling. Obligate CC-type heterodimers showed high efficacy and potency and drove acute lung injury and atherosclerosis, processes abrogated by specific CCL5-derived peptide inhibitors or knock-in of an interaction-deficient CXCL4 variant. Atheroprotective effects of CCL17 deficiency were phenocopied by a CCL5-derived peptide disrupting CCL5-CCL17 heterodimers, whereas a CCL5 α-helix peptide mimicked inhibitory effects on CXCL12-driven platelet aggregation. Thus, formation of specific chemokine heterodimers differentially dictates functional activity and can be exploited for therapeutic targeting. Copyright © 2017, American Association for the Advancement of Science.

Persea americana Mill. Seed: Fractionation, Characterization, and Effects on Human Keratinocytes and Fibroblasts

PubMed Central

Ramos-Jerz, Maria del R.; Villanueva, Socorro; Jerz, Gerold; Winterhalter, Peter; Deters, Alexandra M.

2013-01-01

Methanolic avocado (Persea americana Mill., Lauraceae) seed extracts were separated by preparative HSCCC. Partition and HSCCC fractions were principally characterized by LC-ESI-MS/MS analysis. Their in vitro influence was investigated on proliferation, differentiation, cell viability, and gene expression on HaCaT and normal human epidermal keratinocytes (NHEK) and normal human dermal fibroblasts (NHDF). The methanol-water partition (M) from avocado seeds and HSCCC fraction 3 (M.3) were mostly composed of chlorogenic acid and its isomers. Both reduced NHDF but enhanced HaCaT keratinocytes proliferation. HSCCC fraction M.2 composed of quinic acid among chlorogenic acid and its isomers inhibited proliferation and directly induced differentiation of keratinocytes as observed on gene and protein level. Furthermore, M.2 increased NHDF proliferation via upregulation of growth factor receptors. Salidrosides and ABA derivatives present in HSCCC fraction M.6 increased NHDF and keratinocyte proliferation that resulted in differentiation. The residual solvent fraction M.7 contained among low concentrations of ABA derivatives high amounts of proanthocyanidins B1 and B2 as well as an A-type trimer and stimulated proliferation of normal cells and inhibited the proliferation of immortalized HaCaT keratinocytes. PMID:24371457

The chemokine receptor CCR1 is identified in mast cell-derived exosomes

PubMed Central

Liang, Yuting; Qiao, Longwei; Peng, Xia; Cui, Zelin; Yin, Yue; Liao, Huanjin; Jiang, Min; Li, Li

2018-01-01

Mast cells are important effector cells of the immune system, and mast cell-derived exosomes carrying RNAs play a role in immune regulation. However, the molecular function of mast cell-derived exosomes is currently unknown, and here, we identify differentially expressed genes (DEGs) in mast cells and exosomes. We isolated mast cells derived exosomes through differential centrifugation and screened the DEGs from mast cell-derived exosomes, using the GSE25330 array dataset downloaded from the Gene Expression Omnibus database. Biochemical pathways were analyzed by Gene ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway on the online tool DAVID. DEGs-associated protein-protein interaction networks (PPIs) were constructed using the STRING database and Cytoscape software. The genes identified from these bioinformatics analyses were verified by qRT-PCR and Western blot in mast cells and exosomes. We identified 2121 DEGs (843 up and 1278 down-regulated genes) in HMC-1 cell-derived exosomes and HMC-1 cells. The up-regulated DEGs were classified into two significant modules. The chemokine receptor CCR1 was screened as a hub gene and enriched in cytokine-mediated signaling pathway in module one. Seven genes, including CCR1, CD9, KIT, TGFBR1, TLR9, TPSAB1 and TPSB2 were screened and validated through qRT-PCR analysis. We have achieved a comprehensive view of the pivotal genes and pathways in mast cells and exosomes and identified CCR1 as a hub gene in mast cell-derived exosomes. Our results provide novel clues with respect to the biological processes through which mast cell-derived exosomes modulate immune responses. PMID:29511430

The chemokine receptor CCR1 is identified in mast cell-derived exosomes.

PubMed

Liang, Yuting; Qiao, Longwei; Peng, Xia; Cui, Zelin; Yin, Yue; Liao, Huanjin; Jiang, Min; Li, Li

2018-01-01

Mast cells are important effector cells of the immune system, and mast cell-derived exosomes carrying RNAs play a role in immune regulation. However, the molecular function of mast cell-derived exosomes is currently unknown, and here, we identify differentially expressed genes (DEGs) in mast cells and exosomes. We isolated mast cells derived exosomes through differential centrifugation and screened the DEGs from mast cell-derived exosomes, using the GSE25330 array dataset downloaded from the Gene Expression Omnibus database. Biochemical pathways were analyzed by Gene ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway on the online tool DAVID. DEGs-associated protein-protein interaction networks (PPIs) were constructed using the STRING database and Cytoscape software. The genes identified from these bioinformatics analyses were verified by qRT-PCR and Western blot in mast cells and exosomes. We identified 2121 DEGs (843 up and 1278 down-regulated genes) in HMC-1 cell-derived exosomes and HMC-1 cells. The up-regulated DEGs were classified into two significant modules. The chemokine receptor CCR1 was screened as a hub gene and enriched in cytokine-mediated signaling pathway in module one. Seven genes, including CCR1, CD9, KIT, TGFBR1, TLR9, TPSAB1 and TPSB2 were screened and validated through qRT-PCR analysis. We have achieved a comprehensive view of the pivotal genes and pathways in mast cells and exosomes and identified CCR1 as a hub gene in mast cell-derived exosomes. Our results provide novel clues with respect to the biological processes through which mast cell-derived exosomes modulate immune responses.

The gene expression of cytokines and chemokines induced by tourniquet shock in mice.

PubMed

Tanaka, Jin; Ishida, Yuko; Ohshima, Tohru; Kondo, Toshikazu

2003-09-01

Traumatic shock is one of the major fields in forensic pathology, but its mechanism remains elusive from the pathophysiological aspects. Tourniquet shock has been established as one of the animal models of traumatic shock, and we examined the gene expression of cytokines and chemokines in the lung and liver in tourniquet shock using mice. Tourniquet was conducted by the application of elastic bands with five turns at both the thighs as high as possible for 2 h, followed by reperfusion. In this procedure, more than 90% mice died within 48 h after reperfusion. Serum hepatic transaminase and hematocrit values significantly increased at 2 h after reperfusion, and their elevation was still evident after 10 h. Histopathologically, hemorrhages, congestion and leukocyte recruitment were observed in the lung and liver specimens after 6 h of reperfusion. Immunohistochemical analysis with anti-myeloperoxidase antibody demonstrated a massive neutrophil infiltration in the lung and liver at 2 h or more after reperfusion. RT-PCR analyses demonstrated that the gene expression of interleukin-1beta, tumor necrosis factor-alpha, monocytes chemoattractant protein-1, macrophage inflammatory protein (MIP)-1alpha, MIP-2, KC and vascular endothelial adhesion molecule-1 was most enhanced in the lung and liver at 2 h after reperfusion. Thus, the gene expression of cytokines and chemokines is presumed to be closely related with the onset of tourniquet shock. From the forensic aspects, these cytokines and chemokines are considered to be useful markers for the early diagnosis of tourniquet shock.

Senator Jake Garn on the KC-135

NASA Technical Reports Server (NTRS)

1985-01-01

Senator Jake Garn appears to be springing from a trampoline in this scene, taken during a brief period of weightlessness provided by a parabola flown by the KC-135. Jeff Bingham, an aide to the senator, floats freely nearby (25616); Sen. Garn and Jeff Bingham prepare to ease from a partially anchored position to a totally free flying mode during a brief weightless session (25617); Sen. Garn gets an initial 'feel' of weightlessness as his feet float freely while he anchors himself with his hands. Seated nearby is his aide Bingham (25618); Sen. Garn (background) shares some of the ceiling space of the KC-135 with Bingham (25619); Sen. Garn (foreground) takes a seat behind the KC-135's crew in the forward cabin. Roger Zweig and Joseph S. Algranti, pilot and co-pilot, are partially visible in the background (25620).

Cysteine Cathepsins Activate ELR Chemokines and Inactivate Non-ELR Chemokines*

PubMed Central

Repnik, Urska; Starr, Amanda E.; Overall, Christopher M.; Turk, Boris

2015-01-01

Cysteine cathepsins are primarily lysosomal proteases involved in general protein turnover, but they also have specific proteolytic functions in antigen presentation and bone remodeling. Cathepsins are most stable at acidic pH, although growing evidence indicates that they have physiologically relevant activity also at neutral pH. Post-translational proteolytic processing of mature chemokines is a key, yet underappreciated, level of chemokine regulation. Although the role of selected serine proteases and matrix metalloproteases in chemokine processing has long been known, little has been reported about the role of cysteine cathepsins. Here we evaluated cleavage of CXC ELR (CXCL1, -2, -3, -5, and -8) and non-ELR (CXCL9–12) chemokines by cysteine cathepsins B, K, L, and S at neutral pH by high resolution Tris-Tricine SDS-PAGE and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Whereas cathepsin B cleaved chemokines especially in the C-terminal region, cathepsins K, L, and S cleaved chemokines at the N terminus with glycosaminoglycans modulating cathepsin processing of chemokines. The functional consequences of the cleavages were determined by Ca2+ mobilization and chemotaxis assays. We show that cysteine cathepsins inactivate and in some cases degrade non-ELR CXC chemokines CXCL9–12. In contrast, cathepsins specifically process ELR CXC chemokines CXCL1, -2, -3, -5, and -8 N-terminally to the ELR motif, thereby generating agonist forms. This study suggests that cysteine cathepsins regulate chemokine activity and thereby leukocyte recruitment during protective or pathological inflammation. PMID:25833952

Grasping objects autonomously in simulated KC-135 zero-g

NASA Technical Reports Server (NTRS)

Norsworthy, Robert S.

1994-01-01

The KC-135 aircraft was chosen for simulated zero gravity testing of the Extravehicular Activity Helper/retriever (EVAHR). A software simulation of the EVAHR hardware, KC-135 flight dynamics, collision detection and grasp inpact dynamics has been developed to integrate and test the EVAHR software prior to flight testing on the KC-135. The EVAHR software will perform target pose estimation, tracking, and motion estimation for rigid, freely rotating, polyhedral objects. Manipulator grasp planning and trajectory control software has also been developed to grasp targets while avoiding collisions.

Foreskin-isolated keratinocytes provide successful extemporaneous autologous paediatric skin grafts.

PubMed

Mcheik, Jiad N; Barrault, Christine; Pedretti, Nathalie; Garnier, Julien; Juchaux, Franck; Levard, Guillaume; Morel, Franck; Lecron, Jean-Claude; Bernard, François-Xavier

2016-03-01

Severe burns in children are conventionally treated with split-thickness skin autografts or epidermal sheets. However, neither early complete healing nor quality of epithelialization is satisfactory. An alternative approach is to graft isolated keratinocytes. We evaluated paediatric foreskin and auricular skin as donor sources, autologous keratinocyte transplantation, and compared the graft efficiency to the in vitro capacities of isolated keratinocytes to divide and reconstitute epidermal tissue. Keratinocytes were isolated from surgical samples by enzymatic digestion. Living cell recovery, in vitro proliferation and epidermal reconstruction capacities were evaluated. Differentiation status was analysed, using qRT-PCR and immunolabelling. Eleven children were grafted with foreskin-derived (boys) or auricular (girls) keratinocyte suspensions dripped onto deep severe burns. The aesthetic and functional quality of epithelialization was monitored in a standardized way. Foreskin keratinocyte graft in male children provides for the re-epithelialization of partial deep severe burns and accelerates wound healing, thus allowing successful wound closure, and improves the quality of scars. In accordance, in vitro studies have revealed a high yield of living keratinocyte recovery from foreskin and their potential in terms of regeneration and differentiation. We report a successful method for grafting paediatric males presenting large severe burns through direct spreading of autologous foreskin keratinocytes. This alternative method is easy to implement, improves the quality of skin and minimizes associated donor site morbidity. In vitro studies have highlighted the potential of foreskin tissue for graft applications and could help in tissue selection with the prospect of grafting burns for girls. Copyright © 2013 John Wiley & Sons, Ltd.

Efficient generation of integration-free human induced pluripotent stem cells from keratinocytes by simple transfection of episomal vectors.

PubMed

Piao, Yulan; Hung, Sandy Shen-Chi; Lim, Shiang Y; Wong, Raymond Ching-Bong; Ko, Minoru S H

2014-07-01

Keratinocytes represent an easily accessible cell source for derivation of human induced pluripotent stem (hiPS) cells, reportedly achieving higher reprogramming efficiency than fibroblasts. However, most studies utilized a retroviral or lentiviral method for reprogramming of keratinocytes, which introduces undesirable transgene integrations into the host genome. Moreover, current protocols of generating integration-free hiPS cells from keratinocytes are mostly inefficient. In this paper, we describe a more efficient, simple-to-use, and cost-effective method for generating integration-free hiPS cells from keratinocytes. Our improved method using lipid-mediated transfection achieved a reprogramming efficiency of ∼0.14% on average. Keratinocyte-derived hiPS cells showed no integration of episomal vectors, expressed stem cell-specific markers and possessed potentials to differentiate into all three germ layers by in vitro embryoid body formation as well as in vivo teratoma formation. To our knowledge, this represents the most efficient method to generate integration-free hiPS cells from keratinocytes. ©AlphaMed Press.

STS 61-B crewmembers training on the KC-135 in zero-G

NASA Image and Video Library

1985-08-21

STS 61-B crewmembers training on the KC-135 in zero-G. Views include Payload specialist Charles D. Walker attempting to down the lower torso of his extravehicular mobility unit (EMU) in zero-G in the KC-135. He is being assisted by other participants in the training (39135); Payload specialist Rodolfo Neri floating in midair during training in the KC-135 (39136,39138); Mission specialist Mary L. Cleave floating in midair during her training aboard the KC-135 (39137); Astronaut Bryan D. O'Connor assists Astronaut Sherwood C. Spring in completing his donning of the EMU in the KC-135 (39139); Technicians aid Spring with his EMU in the KC-135 (39140); O'Connor appears to be leaping up in zero-G aboard the KC-135 (39141); Astronaut Brewster Shaw is assisted by a technician to don his EMU (39142); Shaw is attempting to don the EMU gloves while O'Connor watches (39143); Shaw does jumping jacks while Neri attempts to travel down a rope guideline (39144).

α-Fetoprotein as a modulator of the pro-inflammatory response of human keratinocytes

PubMed Central

Potapovich, AI; Pastore, S; Kostyuk, VA; Lulli, D; Mariani, V; De Luca, C; Dudich, EI; Korkina, LG

2009-01-01

Background and purpose: The immunomodulatory effects of α-fetoprotein (AFP) on lymphocytes and macrophages have been described in vitro and in vivo. Recombinant forms of human AFP have been proposed as potential therapeutic entities for the treatment of autoimmune diseases. We examined the effects of embryonic and recombinant human AFP on the spontaneous, UVA- and cytokine-induced pro-inflammatory responses of human keratinocytes. Experimental approach: Cultures of primary and immortalized human keratinocytes (HaCaT) and human blood T lymphocytes were used. The effects of AFP on cytokine expression were studied by bioplexed elisa and quantitative reverse transcriptase polymerase chain reaction assay. Kinase and nuclear factor kappa B (NFκB) phosphorylation were quantified by intracellular elisa. Nuclear activator protein 1 and NFκB DNA binding activity was measured by specific assays. Nitric oxide and H2O2 production and redox status were assessed by fluorescent probe and biochemical methods. Key results: All forms of AFP enhanced baseline expression of cytokines, chemokines and growth factors. AFP dose-dependently increased tumour necrosis factor alpha-stimulated granulocyte macrophage colony stimulating factor and interleukin 8 expression and decreased tumour necrosis factor alpha-induced monocyte chemotactic protein 1 and IP-10 (interferon gamma-produced protein of 10 kDa) expression. AFP induced a marked activator protein 1 activation in human keratinocytes. AFP also increased H2O2 and modulated nitrite/nitrate levels in non-stimulated keratinocytes whereas it did not affect these parameters or cytokine release from UVA-stimulated cells. Phosphorylation of extracellular signal-regulated kinase (ERK1/2) and Akt1 but not NFκB was activated by AFP alone or by its combination with UVA. Conclusions and implications: Exogenous AFP induces activation of human keratinocytes, with de novo expression of a number of pro-inflammatory mediators and modulation of their

Optical signatures of bulk and solutions of KC{sub 8} and KC{sub 24}

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

Tristant, Damien; LPCNO, UMR-5215 CNRS, INSA, Université Fédérale de Toulouse-Midi-Pyrénées, Université de Toulouse, 135 Avenue de Rangueil, 31077 Toulouse; Wang, Yu

2015-07-28

We first performed an analysis of the shape of the Raman features of potassium-intercalated graphite at stage 1 (KC{sub 8} GIC) and 2 (KC{sub 24} GIC), respectively. By varying the excitation energy from ultraviolet to infrared, we observed a sign change of the Fano coupling factor below and above the optical transition related to the shift of the Fermi level which was determined from first principle calculations. This behavior is explained by a sign change in the Raman scattering amplitude of the electronic continuum. The GICs were then dissolved in two different solvents (N-Methyl-2-pyrrolidone and tetrahydrofuran), and the absorbance ofmore » the graphenide solutions obtained was measured in the UV range. Two peaks were observed which correspond to the maximum of the computed imaginary part of the optical index.« less

Chimeric Human Skin Substitute Tissue: A Novel Treatment Option for the Delivery of Autologous Keratinocytes.

PubMed

Rasmussen, Cathy A; Allen-Hoffmann, B Lynn

2012-04-01

For patients suffering from catastrophic burns, few treatment options are available. Chimeric coculture of patient-derived autologous cells with a "carrier" cell source of allogeneic keratinocytes has been proposed as a means to address the complex clinical problem of severe skin loss. Currently, autologous keratinocytes are harvested, cultured, and expanded to form graftable epidermal sheets. However, epidermal sheets are thin, are extremely fragile, and do not possess barrier function, which only develops as skin stratifies and matures. Grafting is typically delayed for up to 4 weeks to propagate a sufficient quantity of the patient's cells for application to wound sites. Fully stratified chimeric bioengineered skin substitutes could not only provide immediate wound coverage and restore barrier function, but would simultaneously deliver autologous keratinocytes to wounds. The ideal allogeneic cell source for this application would be an abundant supply of clinically evaluated, nontumorigenic, pathogen-free, human keratinocytes. To evaluate this potential cell-based therapy, mixed populations of a green fluorescent protein-labeled neonatal human keratinocyte cell line (NIKS) and unlabeled primary keratinocytes were used to model the allogeneic and autologous components of chimeric monolayer and organotypic cultures. Relatively few autologous keratinocytes may be required to produce fully stratified chimeric skin substitute tissue substantially composed of autologous keratinocyte-derived regions. The need for few autologous cells interspersed within an allogeneic "carrier" cell population may decrease cell expansion time, reducing the time to patient application. This study provides proof of concept for utilizing NIKS keratinocytes as the allogeneic carrier for the generation of bioengineered chimeric skin substitute tissues capable of providing immediate wound coverage while simultaneously supplying autologous human cells for tissue regeneration.

Evapotranspiration and crop coefficients for a super intensive olive orchard. An application of SIMDualKc and METRIC models using ground and satellite observations

NASA Astrophysics Data System (ADS)

Paço, Teresa A.; Pôças, Isabel; Cunha, Mário; Silvestre, José C.; Santos, Francisco L.; Paredes, Paula; Pereira, Luís S.

2014-11-01

The estimation of crop evapotranspiration (ETc) from the reference evapotranspiration (ETo) and a standard crop coefficient (Kc) in olive orchards requires that the latter be adjusted to planting density and height. The use of the dual Kc approach may be the best solution because the basal crop coefficient Kcb represents plant transpiration and the evaporation coefficient reproduces the soil coverage conditions and the frequency of wettings. To support related computations for a super intensive olive orchard, the model SIMDualKc was adopted because it uses the dual Kc approach. Alternatively, to consider the physical characteristics of the vegetation, the satellite-based surface energy balance model METRIC™ - Mapping EvapoTranspiration at high Resolution using Internalized Calibration - was used to estimate ETc and to derive crop coefficients. Both approaches were compared in this study. SIMDualKc model was calibrated and validated using sap-flow measurements of the transpiration for 2011 and 2012. In addition, eddy covariance estimation of ETc was also used. In the current study, METRIC™ was applied to Landsat images from 2011 to 2012. Adaptations for incomplete cover woody crops were required to parameterize METRIC. It was observed that ETc obtained from both approaches was similar and that crop coefficients derived from both models showed similar patterns throughout the year. Although the two models use distinct approaches, their results are comparable and they are complementary in spatial and temporal scales.

Directing Adipose-Derived Stem Cells into Keratinocyte-Like Cells: Impact of Medium Composition and Culture Condition.

PubMed

Petry, L; Kippenberger, S; Meissner, M; Kleemann, J; Kaufmann, R; Rieger, U M; Wellenbrock, S; Reichenbach, G; Zöller, N; Valesky, E

2018-04-28

Adipose-derived stem cells (ASC) are known to transdifferentiate into a wide range of different cell species in vitro including along the epidermal lineage. This property makes them a promising tool for regenerative medicine in order to restore the epidermal barrier. The present study is dedicated to identify in vitro conditions enabling transdifferentiation to a keratinocyte-like phenotype. Especially, the impact of different culture conditions (media compositions, 2D-, 3D-cultures) and extracellular matrix (ECM) molecules was evaluated. ASC derived from subcutaneous abdominal fat were characterized by stemness associated markers and subjected to different media. Epithelial differentiation in 2D cultures was monitored by pan-cytokeratin expression using flow cytometry and immunocytochemistry. In order to evaluate the impact of different ECM molecules on epidermal stratification, 3D cultures were produced, lifted to the air-liquid-interface (ALI) and examined by histological analysis and quantitative real-time RT-PCR. We identified a medium composition containing retinoic acid, hydrocortisone, ascorbic acid and BMP-4 enabling maximum pan-cytokeratin expression in 2D cultures. Moreover, adhesion to type IV collagen further promotes the pan-cytokeratin expression. When cultures were lifted to the ALI, significant stratification was observed, particularly in supports coated with type IV collagen or fibronectin. Moreover, epidermal differentiation markers (involucrin, cytokeratin 1 and 14) become induced. Conditions with hampered wound healing such as non-healing ulcers demand new treatment regimes. The here introduced optimized protocols for transdifferentiation of ASC into keratinocyte-like cells may help to establish more effective treatment procedures. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Receptor for advanced glycation endproducts (RAGE) maintains pulmonary structure and regulates the response to cigarette smoke.

PubMed

Wolf, Lisa; Herr, Christian; Niederstraßer, Julia; Beisswenger, Christoph; Bals, Robert

2017-01-01

The receptor for advanced glycation endproducts (RAGE) is highly expressed in the lung but its physiological functions in this organ is still not completely understood. To determine the contribution of RAGE to physiological functions of the lung, we analyzed pulmonary mechanics and structure of wildtype and RAGE deficient (RAGE-/-) mice. RAGE deficiency spontaneously resulted in a loss of lung structure shown by an increased mean chord length, increased respiratory system compliance, decreased respiratory system elastance and increased concentrations of serum protein albumin in bronchoalveolar lavage fluids. Pulmonary expression of RAGE was mainly localized on alveolar epithelial cells and alveolar macrophages. Primary murine alveolar epithelial cells isolated from RAGE-/- mice revealed an altered differentiation and defective barrier formation under in vitro conditions. Stimulation of interferone-y (IFNy)-activated alveolar macrophages deficient for RAGE with Toll-like receptor (TLR) ligands resulted in significantly decreased release of proinflammatory cytokines and chemokines. Exposure to chronic cigarette smoke did not affect emphysema-like changes in lung parenchyma in RAGE-/- mice. Acute cigarette smoke exposure revealed a modified inflammatory response in RAGE-/- mice that was characterized by an influx of macrophages and a decreased keratinocyte-derived chemokine (KC) release. Our data suggest that RAGE regulates the differentiation of alveolar epithelial cells and impacts on the development and maintenance of pulmonary structure. In cigarette smoke-induced lung pathology, RAGE mediates inflammation that contributes to lung damage.

The Antimicrobial Peptide Human Beta-Defensin-3 Is Induced by Platelet-Released Growth Factors in Primary Keratinocytes

PubMed Central

Lammel, Justus; Tohidnezhad, Mersedeh; Lippross, Sebastian; Behrendt, Peter; Klüter, Tim; Pufe, Thomas; Cremer, Jochen; Jahr, Holger; Rademacher, Franziska; Gläser, Regine; Harder, Jürgen

2017-01-01

Platelet-released growth factors (PRGF) and its related clinically used formulations (e.g., Vivostat Platelet-Rich Fibrin (PRF®)) contain a variety of chemokines, cytokines, and growth factors and are therefore used to support healing of chronic, hard-to-heal, or infected wounds. Human beta-defensin-3 (hBD-3) is an antimicrobial peptide inducibly expressed in human keratinocytes especially upon wounding. The potent antimicrobial activity of hBD-3 together with its wound closure-promoting activities suggests that hBD-3 may play a crucial role in wound healing. Therefore, we analyzed the influence of PRGF on hBD-3 expression in human primary keratinocytes in vitro. In addition, we investigated the influence of Vivostat PRF on hBD-3 expression in artificially generated human skin wounds in vivo. PRGF treatment of primary keratinocytes induced a significant, concentration- and time-dependent increase in hBD-3 gene expression which was partially mediated by the epidermal growth factor receptor (EGFR). In line with these cell culture data, in vivo experiments revealed an enhanced hBD-3 expression in experimentally produced human wounds after the treatment with Vivostat PRF. Thus, the induction of hBD-3 may contribute to the beneficial effects of thrombocyte concentrate lysates in the treatment of chronic or infected wounds. PMID:28811680

The histamine-synthesizing enzyme histidine decarboxylase is upregulated by keratinocytes in atopic skin.

PubMed

Gutowska-Owsiak, D; Greenwald, L; Watson, C; Selvakumar, T A; Wang, X; Ogg, G S

2014-10-01

Histamine is an abundant mediator accumulating in the skin of atopic patients, where it is thought to be derived from immune cells. While keratinocytes express histidine decarboxylase (HDC), levels of the enzyme in normal or diseased epidermis and factors that influence its expression in human keratinocytes are not known. To assess levels of HDC in inflammatory skin diseases and factors influencing its expression. Normal and filaggrin-insufficient human keratinocytes, organotypic epidermal models and skin samples were investigated for the expression of HDC. The effect of cytokines, bacterial and allergen stimuli exposure and functional changes in differentiation were evaluated in vitro. We detected abundant expression of the HDC protein in all models studied; expression was increased in atopic skin samples. Filaggrin-insufficient keratinocytes maintained HDC levels, but exposure of keratinocytes to thymic stromal lymphopoietin, tumour necrosis factor-α, lipopolysaccharide (LPS) and house dust mite (HDM) extract increased HDC expression in vitro. Furthermore, filaggrin expression in cultured keratinocytes increased following histamine depletion. Keratinocytes express abundant HDC protein, and the levels increase in atopic skin. LPS, HDM and cytokines, which are implicated in allergic inflammation, promote the expression of the enzyme and upregulate histamine levels in keratinocytes. Actively produced histamine influences keratinocyte differentiation, suggesting functional relevance of the axis to atopic dermatitis. The findings therefore identify a new point of therapeutic intervention. © 2014 British Association of Dermatologists.

Tretinoin and the prevention of keratinocyte carcinoma (Basal and squamous cell carcinoma of the skin): a veterans affairs randomized chemoprevention trial.

PubMed

Weinstock, Martin A; Bingham, Stephen F; Digiovanna, John J; Rizzo, Amilcar E; Marcolivio, Kim; Hall, Russell; Eilers, David; Naylor, Mark; Kirsner, Robert; Kalivas, James; Cole, Gary; Vertrees, Julia E

2012-06-01

Keratinocyte carcinoma (KC) is the most common cancer in the United States, with no proven means for prevention other than systemic retinoids, which have significant toxicity, and sunscreen. Topical tretinoin has been used for KC chemoprevention, although this use is unproven. Hence, we conducted the randomized Veterans Affairs Topical Tretinoin Chemoprevention Trial of high-dose topical tretinoin for KC prevention. We randomized 1,131 patients to topical 0.1% tretinoin or a matching vehicle control for 1.5-5.5 years. The primary outcomes were time to development of new basal cell carcinoma (BCC) and new invasive squamous cell carcinoma (SCC) on the face or ears. The effects were not significant (P=0.3 for BCC and P=0.4 for SCC). The proportions of the tretinoin and control groups who developed a BCC at 5 years were 53 and 54% and an invasive SCC at 5 years were 28 and 31%. These differences (95% confidence intervals) were: for BCC, 1.0% (-6.5, 8.6%); for SCC, 3.6% (-3.1, 10.3%). No differences were observed in any cancer-related end points or in actinic keratosis counts. The only quality of life difference was worse symptoms in the tretinoin group at 12 months after randomization. This trial in high-risk patients demonstrates that high-dose topical tretinoin is ineffective at reducing risk of KCs.

Chemokines and chemokine receptors: new actors in neuroendocrine regulations.

PubMed

Rostène, William; Guyon, Alice; Kular, Lara; Godefroy, David; Barbieri, Federica; Bajetto, Adriana; Banisadr, Ghazal; Callewaere, Céline; Conductier, Gregory; Rovère, Carole; Mélik-Parsadaniantz, Stéphane; Florio, Tullio

2011-01-01

Chemokines are small secreted proteins that chemoattract and activate immune and non-immune cells. Their role in the immune system is well-known, and it has recently been suggested that they may also play a role in the central nervous system (CNS). Indeed, they do not only act as immunoinflammatory mediators in the brain but they also act as potential modulators in neurotransmission. Although we are only beginning to be aware of the implication of chemokines in neuroendocrine functions, this review aims at summarizing what is known in that booming field of research. First we describe the expression of chemokines and their receptors in the CNS with a focus on the hypothalamo-pituitary system. Secondly, we present what is known on some chemokines in the regulation of neuroendocrine functions such as cell migration, stress, thermoregulation, drinking and feeding as well as anterior pituitary functions. We suggest that chemokines provide a fine modulatory tuning system of neuroendocrine regulations. Copyright © 2010 Elsevier Inc. All rights reserved.

Transferrin-derived synthetic peptide induces highly conserved pro-inflammatory responses of macrophages.

PubMed

Haddad, George; Belosevic, Miodrag

2009-02-01

We examined the induction of macrophage pro-inflammatory responses by transferrin-derived synthetic peptide originally identified following digestion of transferrin from different species (murine, bovine, human N-lobe and goldfish) using elastase. The mass spectrometry analysis of elastase-digested murine transferrin identified a 31 amino acid peptide located in the N2 sub-domain of the transferrin N-lobe, that we named TMAP. TMAP was synthetically produced and shown to induce a number of pro-inflammatory genes by quantitative PCR. TMAP induced chemotaxis, a potent nitric oxide response, and TNF-alpha secretion in different macrophage populations; P338D1 macrophage-like cells, mouse peritoneal macrophages, mouse bone marrow-derived macrophages (BMDM) and goldfish macrophages. The treatment of BMDM cultures with TMAP stimulated the production of nine cytokines and chemokines (IL-6, MCP-5, MIP-1 alpha, MIP-1 gamma, MIP-2, GCSF, KC, VEGF, and RANTES) that was measured using cytokine antibody array and confirmed by Western blot. Our results indicate that transferrin-derived peptide, TMAP, is an immunomodulating molecule capable of inducing pro-inflammatory responses in lower and higher vertebrates.

2010 MoDOT kcICON survey : final report, February 2010.

DOT National Transportation Integrated Search

2010-02-01

The survey measures the Kansas City area residents satisfaction with the kcICON project, their perceptions of MoDOT as a result : of the project and what, if anything, would impress them regarding the kcICON project. A professional calling center ...

KC-135A in flight - winglet study

NASA Technical Reports Server (NTRS)

1979-01-01

During the 1970s, the focus at Dryden shifted from high-speed and high-altitude flight to incremental improvements in technology and aircraft efficiency. One manifestation of this trend occurred in the winglet flight research carried out on a KC-135 during 1979 and 1980. Richard Whitcomb at the Langley Research Center had originated the idea of adding small vertical fins to an aircraft's wing tips. His wind tunnel tests indicated that winglets produced a forward thrust, which reduced the strength of the vortices generated by an aircraft's wing tips and resulted in a reduction of drag and an increase in aircraft range. Whitcomb, who had previously developed the area rule concept and the supercritical wing, selected the best winglet shape for flight tests on a KC-135 tanker. When the tests were completed, the data showed that the winglets provided a 7 percent improvement in range over the standard KC-135. The obvious economic advantage at a time of high fuel costs caused winglets to be adopted on business jets, airliners, and heavy military transports.

Inhibition of inflammatory gene expression in keratinocytes using a composition containing carnitine, thioctic Acid and saw palmetto extract.

PubMed

Chittur, Sridar; Parr, Brian; Marcovici, Geno

2011-01-01

Chronic inflammation of the hair follicle (HF) is considered a contributing factor in the pathogenesis of androgenetic alopecia (AGA). Previously, we clinically tested liposterolic extract of Serenoa repens (LSESr) and its glycoside, β-sitosterol, in subjects with AGA and showed a highly positive response to treatment. In this study, we sought to determine whether blockade of inflammation using a composition containing LSESr as well as two anti-inflammatory agents (carnitine and thioctic acid) could alter the expression of molecular markers of inflammation in a well-established in vitro system. Using a well-validated assay representative of HF keratinocytes, specifically, stimulation of cultured human keratinocyte cells in vitro, we measured changes in gene expression of a spectrum of well-known inflammatory markers. Lipopolysaccharide (LPS) provided an inflammatory stimulus. In particular, we found that the composition effectively suppressed LPS-activated gene expression of chemokines, including CCL17, CXCL6 and LTB(4) associated with pathways involved in inflammation and apoptosis. Our data support the hypothesis that the test compound exhibits anti-inflammatory characteristics in a well-established in vitro assay representing HF keratinocyte gene expression. These findings suggest that 5-alpha reductase inhibitors combined with blockade of inflammatory processes could represent a novel two-pronged approach in the treatment of AGA with improved efficacy over current modalities.

RA Construction KC, LLC Information Sheet

EPA Pesticide Factsheets

RA Construction KC, LLC (the Company) is located in Gladstone, Missouri. The settlement involves renovation activities conducted at a property constructed prior to 1978, located in Kansas City, Missouri.

Chemokines, macrophage inflammatory protein-2 and stromal cell-derived factor-1{alpha}, suppress amyloid {beta}-induced neurotoxicity

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

Raman, Dayanidhi; Milatovic, Snjezana-Zaja; Milatovic, Dejan

2011-11-15

Alzheimer's disease (AD) is characterized by a progressive cognitive decline and accumulation of neurotoxic oligomeric peptides amyloid-{beta} (A{beta}). Although the molecular events are not entirely known, it has become evident that inflammation, environmental and other risk factors may play a causal, disruptive and/or protective role in the development of AD. The present study investigated the ability of the chemokines, macrophage inflammatory protein-2 (MIP-2) and stromal cell-derived factor-1{alpha} (SDF-1{alpha}), the respective ligands for chemokine receptors CXCR2 and CXCR4, to suppress A{beta}-induced neurotoxicity in vitro and in vivo. Pretreatment with MIP-2 or SDF-1{alpha} significantly protected neurons from A{beta}-induced dendritic regression and apoptosismore » in vitro through activation of Akt, ERK1/2 and maintenance of metalloproteinase ADAM17 especially with SDF-1{alpha}. Intra-cerebroventricular (ICV) injection of A{beta} led to reduction in dendritic length and spine density of pyramidal neurons in the CA1 area of the hippocampus and increased oxidative damage 24 h following the exposure. The A{beta}-induced morphometric changes of neurons and increase in biomarkers of oxidative damage, F{sub 2}-isoprostanes, were significantly inhibited by pretreatment with the chemokines MIP-2 or SDF-1{alpha}. Additionally, MIP-2 or SDF-1{alpha} was able to suppress the aberrant mislocalization of p21-activated kinase (PAK), one of the proteins involved in the maintenance of dendritic spines. Furthermore, MIP-2 also protected neurons against A{beta} neurotoxicity in CXCR2-/- mice, potentially through observed up regulation of CXCR1 mRNA. Understanding the neuroprotective potential of chemokines is crucial in defining the role for their employment during the early stages of neurodegeneration. -- Research highlights: Black-Right-Pointing-Pointer Neuroprotective ability of the chemokines MIP2 and CXCL12 against A{beta} toxicity. Black

Mesenchymal stem cell-conditioned medium accelerates skin wound healing: An in vitro study of fibroblast and keratinocyte scratch assays

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

Walter, M.N.M.; School of Life and Health Science, Aston University, Aston Triangle, Birmingham, B4 7EJ; Wright, K.T.

2010-04-15

We have used in vitro scratch assays to examine the relative contribution of dermal fibroblasts and keratinocytes in the wound repair process and to test the influence of mesenchymal stem cell (MSC) secreted factors on both skin cell types. Scratch assays were established using single cell and co-cultures of L929 fibroblasts and HaCaT keratinocytes, with wound closure monitored via time-lapse microscopy. Both in serum supplemented and serum free conditions, wound closure was faster in L929 fibroblast than HaCaT keratinocyte scratch assays, and in co-culture the L929 fibroblasts lead the way in closing the scratches. MSC-CM generated under serum free conditionsmore » significantly enhanced the wound closure rate of both skin cell types separately and in co-culture, whereas conditioned medium from L929 or HaCaT cultures had no significant effect. This enhancement of wound closure in the presence of MSC-CM was due to accelerated cell migration rather than increased cell proliferation. A number of wound healing mediators were identified in MSC-CM, including TGF-{beta}1, the chemokines IL-6, IL-8, MCP-1 and RANTES, and collagen type I, fibronectin, SPARC and IGFBP-7. This study suggests that the trophic activity of MSC may play a role in skin wound closure by affecting both dermal fibroblast and keratinocyte migration, along with a contribution to the formation of extracellular matrix.« less

Mesenchymal stem cell-conditioned medium accelerates skin wound healing: an in vitro study of fibroblast and keratinocyte scratch assays.

PubMed

Walter, M N M; Wright, K T; Fuller, H R; MacNeil, S; Johnson, W E B

2010-04-15

We have used in vitro scratch assays to examine the relative contribution of dermal fibroblasts and keratinocytes in the wound repair process and to test the influence of mesenchymal stem cell (MSC) secreted factors on both skin cell types. Scratch assays were established using single cell and co-cultures of L929 fibroblasts and HaCaT keratinocytes, with wound closure monitored via time-lapse microscopy. Both in serum supplemented and serum free conditions, wound closure was faster in L929 fibroblast than HaCaT keratinocyte scratch assays, and in co-culture the L929 fibroblasts lead the way in closing the scratches. MSC-CM generated under serum free conditions significantly enhanced the wound closure rate of both skin cell types separately and in co-culture, whereas conditioned medium from L929 or HaCaT cultures had no significant effect. This enhancement of wound closure in the presence of MSC-CM was due to accelerated cell migration rather than increased cell proliferation. A number of wound healing mediators were identified in MSC-CM, including TGF-beta1, the chemokines IL-6, IL-8, MCP-1 and RANTES, and collagen type I, fibronectin, SPARC and IGFBP-7. This study suggests that the trophic activity of MSC may play a role in skin wound closure by affecting both dermal fibroblast and keratinocyte migration, along with a contribution to the formation of extracellular matrix. Copyright 2010 Elsevier Inc. All rights reserved.

Elevated expression of platelet-derived chemokines in patients with antiphospholipid syndrome.

PubMed

Patsouras, Markos D; Sikara, Marina P; Grika, Eleftheria P; Moutsopoulos, Haralampos M; Tzioufas, Athanasios G; Vlachoyiannopoulos, Panayiotis G

2015-12-01

Platelet factor 4 tetramers (CXCL4 chemokine) form complexes with β2glycoprotein I (β2GPI), recognized by anti-β2GPI antibodies leading to platelet activation in antiphospholipid syndrome (APS), either primary (PAPS) or secondary (SAPS). Increased plasma levels of CXCL4 may favor this process; therefore we measured plasma levels of CXCL4, a CXCL4 variant (CXCL4L1) and as controls, platelet-derived chemokines CXCL7 (NAP-2) and CCL5 (RANTES), in APS, and disease controls such as patients with systemic lupus erythematosus (SLE) coronary artery disease (CAD) and healthy donors (HDs). Plasma samples and platelets were isolated from patients with APS (n = 87), SLE (n = 29), CAD (n = 14) and 54 HDs. Plasma levels of CXCL4, CXCL4L1, CXCL7 and CCL5 as well as intracellular platelet CXCL4 and CXCL4L1 were measured using ELISA. Platelet CXCL4 and CXCL4L1 RNA levels were determined by RT-PCR. CXCL4, CXCL7 (NAP-2) and CCL5 (RANTES) plasma levels were significantly higher in patients with APS compared to both control groups (SLE, CAD) and HDs. CXCL4L1 plasma levels were also significantly higher in APS than in SLE and HDs, but lower from that of CAD patients. Statistically significant concordance was detected between CXCL4 and CXCL7 (p < 0.0001) or CCL5 (p < 0.0001) plasma levels in patients with APS, either PAPS or SAPS. CXCL4L1 plasma levels were inversely correlated with CXCL4 (P = 0.0027), CXCL7 (p = 0.012) and CCL5 (p = 0.023) in PAPS and positively with CXCL4 (p = 0.0191), CCL5 (p < 0.0001) and CXCL7 (P < 0.0001), in SAPS. Levels of CXCL4, CXCL4L1, CXCL7 and CCL5 were divided in "high" (exceeding a level defined as the mean of HDs and 3 SD) and "low" (below this level); The "CXCL4L1 high" group was characterized by increased IgG aCL, (p = 0.0215), double antibody positivity (either aCL or anti-β2GPI plus LA), (p = 0.0277), triple antibody positivity (aCL plus anti-β2GPI plus LA), (p = 0.0073) and thrombocytopenia (p = 0.0061), as well as with at least 1 thrombotic

Keratinocyte-melanocyte interactions during melanosome transfer.

PubMed

Seiberg, M

2001-08-01

The epidermal-melanin unit is composed of one melanocyte and approximately 36 neighboring keratinocytes, working in synchrony to produce and distribute melanin. Melanin is synthesized in melanosomes, transferred to the dendrite tips, and translocated into keratinocytes, forming caps over the keratinocyte nuclei. The molecular and cellular mechanisms involved in melanosome transfer and the keratinocyte-melanocyte interactions required for this process are not yet completely understood. Suggested mechanisms of melanosome transfer include melanosome release and endocytosis, direct inoculation ('injection'), keratinocyte-melanocyte membrane fusion, and phagocytosis. Studies of the keratinocyte receptor protease-activated receptor-2 (PAR-2) support the phagocytosis theory. PAR-2 controls melanosome ingestion and phagocytosis by keratinocytes and exerts a regulatory role in skin pigmentation. Modulation of PAR-2 activity can enhance or decrease melanosome transfer and affects pigmentation only when there is keratinocyte-melanocyte contact. Moreover, PAR-2 is induced by UV irradiation and inhibition of PAR-2 activation results in the prevention of UVB-induced tanning. The role of PAR-2 in mediating UV-induced responses remains to be elucidated.

Chemokine and Chemokine Receptor Profiles in Metastatic Salivary Adenoid Cystic Carcinoma.

PubMed

Mays, Ashley C; Feng, Xin; Browne, James D; Sullivan, Christopher A

2016-08-01

To characterize the chemokine pattern in metastatic salivary adenoid cystic carcinoma (SACC). Real-time polymerase chain reaction (RT-PCR) was used to compare chemokine and chemokine receptor gene expression in two SACC cell lines: SACC-83 and SACC-LM (lung metastasis). Chemokines and receptor genes were then screened and their expression pattern characterized in human tissue samples of non-recurrent SACC and recurrent SACC with perineural invasion. Expression of chemokine receptors C5AR1, CCR1, CCR3, CCR6, CCR7, CCR9, CCR10, CXCR4, CXCR6, CXCR7, CCRL1 and CCRL2 were higher in SACC-83 compared to SACC-LM. CCRL1, CCBP2, CMKLR1, XCR1 and CXCR2 and 6 chemokine genes (CCL13, CCL27, CXCL14, CMTM1, CMTM2, CKLF) were more highly expressed in tissues of patients without tumor recurrence/perineural invasion compared to those with tumor recurrence. CCRL1 (receptor), CCL27, CMTM1, CMTM2, and CKLF (chemokine) genes were more highly expressed in SACC-83 and human tissues of patients without tumor recurrence/perineural invasion. CCRL1, CCL27, CMTM1, CMTM2 and CKLF may play important roles in the development of tumor metastases in SACC. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Keratinocyte growth factor and the expression of wound-healing-related genes in primary human keratinocytes from burn patients.

PubMed

Chomiski, Verônica; Gragnani, Alfredo; Bonucci, Jéssica; Correa, Silvana Aparecida Alves; Noronha, Samuel Marcos Ribeiro de; Ferreira, Lydia Masako

2016-08-01

To evaluate the effect of keratinocyte growth factor (KGF) treatment on the expression of wound-healing-related genes in cultured keratinocytes from burn patients. Keratinocytes were cultured and divided into 4 groups (n=4 in each group): TKB (KGF-treated keratinocytes from burn patients), UKB (untreated keratinocytes from burn patients), TKC (KGF-treated keratinocytes from controls), and UKC (untreated keratinocytes from controls). Gene expression analysis using quantitative polymerase chain reaction (qPCR) array was performed to compare (1) TKC versus UKC, (2) UKB versus UKC, (3) TKB versus UKC, (4) TKB versus UKB, (5) TKB versus TKC, and (6) UKB versus TKC. Comparison 1 showed one down-regulated and one up-regulated gene; comparisons 2 and 3 resulted in the same five down-regulated genes; comparison 4 had no significant difference in relative gene expression; comparison 5 showed 26 down-regulated and 7 up-regulated genes; and comparison 6 showed 25 down-regulated and 11 up-regulated genes. There was no differential expression of wound-healing-related genes in cultured primary keratinocytes from burn patients treated with keratinocyte growth factor.

KC-135 Survivability in a War in Europe

DTIC Science & Technology

1989-05-01

IIESEARCHlRPR KC-135 SURVIVA~BILITY IN4 A WA~R IN EUROPE 6T COL joHN EKWALL 3.989c ei-.T ..... , t =T’ p \\47 MR JIVERSI~r UAIRE s’rAT AIR FORCE ...MAWEIJL AIR FORCE BASbAB AIR WAR COLLEGE AIR UNIVERSITY KC-135 SURVIVABILITY IN A WAR IN EUROPE by John Ekwall Lieutenant Colonel, USAF A DEFENSE...ANALYTICAL STUDY SUBMITTED TO THE FACULTY IN FULLFILLMENT OF THE CURRICULUM REQUIREMENT Advisor: Colonel Frank W. Anderson, Jr. MAXWELL AIR FORCE BASE

Neuronal apoptotic signaling pathways probed and intervened by synthetically and modularly modified (SMM) chemokines.

PubMed

Choi, Won-Tak; Kaul, Marcus; Kumar, Santosh; Wang, Jun; Kumar, I M Krishna; Dong, Chang-Zhi; An, Jing; Lipton, Stuart A; Huang, Ziwei

2007-03-09

As the main coreceptors for human immunodeficiency virus type 1 (HIV-1) entry, CXCR4 and CCR5 play important roles in HIV-associated dementia (HAD). HIV-1 glycoprotein gp120 contributes to HAD by causing neuronal damage and death, either directly by triggering apoptotic pathways or indirectly by stimulating glial cells to release neurotoxins. Here, to understand the mechanism of CXCR4 or CCR5 signaling in neuronal apoptosis associated with HAD, we have applied synthetically and modularly modified (SMM)-chemokine analogs derived from natural stromal cell-derived factor-1alpha or viral macrophage inflammatory protein-II as chemical probes of the mechanism(s) whereby these SMM-chemokines prevent or promote neuronal apoptosis. We show that inherently neurotoxic natural ligands of CXCR4, such as stromal cell-derived factor-1alpha or viral macrophage inflammatory protein-II, can be modified to protect neurons from apoptosis induced by CXCR4-preferring gp120(IIIB), and that the inhibition of CCR5 by antagonist SMM-chemokines, unlike neuroprotective CCR5 natural ligands, leads to neurotoxicity by activating a p38 mitogen-activated protein kinase (MAPK)-dependent pathway. Furthermore, we discover distinct signaling pathways activated by different chemokine ligands that are either natural agonists or synthetic antagonists, thus demonstrating a chemical biology strategy of using chemically engineered inhibitors of chemokine receptors to study the signaling mechanism of neuronal apoptosis and survival.

The triterpenoid CDDO-imidazolide reduces immune cell infiltration and cytokine secretion in the KrasG12D;Pdx1-Cre (KC) mouse model of pancreatic cancer

PubMed Central

Leal, Ana S.; Sporn, Michael B.; Pioli, Patricia A.; Liby, Karen T.

2016-01-01

Because the 5-year survival rate for pancreatic cancer remains under 10%, new drugs are needed for the prevention and treatment of this devastating disease. Patients with chronic pancreatitis have a 12-fold higher risk of developing pancreatic cancer. LSL-KrasG12D/+;Pdx-1-Cre (KC) mice replicate the genetics, symptoms and histopathology found in human pancreatic cancer. Immune cells infiltrate into the pancreas of these mice and produce inflammatory cytokines that promote tumor growth. KC mice are particularly sensitive to the effects of lipopolysaccharide (LPS), as only 48% of KC mice survived an LPS challenge while 100% of wildtype (WT) mice survived. LPS also increased the percentage of CD45+ immune cells in the pancreas and immunosuppressive Gr1+ myeloid-derived suppressor cell in the spleen of these mice. The triterpenoid CDDO-imidazolide (CDDO-Im) not only reduced the lethal effects of LPS (71% survival) but also decreased the infiltration of CD45+ cells into the pancreas and the percentage of Gr1+ myeloid-derived suppressor cell in the spleen of KC mice 4–8 weeks after the initial LPS challenge. While the levels of inflammatory cytokine levels were markedly higher in KC mice versus WT mice challenged with LPS, CDDO-Im significantly decreased the production of IL-6, CCL-2, vascular endothelial growth factor and G-CSF in the KC mice. All of these cytokines are prognostic markers in pancreatic cancer or play important roles in the progression of this disease. Disrupting the inflammatory process with drugs such as CDDO-Im might be useful for preventing pancreatic cancer, especially in high-risk populations. PMID:27659181

AZD-4818, a chemokine CCR1 antagonist: WO2008103126 and WO2009011653.

PubMed

Norman, Peter

2009-11-01

The applications WO2008103126 and WO2009011653, respectively, claim: i) Combinations of a spirocyclic piperidine chemokine CCR1 antagonist with a corticosteroid, and their use for the treatment of asthma and chronic obstructive pulmonary disease. ii) Processes for the preparation of a spirocyclic piperidine derivative, a chemokine CCR1 antagonist. These applications point to the preferred compound being a development compound. The evidence for this compound being AZD-4818, a chemokine CCR1 antagonist that was in Phase II development for the treatment of chronic obstructive pulmonary disease, is reviewed in the light of these and earlier patents relating to it.

Transactivation of involucrin, a marker of differentiation in keratinocytes, by lens epithelium-derived growth factor (LEDGF).

PubMed

Kubo, E; Fatma, N; Sharma, P; Shinohara, T; Chylack, L T; Akagi, Y; Singh, D P

2002-07-26

Human involucrin (hINV), first appears in the cytosol of keratinocytes and ultimately cross-linked to membrane proteins via transglutaminase and forms a protective barrier as an insoluble envelope beneath the plasma membrane. Although the function and evolution of involucrin is known, the regulation of its gene expression is not well understood. An analysis of the hINV gene sequence, upstream of the transcription start site (-534 to +1 nt) revealed the presence of potential sites for binding of lens epithelium-derived growth factor (LEDGF); stress response element (STRE; A/TGGGGA/T) and heat shock element (HSE; nGAAn). We reported earlier that LEDGF activates stress-associated genes by binding to these elements and elevates cellular resistance to various stresses. Here, gel-shift and super-shift assays confirm the binding of LEDGF to the DNA fragments containing HSEs and STREs that are present in the involucrin gene promoter. Furthermore, hINV promoter linked to CAT reporter gene, cotransfected in human corneal simian virus 40-transformed keratinocytes (HCK), was transactivated by LEDGF significantly. In contrast, the activity of hINV promoter bearing mutations at the WT1 (containing HSE and STRE), WT2 (containing STRE) and WT3 (containing STRE) binding sites was diminished. In addition, in HCK cell over-expressing LEDGF, the levels of hINV mRNA and hINV protein are increased by four to five-fold. LEDGF is inducible to oxidants. Cells treated with 12-O-tetradecanoyl-phorbol-13-acetate (TPA), known to stimulate production of H(2)O(2), showed higher levels of LEDGF mRNA. Furthermore, our immunohistochemical studies revealed that hINV protein is found in the cytoplasm of HCK cells over-expressing LEDGF, but not detectable in the normal HCK cells or HCK cells transfected with vector. This regulation appears to be physiologically important, as over-expression of HCK with LEDGF increases the expression of the endogenous hINV gene and may provide new insight to understand

Attachment and growth of human keratinocytes in a serum-free environment.

PubMed

Gilchrest, B A; Calhoun, J K; Maciag, T

1982-08-01

Using a serum-free system, we have investigated the influence of human fibronectin (HFN) and selected growth factors (GF) on the attachment and growth of normal human keratinocytes in vitro. Single-cell suspensions of keratinocytes from near-confluent primary plates, plated on 5-10 microgram/cm2 HFN, showed approximately 30-40% attachment after 2-24 hours of incubation at 37 degrees C, compared with 4-6% attachment on uncoated platic plates. Percentage of attached cells was independent of seed density, tissue donor age, in vitro culture age, or medium composition, while subsequent cellular proliferation was strongly dependent on these factors. Keratinocytes grown on an adequate HFN matrix in a previously described hormone-supplemented medium (Maciag et al., 1981a) achieved four to eight population doubling over 7-12 days at densities greater than or equal to 104 cell/cm2. Removal of most GF individually from the medium had little or no effect on growth, while removal of epidermal growth factor (EGF) alone reduced growth by 30-35% and removal of bovine brain extract (BE) alone reduced growth by approximately 90%. Conversely, EGF alone in basal medium supported approximately 10% control growth, BE alone supported 30-40% control growth, and the combination of EGF and BE approximately 70%. In addition to its major effect on proliferation in this system, BE was necessary to preserve normal keratinocyte morphology and protein production. These findings expand earlier observations that HFN facilitates keratinocyte attachment in vitro and that a brain-derived extract can exert a major positive influence on cultured keratinocytes.

The cytoskeleton of Drosophila-derived Schneider line-1 and Kc23 cells undergoes significant changes during long-term culture

NASA Technical Reports Server (NTRS)

Schatten, H.; Hedrick, J.; Chakrabarti, A.

1998-01-01

Insect cell cultures derived from Drosophila melanogaster are increasingly being used as an alternative system to mammalian cell cultures, as they are amenable to genetic manipulation. Although Drosophila cells are an excellent tool for the study of genes and expression of proteins, culture conditions have to be considered in the interpretation of biochemical results. Our studies indicate that significant differences occur in cytoskeletal structure during the long-term culture of the Drosophila-derived cell lines Schneider Line-1 (S1) and Kc23. Scanning, transmission-electron, and immunofluorescence microscopy studies reveal that microfilaments, microtubules, and centrosomes become increasingly different during the culture of these cells from 24 h to 7-14 days. Significant cytoskeletal changes are observed at the cell surface where actin polymerizes into microfilaments, during the elongation of long microvilli. Additionally, long protrusions develop from the cell surface; these protrusions are microtubule-based and establish contact with neighboring cells. In contrast, the microtubule network in the interior of the cells becomes disrupted after four days of culture, resulting in altered transport of mitochondria. Microtubules and centrosomes are also affected in a small percent of cells during cell division, indicating an instability of centrosomes. Thus, the cytoskeletal network of microfilaments, microtubules, and centrosomes is affected in Drosophila cells during long-term culture. This implies that gene regulation and post-translational modifications are probably different under different culture conditions.

Epigenetic control of IL-23 expression in keratinocytes is important for chronic skin inflammation.

PubMed

Li, Hui; Yao, Qi; Mariscal, Alberto Garcia; Wu, Xudong; Hülse, Justus; Pedersen, Esben; Helin, Kristian; Waisman, Ari; Vinkel, Caroline; Thomsen, Simon Francis; Avgustinova, Alexandra; Benitah, Salvador Aznar; Lovato, Paola; Norsgaard, Hanne; Mortensen, Mette Sidsel; Veng, Lone; Rozell, Björn; Brakebusch, Cord

2018-04-12

The chronic skin inflammation psoriasis is crucially dependent on the IL-23/IL-17 cytokine axis. Although IL-23 is expressed by psoriatic keratinocytes and immune cells, only the immune cell-derived IL-23 is believed to be disease relevant. Here we use a genetic mouse model to show that keratinocyte-produced IL-23 is sufficient to cause a chronic skin inflammation with an IL-17 profile. Furthermore, we reveal a cell-autonomous nuclear function for the actin polymerizing molecule N-WASP, which controls IL-23 expression in keratinocytes by regulating the degradation of the histone methyltransferases G9a and GLP, and H3K9 dimethylation of the IL-23 promoter. This mechanism mediates the induction of IL-23 by TNF, a known inducer of IL-23 in psoriasis. Finally, in keratinocytes of psoriatic lesions a decrease in H3K9 dimethylation correlates with increased IL-23 expression, suggesting relevance for disease. Taken together, our data describe a molecular pathway where epigenetic regulation of keratinocytes can contribute to chronic skin inflammation.

A study of chemokines, chemokine receptors and interleukin-6 in patients with panic disorder, personality disorders and their co-morbidity.

PubMed

Ogłodek, Ewa A; Szota, Anna M; Just, Marek J; Szromek, Adam R; Araszkiewicz, Aleksander

2016-08-01

Stress may induce inflammatory changes in the immune system and activate pro-inflammatory cytokines and their receptors by activating the hypothalamic-pituitary-adrenal axis. 460 hospitalized patients with panic disorders (PD) and/or personality disorders (P) were studied. The study group comprised subjects with PD, avoidant personality disorder (APD), borderline personality disorder (BPD), obsessive-compulsive personality disorder (OCPD), and concomitant (PD+APD; PD+BPD; PD+OCPD). Each study group consisted of 60 subjects (30 females and 30 males). The control group included 20 females and 20 males without any history of mental disorder. ELISA was used to assess the levels of chemokines: CCL-5/RANTES (regulated on activation, normal T-cell expressed and secreted), CXCL-12/SDF-1 (stromal derived factor), their receptors CXCR-5 (C-C chemokine receptor type-5), CXCR-4 (chemokine C-X-C motif receptor-4), and IL-6. Statistically significant differences in the levels of CCL-5 and CCR-5 were revealed between all study groups. The greatest differences were found between the groups with PD+OCPD and PD+APD. Moreover, concomitance of PD with P significantly increased the level of chemokines and their receptors in all study groups versus the subjects with P alone. The results of the study show differences between the groups. To be specific, inflammatory markers were more elevated in the study groups than the controls. Therefore, chemokines and chemokine receptors may be used as inflammatory markers in patients with PD co-existent with P to indicate disease severity. PD was found to be a factor in maintaining inflammatory activity in the immune system in patients with P. Copyright © 2016 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

The triterpenoid CDDO-imidazolide reduces immune cell infiltration and cytokine secretion in the KrasG12D;Pdx1-Cre (KC) mouse model of pancreatic cancer.

PubMed

Leal, Ana S; Sporn, Michael B; Pioli, Patricia A; Liby, Karen T

2016-12-01

Because the 5-year survival rate for pancreatic cancer remains under 10%, new drugs are needed for the prevention and treatment of this devastating disease. Patients with chronic pancreatitis have a 12-fold higher risk of developing pancreatic cancer. LSL-Kras G12D/+ ;Pdx-1-Cre (KC) mice replicate the genetics, symptoms and histopathology found in human pancreatic cancer. Immune cells infiltrate into the pancreas of these mice and produce inflammatory cytokines that promote tumor growth. KC mice are particularly sensitive to the effects of lipopolysaccharide (LPS), as only 48% of KC mice survived an LPS challenge while 100% of wildtype (WT) mice survived. LPS also increased the percentage of CD45+ immune cells in the pancreas and immunosuppressive Gr1+ myeloid-derived suppressor cell in the spleen of these mice. The triterpenoid CDDO-imidazolide (CDDO-Im) not only reduced the lethal effects of LPS (71% survival) but also decreased the infiltration of CD45+ cells into the pancreas and the percentage of Gr1+ myeloid-derived suppressor cell in the spleen of KC mice 4-8 weeks after the initial LPS challenge. While the levels of inflammatory cytokine levels were markedly higher in KC mice versus WT mice challenged with LPS, CDDO-Im significantly decreased the production of IL-6, CCL-2, vascular endothelial growth factor and G-CSF in the KC mice. All of these cytokines are prognostic markers in pancreatic cancer or play important roles in the progression of this disease. Disrupting the inflammatory process with drugs such as CDDO-Im might be useful for preventing pancreatic cancer, especially in high-risk populations. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

78 FR 77118 - KC Small Hydro, LLC; Notice of Amended Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-20

..., Motions To Intervene, and Competing Applications On May 28, 2013, KC Scoby Hydro, LLC, filed an... 28, 2013, application and sent an acceptance letter to KC Scoby Hydro, LLC. Subsequently, On October 28, 2013, KC Scoby Hydro, LLC, amended its preliminary permit application to change its name to KC...

Analysis of the temporal expression of chemokines and chemokine receptors during experimental granulomatous inflammation: role and expression of MIP-1α and MCP-1

PubMed Central

Carollo, Maria; Hogaboam, Cory M; Kunkel, Stephen L; Delaney, Stephen; Christie, Mark I; Perretti, Mauro

2001-01-01

Chemokine expression and function was monitored in an experimental model of granulomatous tissue formation after injection of croton oil in complete Freund's adjuvant (CO/CFA) into mouse dorsal air-pouches up to 28 days. In the first week, mast cell degranulation and leukocyte influx (mononuclear cell, MNC, and polymorphonuclear cell, PMN) were associated with CXCR2, KC and macrophage inflammatory protein (MIP)-2 mRNA expression, as determined by TaqMan® reverse transcriptase-polymerase chain reaction. KC (∼400 pg mg protein−1, n=12) and MIP-2 (∼800 pg mg protein−1, n=12) proteins peaked at day 7, together with myeloperoxidase (MPO) activity. Highest MIP-1α (>1 ng mg protein−1, n=12) levels were measured at day 3. After day 7, a gradual increase in CCR2 and CCR5 mRNA, monocyte chemoattractant protein (MCP)-1 mRNA and protein expression was measured. MCP-1 protein peaked at day 21 (∼150 pg mg protein−1, n=12) and was predominantly expressed by mast cells. A gradual increase in N-acetyl-β-D-glucosaminidase (NAG) activity (maximal at 28 days) was also measured. An antiserum against MIP-1α did not modify the inflammatory response measured at day 7 (except for a 50% reduction in MIP-1α levels), but provoked a significant increase in MPO, NAG and MCP-1 levels as measured at day 21 (n=6, P<0.05). An antiserum to MCP-1 reduced NAG activity at day 21 but increased MPO activity values (n=8, P<0.05). In conclusion, we have shown that CO/CFA initiates a complex inflammatory reaction in which initial expression of MIP-1α serves a protective role whereas delayed expression of MCP-1 seems to have a genuine pro-inflammatory role. PMID:11704636

Testing Microgravity Flight Hardware Concepts on the NASA KC-135

NASA Technical Reports Server (NTRS)

Motil, Susan M.; Harrivel, Angela R.; Zimmerli, Gregory A.

2001-01-01

This paper provides an overview of utilizing the NASA KC-135 Reduced Gravity Aircraft for the Foam Optics and Mechanics (FOAM) microgravity flight project. The FOAM science requirements are summarized, and the KC-135 test-rig used to test hardware concepts designed to meet the requirements are described. Preliminary results regarding foam dispensing, foam/surface slip tests, and dynamic light scattering data are discussed in support of the flight hardware development for the FOAM experiment.

Melanosomes are transferred from melanocytes to keratinocytes through the processes of packaging, release, uptake, and dispersion.

PubMed

Ando, Hideya; Niki, Yoko; Ito, Masaaki; Akiyama, Kaoru; Matsui, Mary S; Yarosh, Daniel B; Ichihashi, Masamitsu

2012-04-01

Recent studies have described the role of shedding vesicles as physiological conveyers of intracellular components between neighboring cells. Here we report that melanosomes are one example of shedding vesicle cargo, but are processed by a previously unreported mechanism. Pigment globules were observed to be connected to the filopodia of melanocyte dendrites, which have previously been shown to be conduits for melanosomes. Pigment globules containing multiple melanosomes were released from various areas of the dendrites of normal human melanocytes derived from darkly pigmented skin. The globules were then captured by the microvilli of normal human keratinocytes, also derived from darkly pigmented skin, which incorporated them in a protease-activated receptor-2 (PAR-2)-dependent manner. After the pigment globules were ingested by the keratinocytes, the membrane that surrounded each melanosome cluster was gradually degraded, and the individual melanosomes then spread into the cytosol and were distributed primarily in the perinuclear area of each keratinocyte. These results suggest a melanosome transfer pathway wherein melanosomes are transferred from melanocytes to keratinocytes via the shedding vesicle system. This packaging system generates pigment globules containing multiple melanosomes in a unique manner.

Chemical allergens stimulate human epidermal keratinocytes to produce lymphangiogenic vascular endothelial growth factor

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

Bae, Ok-Nam; Ahn, Seyeon; Jin, Sun Hee

2015-03-01

Allergic contact dermatitis (ACD) is a cell-mediated immune response that involves skin sensitization in response to contact with various allergens. Angiogenesis and lymphangiogenesis both play roles in the allergic sensitization process. Epidermal keratinocytes can produce vascular endothelial growth factor (VEGF) in response to UV irradiation and during wound healing. However, the effect of haptenic chemical allergens on the VEGF production of human keratinocytes, which is the primary contact site of toxic allergens, has not been thoroughly researched. We systematically investigated whether immune-regulatory cytokines and chemical allergens would lead to the production of VEGF in normal human keratinocytes (NHKs) in culture.more » VEGF production significantly increased when NHKs were treated with IFNγ, IL-1α, IL-4, IL-6, IL-17A, IL-22 or TNFα. Among the human sensitizers listed in the OECD Test Guideline (TG) 429, we found that CMI/MI, DNCB, 4-phenylenediamine, cobalt chloride, 2-mercaptobenzothiazole, citral, HCA, cinnamic alcohol, imidazolidinyl urea and nickel chloride all significantly upregulated VEGF production in NHKs. In addition, common human haptenic allergens such as avobenzone, formaldehyde and urushiol, also induced the keratinocyte-derived VEGF production. VEGF upregulation by pro-inflammatory stimuli, IFNγ, DNCB or formaldehyde is preceded by the production of IL-8, an acute inflammatory phase cytokine. Lymphangiogenic VEGF-C gene transcription was significantly increased when NHKs were treated with formaldehyde, DNCB or urushiol, while transcription of VEGF-A and VEGF-B did not change. Therefore, the chemical allergen-induced VEGF upregulation is mainly due to the increase in lymphangiogenic VEGF-C transcription in NHKs. These results suggest that keratinocyte-derived VEGF may regulate the lymphangiogenic process during the skin sensitization process of ACD. - Highlights: • Pro-inflammatory cytokines induced VEGF production in normal

Beta genus papillomaviruses and skin cancer.

PubMed

Howley, Peter M; Pfister, Herbert J

2015-05-01

A role for the beta genus HPVs in keratinocyte carcinoma (KC) remains to be established. In this article we examine the potential role of the beta HPVs in cancer revealed by the epidemiology associating these viruses with KC and supported by oncogenic properties of the beta HPV proteins. Unlike the cancer associated alpha genus HPVs, in which transcriptionally active viral genomes are invariably found associated with the cancers, that is not the case for the beta genus HPVs and keratinocyte carcinomas. Thus a role for the beta HPVs in KC would necessarily be in the carcinogenesis initiation and not in the maintenance of the tumor. Copyright © 2015 Elsevier Inc. All rights reserved.

Genetic Phagocyte NADPH Oxidase Deficiency Enhances Nonviable Candida albicans-Induced Inflammation in Mouse Lungs.

PubMed

Endo, Daiki; Fujimoto, Kenta; Hirose, Rika; Yamanaka, Hiroko; Homme, Mizuki; Ishibashi, Ken-Ichi; Miura, Noriko; Ohno, Naohito; Aratani, Yasuaki

2017-02-01

Patients with chronic granulomatous disease (CGD) have mutated phagocyte NADPH oxidase, resulting in reduced production of reactive oxygen species (ROS). While the mechanism underlying hyperinfection in CGD is well understood, the basis for inflammatory disorders that arise in the absence of evident infection has not been fully explained. This study aimed to evaluate the effect of phagocyte NADPH oxidase deficiency on lung inflammation induced by nonviable Candida albicans (nCA). Mice deficient in this enzyme (CGD mice) showed more severe neutrophilic pneumonia than nCA-treated wild-type mice, which exhibited significantly higher lung concentrations of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and keratinocyte-derived chemokine (KC). Neutralization of these proinflammatory mediators significantly reduced neutrophil infiltration. In vitro, production of IL-1β and TNF-α from neutrophils and that of KC from macrophages was enhanced in nCA-stimulated neutrophils from CGD mice. Expression of IL-1β mRNA was higher in the stimulated CGD neutrophils than in the stimulated wild-type cells, concomitant with upregulation of nuclear factor (NF)-κB and its upstream regulator extracellular-signal regulated kinase (ERK) 1/2. Pretreatment with an NADPH oxidase inhibitor significantly enhanced IL-1β production in the wild-type neutrophils stimulated with nCA. These results suggest that lack of ROS production because of NADPH oxidase deficiency results in the production of higher levels of proinflammatory mediators from neutrophils and macrophages, which may at least partly contribute to the exacerbation of nCA-induced lung inflammation in CGD mice.

Human Keratinocytes Are Vanilloid Resistant

PubMed Central

Pecze, László; Szabó, Kornélia; Széll, Márta; Jósvay, Katalin; Kaszás, Krisztián; Kúsz, Erzsébet; Letoha, Tamás; Prorok, János; Koncz, István; Tóth, András; Kemény, Lajos; Vizler, Csaba; Oláh, Zoltán

2008-01-01

Background Use of capsaicin or resiniferatoxin (RTX) as analgesics is an attractive therapeutic option. RTX opens the cation channel inflammatory pain/vanilloid receptor type 1 (TRPV1) permanently and selectively removes nociceptive neurons by Ca2+-cytotoxicity. Paradoxically, not only nociceptors, but non-neuronal cells, including keratinocytes express full length TRPV1 mRNA, while patient dogs and experimental animals that underwent topical treatment or anatomically targeted molecular surgery have shown neither obvious behavioral, nor pathological side effects. Methods To address this paradox, we assessed the vanilloid sensitivity of the HaCaT human keratinocyte cell line and primary keratinocytes from skin biopsies. Results Although both cell types express TRPV1 mRNA, neither responded to vanilloids with Ca2+-cytotoxicity. Only ectopic overproduction of TRPV1 rendered HaCaT cells sensitive to low doses (1–50 nM) of vanilloids. The TRPV1-mediated and non-receptor specific Ca2+-cytotoxity ([RTX]>15 µM) could clearly be distinguished, thus keratinocytes were indeed resistant to vanilloid-induced, TRPV1-mediated Ca2+-entry. Having a wider therapeutic window than capsaicin, RTX was effective in subnanomolar range, but even micromolar concentrations could not kill human keratinocytes. Keratinocytes showed orders of magnitudes lower TRPV1 mRNA level than sensory ganglions, the bona fide therapeutic targets in human pain management. In addition to TRPV1, TRPV1b, a dominant negative splice variant was also noted in keratinocytes. Conclusion TRPV1B expression, together with low TRPV1 expression, may explain the vanilloid paradox: even genuinely TRPV1 mRNA positive cells can be spared with therapeutic (up to micromolar) doses of RTX. This additional safety information might be useful for planning future human clinical trials. PMID:18852901

Sumoylation Dynamics During Keratinocyte Differentiation

PubMed Central

Deyrieux, Adeline F.; Rosas-Acosta, Germán; Ozbun, Michelle A.; Wilson, Van G.

2012-01-01

Summary SUMO modification regulates the activity of numerous transcription factors that have a direct role in cell cycle progression, apoptosis, cellular proliferation, and development, but its role in differentiation processes is less clear. Keratinocyte differentiation requires the coordinated activation of a series of transcription factors, and as several critical keratinocyte transcription factors are known to be SUMO substrates, we investigated the role of sumoylation in keratinocyte differentiation. In a human keratinocyte cell line model (HaCaT cells), calcium-induced differentiation led to the transient and coordinated transcriptional activation of the genes encoding critical sumoylation system components, including SAE1, SAE2, Ubc9, SENP1, Miz-1 (PIASxβ), SUMO2, and SUMO3. The increased gene expression resulted in higher levels of the respective proteins and changes in the pattern of sumoylated substrate proteins during the differentiation process. Similar to the HaCaT results, stratified human foreskin keratinocytes showed an upregulation of Ubc9 in the suprabasal layers. Lastly, abrogation of sumoylation by Gam1 expression severely disrupted normal HaCaT differentiation, consistent with an important role for sumoylation in the proper progression of this biological process. PMID:17164289

Chemokines: novel targets for breast cancer metastasis

PubMed Central

Ali, Simi; Lazennec, Gwendal

2007-01-01

Recent studies have highlighted the possible involvement of chemokines and their receptors in breast cancer progression and metastasis. Chemokines and their receptors constitute a superfamily of signalling factors whose prognosis value in breast cancer progression remains unclear. We will examine here the expression pattern of chemokines and their receptors in mammary gland physiology and carcinogenesis. The nature of the cells producing chemokines or harboring chemokine receptors appears to be crucial in certain conditions for example, the infiltration of the primary tumor by leukocytes and angiogenesis. In addition, chemokines, their receptors and the interaction with glycosaminoglycan (GAGs) are key players in the homing of cancer cells to distant metastasis sites. Several lines of evidence, including in vitro and in vivo models, suggest that the mechanism of action of chemokines in cancer development involves the modulation of proliferation, apoptosis, invasion, leukocyte recruitment or angiogenesis. Furthermore, we will discuss the regulation of chemokine network in tumor neovascularity by decoy receptors. The reasons accounting for the deregulation of chemokines and chemokine receptors expression in breast cancer are certainly crucial for the comprehension of chemokine role in breast cancer and are in several cases linked to estrogen receptor status. The targeting of chemokines and chemokine receptors by antibodies, small molecule antagonists, viral chemokine binding proteins and heparins appears as promising tracks to develop therapeutic strategies. Thus there is significant interest in developing strategies to antagonize the chemokine function, and an opportunity to interfere with metastasis, the leading cause of death in most patients. PMID:17717637

Repeated measurement of nasal lavage fluid chemokines in school-age children with asthma.

PubMed

Noah, Terry L; Tudor, Gail E; Ivins, Sally S; Murphy, Paula C; Peden, David B; Henderson, Frederick W

2006-02-01

Inflammatory processes at the mucosal surface may play a role in maintenance of asthma pathophysiology. Cross-sectional studies in asthmatic patients suggest that chemokines such as interleukin 8 (IL-8) are overproduced by respiratory epithelium. To test the hypothesis that chemokine levels are persistently elevated in the respiratory secretions of asthmatic children at a stable baseline. We measured nasal lavage fluid (NLF) levels of chemokines and other mediators at 3- to 4-month intervals in a longitudinal study of asthmatic children, with nonasthmatic siblings as controls. In a linear mixed-model analysis, both family and day of visit had significant effects on nasal mediators. Thus, data for 12 asthmatic-nonasthmatic sibling pairs who had 3 or more same-day visits were analyzed separately. For sibling pairs, median eosinophil cationic protein levels derived from serial measurements in NLF were elevated in asthmatic patients compared with nonasthmatic patients, with a near-significant tendency for elevation of total protein and eotaxin levels as well. However, no significant differences were found for IL-8 or several other chemokines. Ratios of IL-13 or IL-5 to interferon-gamma released by house dust mite antigen-stimulated peripheral blood mononuclear cells, tested on a single occasion, were significantly increased for asthmatic patients. Substantial temporal and family-related variability exists in nasal inflammation in asthmatic children. Although higher levels of eosinophil cationic protein are usually present in NLF of patients with stable asthma compared with patients without asthma, chemokines other than eotaxin are not consistently increased. Eosinophil activation at the mucosal surface is a more consistent predictor of asthmatic symptoms than nonspecific elevation of epithelium-derived inflammatory chemokine levels.

Active Shaping of Chemokine Gradients by Atypical Chemokine Receptors: A 4D Live-Cell Imaging Migration Assay.

PubMed

Werth, Kathrin; Förster, Reinhold

2016-01-01

Diffusion of chemokines away from their site of production results in the passive formation of chemokine gradients. We have recently shown that chemokine gradients can also be formed in an active manner, namely by atypical chemokine receptors (ACKRs) that scavenge chemokines locally. Here, we describe an advanced method that allows the visualization of leukocyte migration in a three-dimensional environment along a chemokine gradient that is actively established by cells expressing an ACKR. Initially developed to visualize the migration of dendritic cells along gradients of CCL19 or CCL21 that were actively shaped by an ACKR4-expressing cell line, we expect that this chamber system can be exploited to study many other combinations of atypical and conventional chemokine receptor-expressing cells. © 2016 Elsevier Inc. All rights reserved.

Structural Analysis of Chemokine Receptor–Ligand Interactions

PubMed Central

2017-01-01

This review focuses on the construction and application of structural chemokine receptor models for the elucidation of molecular determinants of chemokine receptor modulation and the structure-based discovery and design of chemokine receptor ligands. A comparative analysis of ligand binding pockets in chemokine receptors is presented, including a detailed description of the CXCR4, CCR2, CCR5, CCR9, and US28 X-ray structures, and their implication for modeling molecular interactions of chemokine receptors with small-molecule ligands, peptide ligands, and large antibodies and chemokines. These studies demonstrate how the integration of new structural information on chemokine receptors with extensive structure–activity relationship and site-directed mutagenesis data facilitates the prediction of the structure of chemokine receptor–ligand complexes that have not been crystallized. Finally, a review of structure-based ligand discovery and design studies based on chemokine receptor crystal structures and homology models illustrates the possibilities and challenges to find novel ligands for chemokine receptors. PMID:28165741

Atypical chemokine receptors in cancer: friends or foes?

PubMed

Massara, Matteo; Bonavita, Ornella; Mantovani, Alberto; Locati, Massimo; Bonecchi, Raffaella

2016-06-01

The chemokine system is a fundamental component of cancer-related inflammation involved in all stages of cancer development. It controls not only leukocyte infiltration in primary tumors but also angiogenesis, cancer cell proliferation, and migration to metastatic sites. Atypical chemokine receptors are a new, emerging class of regulators of the chemokine system. They control chemokine bioavailability by scavenging, transporting, or storing chemokines. They can also regulate the activity of canonical chemokine receptors with which they share the ligands by forming heterodimers or by modulating their expression levels or signaling activity. Here, we summarize recent results about the role of these receptors (atypical chemokine receptor 1/Duffy antigen receptor for chemokine, atypical chemokine receptor 2/D6, atypical chemokine receptor 3/CXC-chemokine receptor 7, and atypical chemokine receptor 4/CC-chemokine receptor-like 1) on the tumorigenesis process, indicating that their effects are strictly dependent on the cell type on which they are expressed and on their coexpression with other chemokine receptors. Indeed, atypical chemokine receptors inhibit tumor growth and progression through their activity as negative regulators of chemokine bioavailability, whereas, on the contrary, they can promote tumorigenesis when they regulate the signaling of other chemokine receptors, such as CXC-chemokine receptor 4. Thus, atypical chemokine receptors are key components of the regulatory network of inflammation and immunity in cancer and may have a major effect on anti-inflammatory and immunotherapeutic strategies. © Society for Leukocyte Biology.

Th17 cell-mediated immune responses promote mast cell proliferation by triggering stem cell factor in keratinocytes

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

Cho, Kyung-Ah; Park, Minhwa; Kim, Yu-Hee

Although mast cells are traditionally thought to function as effector cells in allergic responses, they have increasingly been recognized as important regulators of various immune responses. Mast cells mature locally; thus, tissue-specific influences are important for promoting mast cell accumulation and survival in the skin and the gastrointestinal tract. In this study, we determined the effects of keratinocytes on mast cell accumulation during Th17-mediated skin inflammation. We observed increases in dermal mast cells in imiquimod-induced psoriatic dermatitis in mice accompanied by the expression of epidermal stem cell factor (SCF), a critical mast cell growth factor. Similar to mouse epidermal keratinocytes,more » SCF was highly expressed in the human HaCaT keratinocyte cell line following stimulation with IL−17. Further, keratinocytes promoted mast cell proliferation following stimulation with IL−17 in vitro. However, the effects of keratinocytes on mast cells were significantly diminished in the presence of anti−CD117 (stem cell factor receptor) blocking antibodies. Taken together, our results revealed that the Th17-mediated inflammatory environment promotes mast cell accumulation through keratinocyte-derived SCF. - Highlights: • Psoriasis-like skin inflammation increase dermal mast cells. • Keratinocyte produce stem cell factor in psoriasis-like skin inflammation. • Keratinocyte promote mast cell proliferation by stem cell factor dependent manner.« less

Shiga Toxin 2 and Lipopolysaccharide Induce Human Microvascular Endothelial Cells To Release Chemokines and Factors That Stimulate Platelet Function

PubMed Central

Guessous, Fadila; Marcinkiewicz, Marek; Polanowska-Grabowska, Renata; Kongkhum, Sudawadee; Heatherly, Daniel; Obrig, Tom; Gear, Adrian R. L.

2005-01-01

Shiga toxins (Stxs) produced by Shigella dysenteriae type 1 and enterohemorrhagic Escherichia coli are the most common cause of hemolytic-uremic syndrome (HUS). It is well established that vascular endothelial cells, mainly those located in the renal microvasculature, are targets for Stxs. The aim of the present research was to evaluate whether E. coli-derived Shiga toxin 2 (Stx2) incubated with human microvascular endothelial cells (HMEC-1) induces release of chemokines and other factors that might stimulate platelet function. HMEC-1 were exposed for 24 h in vitro to Stx2, lipopolysaccharide (LPS), or the Stx2-LPS combination, and chemokine production was assessed by immunoassay. More interleukin-8 was released than stromal cell-derived factor 1α (SDF-1α) or SDF-1β and RANTES. The Stx2-LPS combination potentiated chemokine release, but Stx2 alone caused more release of SDF-1α at 24 h than LPS or Stx2-LPS did. In the presence of low ADP levels, HMEC-1 supernatants activated platelet function assessed by classical aggregometry, single-particle counting, granule secretion, P-selectin exposure, and the formation of platelet-monocyte aggregates. Supernatants from HMEC-1 exposed only to Stx2 exhibited enhanced exposure of platelet P-selectin and platelet-THP-1 cell interactions. Blockade of platelet cyclooxygenase by indomethacin prevented functional activation. The chemokine RANTES enhanced platelet aggregation induced by SDF-1α, macrophage-derived chemokine, or thymus and activation-regulated chemokine in the presence of very low ADP levels. These data support the hypothesis that microvascular endothelial cells exposed to E. coli O157:H7-derived Stx2 and LPS release chemokines and other factors, which when combined with low levels of primary agonists, such as ADP, cause platelet activation and promote the renal thrombosis associated with HUS. PMID:16299328

Patented natural avocado sugar modulates the HBD-2 and HBD-3 expression in human keratinocytes through toll-like receptor-2 and ERK/MAPK activation.

PubMed

Paoletti, Iole; Buommino, Elisabetta; Fusco, Alessandra; Baudouin, Caroline; Msika, Philippe; Tufano, Maria Antonietta; Baroni, Adone; Donnarumma, Giovanna

2012-10-01

Keratinocytes stimulated by microbial organisms secrete not only a variety of cytokines, chemokines and growth factors, but also antimicrobial peptides such as beta-defensins (HBDs) such as HBD-2 and HBD-3. AV119, a patented blend of avocado sugar, triggers the up-regulation of HBD-2 in skin epithelia upon contact with AV119, but the signalling mechanisms involved are not completely understood. The purpose of this study was to determine if AV119 was able to induce also the expression of HBD-3 in human keratinocytes. In addition, the receptor and intracellular pathways involved in the AV119 up-regulation of HBD-2 and HBD-3 were investigated. Our results demonstrated that AV119 induces a significantly increase of the expression of HBD-3. In addition, the HBD-2 and HBD-3 AV119-induced gene expression and release are TLR-2 dependent. Finally, we demonstrated that AV119 induced ERK/MAPK phosphorylation in human keratinocytes, thus providing evidence that HBD-2 and HBD-3 secretion is through the same transductional pathway. The ability of AV119 to induce also HBD-3 may amplify its therapeutic potential against a broader spectrum of bacterial and yeast strains responsible for human skin disorders.

Suppression of lipopolysaccharide-stimulated cytokine/chemokine production in skin cells by sandalwood oils and purified α-santalol and β-santalol.

PubMed

Sharma, M; Levenson, C; Bell, R H; Anderson, S A; Hudson, J B; Collins, C C; Cox, M E

2014-06-01

Medicinally, sandalwood oil (SO) has been attributed with antiinflammatory properties; however, mechanism(s) for this activity have not been elucidated. To examine how SOs affect inflammation, cytokine antibody arrays and enzyme-linked immunosorbent assays were used to assess changes in production of cytokines and chemokines by co-cultured human dermal fibroblasts and neo-epidermal keratinocytes exposed to lipopolysaccharides and SOs from Western Australian and East Indian sandalwood trees or to the primary SO components, α-santalol and β-santalol. Lipopolysaccharides stimulated the release of 26 cytokines and chemokines, 20 of which were substantially suppressed by simultaneous exposure to either of the two sandalwood essential oils and to ibuprofen. The increased activity of East Indian SO correlated with increased santalol concentrations. Purified α-santalol and β-santalol equivalently suppressed production of five indicator cytokines/chemokines at concentrations proportional to the santalol concentrations of the oils. Purified α-santalol and β-santalol also suppressed lipopolysaccharide-induced production of the arachidonic acid metabolites, prostaglandin E2, and thromboxane B2, by the skin cell co-cultures. The ability of SOs to mimic ibuprofen non-steroidal antiinflammatory drugs that act by inhibiting cyclooxygenases suggests a possible mechanism for the observed antiinflammatory properties of topically applied SOs and provides a rationale for use in products requiring antiinflammatory effects. Copyright © 2013 John Wiley & Sons, Ltd.

Chemokines in tumor progression and metastasis

PubMed Central

Sarvaiya, Purvaba J.; Guo, Donna; Ulasov, Ilya; Gabikian, Patrik; Lesniak, Maciej S.

2013-01-01

Chemokines play a vital role in tumor progression and metastasis. Chemokines are involved in the growth of many cancers including breast cancer, ovarian cancer, pancreatic cancer, melanoma, lung cancer, gastric cancer, acute lymphoblastic leukemia, colon cancer, non-small lung cancer and non-hodgkin's lymphoma among many others. The expression of chemokines and their receptors is altered in many malignancies and leads to aberrant chemokine receptor signaling. This review focuses on the role of chemokines in key processes that facilitate tumor progression including proliferation, senescence, angiogenesis, epithelial mesenchymal transition, immune evasion and metastasis. PMID:24259307

75 FR 11527 - KC Hydro LLC; Notice of Competing Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-11

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13617-000] KC Hydro LLC..., 2010. On November 6, 2009, KC Hydro LLC filed an application for a preliminary permit, pursuant to... Sackheim, KC Hydro LLC, 5096 Cocoa Palm Way, Fair Oaks, CA 95628, phone: (916) 962-2271, e-mail: oregon...

Air Force KC-X Tanker Aircraft Program: Background and Issues for Congress

DTIC Science & Technology

2009-12-22

24, 2009, the Department of Defense (DOD) announced its proposed strategy for conducting a new competition between Boeing and a team consisting of...acquire a new tanker over the past several years have ultimately failed. DOD’s proposed new KC-X acquisition competition strategy poses several...5 DOD’s Proposed New KC-X Competition Strategy ...............................................................5

Indigo naturalis upregulates claudin-1 expression in human keratinocytes and psoriatic lesions.

PubMed

Lin, Yin-Ku; Chen, Hsiao-Wen; Leu, Yann-Lii; Yang, Yueh-Lung; Fang, Yu; Su Pang, Jong-Hwei; Hwang, Tsong-Long

2013-01-30

Indigo naturalis is used in traditional Chinese medicine to treat various dermatoses. Our previous clinical studies showed that indigo naturalis is an effective treatment for psoriasis. Herein, the capabilities of indigo naturalis extract and its derivatives to increase claudin-1 expression and tight junction (TJ) function in human keratinocytes and psoriatic lesions were further studied. Claudin-1 expression in psoriatic plaques with or without indigo naturalis treatment was analyzed by immunohistochemical methods. In primary human keratinocytes, the expression of claudin-1 was analyzed by fluorescent immunostaining, a real-time RT-PCR, and Western blot analysis. The effect of indigo naturalis on TJs was evaluated by measuring the transepithelial electrical resistance (TEER) and paracellular tracer flux. The indigo naturalis extract upregulated mRNA and protein expressions of claudin-1 and function of TJs in primary human keratinocytes in concentration-dependent manners. Its main components, indirubin, indigo, and tryptanthrin, exerted synergistic effects on upregulating TJ functions in primary human keratinocytes. In addition, indigo naturalis increased the activity of protein kinase C (PKC), and a known potent PKC inhibitor, Ro318220, attenuated the indigo naturalis-induced claudin-1 expression. Significantly, restoration of claudin-1 was observed in healed psoriatic lesions after indigo naturalis treatment. Indigo naturalis upregulates claudin-1 expression and restores TJ function in keratinocytes. Our data also suggest that indirubin, indigo, and tryptanthrin have a synergistic effect on TJ function. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

A Model to Predict the Risk of Keratinocyte Carcinomas.

PubMed

Whiteman, David C; Thompson, Bridie S; Thrift, Aaron P; Hughes, Maria-Celia; Muranushi, Chiho; Neale, Rachel E; Green, Adele C; Olsen, Catherine M

2016-06-01

Basal cell and squamous cell carcinomas of the skin are the commonest cancers in humans, yet no validated tools exist to estimate future risks of developing keratinocyte carcinomas. To develop a prediction tool, we used baseline data from a prospective cohort study (n = 38,726) in Queensland, Australia, and used data linkage to capture all surgically excised keratinocyte carcinomas arising within the cohort. Predictive factors were identified through stepwise logistic regression models. In secondary analyses, we derived separate models within strata of prior skin cancer history, age, and sex. The primary model included terms for 10 items. Factors with the strongest effects were >20 prior skin cancers excised (odds ratio 8.57, 95% confidence interval [95% CI] 6.73-10.91), >50 skin lesions destroyed (odds ratio 3.37, 95% CI 2.85-3.99), age ≥ 70 years (odds ratio 3.47, 95% CI 2.53-4.77), and fair skin color (odds ratio 1.75, 95% CI 1.42-2.15). Discrimination in the validation dataset was high (area under the receiver operator characteristic curve 0.80, 95% CI 0.79-0.81) and the model appeared well calibrated. Among those reporting no prior history of skin cancer, a similar model with 10 factors predicted keratinocyte carcinoma events with reasonable discrimination (area under the receiver operator characteristic curve 0.72, 95% CI 0.70-0.75). Algorithms using self-reported patient data have high accuracy for predicting risks of keratinocyte carcinomas. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Chemokine scavenger D6 is expressed by trophoblasts and aids the survival of mouse embryos transferred into allogeneic recipients.

PubMed

Madigan, Judith; Freeman, Dilys J; Menzies, Fiona; Forrow, Steve; Nelson, Scott M; Young, Anne; Sharkey, Andrew; Moffett, Ashley; Graham, Gerard J; Greer, Ian A; Rot, Antal; Nibbs, Robert J B

2010-03-15

Proinflammatory CC chemokines are thought to drive recruitment of maternal leukocytes into gestational tissues and regulate extravillous trophoblast migration. The atypical chemokine receptor D6 binds many of these chemokines and is highly expressed by the human placenta. D6 is thought to act as a chemokine scavenger because, when ectopically expressed in cell lines in vitro, it efficiently internalizes proinflammatory CC chemokines and targets them for destruction in the absence of detectable chemokine-induced signaling. Moreover, D6 suppresses inflammation in many mouse tissues, and notably, D6-deficient fetuses in D6-deficient female mice show increased susceptibility to inflammation-driven resorption. In this paper, we report strong anti-D6 immunoreactivity, with specific intracellular distribution patterns, in trophoblast-derived cells in human placenta, decidua, and gestational membranes throughout pregnancy and in trophoblast disease states of hydatidiform mole and choriocarcinoma. We show, for the first time, that endogenous D6 in a human choriocarcinoma-derived cell line can mediate progressive chemokine scavenging and that the D6 ligand CCL2 can specifically associate with human syncytiotrophoblasts in term placenta in situ. Moreover, despite strong chemokine production by gestational tissues, levels of D6-binding chemokines in maternal plasma decrease during pregnancy, even in women with pre-eclampsia, a disease associated with increased maternal inflammation. In mice, D6 is not required for syngeneic or semiallogeneic fetal survival in unchallenged mice, but interestingly, it does suppress fetal resorption after embryo transfer into fully allogeneic recipients. These data support the view that trophoblast D6 scavenges maternal chemokines at the fetomaternal interface and that, in some circumstances, this can help to ensure fetal survival.

Investigation of surface tension phenomena using the KC-135 aircraft

NASA Technical Reports Server (NTRS)

Alter, W. S.

1982-01-01

The microgravity environment of the KC-135 aircraft was utilized in three experiments designed to determine the following: (1) the feasibility of measuring critical wetting temperatures; (2) the effectiveness of surface tension as a means of keeping the cushioning heat transfer liquid in the furnace during ampoule translation; and (3) whether a non-wetting fluid would separate from the ampoule wall under low gravity conditions. This trio of investigations concerning surface phenomena demonstrates the effectiveness of the KC-135 as a microgravity research environment for small-scale, hand-held experiments.

Profiling Heparin-Chemokine Interactions Using Synthetic Tools

PubMed Central

de Paz, Jose L.; Moseman, E. Ashley; Noti, Christian; Polito, Laura; von Andrian, Ulrich H.; Seeberger, Peter H.

2009-01-01

Glycosaminoglycans (GAGs), such as heparin or heparan sulfate, are required for the in vivo function of chemokines. Chemokines play a crucial role in the recruitment of leukocyte subsets to sites of inflammation and lymphocytes trafficking. GAG-chemokine interactions mediate cell migration and determine which leukocyte subsets enter tissues. Identifying the exact GAC sequences that bind to particular chemokines is key to understand chemokine function at the molecular level and develop strategies to interfere with chemokine-mediated processes. Here, we characterize the heparin binding profiles of eight chemokines (CCL21, IL-8, CXCL12, CXCL13, CCL19, CCL25, CCL28, and CXCL16) by employing heparin microarrays containing a small library of synthetic heparin oligosaccharides. The chemokines differ significantly in their interactions with heparin oligosaccharides: While some chemokines, (e.g., CCL21) strongly bind to a hexasaccharide containing the GlcNSO3(6-OSO3)-IdoA(2-OSO3) repeating unit, CCL19 does not bind and CXCL12 binds only weakly. The carbohydrate microarray binding results were validated by surface plasmon resonance experiments. In vitro chemotaxis assays revealed that dendrimers coated with the fully sulfated heparin hexasaccharide inhibit lymphocyte migration toward CCL21. Migration toward CXCL12 or CCL19 was not affected. These in vitro homing assays indicate that multivalent synthetic heparin dendrimers inhibit the migration of lymphocytes toward certain chemokine gradients by blocking the formation of a chemokine concentration gradient on GAG endothelial chains. These findings are in agreement with preliminary in vivo measurements of circulating lymphocytes. The results presented here contribute to the understanding of GAG-chemokine interactions, a first step toward the design of novel drugs that modulate chemokine activity. PMID:18030990

KC-135 Winglet Program Review

NASA Technical Reports Server (NTRS)

1982-01-01

The results of a joint NASA/USAF program to develop flight test winglets on a KC-135 aircraft are reviewed. The winglet development from concept through wind tunnel and flight tests is discussed. Predicted, wind tunnel, and flight test results are compared for the performance, loads and flutter characteristics of the winglets. The flight test winglets had a variable winglet cant and incidence angle capability which enabled a limited evaluation of the effects of these geometry changes.

Air Force KC-X Tanker Aircraft Program: Background and Issues for Congress

DTIC Science & Technology

2009-12-07

24, 2009, the Department of Defense (DOD) announced its proposed strategy for conducting a new competition between Boeing and a team consisting of...acquire a new tanker over the last several years have ultimately failed. DOD’s proposed new KC-X acquisition competition strategy poses several...5 DOD’s Proposed New KC-X Competition Strategy ...............................................................5 Response to the Draft RFP

Cell lineage mapping of taste bud cells and keratinocytes in the mouse tongue and soft palate.

PubMed

Okubo, Tadashi; Clark, Cheryl; Hogan, Brigid L M

2009-02-01

The epithelium of the mouse tongue and soft palate consists of at least three distinct epithelial cell populations: basal cells, keratinized cells organized into filiform and fungiform papillae, and taste receptor cells present in tight clusters known as taste buds in the fungiform and circumvallate papillae and soft palate. All three cell types develop from the simple epithelium of the embryonic tongue and palate, and are continually replaced in the adult by cell turnover. Previous studies using pulse-chase tritiated thymidine labeling in the adult mouse provided evidence for a high rate of cell turnover in the keratinocytes (5-7 days) and taste buds (10 days). However, little is known about the localization and phenotype of the long-term stem or progenitor cells that give rise to the mature taste bud cells and surrounding keratinocytes in these gustatory tissues. Here, we make use of a tamoxifen-inducible K14-CreER transgene and the ROSA26 LacZ reporter allele to lineage trace the mature keratinocytes and taste bud cells of the early postnatal and adult mouse tongue and soft palate. Our results support the hypothesis that both the pore keratinocytes and receptor cells of the taste bud are derived from a common K14(+)K5(+)Trp63(+)Sox2(+) population of bipotential progenitor cells located outside the taste bud. The results are also compatible with models in which the keratinocytes of the filiform and fungiform papillae are derived from basal progenitor cells localized at the base of these structures.

Effect of isosecotanapartholide isolated from Artemisia princeps Pampanini on IL‑33 production and STAT‑1 activation in HaCaT keratinocytes.

PubMed

Oh, Chang Taek; Jang, Yu-Jin; Kwon, Tae-Rin; Im, Songi; Kim, Soon Re; Seok, Joon; Kim, Gun-Yong; Kim, Young-Heui; Mun, Seog Kyun; Kim, Beom Joon

2017-05-01

The present study aimed to investigate the anti‑inflammatory effect and mechanism of action of isosecotanapartholide (ISTP), isolated from Artemisia princeps Pampanini extract (APE). The effects of ISTP and APE on the proliferation of human keratinocytes following stimulation by tumor necrosis factor‑α/interferon‑γ were assessed. ISTP and APE downregulated the expression levels of signal transducer and activator of transcription‑1 (STAT‑1), and reduced interleukin‑33 (IL‑33) production. ISTP and APE inhibited the mRNA expression levels of thymus and activation‑regulated chemokine (TARC/CCL17) in a dose‑dependent manner. Western blot analysis demonstrated that ISTP and APE dose‑dependently inhibited protein expression levels of intercellular adhesion molecule‑1 and phosphorylation of STAT‑1. The results of the present study indicate that ISTP may inhibit TARC/CCL17 production in human epidermal keratinocytes via the STAT‑1 signaling pathway and may be associated with the inhibition of IL‑33 production. The current study indicated that ISTP is an active component in APE and may be a potential therapeutic agent for the treatment of inflammatory skin disorders.

Noninvasive electromagnetic fields on keratinocyte growth and migration.

PubMed

Huo, Ran; Ma, Qianli; Wu, James J; Chin-Nuke, Kayla; Jing, Yuqi; Chen, Juan; Miyar, Maria E; Davis, Stephen C; Li, Jie

2010-08-01

Although evidence has shown that very small electrical currents produce a beneficial therapeutic result for wounds, noninvasive electromagnetic field (EMF) therapy has consisted mostly of anecdotal clinical reports, with very few well-controlled laboratory mechanistic studies. In this study, we evaluate the effects and potential mechanisms of a noninvasive EMF device on skin wound repair. The effects of noninvasive EMF on keratinocytes and fibroblasts were assessed via proliferation and incisional wound model migration assays. cDNA microarray and RT-PCR were utilized to assess genetic expression changes in keratinocytes after noninvasive EMF treatment. In vitro analyses with human skin keratinocyte cultures demonstrated that noninvasive EMFs have a strong effect on accelerating keratinocyte migration and a relatively weaker effect on promoting keratinocyte proliferation. The positive effects of noninvasive EMFs on cell migration and proliferation seem keratinocyte-specific without such effects seen on dermal fibroblasts. cDNA microarray and RT-PCR performed revealed increased expression of CRK7 and HOXC8 genes in treated keratinocytes. This study suggests that a noninvasive EMF accelerates wound re-epithelialization through a mechanism of promoting keratinocyte migration and proliferation, possibly due to upregulation of CRK7 and HOXC8 genes. Copyright 2010 Elsevier Inc. All rights reserved.

Chemokines in teleost fish species.

PubMed

Alejo, Alí; Tafalla, Carolina

2011-12-01

Chemokines are chemoattractant cytokines defined by the presence of four conserved cysteine residues which in mammals can be divided into four subfamilies depending on the arrangement of the first two conserved cysteines in their sequence: CXC (α), CC (β), C and CX(3)C classes. Evolutionarily, fish can be considered as an intermediate step between species which possess only innate immunity (invertebrates) and species with a fully developed acquired immune network such as mammals. Therefore, the functionality of their different immune cell types and molecules is sometimes also intermediate between innate and acquired responses. The first chemokine gene identified in a teleost was a rainbow trout (Oncorhynchus mykiss) chemokine designated as CK1 in 1998. Since then, many different chemokine genes have been identified in several fish species, but their role in homeostasis and immune response remains largely unknown. Extensive genomic duplication events and the fact that chemokines evolve more quickly than other immune genes, make it very difficult to establish true orthologues between fish and mammalian chemokines that would help us with the ascription of immune roles. In this review, we describe the current state of knowledge of chemokine biology in teleost fish, focusing mainly on which genes have been identified so far and highlighting the most important aspects of their expression regulation, due to the great lack of functional information available for them. As the number of chemokine genes begins to close down for some teleost species, there is an important need for functional assays that may elucidate the role of each of these molecules within the fish immune response. Copyright © 2011 Elsevier Ltd. All rights reserved.

Keratinocytes in culture accumulate phagocytosed melanosomes in the perinuclear area.

PubMed

Ando, Hideya; Niki, Yoko; Yoshida, Masaki; Ito, Masaaki; Akiyama, Kaoru; Kim, Jin-Hwa; Yoon, Tae-Jin; Lee, Jeung-Hoon; Matsui, Mary S; Ichihashi, Masamitsu

2010-02-01

There are many techniques for evaluating melanosome transfer to keratinocytes but the spectrophotometric quantification of melanosomes incorporated by keratinocyte phagocytosis has not been previously reported. Here we describe a new method that allows the spectrophotometric visualization of melanosome uptake by normal human keratinocytes in culture. Fontana-Masson staining of keratinocytes incubated with isolated melanosomes showed the accumulation of incorporated melanosomes in the perinuclear areas of keratinocytes within 48 h. Electron microscopic observations of melanosomes ingested by keratinocytes revealed that many phagosomes containing clusters of melanosomes or their fragments were localized in the perinuclear area. A known inhibitor of keratinocyte phagocytosis which inhibits protease-activated receptor-2, i.e., soybean trypsin inhibitor, decreased melanosome uptake by keratinocytes in a dose-dependent manner. These data suggest that our method is a useful model to quantitate keratinocyte phagocytosis of melanosomes visually in vitro.

Citrullinated Chemokines in Rheumatoid Arthritis

DTIC Science & Technology

2016-12-01

immunosorbent assay ( ELISA ) in RA and normal (NL) sera and in RA, osteoarthritis (OA), and other inflammatory rheumatic disease (OD) synovial fluids (SFs... ELISA ) Epithelial Neutrophil Chemoattractant Peptide-78 (ENA-78/CXCL5) Monocyte Chemoattractant Protein-1 (MCP-1/CCL2) Macrophage Inflammatory...Citrullinated chemokines are highly expressed in RA sera and SFs. Citrullinated chemokines were measured using an ELISA in which chemokines were captured on

CXC chemokine ligand 4 (Cxcl4) is a platelet-derived mediator of experimental liver fibrosis.

PubMed

Zaldivar, Mirko Moreno; Pauels, Katrin; von Hundelshausen, Philipp; Berres, Marie-Luise; Schmitz, Petra; Bornemann, Jörg; Kowalska, M Anna; Gassler, Nikolaus; Streetz, Konrad L; Weiskirchen, Ralf; Trautwein, Christian; Weber, Christian; Wasmuth, Hermann E

2010-04-01

Liver fibrosis is a major cause of morbidity and mortality worldwide. Platelets are involved in liver damage, but the underlying molecular mechanisms remain elusive. Here, we investigate the platelet-derived chemokine (C-X-C motif) ligand 4 (CXCL4) as a molecular mediator of fibrotic liver damage. Serum concentrations and intrahepatic messenger RNA of CXCL4 were measured in patients with chronic liver diseases and mice after toxic liver injury. Platelet aggregation in early fibrosis was determined by electron microscopy in patients and by immunohistochemistry in mice. Cxcl4(-/-) and wild-type mice were subjected to two models of chronic liver injury (CCl(4) and thioacetamide). The fibrotic phenotype was analyzed by histological, biochemical, and molecular analyses. Intrahepatic infiltration of immune cells was investigated by fluorescence-activated cell sorting, and stellate cells were stimulated with recombinant Cxcl4 in vitro. The results showed that patients with advanced hepatitis C virus-induced fibrosis or nonalcoholic steatohepatitis had increased serum levels and intrahepatic CXCL4 messenger RNA concentrations. Platelets were found directly adjacent to collagen fibrils. The CCl(4) and thioacetamide treatment led to an increase of hepatic Cxcl4 levels, platelet activation, and aggregation in early fibrosis in mice. Accordingly, genetic deletion of Cxcl4 in mice significantly reduced histological and biochemical liver damage in vivo, which was accompanied by changes in the expression of fibrosis-related genes (Timp-1 [tissue inhibitor of matrix metalloproteinase 1], Mmp9 [matrix metalloproteinase 9], Tgf-beta [transforming growth factor beta], IL10 [interleukin 10]). Functionally, Cxcl4(-/-) mice showed a strongly decreased infiltration of neutrophils (Ly6G) and CD8(+) T cells into the liver. In vitro, recombinant murine Cxcl4 stimulated the proliferation, chemotaxis, and chemokine expression of hepatic stellate cells. The results underscore an important role

Thrombospondin-induced adhesion of human keratinocytes.

PubMed Central

Varani, J; Nickoloff, B J; Riser, B L; Mitra, R S; O'Rourke, K; Dixit, V M

1988-01-01

Human epidermal keratinocytes obtained from normal skin attached and spread on thrombospondin (TSP)-coated plastic dishes but failed to attach and spread on untreated plastic culture dishes or dishes coated with fibronectin or laminin. These cells produced minimal amounts of immunoreactive TSP. Keratinocytes established in culture on MCDB 153 medium and maintained for one to three passages in an undifferentiated state by continued cultivation in this low Ca2+-containing medium attached and spread on plastic dishes as well as on TSP-coated dishes. These cells also secreted significant amounts of TSP into the culture medium. When the keratinocytes were incubated for one day in MCDB 153 medium supplemented with high Ca2+ or in MEM (which also contains high Ca2+), there was decreased secretion of TSP into the culture medium concomitant with a reduction in attachment and spreading on plastic culture dishes. Proteolytic fragments of TSP were examined for stimulation of keratinocyte attachment and spreading. A 140-kd fragment produced by removal of the 25-kd heparin-binding domain had similar activity to the intact molecule while the 25-kd fragment was without effect. Further proteolytic treatment of the 140-kd fragment gave rise to a fragment consisting of 120 kd and 18-D moieties held together in disulphide linkage. This fragment did not support attachment or spreading. This study reveals that normal epidermal keratinocytes grown under conditions that maintain the undifferentiated state are able to produce TSP and utilize it as an attachment factor. When keratinocytes are grown under conditions that promote differentiation, ability to produce and utilize TSP is diminished. Since TSP is present at the dermal-epidermal junction and because TSP promotes keratinocyte attachment and spreading, this molecule may play an important role in maintaining normal growth of the basal cell layer and may also participate in reepithelialization during wound repair. Images PMID:2452837

Lysine-specific demethylase 2A (KDM2A) normalizes human embryonic stem cell derived keratinocytes

PubMed Central

Iuchi, Shiro; Green, Howard

2012-01-01

Studies on human lysine-specific demethylase 2A (KDM2A) by others have recently begun. To date, the demethylase activity has been known to reduce expression of genes and eventually inhibit proliferation of cells. However, while attempting to improve proliferation of hES-cell–derived Nod keratinocytes, which grow poorly and have a short life span, we found that high expression of the KDM2A gene improves the poor proliferation of the cells. Of the four isomer cDNAs that we prepared from alternatively spliced KDM2A transcripts, only one stimulates the proliferation. This (KDM2A-N782) encodes the 782AA protein containing the JmjC, CXXC, and Ring domains, but not the F-box and AMN1 domains, unlike KDM2A, which has been studied by other groups. Our results not only show that differently spliced transcripts from a gene result in totally opposite outcomes, but also present critical evidence of the complicated activities of KDM2A, which contains all of the five domains. PMID:22635273

Melanosome uptake is associated with the proliferation and differentiation of keratinocytes.

PubMed

Choi, Hye-In; Sohn, Kyung-Cheol; Hong, Dong-Kyun; Lee, Young; Kim, Chang Deok; Yoon, Tae-Jin; Park, Jin Woon; Jung, Sunggyun; Lee, Jeung-Hoon; Lee, Young Ho

2014-01-01

Melanosomes are synthesized in melanocytes and transferred to neighboring keratinocytes. However, the associations of melanosome uptake with the proliferation and differentiation of keratinocytes are not fully understood. We examined the associations of melanosome uptake with keratinocyte differentiation and proliferation. SV40T-transformed human epidermal keratinocytes (SV-HEKs) were treated with isolated melanosomes. The effects of melanosome uptake on the proliferation and differentiation of the keratinocytes were analyzed by Western blotting and flow cytometry. The relationship between melanosome uptake and keratinocyte differentiation status was verified by determining the melanin content in the cells. Melanosomes reduced the proliferation of SV-HEKs in a dose-dependent manner, but did not induce differentiation. Melanosome uptake was higher in differentiating keratinocytes compared to non-differentiating keratinocytes, and inhibited significantly by PAR-2 inhibitor. Melanosomes inhibit keratinocyte proliferation. Moreover, melanosome uptake is influenced by keratinocyte differentiation status, being highest in mid-stage differentiating keratinocytes in a PAR-2 dependent manner.

Isolation and analysis of a multifunctional triterpene synthase KcMS promoter region from mangrove plant kandelia candel

NASA Astrophysics Data System (ADS)

Basyuni, M.; Wati, R.; Sulistiyono, N.; Sumardi; Oku, H.; Baba, S.; Sagami, H.

2018-03-01

Molecular cloning of Kandelia candel KcMS gene has previously been cloned and encoded a multifunctional triterpene synthase. In this study, the KcMS gene promoter was cloned through Genome walking, sequenced, and analyzed. A 1,358 bp genomic DNA fragment of KcMS promoter was obtained. PLACE and PlantCARE analysis of the KcMS promoter revealed that there was some regulatory elements in response to environmental signals and involved in the regulation of gene expression. Results showed that four kinds of elements are regulated by hormone binding, namely 2 MeJA-responsiveness elements (CGTCA-motif and TGACG-motif), the ABRE (TACGTG) involved in abscisic acid responsiveness, gibberellin-related GARE-motif (AAACAGA), and the TGA-element (AACGAC) as an auxin-responsive element. Several elements in the KcMS have been shown in other plants to be responsive to abiotic stress. These motifs were MBS (CAACTG), TC-rich repeats, and eight light responsive elements. The KcMS promoter was also involved in the activation of defense genes in plants such as HSE (AAAAAATTC) and four circadian control elements (CAANNNNATC). The presence of multipotential regulatory motifs suggested that KcMS may be involved in regulation of plant tolerance to several types of stresses.

Identification of Rice Koji Extract Components that Increase β-Glucocerebrosidase Levels in Human Epidermal Keratinocytes.

PubMed

Maeda, Kazuhisa; Ogino, Yuuka; Nakamura, Ayano; Nakata, Keiji; Kitagawa, Manabu; Ito, Seiki

2018-06-18

Rice miso contains many ingredients derived from rice koji and has been a valuable source of nutrition since ancient times. We found that the consumption of rice miso led to improvements in the moisture content of cheek stratum corneum, skin viscoelasticity, and skin texture. Further, rice miso extract was found to increase the mRNA expression and activity of β-glucocerebrosidase (β-GCase), an enzyme involved in ceramide synthesis in the stratum corneum, in cultures. In this study, we identified the lipid-derived components of rice koji that increase the β-GCase activity in cultured human epidermal keratinocytes. The methanol fraction of rice koji extract induced an increase in the mRNA expression and activity of β-GCase in keratinocytes. The active fraction of rice koji was found to contain phosphatidic acid (PA) and lysophosphatidic acid (LPA). The total PA concentration in rice koji was 973.9 ng/mg dry weight, which was 17.5 times higher than that in steamed rice. Among the molecular species, PA_18:2/18:2 was the most frequently found. The total LPA concentration in rice koji was 29.6 ng/mg dry weight, and 2-LPA_18:2 was the most frequently found LPA. Since PA and LPA increase the mRNA expression and activity of β-GCase in keratinocytes, they are thought to be the active ingredients in rice koji that increase the β-GCase levels in human epidermal keratinocytes.

Post-mitotic human dermal fibroblasts efficiently support the growth of human follicular keratinocytes.

PubMed

Limat, A; Hunziker, T; Boillat, C; Bayreuther, K; Noser, F

1989-05-01

For growth at low seeding densities, keratinocytes isolated from human tissues like epidermis or hair follicles are dependent on mesenchyme-derived feeder cells such as the 3T3-cell employed so far. As an alternative method, the present study describes the use of post-mitotic human dermal fibroblasts sublethally irradiated or mitomycin C-treated. Special emphasis was put on efficient growth of primary keratinocyte cultures plated at very low seeding densities. Thus, outer root sheath cells isolated from two anagen human hair follicles and plated in a 35-mm culture dish (3 - 6 X 10(2) attached cells) grew to confluence within 3 weeks (6 - 8 X 10(5) cells). Similar results were obtained for interfollicular keratinocytes. A crucial point for the function of these fibroblast feeder cells is plating at appropriate densities, considering their tremendous increase in cell size at the post-mitotic state. Plating densities of 4 - 5 X 10(3/cm2 allow full spreading of the feeder cells and do not impede the settling and expansion of the keratinocytes. Major advantages of this system include easier handling and better reproducibility than using 3T3-cells. Moreover, homologous fibroblast feeders mimic more closely the physiologic situation and therefore might provide a valuable tool for studying interactions between human mesenchymal and epithelial cells. Finally, potential hazards of using transformed feeder cells from a different species in keratinocyte cultures raised for wound covering in humans could be thus avoided.

T cell costimulation by chemokine receptors.

PubMed

Molon, Barbara; Gri, Giorgia; Bettella, Monica; Gómez-Moutón, Concepción; Lanzavecchia, Antonio; Martínez-A, Carlos; Mañes, Santos; Viola, Antonella

2005-05-01

Signals mediated by chemokine receptors may compete with T cell receptor stop signals and determine the duration of T cell-antigen-presenting cell interactions. Here we show that during T cell stimulation by antigen-presenting cells, T cell chemokine receptors coupled to G(q) and/or G(11) protein were recruited to the immunological synapse by a G(i)-independent mechanism. When chemokine receptors were sequestered at the immunological synapse, T cells became insensitive to chemotactic gradients, formed more stable conjugates and finally responded with enhanced proliferation and cytokine production. We suggest that chemokine receptor trapping at the immunological synapse enhances T cell activation by improving T cell-antigen-presenting cell attraction and impeding the 'distraction' of successfully engaged T cells by other chemokine sources.

Chemokine guided angiogenesis directs coronary vasculature formation in zebrafish

PubMed Central

Harrison, Michael R.M.; Bussmann, Jeroen; Huang, Ying; Zhao, Long; Osorio, Arthela; Burns, C. Geoffrey; Burns, Caroline E.; Sucov, Henry M.; Siekmann, Arndt F.; Lien, Ching-Ling

2015-01-01

SUMMARY Interruption of coronary blood supply severely impairs heart function with often-fatal consequences for heart disease patients. However the formation and maturation of these coronary vessels is not fully understood. Here we provide a detailed analysis of coronary vessel development in zebrafish. We observe that coronary vessels form in zebrafish by angiogenic sprouting of arterial cells derived from the endocardium at the atrioventricular canal. Endothelial cells express the CXC-motif chemokine receptor Cxcr4a and migrate to vascularize the ventricle under the guidance of the myocardium-expressed ligand Cxcl12b. cxcr4a mutant zebrafish fail to form a vascular network, whereas ectopic expression of Cxcl12b ligand induces coronary vessel formation. Importantly, cxcr4a mutant zebrafish fail to undergo heart regeneration following injury. Our results suggest that chemokine-signaling has an essential role in coronary vessel formation by directing migration of endocardium-derived endothelial cells. Poorly developed vasculature in cxcr4a mutants likely underlies decreased regenerative potential in adults. PMID:26017769

Human beta defensin-4 and keratinocyte growth factor gene expression in cultured keratinocyte and fibroblasts of burned patients.

PubMed

Noronha, Silvana Aparecida Alves Corrêa de; Noronha, Samuel Marcos Ribeiro de; Lanziani, Larissa Elias; Ipolito, Michele Zampieri; Ferreira, Lydia Masako; Gragnani, Alfredo

2014-01-01

To evaluate KGF and human beta defensin-4 (HBD-4) levels produced by dermic fibroblasts and keratinocytes cultivated from burned patients' skin samples. Keratinocytes and fibroblasts of 10 patients (four major burns, four minor burns and two controls) were primarily cultivated according to standard methods. HBD-4 and KGF genes were analyzed by quantitative PCR. In fibroblasts, KGF gene expression was 220±80 and 33.33±6.67 (M±SD; N=4), respectively for major and minor burn groups. In keratinocytes, KGF gene expression was 11.2±1.9 and 3.45±0.37 (M±SD; N=4), respectively for major and minor burn groups. In fibroblasts, HBD-4 gene expression was 15.0±4.0 and 11.5±0.5 (M±SD; N=4), respectively for major and minor burn. In keratinocyte, HBD-4 gene expression was 0.0±0.0 and 13.4±4.8 (M±SD; N=4), respectively for major and minor burn. KGF expression was increased in burn patient fibroblasts compared to control group. In keratinocytes culture, KGF suppression is inversely proportional to burn extension; it is active and increased in major burn but decreased in minor burn. HBD-4 expression was increased in fibroblasts and decreased in keratinocytes from all burned patients.

Upregulation of cathepsin S in psoriatic keratinocytes.

PubMed

Schönefuss, Alexander; Wendt, Wiebke; Schattling, Benjamin; Schulten, Roxane; Hoffmann, Klaus; Stuecker, Markus; Tigges, Christian; Lübbert, Hermann; Stichel, Christine

2010-08-01

Cathepsin S (CATS) is a cysteine protease, well known for its role in MHC class II-mediated antigen presentation and extracellular matrix degradation. Disturbance of the expression or metabolism of this protease is a concomitant feature of several diseases. Given this importance we studied the localization and regulation of CATS expression in normal and pathological human/mouse skin. In normal human skin CATS-immunostaining is mainly present in the dermis and is localized in macrophages, Langerhans, T- and endothelial cells, but absent in keratinocytes. In all analyzed pathological skin biopsies, i.e. atopic dermatitis, actinic keratosis and psoriasis, CATS staining is strongly increased in the dermis. But only in psoriasis, CATS-immunostaining is also detectable in keratinocytes. We show that cocultivation with T-cells as well as treatment with cytokines can trigger expression and secretion of CATS, which is involved in MHC II processing in keratinocytes. Our data provide first evidence that CATS expression (i) is selectively induced in psoriatic keratinocytes, (ii) is triggered by T-cells and (iii) might be involved in keratinocytic MHC class II expression, the processing of the MHC class II-associated invariant chain and remodeling of the extracellular matrix. This paper expands our knowledge on the important role of keratinocytes in dermatological disease.

Differential chemokine, chemokine receptor and cytokine expression in Epstein-Barr virus-associated lymphoproliferative diseases.

PubMed

Ohshima, Koichi; Karube, Kennosuke; Hamasaki, Makoto; Tutiya, Takeshi; Yamaguchi, Takahiro; Suefuji, Hiroaki; Suzuki, Keiko; Suzumiya, Junji; Ohga, Shouichi; Kikuchi, Masahiro

2003-08-01

T cell immunity plays an important role in the clinicopathology of Epstein-Barr virus (EBV)-associated diseases. Acute EBV-induced infectious mononucleosis (IM) is a common self-limiting disease, however, other EBV-associated diseases, including chronic active EBV infection (CAEBV), NK cell lymphoma (NKL), and Hodgkin's lymphoma (HL), exhibit distinct clinical features. Chemokines are members of a family of small-secreted proteins. The relationships between chemokines and the chemokine receptor (R) are thought to be important for selectivity of local immunity. Some chemokines, chemokine R and cytokines closely associate with the T cell subtypes, Th1 and Th2 T cells and cytotoxic cells. To clarify the role of T cell immunity in EBV-associated diseases, we conducted gene expression profiling, using chemokine, chemokine R and cytokine DNA chips. Compared to EBV negative non-specific lymphadenitis, CAEBV and NKL exhibited diffuse down- and up-regulation, respectively, of these gene profiles. IM had a predominantly Th1-type profile, whereas HL had a mixed Th1/Th2-type profile. Reduction of the Th1-type cytokine interferon gamma (IFN-gamma) in CAEBV was confirmed by Reverse transcriptase-polymerase chain reaction, whereas IFN-gamma expression was markedly enhanced in NKL, and moderately enhanced in IM. Compared to IM, CAEBV showed slight elevation of "regulated upon activation, normal T expressed and secreted" (RANTES), but almost all other genes assayed were down-regulated. NKL exhibited elevated expression of numerous genes, particularly IFN-gamma-inducible-10 (IP-10) and monokine induced by IFN-gamma (MIG). HL showed variable elevated and reduced expression of various genes, with increased expression of IL-13 receptor and MIG. Our study demonstrated the enormous potential of gene expression profiling for clarifying the pathogenesis of EBV-associated diseases.

Vitamin D protects keratinocytes from deleterious effects of ionizing radiation.

PubMed

Langberg, M; Rotem, C; Fenig, E; Koren, R; Ravid, A

2009-01-01

Radiotherapy can induce severe skin responses that may limit the clinically acceptable radiation dose. The responses include erythema, dry and moist desquamation, erosions and dermal-epidermal blister formation. These effects reflect injury to, and reproductive failure of, epidermal cells and may also be due to dysregulation of the tissue remodelling process caused by excessive proteolytic activity. Calcitriol, the hormonally active vitamin D metabolite, protects keratinocytes from programmed cell death induced by various noxious stimuli. To examine whether calcitriol protects proliferating keratinocytes from the damage inflicted by ionizing radiation under conditions similar to those employed during radiotherapy. Autonomously proliferating HaCaT keratinocytes, used as a model for basal layer keratinocytes, were irradiated using a linear accelerator. Cell death was monitored by vital staining, executioner caspase activation, lactic dehydrogenase release and colony formation assay. Induction of matrix metalloproteinase-9 was assessed by gelatinase activity assay and mRNA determination. Levels of specific proteins were determined by immunoblotting. Treatment with calcitriol inhibited both caspase-dependent and -independent programmed cell death occurring within 48 h of irradiation and increased the colony formation capacity of irradiated cells. These effects may be attributable to inhibition of the c-Jun NH(2)-terminal kinase cascade and to upregulation of the truncated antiapoptotic isoform of p63. Treatment with the hormone also attenuated radiation-induced increase in matrix metalloproteinase-9 protein and mRNA levels. The results of this study suggest that active vitamin D derivatives may attenuate cell death and excessive proteolytic activity in the epidermis due to exposure to ionizing radiation in the course of radiotherapy.

Eicosapentaenoic acid and docosahexaenoic acid reduce UVB- and TNF-alpha-induced IL-8 secretion in keratinocytes and UVB-induced IL-8 in fibroblasts.

PubMed

Storey, Amy; McArdle, Frank; Friedmann, Peter S; Jackson, Malcolm J; Rhodes, Lesley E

2005-01-01

Omega-3 polyunsaturated fatty acids (n-3 PUFA) inhibit ultraviolet B (UVB)-induced inflammation and other inflammatory states, in vivo. We examined whether this may be mediated by modulation of interleukin (IL)-8, a chemokine pivotal to skin inflammation induced by UVB, in epidermal and dermal cells. We also explored the ability of n-3 PUFA to protect against tumor necrosis factor (TNF)-alpha induction of IL-8, and assessed relative potencies of the principal dietary n-3 PUFA, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Pre-supplementation, both HaCaT keratinocyte and CCD922SK fibroblast cell lines showed dose-responses for UVB-induced IL-8 release (p<0.001), assessed 48 h post-irradiation. Cells were supplemented with > or =90% purified EPA, DHA, oleic acid (OA) or vehicle control, for 4.5 d. EPA and DHA supplements were bioavailable to keratinocytes and fibroblasts. In keratinocytes, EPA and DHA were shown to reduce basal secretion of IL-8 by 66% and 63%, respectively (p<0.05), and UVB-induced levels by 66% and 65% at 48 h after 100 mJ per cm2, respectively, (p<0.01). A similar pattern occurred in fibroblasts, whereas OA had no influence on IL-8 release in either cell line. In addition, TNF-alpha-induced IL-8 secretion by keratinocytes was reduced by 54% and 42%, respectively, by EPA and DHA (p<0.001). Hence both n-3 PUFA inhibit production of UVB- and TNF-alpha-induced IL-8 in skin cells; this may be important in the photoprotective and other anti-inflammatory effects conferred by these agents.

Structure of CC Chemokine Receptor 5 with a Potent Chemokine Antagonist Reveals Mechanisms of Chemokine Recognition and Molecular Mimicry by HIV

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

Zheng, Yi; Han, Gye Won; Abagyan, Ruben

CCR5 is the primary chemokine receptor utilized by HIV to infect leukocytes, whereas CCR5 ligands inhibit infection by blocking CCR5 engagement with HIV gp120. To guide the design of improved therapeutics, we solved the structure of CCR5 in complex with chemokine antagonist [5P7]CCL5. Several structural features appeared to contribute to the anti-HIV potency of [5P7]CCL5, including the distinct chemokine orientation relative to the receptor, the near-complete occupancy of the receptor binding pocket, the dense network of intermolecular hydrogen bonds, and the similarity of binding determinants with the FDA-approved HIV inhibitor Maraviroc. Molecular modeling indicated that HIV gp120 mimicked the chemokinemore » interaction with CCR5, providing an explanation for the ability of CCR5 to recognize diverse ligands and gp120 variants. Our findings reveal that structural plasticity facilitates receptor-chemokine specificity and enables exploitation by HIV, and provide insight into the design of small molecule and protein inhibitors for HIV and other CCR5-mediated diseases.« less

Melanosome transfer to and translocation in the keratinocyte.

PubMed

Boissy, Raymond E

2003-01-01

Complexion coloration in humans is primarily regulated by the amount and type of melanin synthesized by the epidermal melanocyte. However, additional and equally contributing factors consist of (1) efficient transfer of melanin from the melanocytes to the neighboring keratinocytes and (2) distribution and degradation of the transferred melanosomes by the recipient keratinocytes. Once synthesized in the cell body of the epidermal melanocyte, pigmented melanosomes are translocated down the dendrites and captured at the dendritic tips via various cytoskeletal elements. Molecules recently identified that participate in this process consist of Rab27a, myosin-Va and melanophilin. Eventually, these peripherally localized melanosomes are transferred to keratinocytes by a presently undefined mechanism. The protease-activated receptor-2 (PAR-2) and unidentified surface lectins and glycoproteins facilitate this transfer process. Once incorporated into the keratinocytes, melanosomes are distributed individually or as clusters, aggregated towards the apical pole of the nucleus, and degraded as the keratinocytes undergo terminal differentiation and desquamation. Ultraviolet irradiation (UVR) can modulate the process of melanosome transfer from the melanocytes to the keratinocytes. UVR can upregulate expression of PAR-2 and lectin-binding receptors and increase phagocytic activity of cultured keratinocytes. Therefore, many cellular and molecular events that occur after melanogenesis contribute to skin color.

Rotation is the primary motion of paired human epidermal keratinocytes.

PubMed

Tate, Sota; Imai, Matome; Matsushita, Natsuki; Nishimura, Emi K; Higashiyama, Shigeki; Nanba, Daisuke

2015-09-01

Collective motion of keratinocytes is involved in morphogenesis, homeostasis, and wound healing of the epidermis. Yet how the collective motion of keratinocytes emerges from the behavior of individual cells is still largely unknown. The aim of this study was to find the cellular behavior that links single and collective motion of keratinocytes. We investigated the behavior of two-cell colonies of HaCaT keratinocytes by a combination of time-lapse imaging and image processing. The two-cell colonies of HaCaT cells were formed as a contacted pair of keratinocyte clones. Image analysis and cell culture experiments revealed that the rotational speed of two-cell colonies was positively associated with their proliferative capacity. α6 integrin was required for the rotational motion of two-cell keratinocyte colonies. We also confirmed that two-cell colonies of keratinocytes predominantly exhibited the rotational, but not translational, motion, two modes of motion in a contact pair of rotating objects. The rotational motion is the primary motion of two-cell keratinocyte colonies and its speed is positively associated with their proliferative capacity. This study suggests that the assembly of rotating keratinocytes generates the collective motion of proliferative keratinocytes during morphogenesis and wound healing of the epidermis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

The protease-activated receptor-2 upregulates keratinocyte phagocytosis.

PubMed

Sharlow, E R; Paine, C S; Babiarz, L; Eisinger, M; Shapiro, S; Seiberg, M

2000-09-01

The protease-activated receptor-2 (PAR-2) belongs to the family of seven transmembrane domain receptors, which are activated by the specific enzymatic cleavage of their extracellular amino termini. Synthetic peptides corresponding to the tethered ligand domain (SLIGRL in mouse, SLIGKV in human) can activate PAR-2 without the need for receptor cleavage. PAR-2 activation is involved in cell growth, differentiation and inflammatory processes, and was shown to affect melanin and melanosome ingestion by human keratinocytes. Data presented here suggest that PAR-2 activation may regulate human keratinocyte phagocytosis. PAR-2 activation by trypsin, SLIGRL or SLIGKV increased the ability of keratinocytes to ingest fluorescently labeled microspheres or E. coli K-12 bioparticles. This PAR-2 mediated increase in keratinocyte phagocytic capability correlated with an increase in actin polymerization and *-actinin reorganization, cell surface morphological changes and increased soluble protease activity. Moreover, addition of serine protease inhibitors downmodulated both the constitutive and the PAR-2 mediated increases in phagocytosis, suggesting that serine proteases mediate this functional activity in keratinocytes. PAR-2 involvement in keratinocyte phagocytosis is a novel function for this receptor.

Malondialdehyde-acetaldehyde (MAA) adducted proteins bind to scavenger receptor A in airway epithelial cells.

PubMed

Berger, John P; Simet, Samantha M; DeVasure, Jane M; Boten, Jessica A; Sweeter, Jenea M; Kharbanda, Kusum K; Sisson, Joseph H; Wyatt, Todd A

2014-08-01

Co-exposure to cigarette smoke and ethanol generates malondialdehyde and acetaldehyde, which can subsequently lead to the formation of aldehyde-adducted proteins. We have previously shown that exposure of bronchial epithelial cells to malondialdehyde-acetaldehyde (MAA) adducted protein increases protein kinase C (PKC) activity and proinflammatory cytokine release. A specific ligand to scavenger receptor A (SRA), fucoidan, blocks this effect. We hypothesized that MAA-adducted protein binds to bronchial epithelial cells via SRA. Human bronchial epithelial cells (BEAS-2B) were exposed to MAA-adducted protein (either bovine serum albumin [BSA-MAA] or surfactant protein D [SPD-MAA]) and SRA examined using confocal microscopy, fluorescent activated cell sorting (FACS), and immunoprecipitation. Differentiated mouse tracheal epithelial cells (MTEC) cultured by air-liquid interface were assayed for MAA-stimulated PKC activity and keratinocyte-derived chemokine (KC) release. Specific cell surface membrane dye co-localized with upregulated SRA after exposure to MAA for 3-7 min and subsided by 20 min. Likewise, MAA-adducted protein co-localized to SRA from 3 to 7 min with a subsequent internalization of MAA by 10 min. These results were confirmed using FACS analysis and revealed a reduced mean fluorescence of SRA after 3 min. Furthermore, increased amounts of MAA-adducted protein could be detected by Western blot in immunoprecipitated SRA samples after 3 min treatment with MAA. MAA stimulated PKCε-mediated KC release in wild type, but not SRA knockout mice. These data demonstrate that aldehyde-adducted proteins in the lungs rapidly bind to SRA and internalize this receptor prior to the MAA-adducted protein stimulation of PKC-dependent inflammatory cytokine release in airway epithelium. Copyright © 2014 Elsevier Inc. All rights reserved.

Malondialdehyde-acetaldehyde (MAA) adducted proteins bind to scavenger receptor A in airway epithelial cells

PubMed Central

Berger, John P.; Simet, Samantha M.; DeVasure, Jane M.; Boten, Jessica A.; Sweeter, Jenea M.; Kharbanda, Kusum K.; Sisson, Joseph H.; Wyatt, Todd A.

2014-01-01

Co-exposure to cigarette smoke and ethanol generates malondialdehyde and acetaldehyde, which can subsequently lead to the formation of aldehyde-adducted proteins. We have previously shown that exposure of bronchial epithelial cells to malondialdehyde-acetaldehyde (MAA) adducted protein increases protein kinase C (PKC) activity and proinflammatory cytokine release. A specific ligand to scavenger receptor A (SRA), fucoidan, blocks this effect. We hypothesized that MAA-adducted protein binds to bronchial epithelial cells via SRA. Human bronchial epithelial cells (BEAS-2B) were exposed to MAA-adducted protein (either bovine serum albumin [BSA-MAA] or surfactant protein D [SPD-MAA]) and SRA examined using confocal microscopy, fluorescent activated cell sorting (FACS), and immunoprecipitation. Differentiated mouse tracheal epithelial cells (MTEC) cultured by air-liquid interface were assayed for MAA-stimulated PKC activity and keratinocyte-derived chemokine (KC) release. Specific cell surface membrane dye co-localized with upregulated SRA after exposure to MAA for 3–7 min and subsided by 20 min. Likewise, MAA-adducted protein co-localized to SRA from 3–7 min with a subsequent internalization of MAA by 10 min. These results were confirmed using FACS analysis and revealed a reduced mean fluorescence of SRA after 3 min. Furthermore, increased amounts of MAA-adducted protein could be detected by Western blot in immunoprecipitated SRA samples after 3 min treatment with MAA. MAA stimulated PKCε-mediated KC release in wild type, but not SRA knockout mice. These data demonstrate that aldehyde-adducted proteins in the lungs rapidly bind to SRA and internalize this receptor prior to the MAA-adducted protein stimulation of PKC-dependent inflammatory cytokine release in airway epithelium. PMID:24880893

Targeting galectin-1-induced angiogenesis mitigates the severity of endometriosis.

PubMed

Bastón, Juan I; Barañao, Rosa I; Ricci, Analía G; Bilotas, Mariela A; Olivares, Carla N; Singla, José J; Gonzalez, Alejandro M; Stupirski, Juan C; Croci, Diego O; Rabinovich, Gabriel A; Meresman, Gabriela F

2014-11-01

Endometriosis is characterized by the presence of endometrial tissue outside the uterus that causes severe pelvic pain and infertility in women of reproductive age. Although not completely understood, the pathophysiology of the disease involves chronic dysregulation of inflammatory and vascular signalling. In the quest for novel therapeutic targets, we investigated the involvement of galectin-1 (Gal-1), an endogenous glycan-binding protein endowed with both immunosuppressive and pro-angiogenic activities, in the pathophysiology of endometriotic lesions. Here we show that Gal-1 is selectively expressed in stromal and endothelial cells of human endometriotic lesions. Using an experimental endometriosis model induced in wild-type and Gal-1-deficient (Lgals1(-/-) ) mice, we showed that this lectin orchestrates the formation of vascular networks in endometriotic lesions in vivo, facilitating their ectopic growth independently of vascular endothelial growth factor (VEGF) and the keratinocyte-derived CXC-motif (CXC-KC) chemokine. Targeting Gal-1 using a specific neutralizing mAb reduced the size and vascularized area of endometriotic lesions within the peritoneal compartment. These results underline the essential role of Gal-1 during endometriosis and validate this lectin as a possible target for the treatment of disease. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

An ethanol extract derived from Bonnemaisonia hamifera scavenges ultraviolet B (UVB) radiation-induced reactive oxygen species and attenuates UVB-induced cell damage in human keratinocytes.

PubMed

Piao, Mei Jing; Hyun, Yu Jae; Cho, Suk Ju; Kang, Hee Kyoung; Yoo, Eun Sook; Koh, Young Sang; Lee, Nam Ho; Ko, Mi Hee; Hyun, Jin Won

2012-12-14

The present study investigated the photoprotective properties of an ethanol extract derived from the red alga Bonnemaisonia hamifera against ultraviolet B (UVB)-induced cell damage in human HaCaT keratinocytes. The Bonnemaisonia hamifera ethanol extract (BHE) scavenged the superoxide anion generated by the xanthine/xanthine oxidase system and the hydroxyl radical generated by the Fenton reaction (FeSO₄ + H₂O₂), both of which were detected by using electron spin resonance spectrometry. In addition, BHE exhibited scavenging activity against the 1,1-diphenyl-2-picrylhydrazyl radical and intracellular reactive oxygen species (ROS) that were induced by either hydrogen peroxide or UVB radiation. BHE reduced UVB-induced apoptosis, as shown by decreased apoptotic body formation and DNA fragmentation. BHE also attenuated DNA damage and the elevated levels of 8-isoprostane and protein carbonyls resulting from UVB-mediated oxidative stress. Furthermore, BHE absorbed electromagnetic radiation in the UVB range (280-320 nm). These results suggest that BHE protects human HaCaT keratinocytes against UVB-induced oxidative damage by scavenging ROS and absorbing UVB photons, thereby reducing injury to cellular components.

Differential effect of extracellular matrix derived from papillary and reticular fibroblasts on epidermal development in vitro.

PubMed

Janson, David; Rietveld, Marion; Mahé, Christian; Saintigny, Gaëlle; El Ghalbzouri, Abdoelwaheb

2017-06-01

Papillary and reticular fibroblasts have different effects on keratinocyte proliferation and differentiation. The aim of this study was to investigate whether these effects are caused by differential secretion of soluble factors or by differential generation of extracellular matrix from papillary and reticular fibroblasts. To study the effect of soluble factors, keratinocyte monolayer cultures were grown in papillary or reticular fibroblast-conditioned medium. To study the effect of extracellular matrix, keratinocytes were grown on papillary or reticular-derived matrix. Conditioned medium from papillary or reticular fibroblasts did not differentially affect keratinocyte viability or epidermal development. However, keratinocyte viability was increased when grown on matrix derived from papillary, compared with reticular, fibroblasts. In addition, the longevity of the epidermis was increased when cultured on papillary fibroblast-derived matrix skin equivalents compared with reticular-derived matrix skin equivalents. The findings indicate that the matrix secreted by papillary and reticular fibroblasts is the main causal factor to account for the differences in keratinocyte growth and viability observed in our study. Differences in response to soluble factors between both populations were less significant. Matrix components specific to the papillary dermis may account for the preferential growth of keratinocytes on papillary dermis.

Human Keratinocyte Growth and Differentiation on Acellular Porcine Dermal Matrix in relation to Wound Healing Potential

PubMed Central

Zajicek, Robert; Mandys, Vaclav; Mestak, Ondrej; Sevcik, Jan; Königova, Radana; Matouskova, Eva

2012-01-01

A number of implantable biomaterials derived from animal tissues are now used in modern surgery. Xe-Derma is a dry, sterile, acellular porcine dermis. It has a remarkable healing effect on burns and other wounds. Our hypothesis was that the natural biological structure of Xe-Derma plays an important role in keratinocyte proliferation and formation of epidermal architecture in vitro as well as in vivo. The bioactivity of Xe-Derma was studied by a cell culture assay. We analyzed growth and differentiation of human keratinocytes cultured in vitro on Xe-Derma, and we compared the results with formation of neoepidermis in the deep dermal wounds treated with Xe-Derma. Keratinocytes cultured on Xe-Derma submerged in the culture medium achieved confluence in 7–10 days. After lifting the cultures to the air-liquid interface, the keratinocytes were stratified and differentiated within one week, forming an epidermis with basal, spinous, granular, and stratum corneum layers. Immunohistochemical detection of high-molecular weight cytokeratins (HMW CKs), CD29, p63, and involucrin confirmed the similarity of organization and differentiation of the cultured epidermal cells to the normal epidermis. The results suggest that the firm natural structure of Xe-Derma stimulates proliferation and differentiation of human primary keratinocytes and by this way improves wound healing. PMID:22629190

Human keratinocyte growth and differentiation on acellular porcine dermal matrix in relation to wound healing potential.

PubMed

Zajicek, Robert; Mandys, Vaclav; Mestak, Ondrej; Sevcik, Jan; Königova, Radana; Matouskova, Eva

2012-01-01

A number of implantable biomaterials derived from animal tissues are now used in modern surgery. Xe-Derma is a dry, sterile, acellular porcine dermis. It has a remarkable healing effect on burns and other wounds. Our hypothesis was that the natural biological structure of Xe-Derma plays an important role in keratinocyte proliferation and formation of epidermal architecture in vitro as well as in vivo. The bioactivity of Xe-Derma was studied by a cell culture assay. We analyzed growth and differentiation of human keratinocytes cultured in vitro on Xe-Derma, and we compared the results with formation of neoepidermis in the deep dermal wounds treated with Xe-Derma. Keratinocytes cultured on Xe-Derma submerged in the culture medium achieved confluence in 7-10 days. After lifting the cultures to the air-liquid interface, the keratinocytes were stratified and differentiated within one week, forming an epidermis with basal, spinous, granular, and stratum corneum layers. Immunohistochemical detection of high-molecular weight cytokeratins (HMW CKs), CD29, p63, and involucrin confirmed the similarity of organization and differentiation of the cultured epidermal cells to the normal epidermis. The results suggest that the firm natural structure of Xe-Derma stimulates proliferation and differentiation of human primary keratinocytes and by this way improves wound healing.

A Method for the Immortalization of Newborn Mouse Skin Keratinocytes

PubMed Central

Hammiller, Brianna O.; El-Abaseri, Taghrid Bahig; Dlugosz, Andrzej A.; Hansen, Laura A.

2015-01-01

Isolation and culture of mouse primary epidermal keratinocytes is a common technique that allows for easy genetic and environmental manipulation. However, due to their limited lifespan in culture, experiments utilizing primary keratinocytes require large numbers of animals, and are time consuming and expensive. To avoid these issues, we developed a method for the immortalization of primary mouse epidermal keratinocytes. Upon isolation of newborn epidermal keratinocytes according to established methods, the cells were cultured long-term in keratinocyte growth factor-containing medium. The cells senesced within a few weeks and eventually, small, slowly growing colonies emerged. After they regained confluency, the cells were passaged and slowly refilled the dish. With several rounds of subculture, the cells adapted to culture conditions, were easily subcultured, maintained normal morphology, and were apparently immortal. The immortalized cells retained the ability to differentiate with increased calcium concentrations, and were maintained to high passage numbers while maintaining a relatively stable karyotype. Analysis of multiple immortalized cell lines as well as primary keratinocyte cultures revealed increased numbers of chromosomes, especially in the primary keratinocytes, and chromosomal aberrations in most of the immortalized cultures and in the primary keratinocytes. Orthotopic grafting of immortalized keratinocytes together with fibroblasts onto nude mouse hosts produced skin while v-rasHa infection of the immortalized keratinocytes prior to grafting produced squamous cell carcinoma. In summary, this method of cell line generation allows for decreased use of animals, reduces the expense and time involved in research, and provides a useful model for cutaneous keratinocyte experimentation. PMID:26284198

Flow Cytometry of Human Primary Epidermal and Follicular Keratinocytes

PubMed Central

Gragnani, Alfredo; Ipolito, Michelle Zampieri; Sobral, Christiane S; Brunialti, Milena Karina Coló; Salomão, Reinaldo; Ferreira, Lydia Masako

2008-01-01

Objective: The aim of this study was to characterize using flow cytometry cultured human primary keratinocytes isolated from the epidermis and hair follicles by different methods. Methods: Human keratinocytes derived from discarded fragments of total skin and scalp hair follicles from patients who underwent plastic surgery in the Plastic Surgery Division at UNIFESP were used. The epidermal keratinocytes were isolated by using 3 different methods: the standard method, upon exposure to trypsin for 30 minutes; the second, by treatment with dispase for 18 hours and with trypsin for 10 minutes; and the third, by treatment with dispase for 18 hours and with trypsin for 30 minutes. Follicular keratinocytes were isolated using the standard method. Results: On comparing the group treated with dispase for 18 hours and with trypsin for 10 minutes with the group treated with dispase for 18 hours and with trypsin for 30 minutes, it was observed that the first group presented the largest number of viable cells, the smallest number of cells in late apoptosis and necrosis with statistical significance, and no difference in apoptosis. When we compared the group treated with dispase for 18 hours and with trypsin for 10 minutes with the group treated with trypsin, the first group presented the largest number of viable cells, the smallest number of cells in apoptosis with statistical significance, and no difference in late apoptosis and necrosis. When we compared the results of the group treated with dispase for 18 hours and with trypsin for 10 minutes with the results for follical isolation, there was a statistical difference in apoptosis and viable cells. Conclusion: The isolation method of treatment with dispase for 18 hours and with trypsin for 10 minutes produced the largest number of viable cells and the smallest number of cells in apoptosis/necrosis. PMID:18350110

Flow cytometry of human primary epidermal and follicular keratinocytes.

PubMed

Gragnani, Alfredo; Ipolito, Michelle Zampieri; Sobral, Christiane S; Brunialti, Milena Karina Coló; Salomão, Reinaldo; Ferreira, Lydia Masako

2008-02-19

The aim of this study was to characterize using flow cytometry cultured human primary keratinocytes isolated from the epidermis and hair follicles by different methods. Human keratinocytes derived from discarded fragments of total skin and scalp hair follicles from patients who underwent plastic surgery in the Plastic Surgery Division at UNIFESP were used. The epidermal keratinocytes were isolated by using 3 different methods: the standard method, upon exposure to trypsin for 30 minutes; the second, by treatment with dispase for 18 hours and with trypsin for 10 minutes; and the third, by treatment with dispase for 18 hours and with trypsin for 30 minutes. Follicular keratinocytes were isolated using the standard method. On comparing the group treated with dispase for 18 hours and with trypsin for 10 minutes with the group treated with dispase for 18 hours and with trypsin for 30 minutes, it was observed that the first group presented the largest number of viable cells, the smallest number of cells in late apoptosis and necrosis with statistical significance, and no difference in apoptosis. When we compared the group treated with dispase for 18 hours and with trypsin for 10 minutes with the group treated with trypsin, the first group presented the largest number of viable cells, the smallest number of cells in apoptosis with statistical significance, and no difference in late apoptosis and necrosis. When we compared the results of the group treated with dispase for 18 hours and with trypsin for 10 minutes with the results for follical isolation, there was a statistical difference in apoptosis and viable cells. The isolation method of treatment with dispase for 18 hours and with trypsin for 10 minutes produced the largest number of viable cells and the smallest number of cells in apoptosis/necrosis.

Keratinocytes negatively regulate the N-cadherin levels of melanoma cells via contact-mediated calcium regulation.

PubMed

Chung, Heesung; Jung, Hyejung; Jho, Eek-Hoon; Multhaupt, Hinke A B; Couchman, John R; Oh, Eok-Soo

2018-06-14

In human skin, melanocytes and their neighboring keratinocytes have a close functional interrelationship. Keratinocytes, which represent the prevalent cell type of human skin, regulate melanocytes through various mechanisms. Here, we use a keratinocyte and melanoma co-culture system to show for the first time that keratinocytes regulate the cell surface expression of N-cadherin through cell-cell contact. Compared to mono-cultured human melanoma A375 cells, which expressed high levels of N-cadherin, those co-cultured with the HaCaT human keratinocyte cell line showed reduced levels of N-cadherin. This reduction was most evident in areas of A375 cells that underwent cell-cell contact with the HaCaT cells, whereas HaCaT cell-derived extracellular matrix and conditioned medium both failed to reduce N-cadherin levels. The intracellular level of calcium in co-cultured A375 cells was lower than that in mono-cultured A375 cells, and treatment with a cell-permeant calcium chelator (BAPTA) reduced the N-cadherin level of mono-cultured A375 cells. Furthermore, co-culture with HaCaT cells reduced the expression levels of transient receptor potential cation channel (TRPC) 1, -3 and -6 in A375 cells, and siRNA-mediated multi-depletion of TRPC1, -3 and -6 reduced the N-cadherin level in these cells. Taken together, these data suggest that keratinocytes negatively regulate the N-cadherin levels of melanoma cells via cell-to-cell contact-mediated calcium regulation. Copyright © 2018. Published by Elsevier Inc.

Enhanced Keratinocyte Proliferation and Migration in Co-culture with Fibroblasts

PubMed Central

Wang, Zhenxiang; Wang, Ying; Farhangfar, Farhang; Zimmer, Monica; Zhang, Yongxin

2012-01-01

Wound healing is primarily controlled by the proliferation and migration of keratinocytes and fibroblasts as well as the complex interactions between these two cell types. To investigate the interactions between keratinocytes and fibroblasts and the effects of direct cell-to-cell contact on the proliferation and migration of keratinocytes, keratinocytes and fibroblasts were stained with different fluorescence dyes and co-cultured with or without transwells. During the early stage (first 5 days) of the culture, the keratinocytes in contact with fibroblasts proliferated significantly faster than those not in contact with fibroblasts, but in the late stage (11th to 15th day), keratinocyte growth slowed down in all cultures unless EGF was added. In addition, keratinocyte migration was enhanced in co-cultures with fibroblasts in direct contact, but not in the transwells. Furthermore, the effects of the fibroblasts on keratinocyte migration and growth at early culture stage correlated with heparin-binding EGF-like growth factor (HB-EGF), IL-1α and TGF-β1 levels in the cultures where the cells were grown in direct contact. These effects were inhibited by anti-HB-EGF, anti-IL-1α and anti-TGF-β1 antibodies and anti-HB-EGF showed the greatest inhibition. Co-culture of keratinocytes and IL-1α and TGF-β1 siRNA-transfected fibroblasts exhibited a significant reduction in HB-EGF production and keratinocyte proliferation. These results suggest that contact with fibroblasts stimulates the migration and proliferation of keratinocytes during wound healing, and that HB-EGF plays a central role in this process and can be up-regulated by IL-1α and TGF-β1, which also regulate keratinocyte proliferation differently during the early and late stage. PMID:22911722

CXCL12 Chemokine Expression Suppresses Human Pancreatic Cancer Growth and Metastasis

PubMed Central

Roy, Ishan; Zimmerman, Noah P.; Mackinnon, A. Craig; Tsai, Susan; Evans, Douglas B.; Dwinell, Michael B.

2014-01-01

Pancreatic ductal adenocarcinoma is an unsolved health problem with nearly 75% of patients diagnosed with advanced disease and an overall 5-year survival rate near 5%. Despite the strong link between mortality and malignancy, the mechanisms behind pancreatic cancer dissemination and metastasis are poorly understood. Correlative pathological and cell culture analyses suggest the chemokine receptor CXCR4 plays a biological role in pancreatic cancer progression. In vivo roles for the CXCR4 ligand CXCL12 in pancreatic cancer malignancy were investigated. CXCR4 and CXCR7 were consistently expressed in normal and cancerous pancreatic ductal epithelium, established cell lines, and patient-derived primary cancer cells. Relative to healthy exocrine ducts, CXCL12 expression was pathologically repressed in pancreatic cancer tissue specimens and patient-derived cell lines. To test the functional consequences of CXCL12 silencing, pancreatic cancer cell lines stably expressingthe chemokine were engineered. Consistent with a role for CXCL12 as a tumor suppressor, cells producing the chemokine wereincreasingly adherent and migration deficient in vitro and poorly metastatic in vivo, compared to control cells. Further, CXCL12 reintroduction significantly reduced tumor growth in vitro, with significantly smaller tumors in vivo, leading to a pronounced survival advantage in a preclinical model. Together, these data demonstrate a functional tumor suppressive role for the normal expression of CXCL12 in pancreatic ducts, regulating both tumor growth andcellulardissemination to metastatic sites. PMID:24594697

Platelet chemokines in vascular disease

PubMed Central

Gleissner, Christian A.; von Hundelshausen, Philipp; Ley, Klaus

2009-01-01

Platelets are a rich source of different chemokines and express chemokine receptors. CXCL4 is highly abundant in platelets and involved in promoting monocyte arrest from rolling and monocyte differentiation to macrophages. CXCL4 can also associate with CCL5 and amplify its effect on monocytes. The megakaryocyte CXCL7 gene product is proteolytically cleaved into the strong neutrophil chemoattractant, NAP-2, which has also been implicated in repair cell homing to vascular lesions. Platelet adhesion can induce release of CCL2 and CXCL8 from endothelial cells. Conversely, the chemokines CCL17, CCL22 and CXCL12 made by other cells amplify platelet activation. Platelet chemokines enhance recruitment of various hematopoietic cells to the vascular wall, fostering processes such as neointima formation, atherosclerosis, and thrombosis but also vessel repair and regeneration after vascular injury. PMID:18723831

Mutational analysis of the extracellular disulphide bridges of the atypical chemokine receptor ACKR3/CXCR7 uncovers multiple binding and activation modes for its chemokine and endogenous non-chemokine agonists.

PubMed

Szpakowska, Martyna; Meyrath, Max; Reynders, Nathan; Counson, Manuel; Hanson, Julien; Steyaert, Jan; Chevigné, Andy

2018-07-01

The atypical chemokine receptor ACKR3/CXCR7 plays crucial roles in numerous physiological processes but also in viral infection and cancer. ACKR3 shows strong propensity for activation and, unlike classical chemokine receptors, can respond to chemokines from both the CXC and CC families as well as to the endogenous peptides BAM22 and adrenomedullin. Moreover, despite belonging to the G protein coupled receptor family, its function appears to be mainly dependent on β-arrestin. ACKR3 has also been shown to continuously cycle between the plasma membrane and the endosomal compartments, suggesting a possible role as a scavenging receptor. So far, the molecular basis accounting for these atypical binding and signalling properties remains elusive. Noteworthy, ACKR3 extracellular domains bear three disulphide bridges. Two of them lie on top of the two main binding subpockets and are conserved among chemokine receptors, and one, specific to ACKR3, forms an intra-N terminus four-residue-loop of so far unknown function. Here, by mutational and functional studies, we examined the impact of the different disulphide bridges for ACKR3 folding, ligand binding and activation. We showed that, in contrast to most classical chemokine receptors, none of the extracellular disulphide bridges was essential for ACKR3 function. However, the disruption of the unique ACKR3 N-terminal loop drastically reduced the binding of CC chemokines whereas it only had a mild impact on CXC chemokine binding. Mutagenesis also uncovered that chemokine and endogenous non-chemokine ligands interact and activate ACKR3 according to distinct binding modes characterized by different transmembrane domain subpocket occupancy and N-terminal loop contribution, with BAM22 mimicking the binding mode of CC chemokine N terminus. Copyright © 2018 Elsevier Inc. All rights reserved.

Human eccrine sweat gland cells turn into melanin-uptaking keratinocytes in dermo-epidermal skin substitutes.

PubMed

Böttcher-Haberzeth, Sophie; Biedermann, Thomas; Pontiggia, Luca; Braziulis, Erik; Schiestl, Clemens; Hendriks, Bart; Eichhoff, Ossia M; Widmer, Daniel S; Meuli-Simmen, Claudia; Meuli, Martin; Reichmann, Ernst

2013-02-01

Recently, Biedermann et al. (2010) have demonstrated that human eccrine sweat gland cells can develop a multilayered epidermis. The question still remains whether these cells can fulfill exclusive and very specific functional properties of epidermal keratinocytes, such as the incorporation of melanin, a feature absent in sweat gland cells. We added human melanocytes to eccrine sweat gland cells to let them develop into an epidermal analog in vivo. The interaction between melanocytes and sweat gland-derived keratinocytes was investigated. The following results were gained: (1) macroscopically, a pigmentation of the substitutes was seen 2-3 weeks after transplantation; (2) we confirmed the development of a multilayered, stratified epidermis with melanocytes distributed evenly throughout the basal layer; (3) melanocytic dendrites projected to suprabasal layers; and (4) melanin was observed to be integrated into former eccrine sweat gland cells. These skin substitutes were similar or equal to skin substitutes cultured from human epidermal keratinocytes. The only differences observed were a delay in pigmentation and less melanin uptake. These data suggest that eccrine sweat gland cells can form a functional epidermal melanin unit, thereby providing striking evidence that they can assume one of the most characteristic keratinocyte properties.

Astronaut Catherine G. Coleman aboard KC-135 aircraft

NASA Image and Video Library

1994-05-28

S94-35542 (June 1994) --- Astronaut Catherine G. Coleman, mission specialist, gets a preview of next year?s United States Microgravity Laboratory (USML-2) mission aboard the Space Shuttle Columbia. The weightless experience was afforded by a special parabolic pattern flown by NASA?s KC-135 ?zero gravity? aircraft.

Suppression of Proinflammatory Cytokines in Functionalized Fullerene-Exposed Dermal Keratinocytes

DOE PAGES

Gao, Jun; Wang, Hsing-Lin; Iyer, Rashi

2010-01-01

Initial experiments using differentially functionalized fullerenes, CD-, hexa-, and tris-, suggested a properties dependent effect on cytotoxic and proliferative responses in human skin keratinocytes. In the present study we investigated the cytokine secretion profile of dermal epithelial cells exposed to functionalized fullerenes. Keratinocyte-derived cytokines affect homing and trafficking of normal and malignant epidermal immune as well as nonimmune cells in vivo. These cytokines are critical for regulating activation, proliferation, and differentiation of epidermal cells. Our results indicate that tris- (size range <100 nm) significantly reduces inflammatory cytokine release in a dose- and time-dependent manner. In contrast CD- demonstrated a relatively pro-inflammatorymore » cytokine response, while hexa- did not significantly perturb cytokine responses. Physical and chemical characterizations of these engineered nanomaterials suggest that the disparate biological responses observed may potentially be a function of the aggregation properties of these fullerenes.« less

KC-135 winglet program overview

NASA Technical Reports Server (NTRS)

Barber, M. R.; Selegan, D.

1982-01-01

A joint NASA/USAF program was conducted to accomplish the following objectives: (1) evaluate the benefits that could be achieved from the application of winglets to KC-135 aircraft; and (2) determine the ability of wind tunnel tests and analytical analysis to predict winglet characteristics. The program included wind-tunnel development of a test winglet configuration; analytical predictions of the changes to the aircraft resulting from the application of the test winglet; and finally, flight tests of the developed configuration. Pressure distribution, loads, stability and control, buffet, fuel mileage, and flutter data were obtained to fulfill the objectives of the program.

Induction of senescence pathways in Kindler syndrome primary keratinocytes.

PubMed

Piccinni, E; Di Zenzo, G; Maurelli, R; Dellambra, E; Teson, M; Has, C; Zambruno, G; Castiglia, D

2013-05-01

Individuals with Kindler syndrome (KS) have loss-of-function mutations in the FERMT1 gene that encodes the focal adhesion component kindlin-1. The major clinical manifestation of KS is epidermal atrophy (premature skin ageing). This phenotypic feature is thought to be related to the decreased proliferation rate of KS keratinocytes; nevertheless, molecular mediators of such abnormal behaviour have not been fully elucidated. To investigate how kindlin-1 deficiency affects the proliferative potential of primary human keratinocytes. We serially cultivated nine primary KS keratinocyte strains until senescence and determined their lifespan and colony-forming efficiency (CFE) at each serial passage. The expression of molecular markers of stemness and cellular senescence were investigated by immunoblotting using cell extracts of primary keratinocyte cultures from patients with KS and healthy donors. In another set of experiments, kindlin-1 downregulation in normal keratinocytes was obtained by small interfering RNA (siRNA) technology. We found that KS keratinocytes exhibited a precocious senescence and strongly reduced clonogenic potential. Moreover, KS cultures showed a strikingly increased percentage of aborted colonies (paraclones) already at early passages indicating an early depletion of stem cells. Immunoblotting analysis of KS keratinocyte extracts showed reduced levels of the stemness markers p63 and Bmi-1, upregulation of p16 and scant amounts of hypophosphorylated Rb protein, which indicated cell cycle-arrested status. Treatment of normal human primary keratinocytes with siRNA targeting kindlin-1 proved that its deficiency was directly responsible for p63, Bmi-1 and pRb downregulation and p16 induction. Our data directly implicate kindlin-1 in preventing premature senescence of keratinocytes. © 2013 The Authors. BJD © 2013 British Association of Dermatologists.

Fibroblast Growth Factor-Peptide Improves Barrier Function and Proliferation in Human Keratinocytes After Radiation

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

Zhang Kunzhong; Tian Yeping; Yin Liangjie

2011-09-01

Purpose: Epidermal keratinocytes, which can be severely damaged after ionizing radiation (IR), are rapid turnover cells that function as a barrier, protecting the host from pathogenic invasion and fluid loss. We tested fibroblast growth factor-peptide (FGF-P), a small peptide derived from the receptor-binding domain of FGF-2, as a potential mitigator of radiation effects via proliferation and the barrier function of keratinocytes. Methods and Materials: Keratinocytes isolated from neonatal foreskin were grown on transwells. After being exposed to 0, 5, or 10 Gy IR, the cells were treated with a vehicle or FGF-P. The permeability of IR cells was assessed bymore » using transepithelial electrical resistance (TEER) and a paracellular tracer flux of fluorescein isothiocyanate-conjugated bovine serum albumin (FITC-BSA) with Ussing chambers. The cell proliferation was measured with yellow tetrazolium salt (MTT) and tritiated thymidine ([{sup 3}H]-TdR) assays. The phosphorylation of extracellular signal-regulated kinases (ERK) was measured in an enzyme-linked immunosorbent (ELISA)-like assay, and the proteins related to tight junctions (TJ) and adherens junctions (AJ) were examined with Western blotting. We used a mouse model to assess the ability of FGF-P to promote the healing of skin {beta} burns created with a strontium applicator. Results: We found (1) FGF-P reduced the permeability of irradiated keratinocytes, as evidenced by increased TEER and decreased diffusion of FITC-BSA, both associated with the regulation of different proteins and levels of TJ and AJ; and (2) FGF-P enhanced the proliferation of irradiated keratinocytes, as evidenced by increased MTT activity and [{sup 3}H]-TdR incorporation, which was associated with activation of the ERK pathway; and (3) FGF-P promoted the healing of skin {beta} burns. Conclusions: FGF-P enhances the barrier function, including up-regulation of TJ proteins, increases proliferation of human keratinocytes, and accelerates

G-CSF suppresses allergic pulmonary inflammation, downmodulating cytokine, chemokine and eosinophil production.

PubMed

Queto, Túlio; Vasconcelos, Zilton F M; Luz, Ricardo Alves; Anselmo, Carina; Guiné, Ana Amélia A; e Silva, Patricia Machado R; Farache, Júlia; Cunha, José Marcos T; Bonomo, Adriana C; Gaspar-Elsas, Maria Ignez C; Xavier-Elsas, Pedro

2011-05-09

Granulocyte Colony-Stimulating Factor (G-CSF), which mobilizes hemopoietic stem cells (HSC), is believed to protect HSC graft recipients from graft-versus-host disease by enhancing Th2 cytokine secretion. Accordingly, G-CSF should aggravate Th2-dependent allergic pulmonary inflammation and the associated eosinophilia. We evaluated the effects of G-CSF in a model of allergic pulmonary inflammation. Allergic pulmonary inflammation was induced by repeated aerosol allergen challenge in ovalbumin-sensitized C57BL/6J mice. The effects of allergen challenge and of G-CSF pretreatment were evaluated by monitoring: a) eosinophilia and cytokine/chemokine content of bronchoalveolar lavage fluid, pulmonary interstitium, and blood; b) changes in airway resistance; and c) changes in bone-marrow eosinophil production. Contrary to expectations, G-CSF pretreatment neither induced nor enhanced allergic pulmonary inflammation. Instead, G-CSF: a) suppressed accumulation of infiltrating eosinophils in bronchoalveolar, peribronchial and perivascular spaces of challenged lungs; and b) prevented ovalbumin challenge-induced rises in airway resistance. G-CSF had multiple regulatory effects on cytokine and chemokine production: in bronchoalveolar lavage fluid, levels of IL-1 and IL-12 (p40), eotaxin and MIP-1a were decreased; in plasma, KC, a neutrophil chemoattractant, was increased, while IL-5 was decreased and eotaxin was unaffected. In bone-marrow, G-CSF: a) prevented the increase in bone-marrow eosinophil production induced by ovalbumin challenge of sensitized mice; and b) selectively stimulated neutrophil colony formation. These observations challenge the view that G-CSF deviates cytokine production towards a Th2 profile in vivo, and suggest that this neutrophil-selective hemopoietin affects eosinophilic inflammation by a combination of effects on lung cytokine production and bone-marrow hemopoiesis. Copyright © 2011 Elsevier Inc. All rights reserved.

Low-concentration hydrogen peroxide can upregulate keratinocyte intracellular calcium and PAR-2 expression in a human keratinocyte-melanocyte co-culture system.

PubMed

Li, Jian; Tang, Lu-Yan; Fu, Wen-Wen; Yuan, Jin; Sheng, You-Yu; Yang, Qin-Ping

2016-12-01

Hydrogen peroxide (H 2 O 2 ) may have a biphasic effect on melanin synthesis and melanosome transfer. High H 2 O 2 concentrations are involved in impaired melanosome transfer in vitiligo. However, low H 2 O 2 concentration promotes the beneficial proliferation and migration of melanocytes. The aim of this study was to explore low H 2 O 2 and its mechanism in melanosome transfer, protease-activated receptor-2 (PAR-2) expression and calcium balance. Melanosomes were fluorescein-labeled for clear visualization of their transfer. The expression of protease-activated receptor-2 (PAR-2) in keratinocytes was determined by western blot analysis. Flow cytometry was employed to evaluate the effects of H 2 O 2 on calcium levels in keratinocytes. Fluorescence microscopy showed the upregulation of melanosome transfer into keratinocytes following 0.3 mM H 2 O 2 treatment in the co-cultures rather than in the untreated control groups, which was associated with higher expression of PAR-2 protein and increased calcium concentration. The addition of a PAR-2 antagonist inhibited the positive activity of H 2 O 2 and calcium flow in keratinocytes. When calcium flow was blocked by a calcium chelator, the addition of H 2 O 2 did not increase the PAR-2 expression level in keratinocytes, therefore, inhibiting dendrite formation and melanosome transfer. Low H 2 O 2 concentration promotes melanosome transfer with increased PAR-2 expression level and calcium concentration in keratinocytes. In addition, the interaction between melanocytes and keratinocytes is more beneficial to enhance calcium levels in keratinocytes which mediate melanin transfer. Moreover, low H 2 O 2 concentration promotes dendrite formation, in which extracellular calcium and Par-2 were involved.

Stainless Steel NaK-Cooled Circuit (SNaKC) Fabrication and Assembly

NASA Technical Reports Server (NTRS)

Godfroy, Thomas J.

2007-01-01

An actively pumped Stainless Steel NaK Circuit (SNaKC) has been designed and fabricated by the Early Flight Fission Test Facility (EFF-TF) team at NASA's Marshall Space Flight Center. This circuit uses the eutectic mixture of sodium and potassium (NaK) as the working fluid building upon the experience and accomplishments of the SNAP reactor program from the late 1960's The SNaKC enables valuable experience and liquid metal test capability to be gained toward the goal of designing and building an affordable surface power reactor. The basic circuit components include a simulated reactor core a NaK to gas heat exchanger, an electromagnetic (EM) liquid metal pump, a liquid metal flow meter, an expansion reservoir and a drain/fill reservoir To maintain an oxygen free environment in the presence of NaK, an argon system is utilized. A helium and nitrogen system are utilized for core, pump, and heat exchanger operation. An additional rest section is available to enable special component testing m an elevated temperature actively pumped liquid metal environment. This paper summarizes the physical build of the SNaKC the gas and pressurization systems, vacuum systems, as well as instrumentation and control methods.

SMM-chemokines: a class of unnatural synthetic molecules as chemical probes of chemokine receptor biology and leads for therapeutic development.

PubMed

Kumar, Santosh; Choi, Won-Tak; Dong, Chang-Zhi; Madani, Navid; Tian, Shaomin; Liu, Dongxiang; Wang, Youli; Pesavento, James; Wang, Jun; Fan, Xuejun; Yuan, Jian; Fritzsche, Wayne R; An, Jing; Sodroski, Joseph G; Richman, Douglas D; Huang, Ziwei

2006-01-01

Chemokines and their receptors play important roles in numerous physiological and pathological processes. To develop natural chemokines into receptor probes and inhibitors of pathological processes, the lack of chemokine-receptor selectivity must be overcome. Here, we apply chemical synthesis and the concept of modular modifications to generate unnatural synthetically and modularly modified (SMM)-chemokines that have high receptor selectivity and affinity, and reduced toxicity. A proof of the concept was shown by transforming the nonselective viral macrophage inflammatory protein-II into new analogs with enhanced selectivity and potency for CXCR4 or CCR5, two principal coreceptors for human immunodeficiency virus (HIV)-1 entry. These new analogs provided insights into receptor binding and signaling mechanisms and acted as potent HIV-1 inhibitors. These results support the concept of SMM-chemokines for studying and controlling the function of other chemokine receptors.

Role of Complement C5 in Experimental Blunt Chest Trauma-Induced Septic Acute Lung Injury (ALI).

PubMed

Kalbitz, Miriam; Karbach, Michael; Braumueller, Sonja; Kellermann, Philipp; Gebhard, Florian; Huber-Lang, Markus; Perl, Mario

2016-01-01

Severe blunt chest trauma is associated with high mortality. Sepsis represents a serious risk factor for mortality in acute respiratory distress syndrome (ARDS). In septic patients with ARDS complement activation products were found to be elevated in the plasma. In single models like LPS or trauma complement has been studied to some degree, however in clinically highly relevant double hit models such as the one used here little data is available. Here, we hypothesized that absence of C5 is correlated with a decreased inflammatory response in trauma induced septic acute lung injury. 12 hrs after DH in mice the local and systemic cytokines and chemokines were quantified by multiplex bead array or ELISA, activated caspase-3 by western blot. Data were analyzed using one-way ANOVA followed by post-hoc Sidak's multiple comparison test (significance, p≤ 0.05). In lung tissue interleukin (IL)-6, monocyte chemo attractant protein-1 (MCP-1) and granulocyte-colony stimulating factor (G-CSF) was elevated in both C5-/- mice and wildtype littermates (wt), whereas caspase-3 was reduced in lungs after DH in C5-/- mice. Systemically, reduced keratinocyte-derived chemokine (KC) levels were observed after DH in C5-/- compared to wt mice. Locally, lung myeloperoxidase (MPO), protein, IL-6, MCP-1 and G-CSF in brochoalveolar lavage fluid (BALF) were elevated after DH in C5-/- compared to wt. In the complex but clinically relevant DH model the local and systemic inflammatory immune response features both, C5-dependent and C5-independent characteristics. Activation of caspase-3 in lung tissue after DH was C5-dependent whereas local inflammation in lung tissue was C5-independent.

Pulmonary exposure to diesel exhaust particles induces airway inflammation and cytokine expression in NC/Nga mice.

PubMed

Inoue, Ken-ichiro; Takano, Hirohisa; Yanagisawa, Rie; Ichinose, Takamichi; Shimada, Akinori; Yoshikawa, Toshikazu

2005-10-01

Although several studies have reported that diesel exhaust particles (DEP) affect cardiorespiratory health in animals and humans, the effect of DEP on animal models with spontaneous allergic disorders has been far less intensively studied. The Nc/Nga mouse is known to be a typical animal model for human atopic dermatitis (AD). In the present study, we investigated the effects of repeated pulmonary exposure to DEP on airway inflammation and cytokine expression in NC/Nga mice. The animals were randomized into two experimental groups that received vehicle or DEP by intratracheal instillation weekly for six weeks. Cellular profiles of bronchoalveolar lavage (BAL) fluid and expressions of cytokines and chemokines in both the BAL fluid and lung tissues were evaluated 24 h after the last instillation. The DEP challenge produced an increase in the numbers of total cells, neutrophils, and mononuclear cells in BAL fluid as compared to the vehicle challenge (P<0.01). DEP exposure significantly induced the lung expressions of interleukin (IL)-4, keratinocyte chemoattractant (KC), and macrophage inflammatory protein (MIP)-1alpha when compared to the vehicle challenge. These results indicate that intratracheal exposure to DEP induces the recruitment of inflammatory cells, at least partially, through the local expression of IL-4 and chemokines in NC/Nga mice.

Resistin deficiency in mice has no effect on pulmonary responses induced by acute ozone exposure

PubMed Central

Razvi, Shehla S.; Richards, Jeremy B.; Malik, Farhan; Cromar, Kevin R.; Price, Roger E.; Bell, Cynthia S.; Weng, Tingting; Atkins, Constance L.; Spencer, Chantal Y.; Cockerill, Katherine J.; Alexander, Amy L.; Blackburn, Michael R.; Alcorn, Joseph L.; Haque, Ikram U.

2015-01-01

Acute exposure to ozone (O3), an air pollutant, causes pulmonary inflammation, airway epithelial desquamation, and airway hyperresponsiveness (AHR). Pro-inflammatory cytokines—including IL-6 and ligands of chemokine (C-X-C motif) receptor 2 [keratinocyte chemoattractant (KC) and macrophage inflammatory protein (MIP)-2], TNF receptor 1 and 2 (TNF), and type I IL-1 receptor (IL-1α and IL-1β)—promote these sequelae. Human resistin, a pleiotropic hormone and cytokine, induces expression of IL-1α, IL-1β, IL-6, IL-8 (the human ortholog of murine KC and MIP-2), and TNF. Functional differences exist between human and murine resistin; yet given the aforementioned observations, we hypothesized that murine resistin promotes O3-induced lung pathology by inducing expression of the same inflammatory cytokines as human resistin. Consequently, we examined indexes of O3-induced lung pathology in wild-type and resistin-deficient mice following acute exposure to either filtered room air or O3. In wild-type mice, O3 increased bronchoalveolar lavage fluid (BALF) resistin. Furthermore, O3 increased lung tissue or BALF IL-1α, IL-6, KC, TNF, macrophages, neutrophils, and epithelial cells in wild-type and resistin-deficient mice. With the exception of KC, which was significantly greater in resistin-deficient compared with wild-type mice, no genotype-related differences in the other indexes existed following O3 exposure. O3 caused AHR to acetyl-β-methylcholine chloride (methacholine) in wild-type and resistin-deficient mice. However, genotype-related differences in airway responsiveness to methacholine were nonexistent subsequent to O3 exposure. Taken together, these data demonstrate that murine resistin is increased in the lungs of wild-type mice following acute O3 exposure but does not promote O3-induced lung pathology. PMID:26386120

Urine chemokines indicate pathogenic association of obesity with BPH/LUTS.

PubMed

Tyagi, Pradeep; Motley, Saundra S; Kashyap, Mahendra; Pore, Subrata; Gingrich, Jeffrey; Wang, Zhou; Yoshimura, Naoki; Fowke, Jay H

2015-07-01

High prevalence of lower urinary tract symptoms (LUTS) consistent with benign prostate hyperplasia (BPH) is associated with obesity and prostatic inflammation. Here, we investigated whether chemokines associated with obesity and prostatic inflammation can be measured in normally voided urine of BPH/LUTS patients to demonstrate the mechanistic association between obesity and BPH/LUTS. Frozen urine specimens of BPH/LUTS patients enrolled in the Nashville Men's Health Study were sent for blinded analysis to University of Pittsburgh. Thirty patients were blocked by their AUA-SI (>7 or ≤7) and prostatic enlargement (<40, 40-60, >60 cc). Clinical parameters including age, prostate size, and medications were derived from chart review. CXC chemokines (CXCL-1, CXCL-8, and CXCL-10), CC chemokines (CCL2 and CCL3), and sIL-1ra were measured in thawed urine using Luminex™ xMAP(®) technology and ELISA for NGF. Urinary CCL2 levels were several fold higher compared with the other six proteins, of which CCL3 was detectable in less than one-fourth of patients. Urine levels of sIL-1ra and CXCL-8 were significantly associated with increasing BMI and waist circumference in BPH patients. CXCL-8 showed a marginal association with overall AUA-SI scores, as well as obstructive (p = 0.08) symptom subscores. Prostate volume was inversely and marginally associated with urinary CXCL-10 (p = 0.09). Urine levels of CXCL-8, CXCL-10, and sIL-1ra were associated with varying degrees with LUTS severity, prostate size, and obesity, respectively. These findings in urine are consistent with past studies of chemokine levels from expressed prostatic secretions and demonstrate the potential of noninvasively measured chemokine in urine to objectively classify BPH/LUTS patients.

Platelet-Specific Chemokines Contribute to the Pathogenesis of Acute Lung Injury.

PubMed

Bdeir, Khalil; Gollomp, Kandace; Stasiak, Marta; Mei, Junjie; Papiewska-Pajak, Izabela; Zhao, Guohua; Worthen, G Scott; Cines, Douglas B; Poncz, Mortimer; Kowalska, M Anna

2017-02-01

Platelets and neutrophils contribute to the development of acute lung injury (ALI). However, the mechanism by which platelets make this contribution is incompletely understood. We investigated whether the two most abundant platelet chemokines, CXCL7, which induces neutrophil chemotaxis and activation, and CXCL4, which does neither, mediate ALI through complementary pathogenic pathways. To examine the role of platelet-derived chemokines in the pathogenesis of ALI using Cxcl7 -/- and Cxcl4 -/- knockout mice and mice that express human CXCL7 or CXCL4, we measured levels of chemokines in these mice. ALI was then induced by acid aspiration, and the severity of injury was evaluated by histology and by the presence of neutrophils and protein in the bronchoalveolar lavage fluid. Pulmonary vascular permeability was studied in vivo by measuring extravasation of fluorescently labeled dextran. Murine CXCL7, both recombinant and native protein released from platelets, can be N-terminally processed by cathepsin G to yield a biologically active CXCL7 fragment. Although Cxcl7 -/- mice are protected from lung injury through the preservation of endothelial/epithelial barrier function combined with impaired neutrophils transmigration, Cxcl4 -/- mice are protected through improved barrier function without affecting neutrophils transmigration to the airways. Sensitivity to ALI is restored by transgenic expression of CXCL7 or CXCL4. Platelet-derived CXCL7 and CXCL4 contribute to the pathogenesis of ALI through complementary effects on neutrophil chemotaxis and through activation and vascular permeability.

Astronaut Gregory Jarvis during KC-135 zero gravity training

NASA Image and Video Library

1985-01-25

S85-26106 (25 Jan. 1985) --- Astronaut Gregory Jarvis gets a familiarization session in weightlessness aboard a KC-135 "zero gravity" aircraft. Jarvis was originally assigned as payload specialist to STS-51D but was reassigned to STS-51L. Photo credit: NASA

Structural basis of receptor sulfotyrosine recognition by a CC chemokine: the N-terminal region of CCR3 bound to CCL11/eotaxin-1.

PubMed

Millard, Christopher J; Ludeman, Justin P; Canals, Meritxell; Bridgford, Jessica L; Hinds, Mark G; Clayton, Daniel J; Christopoulos, Arthur; Payne, Richard J; Stone, Martin J

2014-11-04

Trafficking of leukocytes in immune surveillance and inflammatory responses is activated by chemokines engaging their receptors. Sulfation of tyrosine residues in peptides derived from the eosinophil chemokine receptor CCR3 dramatically enhances binding to cognate chemokines. We report the structural basis of this recognition and affinity enhancement. We describe the structure of a CC chemokine (CCL11/eotaxin-1) bound to a fragment of a chemokine receptor: residues 8–23 of CCR3, including two sulfotyrosine residues. We also show that intact CCR3 is sulfated and sulfation enhances receptor activity. The CCR3 sulfotyrosine residues form hydrophobic, salt bridge and cation-p interactions with residues that are highly conserved in CC chemokines. However, the orientation of the chemokine relative to the receptor N terminus differs substantially from those observed for two CXC chemokines, suggesting that initial binding of the receptor sulfotyrosine residues guides subsequent steps in receptor activation, thereby influencing the receptor conformational changes and signaling.

Virus-encoded chemokine receptors--putative novel antiviral drug targets.

PubMed

Rosenkilde, Mette M

2005-01-01

Large DNA viruses, in particular herpes- and poxviruses, have evolved proteins that serve as mimics or decoys for endogenous proteins in the host. The chemokines and their receptors serve key functions in both innate and adaptive immunity through control of leukocyte trafficking, and have as such a paramount role in the antiviral immune responses. It is therefore not surprising that viruses have found ways to exploit and subvert the chemokine system by means of molecular mimicry. By ancient acts of molecular piracy and by induction and suppression of endogenous genes, viruses have utilized chemokines and their receptors to serve a variety of roles in viral life-cycle. This review focuses on the pharmacology of virus-encoded chemokine receptors, yet also the family of virus-encoded chemokines and chemokine-binding proteins will be touched upon. Key properties of the virus-encoded receptors, compared to their closest endogenous homologs, are interactions with a wider range of chemokines, which can act as agonists, antagonists and inverse agonists, and the exploitation of many signal transduction pathways. High constitutive activity is another key property of some--but not all--of these receptors. The chemokine receptors belong to the superfamily of G-protein coupled 7TM receptors that per se are excellent drug targets. At present, non-peptide antagonists have been developed against many chemokine receptors. The potentials of the virus-encoded chemokine receptors as drug targets--ie. as novel antiviral strategies--will be highlighted here together with the potentials of the virus-encoded chemokines and chemokine-binding proteins as novel anti-inflammatory biopharmaceutical strategies.

Selective Ablation of Ctip2/Bcl11b in Epidermal Keratinocytes Triggers Atopic Dermatitis-Like Skin Inflammatory Responses in Adult Mice

PubMed Central

Guha, Gunjan; Li, Shan; Kyrylkova, Kateryna; Kioussi, Chrissa; Leid, Mark; Ganguli-Indra, Gitali; Indra, Arup K.

2012-01-01

Background Ctip2 is crucial for epidermal homeostasis and protective barrier formation in developing mouse embryos. Selective ablation of Ctip2 in epidermis leads to increased transepidermal water loss (TEWL), impaired epidermal proliferation, terminal differentiation, as well as altered lipid composition during development. However, little is known about the role of Ctip2 in skin homeostasis in adult mice. Methodology/Principal Findings To study the role of Ctip2 in adult skin homeostasis, we utilized Ctip2ep−/− mouse model in which Ctip2 is selectively deleted in epidermal keratinocytes. Measurement of TEWL, followed by histological, immunohistochemical, and RT-qPCR analyses revealed an important role of Ctip2 in barrier maintenance and in regulating adult skin homeostasis. We demonstrated that keratinocytic ablation of Ctip2 leads to atopic dermatitis (AD)-like skin inflammation, characterized by alopecia, pruritus and scaling, as well as extensive infiltration of immune cells including T lymphocytes, mast cells, and eosinophils. We observed increased expression of T-helper 2 (Th2)-type cytokines and chemokines in the mutant skin, as well as systemic immune responses that share similarity with human AD patients. Furthermore, we discovered that thymic stromal lymphopoietin (TSLP) expression was significantly upregulated in the mutant epidermis as early as postnatal day 1 and ChIP assay revealed that TSLP is likely a direct transcriptional target of Ctip2 in epidermal keratinocytes. Conclusions/Significance Our data demonstrated a cell-autonomous role of Ctip2 in barrier maintenance and epidermal homeostasis in adult mice skin. We discovered a crucial non-cell autonomous role of keratinocytic Ctip2 in suppressing skin inflammatory responses by regulating the expression of Th2-type cytokines. It is likely that the epidermal hyperproliferation in the Ctip2-lacking epidermis may be secondary to the compensatory response of the adult epidermis that is defective in

Cryo-EM structure and biochemical analysis reveal the basis of the functional difference between human PI3KC3-C1 and -C2.

PubMed

Ma, Meisheng; Liu, Jun-Jie; Li, Yan; Huang, Yuwei; Ta, Na; Chen, Yang; Fu, Hua; Ye, Ming-Da; Ding, Yuehe; Huang, Weijiao; Wang, Jia; Dong, Meng-Qiu; Yu, Li; Wang, Hong-Wei

2017-08-01

Phosphatidylinositol 3-phosphate (PI3P) plays essential roles in vesicular trafficking, organelle biogenesis and autophagy. Two class III phosphatidylinositol 3-kinase (PI3KC3) complexes have been identified in mammals, the ATG14L complex (PI3KC3-C1) and the UVRAG complex (PI3KC3-C2). PI3KC3-C1 is crucial for autophagosome biogenesis, and PI3KC3-C2 is involved in various membrane trafficking events. Here we report the cryo-EM structures of human PI3KC3-C1 and PI3KC3-C2 at sub-nanometer resolution. The two structures share a common L-shaped overall architecture with distinct features. EM examination revealed that PI3KC3-C1 "stands up" on lipid monolayers, with the ATG14L BATs domain and the VPS34 C-terminal domain (CTD) directly contacting the membrane. Biochemical dissection indicated that the ATG14L BATs domain is responsible for membrane anchoring, whereas the CTD of VPS34 determines the orientation. Furthermore, PI3KC3-C2 binds much more weakly than PI3KC3-C1 to both PI-containing liposomes and purified endoplasmic reticulum (ER) vesicles, a property that is specifically determined by the ATG14L BATs domain. The in vivo ER localization analysis indicated that the BATs domain was required for ER localization of PI3KC3. We propose that the different lipid binding capacity is the key factor that differentiates the functions of PI3KC3-C1 and PI3KC3-C2 in autophagy.

Recruitment of bone marrow-derived cells to the periodontal ligament via the stromal cell-derived factor-1/C-X-C chemokine receptor type 4 axis.

PubMed

Kaku, M; Kitami, M; Rosales Rocabado, J M; Ida, T; Akiba, Y; Uoshima, K

2017-08-01

The periodontal ligament (PDL) is a non-mineralized connective tissue that exists between the alveolar bone and root surface cementum and plays important roles in tooth function. The PDL harbors a remarkable reserve of multipotent stem cells, which maintain various types of cells. However, the sources of these stem cells, other than their developmental origin, are not well understood. To elucidate the recruitment of bone marrow (BM)-derived stem cells in the PDL, green fluorescent protein (GFP)-expressing BM-derived cells were transplanted into the femoral BM of immunodeficient rats, and the distribution and expression of stem cell markers in the PDL were analyzed in vivo. To evaluate the functional significance of BM-derived cells to the PDL, tooth replantation was performed and the expression of stromal cell-derived factor (SDF)-1, a critical chemotactic signal for mesenchymal stem cell recruitment, was analyzed. To confirm the SDF-1-dependency of BM-derived cell migration to the PDL, PDL-conditioned medium (CM) was prepared, and BM-derived cell migration was analyzed using a transwell culture system. Four weeks after cell transplantation, GFP-positive cells were detected in the PDL, and some of them were also positive for stem cell markers (i.e., CD29, SSEA4, and αSMA). Seven days after tooth replantation, the number of GFP- and SDF-1-positive cells significantly increased in PDL. Concurrently, the concentration of SDF-1 and the number of colony-forming units of fibroblasts in peripheral blood were increased. BM-derived cell migration increased in PDL-CM and was inhibited by an inhibitor of C-X-C chemokine receptor type 4 (CXCR4), an SDF-1 receptor. These results indicate that stem cells and their progeny in PDL are not only derived from their developmental origin but are also supplied from the BM via the blood as the need arises. Moreover, this BM-derived cell recruitment appears to be regulated, at least partially, by the SDF-1/CXCR4 axis. © 2017 John Wiley

Malondialdehyde-acetaldehyde (MAA) adducted surfactant protein induced lung inflammation is mediated through scavenger receptor a (SR-A1).

PubMed

Sapkota, Muna; DeVasure, Jane M; Kharbanda, Kusum K; Wyatt, Todd A

2017-02-13

Co-exposure to cigarette smoke and alcohol leads to the generation of high concentrations of acetaldehyde and malondialdehyde in the lung. These aldehydes being highly electrophilic in nature react with biologically relevant proteins such as surfactant protein D (SPD) through a Schiff base reaction to generate SPD adducted malondialdehyde-acetaldehyde adduct (SPD-MAA) in mouse lung. SPD-MAA results in an increase in lung pro-inflammatory chemokine, keratinocyte chemoattractant (KC), and the recruitment of lung lavage neutrophils. Previous in vitro studies in bronchial epithelial cells and macrophages show that scavenger receptor A (SR-A1/CD204) is a major receptor for SPD-MAA. No studies have yet examined the in vivo role of SR-A1 in MAA-mediated lung inflammation. Therefore, we hypothesize that in the absence of SR-A1, MAA-induced inflammation in the lung is reduced or diminished. To test this hypothesis, C57BL/6 WT and SR-A1 KO mice were nasally instilled with 50 μg/mL of SPD-MAA for 3 weeks (wks). After 3 weeks, bronchoalveolar lavage (BAL) fluid was collected and assayed for a total cell count, a differential cell count and CXCL1 (KC) chemokine. Lung tissue sections were stained with hematoxylin and eosin (H&E) and antibodies to MAA adduct. Results showed that BAL cellularity and influx of neutrophils were decreased in SR-A1 KO mice as compared to WT following repetitive SPD-MAA exposure. MAA adduct staining in the lung epithelium was decreased in SR-A1 KO mice. In comparison to WT, no increase in CXCL1 was observed in BAL fluid from SR-A1 KO mice over time. Overall, the data demonstrate that SR-A1/CD204 plays an important role in SPD-MAA induced inflammation in lung.

Primed Mycobacterial Uveitis (PMU): Histologic and Cytokine Characterization of a Model of Uveitis in Rats.

PubMed

Pepple, Kathryn L; Rotkis, Lauren; Van Grol, Jennifer; Wilson, Leslie; Sandt, Angela; Lam, Deborah L; Carlson, Eric; Van Gelder, Russell N

2015-12-01

The purpose of this study was to compare the histologic features and cytokine profiles of experimental autoimmune uveitis (EAU) and a primed mycobacterial uveitis (PMU) model in rats. In Lewis rats, EAU was induced by immunization with interphotoreceptor binding protein peptide, and PMU was induced by immunization with a killed mycobacterial extract followed by intravitreal injection of the same extract. Clinical course, histology, and the cytokine profiles of the aqueous and vitreous were compared using multiplex bead fluorescence immunoassays. Primed mycobacterial uveitis generates inflammation 2 days after intravitreal injection and resolves spontaneously 14 days later. CD68+ lymphocytes are the predominant infiltrating cells and are found in the anterior chamber, surrounding the ciliary body and in the vitreous. In contrast to EAU, no choroidal infiltration or retinal destruction is noted. At the day of peak inflammation, C-X-C motif ligand 10 (CXCL10), IL-1β, IL-18, and leptin were induced in the aqueous of both models. Interleukin-6 was induced 2-fold in the aqueous of PMU but not EAU. Cytokines elevated in the aqueous of EAU exclusively include regulated on activation, normal T cell expressed and secreted (RANTES), lipopolysaccharide-induced CXC chemokine (LIX), growth-related oncogene/keratinocyte chemokine (GRO/KC), VEGF, monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1α (MIP-1α), and IL-17A. In the vitreous, CXCL10, GRO/KC, RANTES, and MIP-1α were elevated in both models. Interleukin-17A and IL-18 were elevated exclusively in EAU. Primed mycobacterial uveitis generates an acute anterior and intermediate uveitis without retinal involvement. Primed mycobacterial uveitis has a distinct proinflammatory cytokine profile compared with EAU, suggesting PMU is a good complementary model for study of immune-mediated uveitis. CXCL10, a proinflammatory cytokine, was increased in the aqueous and vitreous of both models and may be a

Non-coding Double-stranded RNA and Antimicrobial Peptide LL-37 Induce Growth Factor Expression from Keratinocytes and Endothelial Cells*

PubMed Central

Adase, Christopher A.; Borkowski, Andrew W.; Zhang, Ling-juan; Williams, Michael R.; Sato, Emi; Sanford, James A.

2016-01-01

A critical function for skin is that when damaged it must simultaneously identify the nature of the injury, repair barrier function, and limit the intrusion of pathogenic organisms. These needs are carried out through the detection of damage-associated molecular patterns (DAMPs) and a response that includes secretion of cytokines, chemokines, growth factors, and antimicrobial peptides (AMPs). In this study, we analyzed how non-coding double-stranded RNA (dsRNAs) act as a DAMP in the skin and how the human cathelicidin AMP LL-37 might influence growth factor production in response to this DAMP. dsRNA alone significantly increased the expression of multiple growth factors in keratinocytes, endothelial cells, and fibroblasts. Furthermore, RNA sequencing transcriptome analysis found that multiple growth factors increase when cells are exposed to both LL-37 and dsRNA, a condition that mimics normal wounding. Quantitative PCR and/or ELISA validated that growth factors expressed by keratinocytes in these conditions included, but were not limited to, basic fibroblast growth factor (FGF2), heparin-binding EGF-like growth factor (HBEGF), vascular endothelial growth factor C (VEGFC), betacellulin (BTC), EGF, epiregulin (EREG), and other members of the transforming growth factor β superfamily. These results identify a novel role for DAMPs and AMPs in the stimulation of repair and highlight the complex interactions involved in the wound environment. PMID:27048655

In vitro characterization of cutaneous immunotoxicity of immortalized human keratinocytes (HaCaT) exposed to reactive and disperse textile dyes.

PubMed

Leme, Daniela Morais; Sehr, Andrea; Grummt, Tamara; Gonçalves, Jenifer Pendiuk; Jacomasso, Thiago; Winnischofer, Sheila Maria Brochado; Potrich, Francine Bittencourt; Oliveira, Carolina Camargo de; Trindade, Edvaldo da Silva; de Oliveira, Danielle Palma

2018-05-01

Several synthetic dyes are used by textile industry for supplying the market of colored clothes. However, these chemicals have been associated with a variety of adverse human health effects, including textile dermatitis. Thus, there is a growing concern to identify textile dyes potentially as skin immunotoxicants. The aim of this in vitro study was to characterize the immunotoxic potential of reactive (Reactive Green 19 [RG19], Reactive Blue 2 [RB2], Reactive Black 5 [RB5]) and disperse (Disperse Red 1 [DR1]) textile dyes using a dermal cell line. For this purpose, a cell-based approach was conducted with immortalized human keratinocytes (KC) (HaCaT) using selected biomarkers of cutaneous inflammation including modulation of matrix metalloproteinases (MMP), oxidative stress such as reactive oxygen species (ROS) generation, and inflammatory cytokine profile. DR1 was the only dye able to trigger an immune response such as release of IL-12 cytokine, a potent co-stimulator of T helper 1 cell, which may be considered as a skin immunotoxicant. The reactive dyes including RB5 that were previously reported as skin sensitizers failed to induce inflammatory reactions under the conditions tested. The reactive dyes studied may pose a risk to human KC by induction of effects related to modulation of MMP-2 (RB5) and -9 (RB5 and RB2) and generation of ROS (RG19 and RB2). Thus, all these dyes need to be used with caution to avoid undesirable effects to consumers who may be exposed dermally.

Considerations in the improvement of human epidermal keratinocyte culture in vitro.

PubMed

Kaviani, Maryam; Geramizadeh, Bita; Rahsaz, Marjan; Marzban, Saeed

2015-04-01

Large-scale expansion of epidermal keratinocytes is essential in the application of these cells for severe burn treatment in patients. Therefore, this study was designed to evaluate various conditions in the expansion of human epidermal keratinocytes. The epidermis was separated from the dermis of skin samples using dispase. The epidermis was trypsinized for keratinocyte isolation. Keratinocytes were cultured in various conditions, with or without a human dermal fibroblast feeder layer, mitomycin C treatment, and different culture media. Our results suggest that keratinocytes cultured on a human dermal fibroblast feeder layer were grown for several passages. Extensive deformation and rapid deterioration were observed in the cultured cells without a feeder layer and in serum-free medium. Human dermal fibroblasts treated with mitomycin C can provide optimal conditions for proliferation of keratinocytes.

Differential Inflammatory-Response Kinetics of Human Keratinocytes upon Cytosolic RNA- and DNA-Fragment Induction.

PubMed

Danis, Judit; Janovák, Luca; Gubán, Barbara; Göblös, Anikó; Szabó, Kornélia; Kemény, Lajos; Bata-Csörgő, Zsuzsanna; Széll, Márta

2018-03-08

Keratinocytes are non-professional immune cells contributing actively to innate immune responses partially by reacting to a wide range of molecular patterns by activating pattern recognition receptors. Cytosolic nucleotide fragments as pathogen- or self-derived trigger factors are activating inflammasomes and inducing anti-viral signal transduction pathways as well as inducing expression of inflammatory cytokines. We aimed to compare the induced inflammatory reactions in three keratinocyte cell types-normal human epidermal keratinocytes, the HaCaT cell line and the HPV-KER cell line-upon exposure to the synthetic RNA and DNA analogues poly(I:C) and poly(dA:dT) to reveal the underlying signaling events. Both agents induced the expression of interleukin-6 and tumor necrosis factor α in all cell types; however, notable kinetic and expression level differences were found. Western blot analysis revealed rapid activation of the nuclear factor κB (NF-κB), mitogen activated protein kinase and signal transducers of activator of transcription (STAT) signal transduction pathways in keratinocytes upon poly(I:C) treatment, while poly(dA:dT) induced slower activation. Inhibition of NF-κB, p38, STAT-1 and STAT-3 signaling resulted in decreased cytokine expression, whereas inhibition of mitogen-activated protein kinase kinase 1/2 (MEK1/2) signaling showed a negative feedback role in both poly(I:C)- and poly(dA:dT)-induced cytokine expression. Based on our in vitro results nucleotide fragments are able to induce inflammatory reactions in keratinocytes, but with different rate and kinetics of cytokine expression, explained by faster activation of signaling routes by poly(I:C) than poly(dA:dT).

Differential Inflammatory-Response Kinetics of Human Keratinocytes upon Cytosolic RNA- and DNA-Fragment Induction

PubMed Central

Danis, Judit; Janovák, Luca; Gubán, Barbara; Göblös, Anikó; Szabó, Kornélia; Bata-Csörgő, Zsuzsanna; Széll, Márta

2018-01-01

Keratinocytes are non-professional immune cells contributing actively to innate immune responses partially by reacting to a wide range of molecular patterns by activating pattern recognition receptors. Cytosolic nucleotide fragments as pathogen- or self-derived trigger factors are activating inflammasomes and inducing anti-viral signal transduction pathways as well as inducing expression of inflammatory cytokines. We aimed to compare the induced inflammatory reactions in three keratinocyte cell types—normal human epidermal keratinocytes, the HaCaT cell line and the HPV-KER cell line—upon exposure to the synthetic RNA and DNA analogues poly(I:C) and poly(dA:dT) to reveal the underlying signaling events. Both agents induced the expression of interleukin-6 and tumor necrosis factor α in all cell types; however, notable kinetic and expression level differences were found. Western blot analysis revealed rapid activation of the nuclear factor κB (NF-κB), mitogen activated protein kinase and signal transducers of activator of transcription (STAT) signal transduction pathways in keratinocytes upon poly(I:C) treatment, while poly(dA:dT) induced slower activation. Inhibition of NF-κB, p38, STAT-1 and STAT-3 signaling resulted in decreased cytokine expression, whereas inhibition of mitogen-activated protein kinase kinase 1/2 (MEK1/2) signaling showed a negative feedback role in both poly(I:C)- and poly(dA:dT)-induced cytokine expression. Based on our in vitro results nucleotide fragments are able to induce inflammatory reactions in keratinocytes, but with different rate and kinetics of cytokine expression, explained by faster activation of signaling routes by poly(I:C) than poly(dA:dT). PMID:29518010

Chemokines expression during Leptospira interrogans serovar Copenhageni infection in resistant BALB/c and susceptible C3H/HeJ mice.

PubMed

da Silva, Josefa B; Ramos, Tatiane M V; de Franco, Marcelo; Paiva, Delhi; Ho, Paulo Lee; Martins, Elizabeth A L; Pereira, Martha M

2009-08-01

The role of innate immune responses in protection against leptospirosis remains unclear. We examined the expression of the chemokines CCL2/JE (MCP-1), CCL3/MIP-1 alpha (MIP-1 alpha) and CXCL1/KC (IL-8) regarding resistance and susceptibility to leptospirosis in experimental mice models BALB/c and C3H/HeJ, respectively. A virulent strain of Leptospira interrogans serovar Copenhageni was used in this study. Twenty-five animals of each mouse strain of C3H/HeJ and BALB/c, were infected intraperitoneally with 10(6) cells. Five un-infected animals of each strain were kept as control. Mortality of C3H/HeJ mouse was observed while BALB/c mice were asymptomatic. The presence of leptospire DNA in tissues of infected animals was demonstrated by PCR. Chemokines were measured in serum, spleen, liver, kidney and lung of both strains of animals using immunoenzymatic assay (ELISA). Elevations in the levels of chemokines MCP-1 and IL-8 occurred in all organs and sera of C3H/HeJ and BALB/c infected mice. The levels of MIP-1 alpha were lower when compared to MCP-1 and IL-8 in all analyzed organs, with a slight increase in liver and kidney. Our results indicate that the expression of inflammatory mediators can vary greatly, depending on the tissue and mouse strains. It is possible that the resistance to Leptospira can be partially correlated to the increase of MIP-1 alpha observed in BALB/c mice, while an increasing and a sustained expression of MCP-1 and IL-8 in the lungs of C3H/HeJ mice can be correlated to the severity and progression of leptospirosis.

Consequences of ChemR23 Heteromerization with the Chemokine Receptors CXCR4 and CCR7

PubMed Central

de Poorter, Cédric; Baertsoen, Kevin; Lannoy, Vincent; Parmentier, Marc; Springael, Jean-Yves

2013-01-01

Recent studies have shown that heteromerization of the chemokine receptors CCR2, CCR5 and CXCR4 is associated to negative binding cooperativity. In the present study, we build on these previous results, and investigate the consequences of chemokine receptor heteromerization with ChemR23, the receptor of chemerin, a leukocyte chemoattractant protein structurally unrelated to chemokines. We show, using BRET and HTRF assays, that ChemR23 forms homomers, and provide data suggesting that ChemR23 also forms heteromers with the chemokine receptors CCR7 and CXCR4. As previously described for other chemokine receptor heteromers, negative binding cooperativity was detected between ChemR23 and chemokine receptors, i.e. the ligands of one receptor competed for the binding of a specific tracer of the other. We also showed, using mouse bone marrow-derived dendritic cells prepared from wild-type and ChemR23 knockout mice, that ChemR23-specific ligands cross-inhibited CXCL12 binding on CXCR4 in a ChemR23-dependent manner, supporting the relevance of the ChemR23/CXCR4 interaction in native leukocytes. Finally, and in contrast to the situation encountered for other previously characterized CXCR4 heteromers, we showed that the CXCR4-specific antagonist AMD3100 did not cross-inhibit chemerin binding in cells co-expressing ChemR23 and CXCR4, demonstrating that cross-regulation by AMD3100 depends on the nature of receptor partners with which CXCR4 is co-expressed. PMID:23469143

Consequences of ChemR23 heteromerization with the chemokine receptors CXCR4 and CCR7.

PubMed

de Poorter, Cédric; Baertsoen, Kevin; Lannoy, Vincent; Parmentier, Marc; Springael, Jean-Yves

2013-01-01

Recent studies have shown that heteromerization of the chemokine receptors CCR2, CCR5 and CXCR4 is associated to negative binding cooperativity. In the present study, we build on these previous results, and investigate the consequences of chemokine receptor heteromerization with ChemR23, the receptor of chemerin, a leukocyte chemoattractant protein structurally unrelated to chemokines. We show, using BRET and HTRF assays, that ChemR23 forms homomers, and provide data suggesting that ChemR23 also forms heteromers with the chemokine receptors CCR7 and CXCR4. As previously described for other chemokine receptor heteromers, negative binding cooperativity was detected between ChemR23 and chemokine receptors, i.e. the ligands of one receptor competed for the binding of a specific tracer of the other. We also showed, using mouse bone marrow-derived dendritic cells prepared from wild-type and ChemR23 knockout mice, that ChemR23-specific ligands cross-inhibited CXCL12 binding on CXCR4 in a ChemR23-dependent manner, supporting the relevance of the ChemR23/CXCR4 interaction in native leukocytes. Finally, and in contrast to the situation encountered for other previously characterized CXCR4 heteromers, we showed that the CXCR4-specific antagonist AMD3100 did not cross-inhibit chemerin binding in cells co-expressing ChemR23 and CXCR4, demonstrating that cross-regulation by AMD3100 depends on the nature of receptor partners with which CXCR4 is co-expressed.

Citrullinated Chemokines in Rheumatoid Arthritis

DTIC Science & Technology

2014-10-01

fluids (SFs) compared to osteoarthritis (OA) and other inflammatory rheumatic diseases (OD) SFs, and its concentration correlates with RA disease ...osteoarthritis (OA), and other inflammatory rheumatic disease (OD) synovial fluids (SFs). The correlation between the citrullinated chemokine levels and...Objectives: Specific Aim 1: To determine how citrullinated chemokines compare in RA, vs. OA, vs. other rheumatic diseases (OD), vs. NLs. Major Task 1

Differential effects of the extracellular microenvironment on human embryonic stem cell differentiation into keratinocytes and their subsequent replicative life span.

PubMed

Movahednia, Mohammad Mehdi; Kidwai, Fahad Karim; Zou, Yu; Tong, Huei Jinn; Liu, Xiaochen; Islam, Intekhab; Toh, Wei Seong; Raghunath, Michael; Cao, Tong

2015-04-01

Culture microenvironment plays a critical role in the propagation and differentiation of human embryonic stem cells (hESCs) and their differentiated progenies. Although high efficiency of hESC differentiation to keratinocytes (hESC-Kert) has been achieved, little is known regarding the effects of early culture microenvironment and pertinent extracellular matrix (ECM) interactions during epidermal commitment on subsequent proliferative capacity of hESC-Kert. The aim of this study is to evaluate the effects of the different ECM microenvironments during hESC differentiation on subsequent replicative life span of hESC-Kert. In doing so, H1-hESCs were differentiated to keratinocytes (H1-Kert) in two differentiation systems. The first system employed autologous fibroblast feeder support, in which keratinocytes (H1-Kert(ACC)) were derived by coculture of hESCs with hESC-derived fibroblasts (H1-ebFs). The second system employed a novel decellularized matrix from H1-ebFs to create a dermoepidermal junction-like (DEJ) matrix. H1-Kert(AFF) were derived by differentiation of hESCs on the feeder-free system employing the DEJ matrix. Our study indicated that the feeder-free system with the use of DEJ matrix was more efficient in differentiation of hESCs toward epidermal progenitors. However, the feeder-free system was not sufficient to support the subsequent replicative capacity of differentiated keratinocytes. Of note, H1-Kert(AFF) showed limited replicative capacity with reduced telomere length and early cellular senescence. We further showed that the lack of cell-cell interactions during epidermal commitment led to heightened production of TGF-β1 by hESC-Kert during extended culture, which in turn was responsible for resulting in the limited replicative life span with cellular senescence of hESC-Kert derived under the feeder-free culture system. This study highlights for the first time the importance of the culture microenvironment and cell-ECM interactions during

The dependence of chemokine–glycosaminoglycan interactions on chemokine oligomerization

PubMed Central

Dyer, Douglas P; Salanga, Catherina L; Volkman, Brian F; Kawamura, Tetsuya; Handel, Tracy M

2016-01-01

Both chemokine oligomerization and binding to glycosaminoglycans (GAGs) are required for their function in cell recruitment. Interactions with GAGs facilitate the formation of chemokine gradients, which provide directional cues for migrating cells. In contrast, chemokine oligomerization is thought to contribute to the affinity of GAG interactions by providing a more extensive binding surface than single subunits alone. However, the importance of chemokine oligomerization to GAG binding has not been extensively quantified. Additionally, the ability of chemokines to form different oligomers has been suggested to impart specificity to GAG interactions, but most studies have been limited to heparin. In this study, several differentially oligomerizing chemokines (CCL2, CCL3, CCL5, CCL7, CXCL4, CXCL8, CXCL11 and CXCL12) and select oligomerization-deficient mutants were systematically characterized by surface plasmon resonance to determine their relative affinities for heparin, heparan sulfate (HS) and chondroitin sulfate-A (CS-A). Wild-type chemokines demonstrated a hierarchy of binding affinities for heparin and HS that was markedly dependent on oligomerization. These results were corroborated by their relative propensity to accumulate on cells and the critical role of oligomerization in cell presentation. CS-A was found to exhibit greater chemokine selectivity than heparin or HS, as it only bound a subset of chemokines; moreover, binding to CS-A was ablated with oligomerization-deficient mutants. Overall, this study definitively demonstrates the importance of oligomerization for chemokine–GAG interactions, and demonstrates diversity in the affinity and specificity of different chemokines for GAGs. These data support the idea that GAG interactions provide a mechanism for fine-tuning chemokine function. PMID:26582609

Platelet-Specific Chemokines Contribute to the Pathogenesis of Acute Lung Injury

PubMed Central

Bdeir, Khalil; Gollomp, Kandace; Stasiak, Marta; Mei, Junjie; Papiewska-Pajak, Izabela; Zhao, Guohua; Worthen, G. Scott; Cines, Douglas B.; Poncz, Mortimer

2017-01-01

Platelets and neutrophils contribute to the development of acute lung injury (ALI). However, the mechanism by which platelets make this contribution is incompletely understood. We investigated whether the two most abundant platelet chemokines, CXCL7, which induces neutrophil chemotaxis and activation, and CXCL4, which does neither, mediate ALI through complementary pathogenic pathways. To examine the role of platelet-derived chemokines in the pathogenesis of ALI using Cxcl7−/− and Cxcl4−/− knockout mice and mice that express human CXCL7 or CXCL4, we measured levels of chemokines in these mice. ALI was then induced by acid aspiration, and the severity of injury was evaluated by histology and by the presence of neutrophils and protein in the bronchoalveolar lavage fluid. Pulmonary vascular permeability was studied in vivo by measuring extravasation of fluorescently labeled dextran. Murine CXCL7, both recombinant and native protein released from platelets, can be N-terminally processed by cathepsin G to yield a biologically active CXCL7 fragment. Although Cxcl7−/− mice are protected from lung injury through the preservation of endothelial/epithelial barrier function combined with impaired neutrophils transmigration, Cxcl4−/− mice are protected through improved barrier function without affecting neutrophils transmigration to the airways. Sensitivity to ALI is restored by transgenic expression of CXCL7 or CXCL4. Platelet-derived CXCL7 and CXCL4 contribute to the pathogenesis of ALI through complementary effects on neutrophil chemotaxis and through activation and vascular permeability. PMID:27755915

Melatonin promotes diabetic wound healing in vitro by regulating keratinocyte activity

PubMed Central

Song, Ruipeng; Ren, Lijun; Ma, Haoli; Hu, Ruijing; Gao, Honghong; Wang, Li; Chen, Xuehui; Zhao, Zhigang; Liu, Jialin

2016-01-01

Diabetic patients are at high risk of developing delayed cutaneous wound healing. Proper keratinocyte proliferation and migration are crucial steps during re-epithelialization. Melatonin (Mel) accelerates wound repair in full-thickness incisional wounds; however, its role in diabetic wound healing is unknown. This study explored the role of Mel in diabetic wound healing in vitro by using high glucose (HG)-cultured keratinocytes. Mel reduced the HG-induced mRNA expression and release of pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin (IL)-1β, IL-6, and IL-8, in keratinocytes. Mel inhibited oxidative stress, as evidenced by reduced production of reactive oxygen species and malondialdehyde and increased activity of superoxide dismutase in HG-stimulated keratinocytes. Mel also inhibited HG-induced nucleotide binding oligomerization domain-like receptor family pyrin domain-containing 3 inflammasome activation in keratinocytes. HG-induced reduced migration and proliferation and increased apoptosis of keratinocytes were counteracted by Mel treatment. The pro-proliferative, pro-migratory, and anti-apoptotic effects of Mel on HG-treated keratinocytes were mediated by extracellular signal-regulated kinase signaling pathway. Results collectively suggested that Mel is an alternative therapeutic strategy to ameliorate poor condition for diabetic wound healing by regulating keratinocyte activity. PMID:27904671

Chemokine Involvement in Fetal and Adult Wound Healing

PubMed Central

Balaji, Swathi; Watson, Carey L.; Ranjan, Rajeev; King, Alice; Bollyky, Paul L.; Keswani, Sundeep G.

2015-01-01

Significance: Fetal wounds heal with a regenerative phenotype that is indistinguishable from surrounding skin with restored skin integrity. Compared to this benchmark, all postnatal wound healing is impaired and characterized by scar formation. The biologic basis of the fetal regenerative phenotype can serve as a roadmap to recapitulating regenerative repair in adult wounds. Reduced leukocyte infiltration, likely mediated, in part, through changes in the chemokine milieu, is a fundamental feature of fetal wound healing. Recent Advances: The contributions of chemokines to wound healing are a topic of active investigation. Recent discoveries have opened the possibility of targeting chemokines therapeutically to treat disease processes and improve healing capability, including the possibility of achieving a scarless phenotype in postnatal wounds. Critical Issues: Successful wound healing is a complex process, in which there is a significant interplay between multiple cell types, signaling molecules, growth factors, and extracellular matrix. Chemokines play a crucial role in this interplay and have been shown to have different effects in various stages of the healing process. Understanding how these chemokines are locally produced and regulated during wound healing and how the chemokine milieu differs in fetal versus postnatal wounds may help us identify ways in which we can target chemokine pathways. Future Directions: Further studies on the role of chemokines and their role in the healing process will greatly advance the potential for using these molecules as therapeutic targets. PMID:26543680

International Union of Pharmacology. LXXXIX. Update on the Extended Family of Chemokine Receptors and Introducing a New Nomenclature for Atypical Chemokine Receptors

PubMed Central

Bachelerie, Francoise; Ben-Baruch, Adit; Burkhardt, Amanda M.; Combadiere, Christophe; Farber, Joshua M.; Graham, Gerard J.; Horuk, Richard; Sparre-Ulrich, Alexander Hovard; Locati, Massimo; Luster, Andrew D.; Mantovani, Alberto; Matsushima, Kouji; Nibbs, Robert; Nomiyama, Hisayuki; Power, Christine A.; Proudfoot, Amanda E. I.; Rosenkilde, Mette M.; Rot, Antal; Sozzani, Silvano; Thelen, Marcus; Yoshie, Osamu; Zlotnik, Albert

2014-01-01

Sixteen years ago, the Nomenclature Committee of the International Union of Pharmacology approved a system for naming human seven-transmembrane (7TM) G protein-coupled chemokine receptors, the large family of leukocyte chemoattractant receptors that regulates immune system development and function, in large part by mediating leukocyte trafficking. This was announced in Pharmacological Reviews in a major overview of the first decade of research in this field [Murphy PM, Baggiolini M, Charo IF, Hébert CA, Horuk R, Matsushima K, Miller LH, Oppenheim JJ, and Power CA (2000) Pharmacol Rev 52:145–176]. Since then, several new receptors have been discovered, and major advances have been made for the others in many areas, including structural biology, signal transduction mechanisms, biology, and pharmacology. New and diverse roles have been identified in infection, immunity, inflammation, development, cancer, and other areas. The first two drugs acting at chemokine receptors have been approved by the U.S. Food and Drug Administration (FDA), maraviroc targeting CCR5 in human immunodeficiency virus (HIV)/AIDS, and plerixafor targeting CXCR4 for stem cell mobilization for transplantation in cancer, and other candidates are now undergoing pivotal clinical trials for diverse disease indications. In addition, a subfamily of atypical chemokine receptors has emerged that may signal through arrestins instead of G proteins to act as chemokine scavengers, and many microbial and invertebrate G protein-coupled chemokine receptors and soluble chemokine-binding proteins have been described. Here, we review this extended family of chemokine receptors and chemokine-binding proteins at the basic, translational, and clinical levels, including an update on drug development. We also introduce a new nomenclature for atypical chemokine receptors with the stem ACKR (atypical chemokine receptor) approved by the Nomenclature Committee of the International Union of Pharmacology and the Human

Smad4 disruption accelerates keratinocyte reepithelialization in murine cutaneous wound repair.

PubMed

Yang, Leilei; Li, Wenlong; Wang, Shaoxia; Wang, Lijuan; Li, Yang; Yang, Xiao; Peng, Ruiyun

2012-10-01

Keratinocyte reepithelialization is a rate-limiting event in cutaneous wound repair, which involves the migration and proliferation of keratinocytes to cover the denuded dermal surface. Transforming growth factor-β1 (TGF-β1) has the ability to induce epithelial cell migration while inhibiting proliferation, and controversial results have been generated regarding the effect of TGF-β signaling on reepithelialization. In this study, full-thickness skin wounds were made in keratinocyte-specific Smad4 knockout and the control mice. The wound closure, reepithelialization, keratinocyte proliferation, myofibroblast numbers and collagen deposition of were assessed. The results showed that the proliferation of keratinocytes increased, which accelerated the reepithelialization, and led to faster wound repair in the epidermis of Smad4 mutant mice. Upregulation of keratin 17, 14-3-3 sigma and phosphorylated AKT in the hyperproliferative epidermis may be correlated with the accelerated reepithelialization. We conclude that Smad4 plays an inhibitory role in the keratinocyte-mediated reepithelialization of wound healing.

A Central Role for Heme Oxygenase-1 in the Control of Intestinal Epithelial Chemokine Expression.

PubMed

Onyiah, Joseph C; Schaefer, Rachel E M; Colgan, Sean P

2018-05-23

In mucosal inflammatory disorders, the protective influence of heme oxygenase-1 (HO-1) and its metabolic byproducts, carbon monoxide (CO) and biliverdin, is a topic of significant interest. Mechanisms under investigation include the regulation of macrophage function and mucosal cytokine expression. While there is an increasing recognition of the importance of epithelial-derived factors in the maintenance of intestinal mucosal homeostasis, the contribution of intestinal epithelial cell (IEC) HO-1 on inflammatory responses has not previously been investigated. We examined the influence of modulating HO-1 expression on the inflammatory response of human IECs. Engineered deficiency of HO-1 in Caco-2 and T84 IECs led to increased proinflammatory chemokine expression in response to pathogenic bacteria and inflammatory cytokine stimulation. Crosstalk with activated leukocytes also led to increased chemokine expression in HO-1-deficient cells in an IL-1β dependent manner. Treatment of Caco-2 cells with a pharmacological inducer of HO-1 led to the inhibition of chemokine expression. Mechanistic studies suggest that HO-1 and HO-1-related transcription factors, but not HO-1 metabolic products, are partly responsible for the influence of HO-1 on chemokine expression. In conclusion, our data identify HO-1 as a central regulator of IEC chemokine expression that may contribute to homeo-stasis in the intestinal mucosa. © 2018 S. Karger AG, Basel.

Revised tuning of Ocean Drilling Program Site 964 and KC01B (Mediterranean) and implications for the δ18O, tephra, calcareous nannofossil, and geomagnetic reversal chronologies of the past 1.1 Myr

NASA Astrophysics Data System (ADS)

Lourens, Lucas J.

2004-09-01

High-resolution color reflectance records of KC01 and KC01B (Calabrian Ridge, Ionian Sea) are presented and compared with a modified spliced high-resolution color reflectance record of Ocean Drilling Program (ODP) Site 964. This comparison revealed that KC01B is characterized by intensive deformation between ~27 and 28.5 m piston depth and that some sapropels are tectonically reduced in thickness. Moreover, the piston coring has caused considerable stretching in the top of KC01 and KC01B. Using a new splice of ODP Site 964 as guide, previous astronomical tuned timescales of KC01B and ODP Site 964 were evaluated. This evaluation resulted in a new sapropel-based astronomical timescale for the last 1.1 Myr. The new timescale implies a much more uniform change in sedimentation rate for the Ionian Sea cores. Two prominent excursions to lighter values in the δ18O record of the planktonic foraminiferal species Globigerinoides ruber occur during marine isotopic stages 12 and 16 applying the new timescale. These shifts correspond with maxima in obliquity and are punctuated by minima in the precession cycle. They are absent in global ice volume records and are interpreted as reflecting a (summer) low-salinity surface water lens that floats on top of extremely saline intermediate and deep waters at times of the very low sea levels during these glacial periods. All biostratigraphic and magnetostratigraphic events found in KC01B and ODP Site 964 were re-dated according to the new timescale, and the ages of 33 tephra layers were reviewed. The new ages for the Calabrian Ridge 2 and 3 magnetic events in the Brunhes are concordant with minima in the global Sint800 composite record, derived from worldwide deep-sea records of relative paleointensity and have been attributed to the Big Lost and La Palma excursions, respectively.

Mechanisms and Implications of Air Pollution Particle Associations with Chemokines

PubMed Central

Seagrave, JeanClare

2008-01-01

Inflammation induced by inhalation of air pollutant particles has been implicated as a mechanism for the adverse health effects associated with exposure to air pollution. The inflammatory response is associated with upregulation of various pro-inflammatory cytokines and chemokines. We have previously shown that diesel exhaust particles (DEP), a significant constituent of air pollution particulate matter in many urban areas, bind and concentrate IL-8, an important human neutrophil-attracting chemokine, and that the chemokine remains biologically active. In this report, we examine possible mechanisms of this association and the effects on clearance of the chemokine. The binding appears to be the result of ionic interactions between negatively charged particles and positively charged chemokine molecules, possibly combined with intercalation into small pores in the particles. The association is not limited to diesel exhaust particles and IL-8: several other particle types also adsorb the chemokine and several other cytokines are adsorbed onto the diesel particles. However, there are wide ranges in the effectiveness of various particle types and various cytokines. Finally, male Fisher 344 rats were intratracheally instilled with chemokine alone or combined with diesel exhaust or silica particles under isofluorane anesthesia. In contrast to silica particles, which do not bind the chemokine, the presence of diesel exhaust particles, which bind the chemokine, prolonged the retention of the chemokine. PMID:18755206

Chemokine Signaling in Allergic Contact Dermatitis: Toward Targeted Therapies.

PubMed

Smith, Jeffrey S; Rajagopal, Sudarshan; Atwater, Amber Reck

2018-06-22

Allergic contact dermatitis (ACD) is a common skin disease that results in significant cost and morbidity. Despite its high prevalence, therapeutic options are limited. Allergic contact dermatitis is regulated primarily by T cells within the adaptive immune system, but also by natural killer and innate lymphoid cells within the innate immune system. The chemokine receptor system, consisting of chemokine peptides and chemokine G protein-coupled receptors, is a critical regulator of inflammatory processes such as ACD. Specific chemokine signaling pathways are selectively up-regulated in ACD, most prominently CXCR3 and its endogenous chemokines CXCL9, CXCL10, and CXCL11. Recent research demonstrates that these 3 chemokines are not redundant and indeed activate distinct intracellular signaling profiles such as those activated by heterotrimeric G proteins and β-arrestin adapter proteins. Such differential signaling provides an attractive therapeutic target for novel ACD therapies and other inflammatory diseases.

Chemosensory Information Processing between Keratinocytes and Trigeminal Neurons

PubMed Central

Sondersorg, Anna Christina; Busse, Daniela; Kyereme, Jessica; Rothermel, Markus; Neufang, Gitta; Gisselmann, Günter; Hatt, Hanns; Conrad, Heike

2014-01-01

Trigeminal fibers terminate within the facial mucosa and skin and transmit tactile, proprioceptive, chemical, and nociceptive sensations. Trigeminal sensations can arise from the direct stimulation of intraepithelial free nerve endings or indirectly through information transmission from adjacent cells at the peripheral innervation area. For mechanical and thermal cues, communication processes between skin cells and somatosensory neurons have already been suggested. High concentrations of most odors typically provoke trigeminal sensations in vivo but surprisingly fail to activate trigeminal neuron monocultures. This fact favors the hypothesis that epithelial cells may participate in chemodetection and subsequently transmit signals to neighboring trigeminal fibers. Keratinocytes, the major cell type of the epidermis, express various receptors that enable reactions to multiple environmental stimuli. Here, using a co-culture approach, we show for the first time that exposure to the odorant chemicals induces a chemical communication between human HaCaT keratinocytes and mouse trigeminal neurons. Moreover, a supernatant analysis of stimulated keratinocytes and subsequent blocking experiments with pyrodoxalphosphate-6-azophenyl-2′,4′-disulfonate revealed that ATP serves as the mediating transmitter molecule released from skin cells after odor stimulation. We show that the ATP release resulting from Javanol® stimulation of keratinocytes was mediated by pannexins. Consequently, keratinocytes act as chemosensors linking the environment and the trigeminal system via ATP signaling. PMID:24790106

Environmental Factors Impacting Bone-Relevant Chemokines

PubMed Central

Smith, Justin T.; Schneider, Andrew D.; Katchko, Karina M.; Yun, Chawon; Hsu, Erin L.

2017-01-01

Chemokines play an important role in normal bone physiology and the pathophysiology of many bone diseases. The recent increased focus on the individual roles of this class of proteins in the context of bone has shown that members of the two major chemokine subfamilies—CC and CXC—support or promote the formation of new bone and the remodeling of existing bone in response to a myriad of stimuli. These chemotactic molecules are crucial in orchestrating appropriate cellular homing, osteoblastogenesis, and osteoclastogenesis during normal bone repair. Bone healing is a complex cascade of carefully regulated processes, including inflammation, progenitor cell recruitment, differentiation, and remodeling. The extensive role of chemokines in these processes and the known links between environmental contaminants and chemokine expression/activity leaves ample opportunity for disruption of bone healing by environmental factors. However, despite increased clinical awareness, the potential impact of many of these environmental factors on bone-related chemokines is still ill defined. A great deal of focus has been placed on environmental exposure to various endocrine disruptors (bisphenol A, phthalate esters, etc.), volatile organic compounds, dioxins, and heavy metals, though mainly in other tissues. Awareness of the impact of other less well-studied bone toxicants, such as fluoride, mold and fungal toxins, asbestos, and chlorine, is also reviewed. In many cases, the literature on these toxins in osteogenic models is lacking. However, research focused on their effects in other tissues and cell lines provides clues for where future resources could be best utilized. This review aims to serve as a current and exhaustive resource detailing the known links between several classes of high-interest environmental pollutants and their interaction with the chemokines relevant to bone healing. PMID:28261155

HIV/AIDS Vaccine Candidates Based on Replication-Competent Recombinant Poxvirus NYVAC-C-KC Expressing Trimeric gp140 and Gag-Derived Virus-Like Particles or Lacking the Viral Molecule B19 That Inhibits Type I Interferon Activate Relevant HIV-1-Specific B and T Cell Immune Functions in Nonhuman Primates

PubMed Central

García-Arriaza, Juan; Perdiguero, Beatriz; Heeney, Jonathan L.; Seaman, Michael S.; Montefiori, David C.; Yates, Nicole L.; Tomaras, Georgia D.; Ferrari, Guido; Foulds, Kathryn E.; Roederer, Mario; Self, Steven G.; Borate, Bhavesh; Gottardo, Raphael; Phogat, Sanjay; Tartaglia, Jim; Barnett, Susan W.; Burke, Brian; Cristillo, Anthony D.; Weiss, Deborah E.; Lee, Carter; Kibler, Karen V.; Jacobs, Bertram L.; Wagner, Ralf; Ding, Song; Pantaleo, Giuseppe

2017-01-01

ABSTRACT The nonreplicating attenuated poxvirus vector NYVAC expressing clade C(CN54) HIV-1 Env(gp120) and Gag-Pol-Nef antigens (NYVAC-C) showed limited immunogenicity in phase I clinical trials. To enhance the capacity of the NYVAC vector to trigger broad humoral responses and a more balanced activation of CD4+ and CD8+ T cells, here we compared the HIV-1-specific immunogenicity elicited in nonhuman primates immunized with two replicating NYVAC vectors that have been modified by the insertion of the K1L and C7L vaccinia virus host range genes and express the clade C(ZM96) trimeric HIV-1 gp140 protein or a Gag(ZM96)-Pol-Nef(CN54) polyprotein as Gag-derived virus-like particles (termed NYVAC-C-KC). Additionally, one NYVAC-C-KC vector was generated by deleting the viral gene B19R, an inhibitor of the type I interferon response (NYVAC-C-KC-ΔB19R). An immunization protocol mimicking that of the RV144 phase III clinical trial was used. Two groups of macaques received two doses of the corresponding NYVAC-C-KC vectors (weeks 0 and 4) and booster doses with NYVAC-C-KC vectors plus the clade C HIV-1 gp120 protein (weeks 12 and 24). The two replicating NYVAC-C-KC vectors induced enhanced and similar HIV-1-specific CD4+ and CD8+ T cell responses, similar levels of binding IgG antibodies, low levels of IgA antibodies, and high levels of antibody-dependent cellular cytotoxicity responses and HIV-1-neutralizing antibodies. Small differences within the NYVAC-C-KC-ΔB19R group were seen in the magnitude of CD4+ and CD8+ T cells, the induction of some cytokines, and the neutralization of some HIV-1 isolates. Thus, replication-competent NYVAC-C-KC vectors acquired relevant immunological properties as vaccine candidates against HIV/AIDS, and the viral B19 molecule exerts some control of immune functions. IMPORTANCE It is of special importance to find a safe and effective HIV/AIDS vaccine that can induce strong and broad T cell and humoral immune responses correlating with HIV-1

Stimulatory effect of boron and manganese salts on keratinocyte migration.

PubMed

Chebassier, Nathalie; Ouijja, El Houssein; Viegas, Isabelle; Dreno, Brigitte

2004-01-01

Keratinocyte proliferation and migration are essential for the reconstruction of the cutaneous barrier after skin injury. Interestingly, thermal waters which are rich in trace elements (e.g. boron and manganese), are known to be able to improve wound healing. In order to understand the mechanism of action of this effect, our study investigated the in vitro modulation of keratinocyte migration and proliferation by boron and manganese salts, which are present in high concentrations in a thermal water (Saint Gervais). Our in vitro study demonstrated that incubating keratinocytes for 24 h with boron salts at concentrations between 0.5 and 10 microg/ml or manganese salts at concentrations between 0.1 and 1.5 microg/ml accelerated wound closure compared with control medium (+20%). As this acceleration was not related to an increase in keratinocyte proliferation we suggest that boron and manganese act on wound healing mainly by increasing the migration of keratinocytes.

Keratinocyte differentiation is regulated by the Rho and ROCK signaling pathway.

PubMed

McMullan, Rachel; Lax, Siân; Robertson, Vicki H; Radford, David J; Broad, Simon; Watt, Fiona M; Rowles, Alison; Croft, Daniel R; Olson, Michael F; Hotchin, Neil A

2003-12-16

The epidermis comprises multiple layers of specialized epithelial cells called keratinocytes. As cells are lost from the outermost epidermal layers, they are replaced through terminal differentiation, in which keratinocytes of the basal layer cease proliferating, migrate upwards, and eventually reach the outermost cornified layers. Normal homeostasis of the epidermis requires that the balance between proliferation and differentiation be tightly regulated. The GTP binding protein RhoA plays a fundamental role in the regulation of the actin cytoskeleton and in the adhesion events that are critically important to normal tissue homeostasis. Two central mediators of the signals from RhoA are the ROCK serine/threonine kinases ROCK-I and ROCK-II. We have analyzed ROCK's role in the regulation of epidermal keratinocyte function by using a pharmacological inhibitor and expressing conditionally active or inactive forms of ROCK-II in primary human keratinocytes. We report that blocking ROCK function results in inhibition of keratinocyte terminal differentiation and an increase in cell proliferation. In contrast, activation of ROCK-II in keratinocytes results in cell cycle arrest and an increase in the expression of a number of genes associated with terminal differentiation. Thus, these results indicate that ROCK plays a critical role in regulating the balance between proliferation and differentiation in human keratinocytes.

General purpose free floating platform for KC-135 flight experimentation

NASA Technical Reports Server (NTRS)

Borchers, Bruce A.; Yendler, Boris S.; Kliss, Mark H.; Gonzales, Andrew A.; Edwards, Mark T.

1994-01-01

The Controlled Ecological Life Support Systems (CELSS) program is evaluating higher plants as a means of providing life support functions aboard space craft. These plant systems will be capable of regenerating air and water while meeting some of the food requirements of the crew. In order to grow plants in space, a series of systems are required to provide the necessary plant support functions. Some of the systems required for CELSS experiments are such that is is likely that existing technologies will require refinement, or novel technologies will need to be developed. To evaluate and test these technologies, a series of KC-135 precursor flights are being proposed. A general purpose free floating experiment platform is being developed to allow the KC-135 flights to be used to their fullest. This paper will outline the basic design for the CELSS Free Floating Test Bed (FFTB), and the requirements for the individual subsystems. Several preliminary experiments suitable for the free floater will also be discussed.

[Detection of stable expression of human interlukin-2 gene in transfected keratinocytes].

PubMed

Liao, W; Liu, Y; Ye, L

1999-09-01

To investigate the stable expression and secretion of human interlukin-2 gene in transfected keratinocytes. Keratinocytes were transfected with lipofectamine and selected by G418. Then the samples were analyzed with the techniques of DNA dot blot, RNA dot blot, hybridization in situ, immunohistochemistry, Western blot and MTT. The positive signals were observed in transfected keratinocytes by DNA dot blot, RNA dot blot, hybridization in situ and immunohistochemistry. With Western blot analysis, a specific band exhibiting a molecular weight of 15,000 was detected in transfected keratinocytes, which was in acordance with that of IL-2. The expression of IL-2 can maintain for up to 1 month. The amounts of IL-2 in the supernatants of two and four passages transfected keratinocytes were 27.7 U/ml and 15.0 U/ml, respectively. Keratinocytes have the potential for stable gene expression and secretion of active transgene products. Thus, it is possible to use keratinocytes as a target cell for gene transfection, gene expression and even gene therapy.

Anti-inflammatory potential of alginic acid from Sargassum horneri against urban aerosol-induced inflammatory responses in keratinocytes and macrophages.

PubMed

Fernando, I P Shanura; Jayawardena, Thilina U; Sanjeewa, K K Asanka; Wang, Lei; Jeon, You-Jin; Lee, Won Woo

2018-09-30

The airborne particulate pollutants originating in the deserts of Mongolia and China which becomes contaminated with industrial effluents and traffic emissions while moving with the wind currents towards East Asia has recently become a serious environmental and health issue in the region. They cause asthma, collateral lung tissue damage, oxidative stress, allergic reactions, and inflammation. The current study was undertaken to evaluate the protective effects of alginate extracted from the invasive alga Sargassum horneri (SHA) against fine dust collected from Beijing, China (Chinese fine dust; CFD). It was found that CFD induces inflammation in HaCaT keratinocytes and inhibits macrophage activation. All of the particulate matter (PM) comprising CFD was < PM13 majority being < PM2.5 which is defined for mineral elements and polycyclic aromatic hydrocarbons. SHA attenuated PGE 2 levels in CFD-induced HaCaT keratinocytes. The IC 50 for SHA was 36.63 ± 4.11 µg mL -l . SHA also reduced the levels of COX-2, IL-6, and TNF-α, and inhibited certain key molecular mediators of the NF-κB and MAPK pathways in keratinocytes. SHA substantially reduced the levels of CFD-derived metal ions like Pb 2+ and Ca 2+ in keratinocytes attributable to its metal ion chelating properties. CFD-induced HaCaT keratinocyte culture media increased inflammatory responses in RAW 264.7 macrophages. These cells presented with increased levels of NO, iNOS, COX-2, PGE 2 , and pro-inflammatory cytokines. It was found that the aforementioned effects could be reversed in RAW 264.7 macrophages when keratinocytes were treated with SHA. Therefore, SHA could be used against fine dust-induced inflammation in keratinocytes. Copyright © 2018 Elsevier Inc. All rights reserved.

Synergistic inhibition in vivo of bone marrow myeloid progenitors by myelosuppressive chemokines and chemokine-accelerated recovery of progenitors after treatment of mice with Ara-C.

PubMed

Broxmeyer, Hal E; Pelus, Louis M; Kim, Chang H; Hangoc, Giao; Cooper, Scott; Hromas, Robert

2006-08-01

Selected chemokines suppress proliferation of hematopoietic progenitor cells (HPCs) in vitro; some of these have demonstrated inhibition of myelopoiesis in vivo. Because myelosuppressive chemokines synergize in vitro with other myelosuppressive chemokines, we sought to determine whether additional chemokines active in vitro were myelosuppressive in vivo and whether combinations of myelosuppressive chemokines synergized in vivo to dampen myelopoiesis. We also evaluated three chemokines in vivo for myeloprotection against Ara-C-induced decreases in HPCs. C3H/HeJ mice were used for analysis of in vivo influence of chemokines, with the end points being effects on absolute numbers and cycling status of HPCs. When used alone, CCL2, CCL3, CCL19, CCL20, CXCL4, CXCL5, CXCL8, CXCL9, and XCL1 caused dose-dependent significant decreases in absolute numbers and cycling status of HPCs in vivo. The following combinations of two chemokines resulted in in vivo myelosuppression at concentrations much lower than that induced by each chemokine alone: CCL3 plus either CXCL8 or CXCL4, CXCL8 plus CXCL4, CCL2 plus either CCL20 or CXCL9, CCL20 plus CXCL9, CXCL5 plus either XCL1 or CCL19, XCL1 plus CCL19, and CCL3 plus CCL19. Also, mice injected with CXCL8, CXCL4, or the chimeric CXCL8/CXCL4 protein CXCL8M1 manifested accelerated recovery of absolute numbers of HPCs in response to the toxic effects of Ara-C administration. A number of chemokines shown previously to manifest inhibitory effects in vitro for proliferation of HPCs are now demonstrated to also induce myelosuppression in vivo. Moreover, combinations of low dosages of two myelosuppressive chemokines when administered together demonstrate synergistic suppression in vivo. Additionally, chemokines, including a CXCL8M1 chimeric protein previously shown to manifest enhanced suppression of HPC proliferation in vitro and in vivo, accelerate HPC recovery after treatment of mice with Ara-C. These results may be of use for future clinical

Materials science on parabolic aircraft: The FY 1987-1989 KC-135 microgravity test program

NASA Technical Reports Server (NTRS)

Curreri, Peter A. (Editor)

1993-01-01

This document covers research results from the KC-135 Materials Science Program managed by MSFC for the period FY87 through FY89. It follows the previous NASA Technical Memorandum for FY84-86 published in August 1988. This volume contains over 30 reports grouped into eight subject areas covering acceleration levels, space flight hardware, transport and interfacial studies, thermodynamics, containerless processing, welding, melt/crucible interactions, and directional solidification. The KC-135 materials science experiments during FY87-89 accomplished direct science, preparation for space flight experiments, and justification for new experiments in orbit.

Intermittent pressure decreases human keratinocyte proliferation in vitro.

PubMed

Nasca, Maria R; Shih, Alan T; West, Dennis P; Martinez, Wanda M; Micali, Giuseppe; Landsman, Adam S

2007-01-01

The aim of this study was to investigate the correlation between pressure changes and keratinocyte proliferation by determining whether keratinocytes exposed to altered mechanical pressures would proliferate at different rates compared to control cells not subjected to pressure changes. Tissue culture flasks of human keratinocytes plated at an approximate density of 15,000 cells/cm(2) undergoing an intermittent cyclic pressure of 362 mm Hg at a frequency of 2.28 or 5.16 cycles/min (0.038 or 0.086 Hz) for 8 h were compared to control flasks grown at ambient room pressure. An in-line pressure transducer was used to monitor and adjust pressure within the cell chambers, using a solenoid valve. A thymidine incorporation assay assessed the amount of cell proliferation in each set of experiments. Differences in proliferation between keratinocytes subjected to cyclic pressure changes and control cells were found to be statistically significant (p < 0.05) in 4 out of 5 proliferation assays. Also, a higher frequency of pressure changes consistently generated a reduced proliferation rate compared to that seen in cells exposed to a lower frequency of pressure changes. These data indicate that keratinocytes undergoing intermittent pressure changes exhibit decreased proliferation rates compared to controls. Furthermore, an increased frequency rate seems to have a greater effect on proliferation than low-frequency rate pressure changes, suggesting that the stress caused by frequently changed pressure may play a greater role in reducing keratinocyte proliferation than the actual magnitude of load applied to the cells. Our results support the current treatment protocol of reducing speed and duration of walking on the site of the wound to promote healing of foot ulcers. (c) 2007 S. Karger AG, Basel.

Role of Complement C5 in Experimental Blunt Chest Trauma-Induced Septic Acute Lung Injury (ALI)

PubMed Central

Karbach, Michael; Braumueller, Sonja; Kellermann, Philipp; Gebhard, Florian; Huber-Lang, Markus; Perl, Mario

2016-01-01

Background Severe blunt chest trauma is associated with high mortality. Sepsis represents a serious risk factor for mortality in acute respiratory distress syndrome (ARDS). In septic patients with ARDS complement activation products were found to be elevated in the plasma. In single models like LPS or trauma complement has been studied to some degree, however in clinically highly relevant double hit models such as the one used here little data is available. Here, we hypothesized that absence of C5 is correlated with a decreased inflammatory response in trauma induced septic acute lung injury. Methods 12 hrs after DH in mice the local and systemic cytokines and chemokines were quantified by multiplex bead array or ELISA, activated caspase-3 by western blot. Data were analyzed using one-way ANOVA followed by post-hoc Sidak’s multiple comparison test (significance, p≤ 0.05). Results In lung tissue interleukin (IL)-6, monocyte chemo attractant protein-1 (MCP-1) and granulocyte-colony stimulating factor (G-CSF) was elevated in both C5-/- mice and wildtype littermates (wt), whereas caspase-3 was reduced in lungs after DH in C5-/- mice. Systemically, reduced keratinocyte-derived chemokine (KC) levels were observed after DH in C5-/- compared to wt mice. Locally, lung myeloperoxidase (MPO), protein, IL-6, MCP-1 and G-CSF in brochoalveolar lavage fluid (BALF) were elevated after DH in C5-/- compared to wt. Conclusions In the complex but clinically relevant DH model the local and systemic inflammatory immune response features both, C5-dependent and C5-independent characteristics. Activation of caspase-3 in lung tissue after DH was C5-dependent whereas local inflammation in lung tissue was C5-independent. PMID:27437704

Keratinocyte-driven contraction of reconstructed human skin.

PubMed

Chakrabarty, K H; Heaton, M; Dalley, A J; Dawson, R A; Freedlander, E; Khaw, P T; Mac Neil, S

2001-01-01

We have previously reported that reconstructed human skin, using deepidermized acellular sterilized dermis and allogeneic keratinocytes and fibroblasts, significantly contracts in vitro. Contracture of split skin grafts in burns injuries remains a serious problem and this in vitro model provides an opportunity to study keratinocyte/mesenchymal cell interactions and cell interactions with extracted normal human dermis. The aim of this study was to investigate the nature of this in vitro contraction and explore several approaches to prevent or reduce contraction. Three different methodologies for sterilization of the dermal matrix were examined: glycerol, ethylene oxide and a combination of glycerol and ethylene oxide. While the nature of the sterilization technique influenced the extent of contraction and thinner dermal matrices contracted proportionately more than thicker matrices, in all cases contraction was driven by the keratinocytes with relatively little influence from the fibroblasts. The contraction of the underlying dermis did not represent any change in tissue mass but rather a reorganization of the dermis which was rapidly reversed (within minutes) when the epidermal layer was removed. Pharmacological approaches to block contraction showed forskolin and mannose-6-phosphate to be ineffective and ascorbic acid-2-phosphate to exacerbate contraction. However, Galardin, a matrix metalloproteinase inhibitor and keratinocyte conditioned media, both inhibited contraction.

Differential Activation of Human Keratinocytes by Leishmania Species Causing Localized or Disseminated Disease.

PubMed

Scorza, Breanna M; Wacker, Mark A; Messingham, Kelly; Kim, Peter; Klingelhutz, Aloysius; Fairley, Janet; Wilson, Mary E

2017-10-01

All Leishmania species parasites are introduced into mammalian skin through a sand fly bite, but different species cause distinct clinical outcomes. Mouse studies suggest that early responses are critical determinants of subsequent adaptive immunity in leishmaniasis, yet few studies address the role of keratinocytes, the most abundant cell in the epidermis. We hypothesized that Leishmania infection causes keratinocytes to produce immunomodulatory factors that influence the outcome of infection. Incubation of primary or immortalized human keratinocytes with Leishmania infantum or Leishmania major, which cause visceral or cutaneous leishmaniasis, respectively, elicited dramatically different responses. Keratinocytes incubated with L. infantum significantly increased expression of proinflammatory genes for IL-6, IL-8, tumor necrosis factor, and IL-1B, whereas keratinocytes exposed to several L. major isolates did not. Furthermore, keratinocyte-monocyte co-incubation studies across a 4 µM semipermeable membrane suggested that L. infantum-exposed keratinocytes release soluble factors that enhance monocyte control of intracellular L. infantum replication (P < 0.01). L. major-exposed keratinocytes had no comparable effect. These data suggest that L. infantum and L. major differentially activate keratinocytes to release factors that limit infection in monocytes. We propose that keratinocytes initiate or withhold a proinflammatory response at the site of infection, generating a microenvironment uniquely tailored to each Leishmania species that may affect the course of disease. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

76 FR 71960 - KC Hydro LLC of New Hampshire; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-21

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 14247-000] KC Hydro LLC of..., Motions To Intervene, and Competing Applications On August 8, 2011, KC Hydro LLC of New Hampshire filed an... spillway elevation of 130 feet mean sea level (msl); (3) connecting new electrical [[Page 71961...

The protease-activated receptor 2 regulates pigmentation via keratinocyte-melanocyte interactions.

PubMed

Seiberg, M; Paine, C; Sharlow, E; Andrade-Gordon, P; Costanzo, M; Eisinger, M; Shapiro, S S

2000-01-10

Close association exists between melanocytes, the pigment melanin-producing cells in the body, and their neighboring keratinocytes. Keratinocytes are the pigment recipients and skin pigmentation is the result of this interaction. While the chemical basis of melanin production (melanogenesis) is well documented, the molecular mechanism of melanosome transfer needs to be elucidated. We are now providing first evidence that the protease-activated receptor 2 (PAR-2) expressed on keratinocytes, but not on melanocytes, is involved in melanosome transfer and therefore may regulate pigmentation. Activation of PAR-2 with trypsin or with the peptide agonist SLIGRL induced pigmentation in both two- and three-dimensional cocultures of keratinocytes and melanocytes, but not in cocultures that were spatially separated, indicating the need for intimate cell-cell contact. Topical application of SLIGRL on human skin transplanted on SCID mice resulted in a visible skin darkening. Histological examination revealed increased deposits of melanin in the keratinocytes. Inhibition of PAR-2 activation by RWJ-50353, a serine protease inhibitor, resulted in depigmentation and changes in expression of melanogenic-specific genes. Keratinocyte-melanocyte contact was essential for this depigmenting effect. Topical application of this inhibitor induced lightening of the dark skin Yucatan swine, which was confirmed by histochemical analysis. The results presented here suggest a novel mechanism for the regulation of pigmentation, mediated by the activation or inhibition of the keratinocyte receptor PAR-2. Copyright 2000 Academic Press.

Platelet-Released Growth Factors Induce Differentiation of Primary Keratinocytes

PubMed Central

Tohidnezhad, Mersedeh; Lammel, Justus; Lippross, Sebastian; Behrendt, Peter; Klüter, Tim; Pufe, Thomas; Jahr, Holger; Cremer, Jochen; Rademacher, Franziska; Gläser, Regine; Harder, Jürgen

2017-01-01

Autologous thrombocyte concentrate lysates, for example, platelet-released growth factors, (PRGFs) or their clinically related formulations (e.g., Vivostat PRF®) came recently into the physicians' focus as they revealed promising effects in regenerative and reparative medicine such as the support of healing of chronic wounds. To elucidate the underlying mechanisms, we analyzed the influence of PRGF and Vivostat PRF on human keratinocyte differentiation in vitro and on epidermal differentiation status of skin wounds in vivo. Therefore, we investigated the expression of early (keratin 1 and keratin 10) and late (transglutaminase-1 and involucrin) differentiation markers. PRGF treatment of primary human keratinocytes decreased keratin 1 and keratin 10 gene expression but induced involucrin and transglutaminase-1 gene expression in an epidermal growth factor receptor- (EGFR-) dependent manner. In concordance with these results, microscopic analyses revealed that PRGF-treated human keratinocytes displayed morphological features typical of keratinocytes undergoing terminal differentiation. In vivo treatment of artificial human wounds with Vivostat PRF revealed a significant induction of involucrin and transglutaminase-1 gene expression. Together, our results indicate that PRGF and Vivostat PRF induce terminal differentiation of primary human keratinocytes. This potential mechanism may contribute to the observed beneficial effects in the treatment of hard-to-heal wounds with autologous thrombocyte concentrate lysates in vivo. PMID:28808357

Efficient expansion of human keratinocyte stem/progenitor cells carrying a transgene with lentiviral vector

PubMed Central

2013-01-01

Introduction The development of an appropriate procedure for lentiviral gene transduction into keratinocyte stem cells is crucial for stem cell biology and regenerative medicine for genetic disorders of the skin. However, there is little information available on the efficiency of lentiviral transduction into human keratinocyte stem/progenitor cells and the effects of gene transduction procedures on growth potential of the stem cells by systematic assessment. Methods In this study, we explored the conditions for efficient expansion of human keratinocyte stem/progenitor cells carrying a transgene with a lentiviral vector, by using the culture of keratinocytes on a feeder layer of 3 T3 mouse fibroblasts. The gene transduction and expansion of keratinocytes carrying a transgene were analyzed by Western blotting, quantitative PCR, and flow cytometry. Results Polybrene (hexadiamine bromide) markedly enhanced the efficiency of lentiviral gene transduction, but negatively affected the maintenance of the keratinocyte stem/progenitor cells at a concentration higher than 5 μg/ml. Rho-assiciated kinase (ROCK) inhibitor Y-27632, a small molecule which enhanced keratinocyte proliferation, significantly interfered with the lentiviral transduction into cultured human keratinocytes. However, a suitable combination of polybrene and Y-27632 effectively expanded keratinocytes carrying a transgene. Conclusions This study provides information for effective expansion of cultured human keratinocyte stem/progenitor cells carrying a transgene. This point is particularly significant for the application of genetically modified keratinocyte stem/progenitor stem cells in regenerative medicine. PMID:24406242

Aberrant production of interleukin-8 and thrombospondin-1 by psoriatic keratinocytes mediates angiogenesis.

PubMed Central

Nickoloff, B. J.; Mitra, R. S.; Varani, J.; Dixit, V. M.; Polverini, P. J.

1994-01-01

Psoriasis is a common inherited skin disease that is characterized by hyperproliferation of epidermal keratinocytes and excessive dermal angiogenesis. A growing body of evidence supports a key pathogenetic role for activated keratinocytes in the angiogenic response that accompanies psoriasis. We investigated the role of psoriatic epidermis in the aberrant expression of angiogenesis by examining the ability of pure populations of multipassaged keratinocytes obtained from the skin of normal individuals and psoriatic patients to induce angiogenesis in vivo in the rat corneal bioassay and endothelial cell chemotaxis in vitro. Media conditioned by keratinocytes from psoriatic patients, including both symptomless skin and psoriatic plaques, induced vigorous angiogenic responses in over 90% of corneas tested and potently stimulated directional migration of capillary endothelial cells in vitro. In contrast, conditioned medium from normal keratinocyte cultures was weakly positive in less than 10% of corneas assayed and failed to stimulate endothelial cell chemotaxis. Furthermore, keratinocytes from psoriatic skin exhibited a 10- to 20-fold increase in interleukin-8 production and a seven-fold reduction in thrombospondin-1 production. The angiogenic activity present in keratinocyte-conditioned media from psoriatic patients was suppressed by adding either highly purified thrombospondin-1 (125 ng) or following the addition of either normal keratinocyte-conditioned media or neutralizing interleukin-8 antibody. We conclude that psoriatic keratinocytes are phenotypically different from normal keratinocytes with respect to their angiogenic capacity and that this aberrant phenotype is attributable to a defect in the overproduction of interleukin-8 and a deficiency in the production of the angiogenesis inhibitor thrombospondin-1. Images Figure 1 PMID:7512793

Platelet-released growth factors inhibit proliferation of primary keratinocytes in vitro.

PubMed

Bayer, Andreas; Tohidnezhad, Mersedeh; Berndt, Rouven; Lippross, Sebastian; Behrendt, Peter; Klüter, Tim; Pufe, Thomas; Jahr, Holger; Cremer, Jochen; Rademacher, Franziska; Simanski, Maren; Gläser, Regine; Harder, Jürgen

2018-01-01

Autologous thrombocyte concentrate lysates as platelet-released growth factors (PRGF) or Vivostat Platelet Rich Fibrin (PRF ® ) represent important tools in modern wound therapy, especially in the treatment of chronic, hard-to-heal or infected wounds. Nevertheless, underlying cellular and molecular mechanisms of the beneficial clinical effects of a local wound therapy with autologous thrombocyte concentrate lysates are poorly understood. Recently, we have demonstrated that PRGF induces antimicrobial peptides in primary keratinocytes and accelerates keratinocytes' differentiation. In the present study we analyzed the influence of PRGF on primary human keratinocytes' proliferation. Using the molecular proliferation marker Ki-67 we observed a concentration- and time dependent inhibition of Ki-67 gene expression in PRGF treated primary keratinocytes. These effects were independent from the EGFR- and the IL-6-R pathway. Inhibition of primary keratinocytes' proliferation by PRGF treatment was confirmed in colorimetric cell proliferation assays. Together, these data indicate that the clinically observed positive effects of autologous thrombocytes concentrates in the treatment of chronic, hard-to-heal wounds are not based on an increased keratinocytes proliferation. Copyright © 2017 Elsevier GmbH. All rights reserved.

p53-Regulated Apoptosis Is Differentiation Dependent in Ultraviolet B-Irradiated Mouse Keratinocytes

PubMed Central

Tron, Victor A.; Trotter, Martin J.; Tang, Liren; Krajewska, Maryla; Reed, John C.; Ho, Vincent C.; Li, Gang

1998-01-01

Previous studies from our laboratory, using p53 transgenic mice, have suggested that ultraviolet (UV) light-induced keratinocyte apoptosis in the skin is not affected by overexpression of mutant p53 protein. To further elucidate a possible role for p53 in UV-induced keratinocyte cell death, we now examine apoptosis in skin and isolated keratinocytes from p53 null (−/−) mice and assess the influence of cell differentiation on this process. In vivo, using this knockout model, epidermal keratinocytes in p53−/− mice exhibited only a 5.2-fold increase in apoptosis after 2000 J/m2 UVB irradiation compared with a 26.3-fold increase in normal control animals. If this p53-dependent apoptosis is important in elimination of precancerous, UV-damaged keratinocytes, then it should be active in the undifferentiated cells of the epidermal basal layer. To test this hypothesis, we examined the effect of differentiation on UV-induced apoptosis in primary cultures of murine and human keratinocytes. Apoptosis was p53-independent in undifferentiated murine keratinocytes, which exhibited relative resistance to UVB-induced killing with only a 1.5-fold increase in apoptosis in p53+/+ cells and a 1.4-fold increase in p53−/− cells. Differentiated keratinocytes, in contrast, showed a 9.4-fold UVB induction of apoptosis in p53+/+ cells, almost three times the induction observed in p53−/− cells. This UV-induced difference in apoptosis was observed when keratinocytes were cultured on type IV collagen substrate, but not on plastic alone. Western blotting of UV-irradiated, differentiated keratinocytes did not support a role for either Bax or Bcl-2 in this process. In support of these findings in mice, cell death in human cultured keratinocytes also occurred in a differentiation-associated fashion. We conclude that p53-induced apoptosis eliminates damaged keratinocytes in the differentiated cell compartment, but this mechanism is not active in the basal, undifferentiated cells and

Monocyte-derived dendritic cells exposed to Der p 1 allergen enhance the recruitment of Th2 cells: major involvement of the chemokines TARC/CCL17 and MDC/CCL22.

PubMed

Hammad, Hamida; Smits, Hermelijn H; Ratajczak, Céline; Nithiananthan, Asokananthan; Wierenga, Eddy A; Stewart, Geoffrey A; Jacquet, Alain; Tonnel, Andre-Bernard; Pestel, Joël

2003-01-01

Dendritic cells (DC) are potent antigen - presenting cells that can orientate the immune response towards a Th1 or a Th2 type. DC produce chemokines that are involved in the recruitment of either Th1 cells, such as IP10 (CXCL10), Th2 cells such as TARC (CCL17) and MDC (CCL22), or non-polarized T cells such as RANTES (CCL5) and MIP-lalpha (CCL3). We investigated whether monocyte-derived DC (MD-DC) generated from healthy donors or from patients sensitive to Dermatophagoides pteronyssinus (Dpt) and exposed to the cysteine-protease Der p 1(allergen of Dpt), could upregulate the expression of chemokines involved in type 1 or type 2 T cell recruitment. MD-DC were pulsed with either Der p 1 or with LPS as the control and the chemokines produced were evaluated using ELISA and chemotaxis assays. Der p 1-pulsed DC from allergic patients showed increased TARC (CCL17) and MDC (CCL22) production without modifying IP-10 (CXCL10) release. Der p 1-pulsed DC from healthy donors showed only increased IP-10 (CXCL10) secretion. RANTES (CCL5) and MIP-lalpha (CCL3) production were similarly increased when DC were from healthy or allergic donors. The selective Th2 clone recruitment activity of supernatants from Der p 1-pulsed DC of allergic patients was inhibited by anti-TARC (CCL17) and anti-MDC (CCL22) neutralizing Abs. By using anti-IP10 (CXCL10) blocking Abs, supernatants of Der p 1-pulsed DC from healthy donors were shown to be involved in the recruitment of Th1 cells. These results suggest that in allergic patients exposed to house dust mites, DC may favour the exacerbation of the Th2 response via the increase in type 2 chemokine production. Copyright John Libbey Eurotext 2003.

Protective effect of silk lutein on ultraviolet B-irradiated human keratinocytes.

PubMed

Pongcharoen, Sutatip; Warnnissorn, Prateep; Leŗtkajornsin, Ongart; Limpeanchob, Nanteetip; Sutheerawattananonda, Manote

2013-01-01

Carotenoids are efficient antioxidants that are of great importance for human health. Lutein and zeaxanthin are carotinoids present in high concentrations in the human retina which are involved in the photoprotection of the human eye. Lutein may also protect the skin from ultraviolet (UV)-induced damage. The present study investigated the protective effect of lutein extracted from yellow silk cocoons of Bombyx mori on human keratinocytes against UVB irradiation. A human keratinocyte cell line and primary human keratinocytes were used to investigate the UVB protection effects of silk lutein and plant lutein. Silk lutein showed no cytotoxicity to keratinocytes. Treatment with silk lutein prior to UVB irradiation enhanced cell viability and cell proliferation, and reduced cell apoptosis. The protective effects of silk lutein may be superior to those of plant lutein. Silk lutein may have a benefit for protection of keratinocytes against UVB-irradiation.

Abnormalities in the basement membrane structure promote basal keratinocytes in the epidermis of hypertrophic scars to adopt a proliferative phenotype.

PubMed

Yang, Shaowei; Sun, Yexiao; Geng, Zhijun; Ma, Kui; Sun, Xiaoyan; Fu, Xiaobing

2016-05-01

The majority of studies on scar formation have mainly focused on the dermis and little is known of the involvement of the epidermis. Previous research has demonstrated that the scar tissue-derived keratinocytes are different from normal cells at both the genetic and cell biological levels; however, the mechanisms responsible for the fundamental abnormalities in keratinocytes during scar development remain elusive. For this purpose, in this study, we used normal, wound edge and hypertrophic scar tissue to examine the morphological changes which occur during epidermal regeneration as part of the wound healing process and found that the histological structure of hypertrophic scar tissues differed from that of normal skin, with a significant increase in epidermal thickness. Notably, staining of the basement membrane (BM) appeared to be absent in the scar tissues. Moreover, immunofluorescence staining for cytokeratin (CK)10, CK14, CK5, CK19 and integrin-β1 indicated the differential expression of cell markers in the epidermal keratinocytes among the normal, wound edge and hypertrophic scar tissues, which corresponded with the altered BM structures. By using a panel of proteins associated with BM components, we validated our hypothesis that the BM plays a significant role in regulating the cell fate decision of epidermal keratinocytes during skin wound healing. Alterations in the structure of the BM promote basal keratinocytes to adopt a proliferative phenotype both in vivo and in vitro.

Anti-inflammatory effect of Schinus terebinthifolius Raddi hydroalcoholic extract on neutrophil migration in zymosan-induced arthritis.

PubMed

Rosas, Elaine Cruz; Correa, Luana Barbosa; Pádua, Tatiana de Almeida; Costa, Thadeu Estevam Moreira Maramaldo; Mazzei, José Luiz; Heringer, Alan Patrick; Bizarro, Carlos Alberto; Kaplan, Maria Auxiliadora Coelho; Figueiredo, Maria Raquel; Henriques, Maria G

2015-12-04

Schinus terebinthifolius is a species of plant from the Anacardiaceae family, which can be found in different regions of Brazil. Schinus is popularly known as aroeirinha, aroeira-vermelha, or Brazilian pepper. In folk medicine, S. terebinthifolius is used for several disorders, including inflammatory conditions, skin wounds, mucosal membrane ulcers, respiratory problems, gout, tumors, diarrhea and arthritis. According to chemical analyses, gallic acid, methyl gallate and pentagalloylglucose are the main components of hydroalcoholic extracts from S. terebinthifolius leaves. In the present study, we demonstrated the ability of a hydroalcoholic extract to inhibit cell migration in arthritis and investigated the mechanisms underlying this phenomenon. The anti-inflammatory effect of S. terebinthifolius hydroalcoholic leaf extract (ST-70) was investigated in a zymosan-induced experimental model of inflammation. Male Swiss and C57Bl/6 mice received zymosan (100 µg/cavity) via intra-thoracic (i.t.) or intra-articular (i.a.) injection after oral pre-treatment with ST-70. The direct action of ST-70 on neutrophils was evaluated via chemotaxis. ST-70 exhibited a dose-dependent effect in the pleurisy model. The median effective dose (ED50) was 100mg/kg, which inhibited 70% of neutrophil accumulation when compared with the control group. ST-70 reduced joint diameter and neutrophil influx for synovial tissues at 6h and 24h in zymosan-induced arthritis. Additionally, ST-70 inhibited synovial interleukin (IL)-6, IL-1β, keratinocyte-derived chemokine (CXCL1/KC) and Tumor Necrosis Factor (TNF)-α production at 6h and CXCL1/KC and IL-1β production at 24h. The direct activity of ST-70 on neutrophils was observed via the impairment of CXCL1/KC-induced chemotaxis in neutrophils. Oral administration of ST-70 did not induce gastric damage. Daily administration for twenty days did not kill any animals. In contrast, similar administrations of diclofenac induced gastric damage and killed

FOXO1 expression in keratinocytes promotes connective tissue healing

PubMed Central

Zhang, Chenying; Lim, Jason; Liu, Jian; Ponugoti, Bhaskar; Alsadun, Sarah; Tian, Chen; Vafa, Rameen; Graves, Dana T.

2017-01-01

Wound healing is complex and highly orchestrated. It is well appreciated that leukocytes, particularly macrophages, are essential for inducing the formation of new connective tissue, which requires the generation of signals that stimulate mesenchymal stem cells (MSC), myofibroblasts and fibroblasts. A key role for keratinocytes in this complex process has yet to be established. To this end, we investigated possible involvement of keratinocytes in connective tissue healing. By lineage-specific deletion of the forkhead box-O 1 (FOXO1) transcription factor, we demonstrate for the first time that keratinocytes regulate proliferation of fibroblasts and MSCs, formation of myofibroblasts and production of collagen matrix in wound healing. This stimulation is mediated by a FOXO1 induced TGFβ1/CTGF axis. The results provide direct evidence that epithelial cells play a key role in stimulating connective tissue healing through a FOXO1-dependent mechanism. Thus, FOXO1 and keratinocytes may be an important therapeutic target where healing is deficient or compromised by a fibrotic outcome. PMID:28220813

Chemokines and their receptors: insights from molecular modeling and crystallography.

PubMed

Kufareva, Irina

2016-10-01

Chemokines are small secreted proteins that direct cell migration in development, immunity, inflammation, and cancer. They do so by binding and activating specific G protein coupled receptors on the surface of migrating cells. Despite the importance of receptor:chemokine interactions, their structural basis remained unclear for a long time. In 2015, the first atomic resolution insights were obtained with the publication of X-ray structures for two distantly related receptors bound to chemokines. In conjunction with experiment-guided molecular modeling, the structures suggest a conserved receptor:chemokine complex architecture, while highlighting the diverse details and functional roles of individual interaction epitopes. Novel findings promote the development and detailed structural interpretation of the canonical two-site hypothesis of receptor:chemokine recognition, and suggest new avenues for pharmacological modulation of chemokine receptors. Copyright © 2016 Elsevier Ltd. All rights reserved.

Biology and clinical relevance of chemokines and chemokine receptors CXCR4 and CCR5 in human diseases

PubMed Central

Choi, Won-Tak; An, Jing

2014-01-01

Chemokines and their receptors are implicated in a wide range of human diseases, including acquired immune deficiency syndrome (AIDS). The entry of human immunodeficiency virus type 1 (HIV-1) into a cell is initiated by the interaction of the virus’s surface envelope proteins with two cell surface components of the target cell, namely CD4 and a chemokine co-receptor, usually CXCR4 or CCR5. Typical anti-HIV-1 agents include protease and reverse transcriptase inhibitors, but the targets of these agents tend to show rapid mutation rates. As such, strategies based on HIV-1 co-receptors have appeal because they target invariant host determinants. Chemokines and their receptors are also of general interest since they play important roles in numerous physiological and pathological processes in addition to AIDS. Therefore, intensive basic and translational research is ongoing for the dissection of their structure – function relationships in an effort to understand the molecular mechanism of chemokine – receptor interactions and signal transductions across cellular membranes. This paper reviews and discusses recent advances and the translation of new knowledge and discoveries into novel interventional strategies for clinical application. PMID:21565895

Astrocytes initiate inflammation in the injured mouse spinal cord by promoting the entry of neutrophils and inflammatory monocytes in an IL-1 receptor/MyD88-dependent fashion.

PubMed

Pineau, Isabelle; Sun, Libo; Bastien, Dominic; Lacroix, Steve

2010-05-01

CNS injury stimulates the expression of several proinflammatory cytokines and chemokines, some of which including MCP-1 (also known as CCL2), KC (CXCL1), and MIP-2 (CXCL2) act to recruit Gr-1(+) leukocytes at lesion sites. While earlier studies have reported that neutrophils and monocytes/macrophages contribute to secondary tissue loss after spinal cord injury (SCI), recent work has shown that depletion of Gr-1(+) leukocytes compromised tissue healing and worsened functional recovery. Here, we demonstrate that astrocytes distributed throughout the spinal cord initially contribute to early neuroinflammation by rapidly synthesizing MCP-1, KC, and MIP-2, from 3 up to 12h post-SCI. Chemokine expression by astrocytes was followed by the infiltration of blood-derived immune cells, such as type I "inflammatory" monocytes and neutrophils, into the lesion site and nearby damaged areas. Interestingly, astrocytes from mice deficient in MyD88 signaling produced significantly less MCP-1 and MIP-2 and were unable to synthesize KC. Analysis of the contribution of MyD88-dependent receptors revealed that the astrocytic expression of MCP-1, KC, and MIP-2 was mediated by the IL-1 receptor (IL-1R1), and not by TLR2 or TLR4. Flow cytometry analysis of cells recovered from the spinal cord of MyD88- and IL-1R1-knockout mice confirmed the presence of significantly fewer type I "inflammatory" monocytes and the almost complete absence of neutrophils at 12h and 4days post-SCI. Together, these results indicate that MyD88/IL-1R1 signals regulate the entry of neutrophils and, to a lesser extent, type I "inflammatory" monocytes at sites of SCI. Copyright 2009 Elsevier Inc. All rights reserved.

Anti-Inflammatory Effects of Concentrated Ethanol Extracts of Edelweiss (Leontopodium alpinum Cass.) Callus Cultures towards Human Keratinocytes and Endothelial Cells

PubMed Central

Daniela, Lulli; Alla, Potapovich; Maurelli, Riccardo; Elena, Dellambra; Giovanna, Pressi; Vladimir, Kostyuk; Roberto, Dal Toso; Chiara, De Luca; Saveria, Pastore; Liudmila, Korkina

2012-01-01

Edelweiss (Leontopodium alpinum Cass.) is traditionally employed in folk medicine as an anti-inflammatory remedy. In nature, the plant is sparsely available and protected; therefore production of callus cultures was established. A concentrated ethanolic extract of culture homogenate, with leontopodic acid representing 55 ± 2% of the total phenolic fraction (ECC55), was characterized for anti-inflammatory properties in primary human keratinocytes (PHKs) and endotheliocytes (HUVECs). Inflammatory responses were induced by UVA+UVB, lipopolysaccharide (LPS), oxidized low-density lipoprotein (oxLDL), and a mixture of proinflammatory cytokines. Trichostatin A, a sirtuin inhibitor, was used to induce keratinocyte inflammatory senescence. ECC55 (10–50 μg/mL) protected PHK from solar UV-driven damage, by enhancing early intracellular levels of nitric oxide, although not affecting UV-induced expression of inflammatory genes. Comparison of the dose-dependent inhibition of chemokine (IL-8, IP-10, MCP-1) and growth factor (GM-CSF) release from PHK activated by TNFα + IFNγ showed that leontopodic acid was mainly responsible for the inhibitory effects of ECC55. Sirtuin-inhibited cell cycle, proliferation, and apoptosis markers were restored by ECC55. The extract inhibited LPS-induced IL-6 and VCAM1 genes in HUVEC, as well as oxLDL-induced selective VCAM1 overexpression. Conclusion. Edelweiss cell cultures could be a valuable source of anti-inflammatory substances potentially applicable for chronic inflammatory skin diseases and bacterial and atherogenic inflammation. PMID:23093820

Polarizability of KC60: Evidence for Potassium Skating on the C60 Surface

NASA Astrophysics Data System (ADS)

Rayane, D.; Antoine, R.; Dugourd, Ph.; Benichou, E.; Allouche, A. R.; Aubert-Frécon, M.; Broyer, M.

2000-02-01

We present the first measurement of the polarizability and the permanent dipole moment of isolated KC60 molecules by molecular beam deflection technique. We have obtained a value of 2506+/-250 Å3 for the polarizability at room temperature. The addition of a potassium atom enhances by more than a factor of 20 the polarizability of a pure C60 molecule. This very high polarizability and the lack of observed permanent dipole show that the apparent polarizability of KC60 is induced by the free skating of the potassium atom on the C60 surface, resulting in a statistical orientation of the dipole. The results are interpreted with a simple model similar to the Langevin theory for paramagnetic systems.

Inflammatory role and prognostic value of platelet chemokines in acute coronary syndrome.

PubMed

Blanchet, X; Cesarek, K; Brandt, J; Herwald, H; Teupser, D; Küchenhoff, H; Karshovska, E; Mause, S F; Siess, W; Wasmuth, H; Soehnlein, O; Koenen, R R; Weber, C; von Hundelshausen, P

2014-12-01

Activated platelets and neutrophils exacerbate atherosclerosis. Platelets release the chemokines CXCL4, CXCL4L1 and CCL5, whereas myeloperoxidase (MPO) and azurocidin are neutrophil-derived. We investigated whether plasma levels of these platelet and neutrophil mediators are affected by the acute coronary syndrome (ACS), its medical treatment, concomitant clinical or laboratory parameters, and predictive for the progression of coronary artery disease (CAD). In an observational study, the association of various factors with plasma concentrations of platelet chemokines and neutrophil mediators in 204 patients, either upon admission with ACS and 6 hours later or without ACS or CAD, was determined by multiple linear regression. Mediator release was further analysed after activation of blood with ACS-associated triggers such as plaque material. CXCL4, CXCL4L1, CCL5, MPO and azurocidin levels were elevated in ACS. CXCL4 and CCL5 but not CXCL4L1 or MPO were associated with platelet counts and CRP. CXCL4 (in association with heparin treatment) and MPO declined over 6 hours during ACS. Elevated CCL5 was associated with a progression of CAD. Incubating blood with plaque material, PAR1 and PAR4 activation induced a marked release of CXCL4 and CCL5, whereas CXCL4L1 and MPO were hardly or not altered. Platelet chemokines and neutrophil products are concomitantly elevated in ACS and differentially modulated by heparin treatment. CCL5 levels during ACS predict a progression of preexisting CAD. Platelet-derived products appear to dominate the inflammatory response during ACS, adding to the emerging evidence that ACS per se may promote vascular inflammation.

Defective chemokine signal integration in leukocytes lacking activator of G protein signaling 3 (AGS3).

PubMed

Branham-O'Connor, Melissa; Robichaux, William G; Zhang, Xian-Kui; Cho, Hyeseon; Kehrl, John H; Lanier, Stephen M; Blumer, Joe B

2014-04-11

Activator of G-protein signaling 3 (AGS3, gene name G-protein signaling modulator-1, Gpsm1), an accessory protein for G-protein signaling, has functional roles in the kidney and CNS. Here we show that AGS3 is expressed in spleen, thymus, and bone marrow-derived dendritic cells, and is up-regulated upon leukocyte activation. We explored the role of AGS3 in immune cell function by characterizing chemokine receptor signaling in leukocytes from mice lacking AGS3. No obvious differences in lymphocyte subsets were observed. Interestingly, however, AGS3-null B and T lymphocytes and bone marrow-derived dendritic cells exhibited significant chemotactic defects as well as reductions in chemokine-stimulated calcium mobilization and altered ERK and Akt activation. These studies indicate a role for AGS3 in the regulation of G-protein signaling in the immune system, providing unexpected venues for the potential development of therapeutic agents that modulate immune function by targeting these regulatory mechanisms.

Effect of Wnt3a on Keratinocytes Utilizing in Vitro and Bioinformatics Analysis

PubMed Central

Nam, Ju-Suk; Chakraborty, Chiranjib; Sharma, Ashish Ranjan; Her, Young; Bae, Kee-Jeong; Sharma, Garima; Doss, George Priya; Lee, Sang-Soo; Hong, Myung-Sun; Song, Dong-Keun

2014-01-01

Wingless-type (Wnt) signaling proteins participate in various cell developmental processes. A suppressive role of Wnt5a on keratinocyte growth has already been observed. However, the role of other Wnt proteins in proliferation and differentiation of keratinocytes remains unknown. Here, we investigated the effects of the Wnt ligand, Wnt3a, on proliferation and differentiation of keratinocytes. Keratinocytes from normal human skin were cultured and treated with recombinant Wnt3a alone or in combination with the inflammatory cytokine, tumor necrosis factor α (TNFα). Furthermore, using bioinformatics, we analyzed the biochemical parameters, molecular evolution, and protein–protein interaction network for the Wnt family. Application of recombinant Wnt3a showed an anti-proliferative effect on keratinocytes in a dose-dependent manner. After treatment with TNFα, Wnt3a still demonstrated an anti-proliferative effect on human keratinocytes. Exogenous treatment of Wnt3a was unable to alter mRNA expression of differentiation markers of keratinocytes, whereas an altered expression was observed in TNFα-stimulated keratinocytes. In silico phylogenetic, biochemical, and protein–protein interaction analysis showed several close relationships among the family members of the Wnt family. Moreover, a close phylogenetic and biochemical similarity was observed between Wnt3a and Wnt5a. Finally, we proposed a hypothetical mechanism to illustrate how the Wnt3a protein may inhibit the process of proliferation in keratinocytes, which would be useful for future researchers. PMID:24686518

Autologous cultured keratinocytes on porcine gelatin microbeads effectively heal chronic venous leg ulcers.

PubMed

Liu, Jin Yu; Hafner, Jürg; Dragieva, Galya; Seifert, Burkhardt; Burg, Günter

2004-01-01

We have established a specific bioreactor microcarrier cell culture system using porcine gelatin microbeads as carriers to produce autologous keratinocytes on a large scale. Moreover, we have shown that autologous keratinocytes can be cultured on porcine collagen pads, thereby forming a single cell layer. The objective of this study was to compare efficacy and safety of autologous cultured keratinocytes on microbeads and collagen pads in the treatment of chronic wounds. Fifteen patients with recalcitrant venous leg ulcers were assigned to three groups in a single-center, prospective, uncontrolled study: five underwent a single treatment with keratinocyte monolayers on collagen pads (group 1); another five received a single grafting with keratinocyte-microbeads (group 2); and the last five received multiple, consecutive applications of keratinocyte-microbeads 3 days apart (group 3). All patients were followed for up to 12 weeks. By 12 weeks, there was a mean reduction in the initial wound area of 50, 83, and 97 percent in the three groups, respectively. The changes in wound size were statistically significant between the first and third groups (p= 0.0003). Keratinocyte-microbeads proved to be more effective than keratinocyte monolayers on collagen pads when the former were applied every 3 days. Rapid availability within 10-13 days after skin biopsy and easy handling represent particular advantages.

Elevated expression of CXC chemokines in pediatric osteosarcoma patients.

PubMed

Li, Yiting; Flores, Ricardo; Yu, Alexander; Okcu, M Fatih; Murray, Jeffrey; Chintagumpala, Murali; Hicks, John; Lau, Ching C; Man, Tsz-Kwong

2011-01-01

Osteosarcoma is the most common malignant bone tumor in children. Despite the advent of chemotherapy, the survival of osteosarcoma patients has not been significantly improved recently. Chemokines are a group of signaling molecules that have been implicated in tumorigenesis and metastasis. The authors used an antibody microarray to identify chemokines that were elevated in the plasma samples of osteosarcoma patients. The results were validated using enzyme-linked immunosorbent assays on an independent set of samples. The tumor expressions of 3 chemokines were examined in 2 sets of osteosarcoma tissue arrays. The authors also evaluated the proliferative effect of the chemokines in 4 osteosarcoma cell lines. The authors found that the plasma levels of CXCL4, CXCL6, and CXCL12 in the osteosarcoma patients were significantly higher than those in the controls, and the results were validated by an independent osteosarcoma cohort (P < .05). However, CXCL4 (100%) and CXCL6 (91%) were frequently expressed in osteosarcoma, whereas CXCL12 was only expressed in 4%. Survival analysis further showed that higher circulating levels of CXCL4 and CXCL6, but not CXCL12, were associated with a poorer outcome of osteosarcoma patients. Addition of exogenous chemokines significantly promoted the growth of different osteosarcoma cells (P < .05). The results demonstrate that CXCL4 and CXCL6 are frequently expressed in osteosarcoma, and that the plasma levels of these 2 chemokines are associated with patient outcomes. Further study of these circulating chemokines may provide a promising approach for prognostication of osteosarcoma. Targeting these chemokines or their receptors may also lead to a novel therapeutic invention. © 2010 American Cancer Society.

p53 and TAp63 Promote Keratinocyte Proliferation and Differentiation in Breeding Tubercles of the Zebrafish

PubMed Central

Fischer, Boris; Metzger, Manuel; Richardson, Rebecca; Knyphausen, Philipp; Ramezani, Thomas; Franzen, Rainer; Schmelzer, Elmon; Bloch, Wilhelm; Carney, Thomas J.; Hammerschmidt, Matthias

2014-01-01

p63 is a multi-isoform member of the p53 family of transcription factors. There is compelling genetic evidence that ΔNp63 isoforms are needed for keratinocyte proliferation and stemness in the developing vertebrate epidermis. However, the role of TAp63 isoforms is not fully understood, and TAp63 knockout mice display normal epidermal development. Here, we show that zebrafish mutants specifically lacking TAp63 isoforms, or p53, display compromised development of breeding tubercles, epidermal appendages which according to our analyses display more advanced stratification and keratinization than regular epidermis, including continuous desquamation and renewal of superficial cells by derivatives of basal keratinocytes. Defects are further enhanced in TAp63/p53 double mutants, pointing to partially redundant roles of the two related factors. Molecular analyses, treatments with chemical inhibitors and epistasis studies further reveal the existence of a linear TAp63/p53->Notch->caspase 3 pathway required both for enhanced proliferation of keratinocytes at the base of the tubercles and their subsequent differentiation in upper layers. Together, these studies identify the zebrafish breeding tubercles as specific epidermal structures sharing crucial features with the cornified mammalian epidermis. In addition, they unravel essential roles of TAp63 and p53 to promote both keratinocyte proliferation and their terminal differentiation by promoting Notch signalling and caspase 3 activity, ensuring formation and proper homeostasis of this self-renewing stratified epithelium. PMID:24415949

Enhanced expression of IL-8 in normal human keratinocytes and human keratinocyte cell line HaCaT in vitro after stimulation with contact sensitizers, tolerogens and irritants.

PubMed

Mohamadzadeh, M; Müller, M; Hultsch, T; Enk, A; Saloga, J; Knop, J

1994-12-01

To investigate the interleukin-8 production of keratinocytes after stimulation in vitro we have used various agents: (i) contact sensitizer (2,4-dinitrofluorobenzene, 3-n-pentadecylcatechol); (ii) tolerogen (5-methyl-3-n-pentadecylcatechol); (iii) irritant (sodium lauryl sulfate). Interleukin-8 gene expression was assessed by northern blot hybridization of the total cytoplasmic RNA extracted from subconfluent normal human keratinocyte cultures and the keratinocyte cell line HaCaT using a radiolabeled DNA probe specific for human interleukin-8. Interleukin-8 gene expression was markedly increased upon in vitro stimulation after 1-6 h with contact sensitizers, tolerogen and the irritant. In contrast, interleukin-8 production was not detectable in unstimulated normal human keratinocytes or the HaCaT keratinocyte cell line. These results suggest that the induction and production of interleukin-8 is a response to nonspecific stimuli and may play a critical role in the early response to immunogenic or inflammatory signals in man.

Stem/progenitor cell-like properties of desmoglein 3dim cells in primary and immortalized keratinocyte lines.

PubMed

Wan, Hong; Yuan, Ming; Simpson, Cathy; Allen, Kirsty; Gavins, Felicity N E; Ikram, Mohammed S; Basu, Subham; Baksh, Nuzhat; O'Toole, Edel A; Hart, Ian R

2007-05-01

We showed previously that primary keratinocytes selected for low desmoglein 3 (Dsg3) expression levels exhibited increased colony-forming efficiency and heightened proliferative potential relative to cells with higher Dsg3 expression levels, characteristics consistent with a more "stem/progenitor cell-like" phenotype. Here, we have confirmed that Dsg3(dim) cells derived from cultured primary human adult keratinocytes have comparability with alpha(6)(bri)/CD71(dim) stem cells in terms of colony-forming efficiency. Moreover, these Dsg3(dim) cells exhibit increased reconstituting ability in in vitro organotypic culture on de-epidermalized dermis (DED); they are small, actively cycling cells, and they express elevated levels of various p63 isoforms. In parallel, using the two immortalized keratinocyte cell lines HaCaT and NTERT, we obtained essentially similar though occasionally different findings. Thus, reduced colony-forming efficiency by Dsg3(bri) cells consistently was observed in both cell lines even though the cell cycle profile and levels of p63 isoforms in the bri and dim populations differed between these two cell lines. Dsg3(dim) cells from both immortalized lines produced thicker and better ordered hierarchical structural organization of reconstituted epidermis relative to Dsg3(bri) and sorted control cells. Dsg3(dim) HaCaT cells also show sebocyte-like differentiation in the basal compartment of skin reconstituted after a 4-week organotypic culture. No differences in percentages of side population cells (also a putative marker of stem cells) were detected between Dsg3(dim) and Dsg3(bri) populations. Taken together our data indicate that Dsg3(dim) populations from primary human adult keratinocytes and long-term established keratinocyte lines possess certain stem/progenitor cell-like properties, although the side population characteristic is not one of these features. Disclosure of potential conflicts of interest is found at the end of this article.

Air Force Air Refueling: The KC-X Aircraft Acquisition Program

DTIC Science & Technology

2008-04-04

13 National Military Strategy (NMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Mobility Capability Study...condition and sustainment costs of the KC-135” ... and that “an early replacement program would be a hedging strategy against that uncertainty.”40...the President’s overall national security strategy . Based on the President’s strategy , DOD periodically studies the global threat environment and

Macelignan inhibits melanosome transfer mediated by protease-activated receptor-2 in keratinocytes.

PubMed

Choi, Eun-Jung; Kang, Young-Gyu; Kim, Jaekyung; Hwang, Jae-Kwan

2011-01-01

Skin pigmentation is the result of melanosome transfer from melanocytes to keratinocytes. Protease-activated receptor-2 (PAR-2) is a key mediator of melanosome transfer, which occurs as the melanocyte extends its dendrite toward surrounding keratinocytes that take up melanosomes by phagocytosis. We investigated the effects of macelignan isolated from Myristica fragrans HOUTT. (nutmeg) on melanosome transfer and the regulation of PAR-2 in human keratinocytes (HaCaT). HaCaT cells stimulated by the PAR-2-activating peptide Ser-Leu-Ile-Gly-Arg-Leu-NH₂ (SLIGRL) were treated with macelignan; PAR-2 expression was then determined by reverse transcription-polymerase chain reaction (RT-PCR), Western blot, and immunocytochemistry. We evaluated the effects of macelignan on calcium mobilization and keratinocyte phagocytosis. In addition, B16F10 melanoma cells and keratinocytes were co-cultured to assess the effects of macelignan on prostaglandin E₂ (PGE₂) secretion and subsequent dendrite formation. Macelignan decreased HaCaT PAR-2 mRNA and protein levels in a dose-dependent manner. Furthermore, macelignan markedly reduced intracellular calcium mobilization and significantly downregulated keratinocyte phagocytosis, as shown by decreased ingestion of Escherichia coli bioparticles and fluorescent microspheres. In co-culture experiments, macelignan reduced keratinocyte PGE₂ secretion, thereby preventing dendrite formation in B16F10 melanoma cells compared with SLIGRL-treated controls. Macelignan inhibits melanosome transfer by downregulating PAR-2, thereby reducing keratinocyte phagocytosis and PGE₂ secretion, which in turn inhibits dendrite formation in B16F10 melanoma cells. Taken together, our findings suggest that macelignan could be used as a natural depigmenting agent to ameliorate hyperpigmentation.

Alternative C-Terminal Helix Orientation Alters Chemokine Function

PubMed Central

Kuo, Je-Hung; Chen, Ya-Ping; Liu, Jai-Shin; Dubrac, Alexandre; Quemener, Cathy; Prats, Hervé; Bikfalvi, Andreas; Wu, Wen-guey; Sue, Shih-Che

2013-01-01

Chemokines, a subfamily of cytokines, are small, secreted proteins that mediate a variety of biological processes. Various chemokines adopt remarkable conserved tertiary structure comprising an anti-parallel β-sheet core domain followed by a C-terminal helix that packs onto the β-sheet. The conserved structural feature has been considered critical for chemokine function, including binding to cell surface receptor. The recently isolated variant, CXCL4L1, is a homologue of CXCL4 chemokine (or platelet factor 4) with potent anti-angiogenic activity and differed only in three amino acid residues of P58L, K66E, and L67H. In this study we show by x-ray structural determination that CXCL4L1 adopts a previously unrecognized structure at its C terminus. The orientation of the C-terminal helix protrudes into the aqueous space to expose the entire helix. The alternative helix orientation modifies the overall chemokine shape and surface properties. The L67H mutation is mainly responsible for the swing-out effect of the helix, whereas mutations of P58L and K66E only act secondarily. This is the first observation that reports an open conformation of the C-terminal helix in a chemokine. This change leads to a decrease of its glycosaminoglycan binding properties and to an enhancement of its anti-angiogenic and anti-tumor effects. This unique structure is recent in evolution and has allowed CXCL4L1 to gain novel functional properties. PMID:23536183

Impact of periodontitis on chemokines in smokers.

PubMed

Haytural, O; Yaman, D; Ural, E C; Kantarci, A; Demirel, Korkud

2015-06-01

The aim of this study was to investigate the chemokine expression profiles in gingival crevicular fluid (GCF) and serum in patients with advanced chronic periodontitis and to assess the impact of smoking on local and systemic levels of chemokines. Thirty patients with chronic periodontitis (CP; 20 smokers and 10 non-smokers) and 20 periodontally healthy subjects (10 smokers and 10 non-smokers) were recruited. Clinical parameters included the plaque index (PI), gingival index (GI), and bleeding on probing (BOP). Macrophage inflammatory protein-1 alpha (MIP-1α), macrophage inflammatory protein-1 beta (MIP-1β), monocyte chemoattractant protein-1 (MCP-1), and regulated on activation normal T cell expressed and secreted chemokine (RANTES) were measured in gingival crevicular fluid (GCF) and serum using a multiplex immunoassay. MIP-1α levels were significantly lower (10.15 ± 1.48; p = 0.039) while MIP-1β levels were significantly higher (42.05 ± 8.21; p = 0.005) in sera from non-smoker patients with CP compared to non-smoker healthy subjects. MCP-1 concentration in sera was significantly higher in smoker periodontitis patients (8.89 ± 1.65) compared to non-smoker patients with periodontitis (8.14 ± 0.97; p = 0.004). MIP-1α and RANTES were significantly higher in GCF of the patients with CP (p = 0.001) while there were no statistically significant correlations between the GCF levels of these analytes and the smoking status. Periodontal inflammation increases the chemokine concentrations in the GCF while smoking suppresses chemokine levels in serum suggesting that different local and systemic mechanisms are involved during the response to periodontitis in smokers. Understanding the local and systemic chemokine responses in smokers will enable the development of biologically-based treatment methods for chronic periodontitis.

Keratinocytes propagated in serum-free, feeder-free culture conditions fail to form stratified epidermis in a reconstituted skin model.

PubMed

Lamb, Rebecca; Ambler, Carrie A

2013-01-01

Primary human epidermal stem cells isolated from skin tissues and subsequently expanded in tissue culture are used for human therapeutic use to reconstitute skin on patients and to generate artificial skin in culture for academic and commercial research. Classically, epidermal cells, known as keratinocytes, required fibroblast feeder support and serum-containing media for serial propagation. In alignment with global efforts to remove potential animal contaminants, many serum-free, feeder-free culture methods have been developed that support derivation and growth of these cells in 2-dimensional culture. Here we show that keratinocytes grown continually in serum-free and feeder-free conditions were unable to form into a stratified, mature epidermis in a skin equivalent model. This is not due to loss of cell potential as keratinocytes propagated in serum-free, feeder-free conditions retain their ability to form stratified epidermis when re-introduced to classic serum-containing media. Extracellular calcium supplementation failed to improve epidermis development. In contrast, the addition of serum to commercial, growth media developed for serum-free expansion of keratinocytes facilitated 3-dimensional stratification in our skin equivalent model. Moreover, the addition of heat-inactivated serum improved the epidermis structure and thickness, suggesting that serum contains factors that both aid and inhibit stratification.

Keratinocytes Propagated in Serum-Free, Feeder-Free Culture Conditions Fail to Form Stratified Epidermis in a Reconstituted Skin Model

PubMed Central

Lamb, Rebecca; Ambler, Carrie A.

2013-01-01

Primary human epidermal stem cells isolated from skin tissues and subsequently expanded in tissue culture are used for human therapeutic use to reconstitute skin on patients and to generate artificial skin in culture for academic and commercial research. Classically, epidermal cells, known as keratinocytes, required fibroblast feeder support and serum-containing media for serial propagation. In alignment with global efforts to remove potential animal contaminants, many serum-free, feeder-free culture methods have been developed that support derivation and growth of these cells in 2-dimensional culture. Here we show that keratinocytes grown continually in serum-free and feeder-free conditions were unable to form into a stratified, mature epidermis in a skin equivalent model. This is not due to loss of cell potential as keratinocytes propagated in serum-free, feeder-free conditions retain their ability to form stratified epidermis when re-introduced to classic serum-containing media. Extracellular calcium supplementation failed to improve epidermis development. In contrast, the addition of serum to commercial, growth media developed for serum-free expansion of keratinocytes facilitated 3-dimensional stratification in our skin equivalent model. Moreover, the addition of heat-inactivated serum improved the epidermis structure and thickness, suggesting that serum contains factors that both aid and inhibit stratification. PMID:23326335

Filaggrin-dependent secretion of sphingomyelinase protects against staphylococcal α-toxin-induced keratinocyte death.

PubMed

Brauweiler, Anne M; Bin, Lianghua; Kim, Byung Eui; Oyoshi, Michiko K; Geha, Raif S; Goleva, Elena; Leung, Donald Y M

2013-02-01

The skin of patients with atopic dermatitis (AD) has defects in keratinocyte differentiation, particularly in expression of the epidermal barrier protein filaggrin. AD skin lesions are often exacerbated by Staphylococcus aureus-mediated secretion of the virulence factor α-toxin. It is unknown whether lack of keratinocyte differentiation predisposes to enhanced lethality from staphylococcal toxins. We investigated whether keratinocyte differentiation and filaggrin expression protect against cell death induced by staphylococcal α-toxin. Filaggrin-deficient primary keratinocytes were generated through small interfering RNA gene knockdown. RNA expression was determined by using real-time PCR. Cell death was determined by using the lactate dehydrogenase assay. Keratinocyte cell survival in filaggrin-deficient (ft/ft) mouse skin biopsies was determined based on Keratin 5 staining. α-Toxin heptamer formation and acid sphingomyelinase expression were determined by means of immunoblotting. We found that filaggrin expression, occurring as the result of keratinocyte differentiation, significantly inhibits staphylococcal α-toxin-mediated pathogenicity. Furthermore, filaggrin plays a crucial role in protecting cells by mediating the secretion of sphingomyelinase, an enzyme that reduces the number of α-toxin binding sites on the keratinocyte surface. Finally, we determined that sphingomyelinase enzymatic activity directly prevents α-toxin binding and protects keratinocytes against α-toxin-induced cytotoxicity. The current study introduces the novel concept that S aureus α-toxin preferentially targets and destroys filaggrin-deficient keratinocytes. It also provides a mechanism to explain the increased propensity for S aureus-mediated exacerbation of AD skin disease. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Dual-Color Luciferase Complementation for Chemokine Receptor Signaling.

PubMed

Luker, Kathryn E; Luker, Gary D

2016-01-01

Chemokine receptors may share common ligands, setting up potential competition for ligand binding, and association of activated receptors with downstream signaling molecules such as β-arrestin. Determining the "winner" of competition for shared effector molecules is essential for understanding integrated functions of chemokine receptor signaling in normal physiology, disease, and response to therapy. We describe a dual-color click beetle luciferase complementation assay for cell-based analysis of interactions of two different chemokine receptors, CXCR4 and ACKR3, with the intracellular scaffolding protein β-arrestin 2. This assay provides real-time quantification of receptor activation and signaling in response to chemokine CXCL12. More broadly, this general imaging strategy can be applied to quantify interactions of any set of two proteins that interact with a common binding partner. © 2016 Elsevier Inc. All rights reserved.

STS-42 Payload Specialist Merbold inside KC-135 during zero gravity flight

NASA Image and Video Library

1988-05-24

S88-37966 (2 Oct 1988) --- European Space Agency payload specialists Ulf Merbold (STS-42, right) and Reinhold Furrer (STS 61-A) get the "feel" of zero-gravity aboard NASA's KC-135 aircraft over the Gulf of Mexico.

The CXCR4/SDF-1 chemokine receptor axis: a new target therapeutic for non-small cell lung cancer.

PubMed

Otsuka, Shannon; Bebb, Gwyn

2008-12-01

Chemokines are proinflammatory chemoattractant cytokines that regulate cell trafficking and adhesion. The CXCR4 chemokine receptor and its ligand, stromal cell derived factor (SDF-1), constitute a chemokine/receptor axis that has attracted great interest because of an increasing understanding of its role in cancer, including lung cancer. The CXCR4/SDF-1 complex activates several pathways that mediate chemotaxis, migration and secretion of angiopoietic factors. Neutralization of SDF-1 by anti-SDF-1 or anti-CXCR4 monoclonal antibody in preclinical in vivo studies results in a significant decrease of non-small cell lung cancer metastases. Since anti-SDF-1/CXCR4 strategies have already been developed for use in combating human immunodeficiency virus infections, it is likely that these approaches will be used in clinical trials in non-small cell lung cancer in the very near future.

Volatile Removal Assembly Flight Experiment and KC-135 Packed Bed Experiment: Results and Lessons Learned

NASA Technical Reports Server (NTRS)

Holder, Donald W.; Parker, David

2000-01-01

The Volatile Removal Assembly (VRA) is a high temperature catalytic oxidation process that will be used as the final treatment for recycled water aboard the International Space Station (ISS). The multiphase nature of the process had raised concerns as to the performance of the VRA in a microgravity environment. To address these concerns, two experiments were designed. The VRA Flight Experiment (VRAFE) was designed to test a full size VRA under controlled conditions in microgravity aboard the SPACEHAB module and in a 1 -g environment and compare the performance results. The second experiment relied on visualization of two-phase flow through small column packed beds and was designed to fly aboard NASA's microgravity test bed plane (KC-135). The objective of the KC-135 experiment was to understand the two-phase fluid flow distribution in a packed bed in microgravity. On Space Transportation System (STS) flight 96 (May 1999), the VRA FE was successfully operated and in June 1999 the KC-135 packed bed testing was completed. This paper provides an overview of the experiments and a summary of the results and findings.

Lyophilized keratinocyte cell lysates contain multiple mitogenic activities and stimulate closure of meshed skin autograft-covered burn wounds with efficiency similar to that of fresh allogeneic keratinocyte cultures.

PubMed

Duinslaeger, L; Verbeken, G; Reper, P; Delaey, B; Vanhalle, S; Vanderkelen, A

1996-07-01

For several years, grafting with allogeneic keratinocyte cultures has been used successfully as a wound-healing therapy both by us and by many other groups. Since their postgrafting survival time is limited, the effect of these cultures is generally explained by the production of wound repair-stimulating factors that promote proliferation and migration of resident cells. In this study we show that lysates of cultured keratinocytes contain mitogenic activity for keratinocytes, endothelial cells, and fibroblasts. In addition, the lysates inhibit the contraction of collagen gels by human skin fibroblasts. On the basis of these observations and of in vivo data obtained by ourselves and others, we have evaluated the effect of total keratinocyte lysates on the healing of meshed skin autograft-covered burn wounds. Twenty burn wounds were tangentially excised and autografted with one to three meshed conventional skin transplants. An area treated with a gel containing lysated keratinocyte cultures was compared with an area treated with placebo-gel in terms of epithelialization on day 5. In six patients an additional fresh keratinocyte alloculture was applied as a positive control. Results indicate that the newly formed epithelium (difference between percentage of epithelialization on day 5 and on day 0) was 31.1 percent in the treated area compared with 16.5 percent in the placebo area. This result is comparable with the value obtained by treatment with fresh keratinocyte allocultures, namely, 33.8 percent. These figures show a twofold stimulation of epithelialization.

Saponins from Tribulus terrestris L. protect human keratinocytes from UVB-induced damage.

PubMed

Sisto, Margherita; Lisi, Sabrina; D'Amore, Massimo; De Lucro, Raffaella; Carati, Davide; Castellana, Donatello; La Pesa, Velia; Zuccarello, Vincenzo; Lofrumento, Dario D

2012-12-05

Chronic exposure to solar UVB radiation damages skin, increasing the risk to develop cancer. Hence the identification of compounds with a photoprotective efficacy is essential. This study examined the role of saponins derived from Tribulus terrestris L. (TT) on the modulation of apoptosis in normal human keratinocytes (NHEK) exposed to physiological doses of UVB and to evaluate their antitumoral properties. In NHEK, TT saponins attenuate UVB-induced programmed cell death through inhibition of intrinsic apoptotic pathway. In squamous cell carcinomas (SCC) TT saponins do not make the malignant keratinocytes more resistant to UVB and determine an enhanced apoptotic response. The photoprotective effect of TT saponins is tightly correlated to the enhancement of NER genes expression and the block of UVB-mediated NF-κB activation. Collectively, our study shows experimental evidence that TT has a preventive efficacy against UVB-induced carcinogenesis and the molecular knowledge on the mechanisms through which TT saponins regulate cell death suggests great potential for TT to be developed into a new medicine for cancer patients. Copyright © 2012 Elsevier B.V. All rights reserved.

Abnormalities in the basement membrane structure promote basal keratinocytes in the epidermis of hypertrophic scars to adopt a proliferative phenotype

PubMed Central

YANG, SHAOWEI; SUN, YEXIAO; GENG, ZHIJUN; MA, KUI; SUN, XIAOYAN; FU, XIAOBING

2016-01-01

The majority of studies on scar formation have mainly focused on the dermis and little is known of the involvement of the epidermis. Previous research has demonstrated that the scar tissue-derived keratinocytes are different from normal cells at both the genetic and cell biological levels; however, the mechanisms responsible for the fundamental abnormalities in keratinocytes during scar development remain elusive. For this purpose, in this study, we used normal, wound edge and hypertrophic scar tissue to examine the morphological changes which occur during epidermal regeneration as part of the wound healing process and found that the histological structure of hypertrophic scar tissues differed from that of normal skin, with a significant increase in epidermal thickness. Notably, staining of the basement membrane (BM) appeared to be absent in the scar tissues. Moreover, immunofluorescence staining for cytokeratin (CK)10, CK14, CK5, CK19 and integrin-β1 indicated the differential expression of cell markers in the epidermal keratinocytes among the normal, wound edge and hypertrophic scar tissues, which corresponded with the altered BM structures. By using a panel of proteins associated with BM components, we validated our hypothesis that the BM plays a significant role in regulating the cell fate decision of epidermal keratinocytes during skin wound healing. Alterations in the structure of the BM promote basal keratinocytes to adopt a proliferative phenotype both in vivo and in vitro. PMID:26986690

Dual GPCR and GAG mimicry by the M3 chemokine decoy receptor

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

Alexander-Brett, Jennifer M.; Fremont, Daved H.

2008-09-23

Viruses have evolved a myriad of evasion strategies focused on undermining chemokine-mediated immune surveillance, exemplified by the mouse {gamma}-herpesvirus 68 M3 decoy receptor. Crystal structures of M3 in complex with C chemokine ligand 1/lymphotactin and CC chemokine ligand 2/monocyte chemoattractant protein 1 reveal that invariant chemokine features associated with G protein-coupled receptor binding are primarily recognized by the decoy C-terminal domain, whereas the N-terminal domain (NTD) reconfigures to engage divergent basic residue clusters on the surface of chemokines. Favorable electrostatic forces dramatically enhance the association kinetics of chemokine binding by M3, with a primary role ascribed to acidic NTD regionsmore » that effectively mimic glycosaminoglycan interactions. Thus, M3 employs two distinct mechanisms of chemical imitation to potently sequester chemokines, thereby inhibiting chemokine receptor binding events as well as the formation of chemotactic gradients necessary for directed leukocyte trafficking.« less

Hyaluronan Does Not Regulate Human Epidermal Keratinocyte Proliferation and Differentiation*

PubMed Central

Malaisse, Jérémy; Pendaries, Valérie; Hontoir, Fanny; De Glas, Valérie; Van Vlaender, Daniel; Simon, Michel; Lambert de Rouvroit, Catherine; Poumay, Yves; Flamion, Bruno

2016-01-01

Hyaluronan (HA) is synthesized by three HA synthases (HAS1, HAS2, and HAS3) and secreted in the extracellular matrix. In human skin, large amounts of HA are found in the dermis. HA is also synthesized by keratinocytes in the epidermis, although its epidermal functions are not clearly identified yet. To investigate HA functions, we studied the effects of HA depletion on human keratinocyte physiology within in vitro reconstructed human epidermis. Inhibition of HA synthesis with 4-methylumbelliferone (4MU) did not modify the expression profile of the epidermal differentiation markers involucrin, keratin 10, and filaggrin during tissue reconstruction. In contrast, when keratinocytes were incubated with 4MU, cell proliferation was decreased. In an attempt to rescue the proliferation function, HA samples of various mean molecular masses were added to keratinocyte cultures treated with 4MU. These samples were unable to rescue the initial proliferation rate. Furthermore, treatments with HA-specific hyaluronidase, although removing almost all HA from keratinocyte cultures, did not alter the differentiation or proliferation processes. The differences between 4MU and hyaluronidase effects did not result from differences in intracellular HA, sulfated glycosaminoglycan concentration, apoptosis, or levels of HA receptors, all of which remained unchanged. Similarly, knockdown of UDP-glucose 6-dehydrogenase (UGDH) using lentiviral shRNA effectively decreased HA production but did not affect proliferation rate. Overall, these data suggest that HA levels in the human epidermis are not directly correlated with keratinocyte proliferation and differentiation and that incubation of cells with 4MU cannot equate with HA removal. PMID:26627828

Chemokines, their receptors, and transplant outcome.

PubMed

Colvin, Bridget L; Thomson, Angus W

2002-07-27

Organ transplant rejection is mediated largely by circulating peripheral leukocytes induced to infiltrate the graft by various inflammatory stimuli. Of these, chemotactic cytokines called chemokines, expressed by inflamed graft tissues, as well as by early innate-responding leukocytes that infiltrate the graft, are responsible for the recruitment of alloreactive leukocytes. This report discusses the impact of these leukocyte-directing proteins on transplant outcome and novel therapeutic approaches for antirejection therapy based on targeting of chemokines and/or their receptors.

Synthetic antimicrobial and LPS-neutralising peptides suppress inflammatory and immune responses in skin cells and promote keratinocyte migration.

PubMed

Pfalzgraff, Anja; Heinbockel, Lena; Su, Qi; Gutsmann, Thomas; Brandenburg, Klaus; Weindl, Günther

2016-08-11

The stagnation in the development of new antibiotics and the concomitant high increase of resistant bacteria emphasize the urgent need for new therapeutic options. Antimicrobial peptides are promising agents for the treatment of bacterial infections and recent studies indicate that Pep19-2.5, a synthetic anti-lipopolysaccharide (LPS) peptide (SALP), efficiently neutralises pathogenicity factors of Gram-negative (LPS) and Gram-positive (lipoprotein/-peptide, LP) bacteria and protects against sepsis. Here, we investigated the potential of Pep19-2.5 and the structurally related compound Pep19-4LF for their therapeutic application in bacterial skin infections. SALPs inhibited LP-induced phosphorylation of NF-κB p65 and p38 MAPK and reduced cytokine release and gene expression in primary human keratinocytes and dermal fibroblasts. In LPS-stimulated human monocyte-derived dendritic cells and Langerhans-like cells, the peptides blocked IL-6 secretion, downregulated expression of maturation markers and inhibited dendritic cell migration. Both SALPs showed a low cytotoxicity in all investigated cell types. Furthermore, SALPs markedly promoted cell migration via EGFR transactivation and ERK1/2 phosphorylation and accelerated artificial wound closure in keratinocytes. Peptide-induced keratinocyte migration was mediated by purinergic receptors and metalloproteases. In contrast, SALPs did not affect proliferation of keratinocytes. Conclusively, our data suggest a novel therapeutic target for the treatment of patients with acute and chronic skin infections.

Synthetic antimicrobial and LPS-neutralising peptides suppress inflammatory and immune responses in skin cells and promote keratinocyte migration

PubMed Central

Pfalzgraff, Anja; Heinbockel, Lena; Su, Qi; Gutsmann, Thomas; Brandenburg, Klaus; Weindl, Günther

2016-01-01

The stagnation in the development of new antibiotics and the concomitant high increase of resistant bacteria emphasize the urgent need for new therapeutic options. Antimicrobial peptides are promising agents for the treatment of bacterial infections and recent studies indicate that Pep19-2.5, a synthetic anti-lipopolysaccharide (LPS) peptide (SALP), efficiently neutralises pathogenicity factors of Gram-negative (LPS) and Gram-positive (lipoprotein/-peptide, LP) bacteria and protects against sepsis. Here, we investigated the potential of Pep19-2.5 and the structurally related compound Pep19-4LF for their therapeutic application in bacterial skin infections. SALPs inhibited LP-induced phosphorylation of NF-κB p65 and p38 MAPK and reduced cytokine release and gene expression in primary human keratinocytes and dermal fibroblasts. In LPS-stimulated human monocyte-derived dendritic cells and Langerhans-like cells, the peptides blocked IL-6 secretion, downregulated expression of maturation markers and inhibited dendritic cell migration. Both SALPs showed a low cytotoxicity in all investigated cell types. Furthermore, SALPs markedly promoted cell migration via EGFR transactivation and ERK1/2 phosphorylation and accelerated artificial wound closure in keratinocytes. Peptide-induced keratinocyte migration was mediated by purinergic receptors and metalloproteases. In contrast, SALPs did not affect proliferation of keratinocytes. Conclusively, our data suggest a novel therapeutic target for the treatment of patients with acute and chronic skin infections. PMID:27509895

Regulation of inflammatory chemokine receptors on blood T cells associated to the circulating versus liver chemokines in dengue fever.

PubMed

de-Oliveira-Pinto, Luzia Maria; Marinho, Cíntia Ferreira; Povoa, Tiago Fajardo; de Azeredo, Elzinandes Leal; de Souza, Luiza Assed; Barbosa, Luiza Damian Ribeiro; Motta-Castro, Ana Rita C; Alves, Ada M B; Ávila, Carlos André Lins; de Souza, Luiz José; da Cunha, Rivaldo Venâncio; Damasco, Paulo Vieira; Paes, Marciano Viana; Kubelka, Claire Fernandes

2012-01-01

Little is known about the role of chemokines/chemokines receptors on T cells in natural DENV infection. Patients from DENV-2 and -3- outbreaks were studied prospectively during the acute or convalescent phases. Expression of chemokine receptor and activation markers on lymphocyte subpopulations were determined by flow cytometry analysis, plasma chemokine ligands concentrations were measured by ELISA and quantification of CCL5/RANTES(+) cells in liver tissues from fatal dengue cases was performed by immunochemistry. In the acute DENV-infection, T-helper/T-cytotoxic type-1 cell (Th1/Tc1)-related CCR5 is significantly higher expressed on both CD4 and CD8 T cells. The Th1-related CXCR3 is up-regulated among CD4 T cells and Tc2-related CCR4 is up-regulated among CD8 T cells. In the convalescent phase, all chemokine receptor or chemokine ligand expression tends to reestablish control healthy levels. Increased CCL2/MCP-1 and CCL4/MIP-1β but decreased CCL5/RANTES levels were observed in DENV-patients during acute infection. Moreover, we showed an increased CD107a expression on CCR5 or CXCR3-expressing T cells and higher expression of CD29, CD44(HIGH) and CD127(LOW) markers on CCR4-expressing CD8 T cells in DENV-patients when compared to controls. Finally, liver from dengue fatal patients showed increased number of cells expressing CCL5/RANTES in three out of four cases compared to three death from a non-dengue patient. In conclusion, both Th1-related CCR5 and CXCR3 among CD4 T cells have a potential ability to exert cytotoxicity function. Moreover, Tc1-related CCR5 and Tc2-related CCR4 among CD8 T cells have a potential ability to exert effector function and migration based on cell markers evaluated. The CCR5 expression would be promoting an enhanced T cell recruitment into liver, a hypothesis that is corroborated by the CCL5/RANTES increase detected in hepatic tissue from dengue fatal cases. The balance between protective and pathogenic immune response mediated by

Regulation of Inflammatory Chemokine Receptors on Blood T Cells Associated to the Circulating Versus Liver Chemokines in Dengue Fever

PubMed Central

Povoa, Tiago Fajardo; de Azeredo, Elzinandes Leal; de Souza, Luiza Assed; Barbosa, Luiza Damian Ribeiro; Motta-Castro, Ana Rita C.; Alves, Ada M. B.; Ávila, Carlos André Lins; de Souza, Luiz José; da Cunha, Rivaldo Venâncio; Damasco, Paulo Vieira; Paes, Marciano Viana; Kubelka, Claire Fernandes

2012-01-01

Little is known about the role of chemokines/chemokines receptors on T cells in natural DENV infection. Patients from DENV-2 and -3- outbreaks were studied prospectively during the acute or convalescent phases. Expression of chemokine receptor and activation markers on lymphocyte subpopulations were determined by flow cytometry analysis, plasma chemokine ligands concentrations were measured by ELISA and quantification of CCL5/RANTES+ cells in liver tissues from fatal dengue cases was performed by immunochemistry. In the acute DENV-infection, T-helper/T-cytotoxic type-1 cell (Th1/Tc1)-related CCR5 is significantly higher expressed on both CD4 and CD8 T cells. The Th1-related CXCR3 is up-regulated among CD4 T cells and Tc2-related CCR4 is up-regulated among CD8 T cells. In the convalescent phase, all chemokine receptor or chemokine ligand expression tends to reestablish control healthy levels. Increased CCL2/MCP-1 and CCL4/MIP-1β but decreased CCL5/RANTES levels were observed in DENV-patients during acute infection. Moreover, we showed an increased CD107a expression on CCR5 or CXCR3-expressing T cells and higher expression of CD29, CD44HIGH and CD127LOW markers on CCR4-expressing CD8 T cells in DENV-patients when compared to controls. Finally, liver from dengue fatal patients showed increased number of cells expressing CCL5/RANTES in three out of four cases compared to three death from a non-dengue patient. In conclusion, both Th1-related CCR5 and CXCR3 among CD4 T cells have a potential ability to exert cytotoxicity function. Moreover, Tc1-related CCR5 and Tc2-related CCR4 among CD8 T cells have a potential ability to exert effector function and migration based on cell markers evaluated. The CCR5 expression would be promoting an enhanced T cell recruitment into liver, a hypothesis that is corroborated by the CCL5/RANTES increase detected in hepatic tissue from dengue fatal cases. The balance between protective and pathogenic immune response mediated by chemokines

A hemidesmosomal protein regulates actin dynamics and traction forces in motile keratinocytes

PubMed Central

Hiroyasu, Sho; Colburn, Zachary T.; Jones, Jonathan C. R.

2016-01-01

During wound healing of the skin, keratinocytes disassemble hemidesmosomes and reorganize their actin cytoskeletons in order to exert traction forces on and move directionally over the dermis. Nonetheless, the transmembrane hemidesmosome component collagen XVII (ColXVII) is found in actin-rich lamella, situated behind the lamellipodium. A set of actin bundles, along which ColXVII colocalizes with actinin4, is present at each lamella. Knockdown of either ColXVII or actinin4 not only inhibits directed migration of keratinocytes but also relieves constraints on actin bundle retrograde movement at the site of lamella, such that actin bundle movement is enhanced more than 5-fold. Moreover, whereas control keratinocytes move in a stepwise fashion over a substrate by generating alternating traction forces, of up to 1.4 kPa, at each flank of the lamellipodium, ColXVII knockdown keratinocytes fail to do so. In summary, our data indicate that ColXVII-actinin4 complexes at the lamella of a moving keratinocyte regulate actin dynamics, thereby determining the direction of cell movement.—Hiroyasu, S., Colburn, Z. T., Jones, J. C. R. A hemidesmosomal protein regulates actin dynamics and traction forces in motile keratinocytes. PMID:26936359

Astronaut Edwin Aldrin undergoes zero-gravity training aboard KC-135

NASA Image and Video Library

1969-07-15

S69-39269 (10 July 1969) --- Astronaut Edwin E. Aldrin Jr., lunar module pilot of the Apollo 11 lunar landing mission, undergoes zero-gravity training aboard a U.S. Air Force KC-135 jet aircraft from nearby Patrick Air Force Base, Florida. Aldrin is wearing an Extravehicular Mobility Unit (EMU), the type of equipment which he will wear on the lunar surface.

Polymeric membranes modulate human keratinocyte differentiation in specific epidermal layers.

PubMed

Salerno, Simona; Morelli, Sabrina; Giordano, Francesca; Gordano, Amalia; Bartolo, Loredana De

2016-10-01

In vitro models of human bioengineered skin substitutes are an alternative to animal experimentation for testing the effects and toxicity of drugs, cosmetics and pollutants. For the first time specific and distinct human epidermal strata were engineered by using membranes and keratinocytes. To this purpose, biodegradable membranes of chitosan (CHT), polycaprolactone (PCL) and a polymeric blend of CHT-PCL were prepared by phase-inversion technique and characterized in order to evaluate their morphological, physico-chemical and mechanical properties. The capability of membranes to modulate keratinocyte differentiation inducing specific interactions in epidermal membrane systems was investigated. The overall results demonstrated that the membrane properties strongly influence the cell morpho-functional behaviour of human keratinocytes, modulating their terminal differentiation, with the creation of specific epidermal strata or a fully proliferative epidermal multilayer system. In particular, human keratinocytes adhered on CHT and CHT-PCL membranes, forming the structure of the epidermal top layers, such as the corneum and granulosum strata, characterized by withdrawal or reduction from the cell cycle and cell proliferation. On the PCL membrane, keratinocytes developed an epidermal basal lamina, with high proliferating cells that stratified and migrated over time to form a complete differentiating epidermal multilayer system. Copyright © 2016 Elsevier B.V. All rights reserved.

Human lactoferrin stimulates skin keratinocyte function and wound re-epithelialization.

PubMed

Tang, L; Wu, J J; Ma, Q; Cui, T; Andreopoulos, F M; Gil, J; Valdes, J; Davis, S C; Li, J

2010-07-01

Human lactoferrin (hLF), a member of the transferrin family, is known for its antimicrobial and anti-inflammatory effects. Recent studies on various nonskin cell lines indicate that hLF may have a stimulatory effect on cell proliferation. To study the potential role of hLF in wound re-epithelialization. The effects of hLF on cell growth, migration, attachment and survival were assessed, with a rice-derived recombinant hLF (holo-rhLF), using proliferation analysis, scratch migration assay, calcein-AM/propidium iodide staining and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL) method, respectively. The mechanisms of hLF on cell proliferation and migration were explored using specific pathway inhibitors. The involvement of lactoferrin receptor low-density lipoprotein receptor-related protein 1 (LRP1) was examined with RNA interference technique. An in vivo swine second-degree burn wound model was also used to assess wound re-epithelialization. Studies revealed that holo-rhLF significantly stimulated keratinocyte proliferation which could be blocked by mitogen-activated protein kinase (MAPK) kinase 1 inhibitor. Holo-rhLF also showed strong promoting effects on keratinocyte migration, which could be blocked by either inhibition of the MAPK, Src and Rho/ROCK pathways, or downregulation of the LRP1 receptor. With cells under starving or 12-O-tetradecanoylphorbol-13-acetate exposure, the addition of holo-rhLF was found greatly to increase cell viability and inhibit cell apoptosis. Additionally, holo-rhLF significantly increased the rate of wound re-epithelialization in swine second-degree burn wounds. Our studies demonstrate the direct effects of holo-rhLF on wound re-epithelialization including the enhancement of keratinocyte proliferation and migration as well as the protection of cells from apoptosis. The data strongly indicate its potential therapeutic applications in wound healing.

The role of alpha3beta1 integrin in determining the supramolecular organization of laminin-5 in the extracellular matrix of keratinocytes.

PubMed

deHart, Gregory W; Healy, Kevin E; Jones, Jonathan C R

2003-02-01

Analyses of mice with targeted deletions in the genes for alpha3 and beta1 integrin suggest that the alpha3beta1 integrin heterodimer likely determines the organization of the extracellular matrix within the basement membrane of skin. Here we tested this hypothesis using keratinocytes derived from alpha3 integrin-null mice. We have compared the organizational state of laminin-5, a ligand of alpha3beta1 integrin, in the matrix of wild-type keratinocytes with that of laminin-5 in the matrix of alpha3 integrin-null cells. Laminin-5 distributes diffusely in arc structures in the matrix of wild-type mouse keratinocytes, whereas laminin-5 is organized into linear, spike-like arrays by the alpha3 integrin-null cells. The fact that alpha3 integrin-null cells are deficient in their ability to assemble a proper laminin-5 matrix is also shown by their failure to remodel laminin-5 when plated onto surfaces coated with purified laminin-5 protein. In sharp contrast, wild-type keratinocytes organize exogenously added laminin-5 into discrete ring-like organizations. These findings led us next to assess whether differences in laminin-5 organization in the matrix of the wild-type and alpha3 integrin-null cells impact cell behavior. Our results indicate that alpha3 integrin-null cells are more motile than their wild-type counterparts and leave extensive trails of laminin-5 over the surface on which they move. Moreover, HEK 293 cells migrate significantly more on the laminin-5-rich matrix derived from the alpha3 integrin-null cells than on the wild-type keratinocyte laminin-5 matrix. In addition, alpha3 integrin-null cells show low strength of adhesion to surfaces coated with purified laminin-5 compared to wild-type cells although both the wild type and the alpha3 integrin-null keratinocytes adhere equally strongly to laminin-5 that has been organized into arrays by other epithelial cells. These data suggest: (1) that alpha3beta1 integrin plays an important role in determining the

EBI1/CCR7 is a new member of dendritic cell chemokine receptor that is up-regulated upon maturation.

PubMed

Yanagihara, S; Komura, E; Nagafune, J; Watarai, H; Yamaguchi, Y

1998-09-15

Dendritic cells (DC) that are stimulated with inflammatory mediators can maturate and migrate from nonlymphoid tissues to lymphoid organs to initiate T cell-mediated immune responses. This migratory step is closely related to the maturation of the DC. In an attempt to identify chemokine receptors that might influence migration and are selectively expressed in mature DC, we have discovered that the chemokine receptor, EBI1/CCR7, is strikingly up-regulated upon maturation in three distinct culture systems: 1) mouse bone marrow-derived DC, 2) mouse epidermal Langerhans cells, and 3) human monocyte-derived DC. The EBI1/CCR7 expressed in mature DC is functional because ELC/MIP-3beta, recently identified as a ligand of EBI1/CCR7, induces a rise in intracellular free calcium concentrations and directional migration of human monocyte-derived mature DC (HLA-DRhigh, CD1a(low), CD14-, CD25+, CD83+, and CD86high) in a dose-dependent manner, but not of immature DC (HLA-DRlow, CD1a(high), CD14-, CD25-, CD83-, and CD86-). In contrast, macrophage inflammatory protein-1alpha (MIP-1alpha), monocyte chemotactic protein-3 (MCP-3), and RANTES are active on immature DC but not on mature DC. Thus, it seems likely that MIP-1alpha, MCP-3, and RANTES can mediate the migration of immature DC located in peripheral sites, whereas ELC/MIP-3beta can direct the migration of Ag-carrying DC from peripheral inflammatory sites, where DC are stimulated to up-regulate the expression of EBI1/CCR7, to lymphoid organs. It is postulated that different chemokines and chemokine receptors are involved in DC migration in vivo, depending on the maturation state of DC.

Human Mas-Related G Protein-Coupled Receptors-X1 Induce Chemokine Receptor 2 Expression in Rat Dorsal Root Ganglia Neurons and Release of Chemokine Ligand 2 from the Human LAD-2 Mast Cell Line

PubMed Central

Solinski, Hans Jürgen; Petermann, Franziska; Rothe, Kathrin; Boekhoff, Ingrid; Gudermann, Thomas; Breit, Andreas

2013-01-01

Primate-specific Mas-related G protein-coupled receptors-X1 (MRGPR-X1) are highly enriched in dorsal root ganglia (DRG) neurons and induce acute pain. Herein, we analyzed effects of MRGPR-X1 on serum response factors (SRF) or nuclear factors of activated T cells (NFAT), which control expression of various markers of chronic pain. Using HEK293, DRG neuron-derived F11 cells and cultured rat DRG neurons recombinantly expressing human MRGPR-X1, we found activation of a SRF reporter gene construct and induction of the early growth response protein-1 via extracellular signal-regulated kinases-1/2 known to play a significant role in the development of inflammatory pain. Furthermore, we observed MRGPR-X1-induced up-regulation of the chemokine receptor 2 (CCR2) via NFAT, which is considered as a key event in the onset of neuropathic pain and, so far, has not yet been described for any endogenous neuropeptide. Up-regulation of CCR2 is often associated with increased release of its endogenous agonist chemokine ligand 2 (CCL2). We also found MRGPR-X1-promoted release of CCL2 in a human connective tissue mast cell line endogenously expressing MRGPR-X1. Thus, we provide first evidence to suggest that MRGPR-X1 induce expression of chronic pain markers in DRG neurons and propose a so far unidentified signaling circuit that enhances chemokine signaling by acting on two distinct yet functionally co-operating cell types. Given the important role of chemokine signaling in pain chronification, we propose that interruption of this signaling circuit might be a promising new strategy to alleviate chemokine-promoted pain. PMID:23505557

KC-135A Winglet Flight Flutter Program

NASA Technical Reports Server (NTRS)

Kehoe, M. W.

1982-01-01

The evaluation techniques, results and conclusions for the flight flutter testing conducted on a KC-135A airplane configured with and without winglets are discussed. Test results are presented for the critical symmetric and antisymmetric modes for a fuel distribution that consisted of 10,000 pounds in each wing main tank and empty reserve tanks. The results indicated that a lightly damped oscillation was experienced for a winglet configuration of a 0 deg cant and -4 deg incidence. The effects of cant and incidence angle variation on the critical modes are also discussed. Lightly damped oscillations were not encountered for any other winglet cant and incidence angles tested.

Dual-band infrared (DBIR) imaging inspections of Boeing 737 and KC-135 aircraft panels

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

Del Grande, N.K.; Dolan, K.W.; Durbin, P.F.

1993-08-27

We apply dual-band infrared (DBIR) imaging as a dynamic thermal tomography tool for wide area inspection of a Boeing 737 aircraft, and several Boeing KC-135 aircraft panels. Our analyses are discussed in this report. After flash-heating the aircraft skin, we record synchronized DBIR images every 40 ms, from onset to 8 seconds after the heat flash. We analyze selective DBIR image ratios which enhance surface temperature contrast and remove surface-emissivity clutter (from dirt, dents, tape, markings, ink, sealants, uneven paint, paint stripper, exposed metal and roughness variations). The Boeing 737 and KC-135 aircraft fuselage panels have varying percent thickness lossesmore » from corrosion. We established the correlation of percent thickness loss with surface temperature rise (above ambient) for a partially corroded F-18 wing box structure and several aluminum reference panels. Based on this correlation, lap splice temperatures rise 1{degrees}C per 24 {plus_minus} 5 % material loss at 0.4 s after the heat flash. We show tables, charts and temperature maps of typical lap splice material losses for the riveted (and bonded) Boeing 737, and the riveted (but unbonded) Boeing KC-135. We map the fuselage composite thermal inertia, based on the (inverse) slope of the surface temperature versus inverse square root of time. Composite thermal inertia maps characterize shallow skin defects within the lap splice at early times (<0.3 s) and deeper skin defects within the lap splice at late times (>0.4 s). Late time composite thermal inertia maps depict where corrosion-related thickness losses occur. Lap splice sites on a typical Boeing KC-135 panel with low composite thermal inertia values had high skin-thickness losses from corrosion.« less

Human keratinocytes are efficiently immortalized by a Rho kinase inhibitor

PubMed Central

Chapman, Sandra; Liu, Xuefeng; Meyers, Craig; Schlegel, Richard; McBride, Alison A.

2010-01-01

Primary human keratinocytes are useful for studying the pathogenesis of many different diseases of the cutaneous and mucosal epithelia. In addition, they can form organotypic tissue equivalents in culture that can be used as epidermal autografts for wound repair as well as for the delivery of gene therapy. However, primary keratinocytes have a finite lifespan in culture that limits their proliferative capacity and clinical use. Here, we report that treatment of primary keratinocytes (originating from 3 different anatomical sites) with Y-27632, a Rho kinase inhibitor, greatly increased their proliferative capacity and resulted in efficient immortalization without detectable cell crisis. More importantly, the immortalized cells displayed characteristics typical of primary keratinocytes; they had a normal karyotype and an intact DNA damage response and were able to differentiate into a stratified epithelium. This is the first example to our knowledge of a defined chemical compound mediating efficient cell immortalization, and this finding could have wide-ranging and profound investigational and medical applications. PMID:20516646

Astronaut Catherine G. Coleman aboard KC-135 aircraft

NASA Image and Video Library

1994-01-10

S94-26350 (10 Jan. 1994) --- Astronaut Catherine G. Coleman seems to enjoy the brief period of weightlessness she is sharing with fellow members of the 1992 class of astronauts. The weightless experience was afforded by a special parabolic pattern flown by NASA?s KC-135 ?zero gravity? aircraft. Left to right behind her are astronauts Michael E. Lopez-Alegria, Kevin R. Kregel and Winston E. Scott. EDITOR?S NOTE: Since this photograph was taken the four have been named to flights as follows: Kregel, STS-70; Scott, STS-72.

Association Between Statin Use and Risk for Keratinocyte Carcinoma in the Veterans Affairs Topical Tretinoin Chemoprevention Trial

PubMed Central

Dore, David D.; Lapane, Kate L.; Trivedi, Amal N.; Mor, Vincent; Weinstock, Martin A.

2013-01-01

Background Recent evidence suggests that statins may prevent cancer. Objective To quantify the association between statin use and the occurrence of keratinocyte carcinoma in high-risk veterans. Design Cohort study. Setting 6 Veterans Affairs medical centers. Participants 1037 participants of the Veterans Affairs Topical Tretinoin Chemoprevention Trial, a randomized, multicenter, double-blind, vehicle-controlled trial of topical tretinoin, 0.1%, for prevention of keratinocyte carcinoma conducted from November 1998 to November 2004. Measurements Time to first occurrence of keratinocyte carcinoma on the face or ears. Participants using a statin at randomization, according to the Veterans Affairs Pharmacy Benefits Management database, were considered exposed. Study dermatologists conducted physical examinations at baseline and every 6 months during follow-up. The association between statin use at randomization and the outcome was evaluated by using propensity score matching (n = 608) and Cox proportional hazards regression (n = 1037). Results Among the 1037 participants, 37% used a statin at randomization (n = 397) for a median duration of at least 900 days over a median follow-up of 3.5 years. In the propensity score-matched analysis, statin use at randomization was not associated with keratinocyte carcinoma (rate ratio, 0.92 [95% CI, 0.73 to 1.16]), a finding that was consistent with the estimates derived from the Cox proportional hazards regression (rate ratio, 0.84 [CI, 0.70 to 1.02]). Limitations The extent of residual confounding is unknown, and the confidence bounds around the measures of association were wide. These data may not be generalizable to lower-risk populations. Conclusion These data show no conclusive or consistent relationship between long-term statin use and risk for keratinocyte carcinoma. Funding Department of Veterans Affairs, Agency for Healthcare Research and Quality, American Cancer Society, and National Institutes of Health. PMID:19124815

Rab11b mediates melanin transfer between donor melanocytes and acceptor keratinocytes via coupled exo/endocytosis.

PubMed

Tarafder, Abul K; Bolasco, Giulia; Correia, Maria S; Pereira, Francisco J C; Iannone, Lucio; Hume, Alistair N; Kirkpatrick, Niall; Picardo, Mauro; Torrisi, Maria R; Rodrigues, Inês P; Ramalho, José S; Futter, Clare E; Barral, Duarte C; Seabra, Miguel C

2014-04-01

The transfer of melanin from melanocytes to keratinocytes is a crucial process underlying maintenance of skin pigmentation and photoprotection against UV damage. Here, we present evidence supporting coupled exocytosis of the melanin core, or melanocore, by melanocytes and subsequent endocytosis by keratinocytes as a predominant mechanism of melanin transfer. Electron microscopy analysis of human skin samples revealed three lines of evidence supporting this: (1) the presence of melanocores in the extracellular space; (2) within keratinocytes, melanin was surrounded by a single membrane; and (3) this membrane lacked the melanosomal membrane protein tyrosinase-related protein 1 (TYRP1). Moreover, co-culture of melanocytes and keratinocytes suggests that melanin exocytosis is specifically induced by keratinocytes. Furthermore, depletion of Rab11b, but not Rab27a, caused a marked decrease in both keratinocyte-stimulated melanin exocytosis and transfer to keratinocytes. Thus, we propose that the predominant mechanism of melanin transfer is keratinocyte-induced exocytosis, mediated by Rab11b through remodeling of the melanosome membrane, followed by subsequent endocytosis by keratinocytes.

Serum CXCL10, CXCL11, CXCL12, and CXCL14 chemokine patterns in patients with acute liver injury.

PubMed

Chalin, Arnaud; Lefevre, Benjamin; Devisme, Christelle; Pronier, Charlotte; Carrière, Virginie; Thibault, Vincent; Amiot, Laurence; Samson, Michel

2018-06-04

The chemokines CXCL10 (interferon ϒ-inducible protein 10 [IP-10]), CXCL11 (Human interferon inducible T cell alpha chemokine [I-TAC]), CXCL12 (stromal cell derived factor 1 [SDF-1]), and CXCL14 (breast and kidney-expressed chemokine [BRAK]) are involved in cell recruitment, migration, activation, and homing in liver diseases and have been shown to be upregulated during acute liver injury in animal models. However, their expression in patients with acute liver injury is unknown. Here, we aimed to provide evidence of the presence of circulating CXCL10, CXCL11, CXCL12, and CXCL14 during human acute liver injury to propose new inflammation biomarkers for acute liver injury. We analyzed the serum concentration of the studied chemokines in healthy donors (n = 36) and patients (n = 163) with acute liver injuries of various etiologies. Serum CXCL10, CXCL11 and CXCL12 levels were elevated in all the studied groups except biliary diseases for CXCL11. CXCL14 was associated with only acute viral infection and vascular etiologies. The strongest correlation was found between the IFN-inducible studied chemokines (CXCL10 and CXCL11) in all patients and more specifically in the acute viral infection group. These data provide evidence for the presence of circulating CXCL10, CXCL11, CXCL12, and CXCL14 during acute liver injury and are consistent with data obtained in animal models. CXCL10, CXCL11 and CXCL12 were the most highly represented and CXCL14 the least represented chemokines. Differential expression patterns were obtained depending on acute liver injury etiology, suggesting the potential use of these chemokines as acute liver injury biomarkers. Copyright © 2018. Published by Elsevier Ltd.

In vivo evolution of HIV-1 co-receptor usage and sensitivity to chemokine-mediated suppression.

PubMed

Scarlatti, G; Tresoldi, E; Björndal, A; Fredriksson, R; Colognesi, C; Deng, H K; Malnati, M S; Plebani, A; Siccardi, A G; Littman, D R; Fenyö, E M; Lusso, P

1997-11-01

Following the identification of the C-C chemokines RANTES, MIP-1alpha and MIP-1beta as major human immunodeficiency virus (HIV)-suppressive factors produced by CD8+ T cells, several chemokine receptors were found to serve as membrane co-receptors for primate immunodeficiency lentiretroviruses. The two most widely used co-receptors thus far recognized, CCR5 and CXCR4, are expressed by both activated T lymphocytes and mononuclear phagocytes. CCR5, a specific RANTES, MIP-1alpha and MIP-1 receptor, is used preferentially by non-MT2-tropic HIV-1 and HIV-2 strains and by simian immunodeficiency virus (SIV), whereas CXCR4, a receptor for the C-X-C chemokine SDF-1, is used by MT2-tropic HIV-1 and HIV-2, but not by SIV. Other receptors with a more restricted cellular distribution, such as CCR2b, CCR3 and STRL33, can also function as co-receptors for selected viral isolates. The third variable region (V3) of the gp120 envelope glycoprotein of HIV-1 has been fingered as a critical determinant of the co-receptor choice. Here, we document a consistent pattern of evolution of viral co-receptor usage and sensitivity to chemokine-mediated suppression in a longitudinal follow-up of children with progressive HIV-1 infection. Viral isolates obtained during the asymptomatic stages generally used only CCR5 as a co-receptor and were inhibited by RANTES, MIP-1alpha and MIP-1beta, but not by SDF-1. By contrast, the majority of the isolates derived after the progression of the disease were resistant to C-C chemokines, having acquired the ability to use CXCR4 and, in some cases, CCR3, while gradually losing CCR5 usage. Surprisingly, most of these isolates were also insensitive to SDF-1, even when used in combination with RANTES. An early acquisition of CXCR4 usage predicted a poor prognosis. In children who progressed to AIDS without a shift to CXCR4 usage, all the sequential isolates were CCR5-dependent but showed a reduced sensitivity to C-C chemokines. Discrete changes in the V3 domain

Chemokine receptor antagonists: part 2.

PubMed

Pease, James E; Horuk, Richard

2009-02-01

The first part of this two-part review discussed approaches to generating antagonists for some of the CC chemokine receptors, including CCR1, CCR2, CCR3, and CCR4. This second part of the series concludes the review by describing antagonists for CCR5, CCR8, CCR9, CXCR3, CXCR4, and promiscuous antagonists. Chemokine receptor antagonists have found mixed success as therapeutics. Although one antagonist--maraviroc, a CCR5 inhibitor to treat AIDS--has been registered as an approved drug, this is the only success so far. There have been many failures in the clinic and we discuss the idea of promiscuous receptor antagonists as an alternative approach.

The effect of aliskiren on urinary cytokine/chemokine responses to clamped hyperglycaemia in type 1 diabetes.

PubMed

Cherney, David Z I; Reich, Heather N; Scholey, James W; Daneman, Denis; Mahmud, Farid H; Har, Ronnie L H; Sochett, Etienne B

2013-10-01

Acute clamped hyperglycaemia activates the renin-angiotensin-aldosterone system (RAAS) and increases the urinary excretion of inflammatory cytokines/chemokines in patients with uncomplicated type 1 diabetes mellitus. Our objective was to determine whether blockade of the RAAS would blunt the effect of acute hyperglycaemia on urinary cytokine/chemokine excretion, thereby giving insights into potentially protective effects of these agents prior to the onset of clinical nephropathy. Blood pressure, renal haemodynamic function (inulin and para-aminohippurate clearances) and urinary cytokines/chemokines were measured after 6 h of clamped euglycaemia (4-6 mmol/l) and hyperglycaemia (9-11 mmol/l) on two consecutive days in patients with type 1 diabetes mellitus (n = 27) without overt nephropathy. Measurements were repeated after treatment with aliskiren (300 mg daily) for 30 days. Before aliskiren, clamped hyperglycaemia increased filtration fraction (from 0.188 ± 0.007 to 0.206 ± 0.007, p = 0.003) and urinary fibroblast growth factor-2 (FGF2), IFN-α2 and macrophage-derived chemokine (MDC) (p < 0.005). After aliskiren, the filtration fraction response to hyperglycaemia was abolished, resulting in a lower filtration fraction after aliskiren under clamped hyperglycaemic conditions (p = 0.004), and none of the biomarkers increased in response to hyperglycaemia. Aliskiren therapy also reduced levels of urinary eotaxin, FGF2, IFN-α2, IL-2 and MDC during clamped hyperglycaemia (p < 0.005). The increased urinary excretion of inflammatory cytokines/chemokines in response to acute hyperglycaemia is blunted by RAAS blockade in humans with uncomplicated type 1 diabetes mellitus.

KC-135 winglet flight results

NASA Technical Reports Server (NTRS)

Montoya, L. C.

1981-01-01

Three KC-135 winglet configurations were flight tested for cant/incidence angles of 15 deg/-4 deg, 15 deg/-2 deg, and 0 deg/-4 deg, as well as the basic wing. The flight results for the 15 deg/-4 deg and basic wing configurations confirm the wind tunnel predicted 7% incremental decrease in total drag at cruise conditions. The 15 deg/-4 configuration flight measured wing and winglet pressure distributions, loads, stability and control, flutter, and buffet also correlate well with predicted values. The only unexpected flight results as compared with analytical predictions is a flutter speed decrease for the 0 deg/-4 deg configuration. The 15 deg/-2 deg configuration results show essentially the same incremental drag reduction as the 15 deg/-4 deg configuration; however, the flight loads are approximately 30% higher for the 15 deg/-2 deg configuration. The drag data for the 0 deg/-4 deg configuration show only a flight drag reduction.

Human amniotic epithelial stem cells promote wound healing by facilitating migration and proliferation of keratinocytes via ERK, JNK and AKT signaling pathways.

PubMed

Zhao, Bin; Liu, Jia-Qi; Zheng, Zhao; Zhang, Jun; Wang, Shu-Yue; Han, Shi-Chao; Zhou, Qin; Guan, Hao; Li, Chao; Su, Lin-Lin; Hu, Da-Hai

2016-07-01

Wound healing is a highly orchestrated physiological process consisting in a complex interaction of cellular and biochemical events. Human amniotic epithelial stem cells (HAESCs) have been shown to be an attractive resource for wound healing because they are primitive stem cells. However, the exact effects of amnion-derived stem cells on the migration or proliferation of keratinocytes and their potential mechanism are not fully understood. We have found that HAESCs accelerate the migration of keratinocytes and induce a remarkable increase in the activity of phospho-ERK, phospho-JNK, and phospho-AKT, the blockade of which by their specific inhibitors significantly inhibits migration induced by HAESC-conditioned medium (CM). Furthermore, the co-culture of keratinocytes with HAESCs up-regulates the expression levels of cell proliferation proteins Cyclin D1, Cyclin D3 and Mdm2. In vivo animal experiments have shown that HAESC-CM improves wound healing, whereas blockade with ERK, JNK and AKT inhibitors significantly impairs wound healing. Taken together, these results reveal, for the first time, that HAESCs promote wound healing by facilitating the migration and proliferation of keratinocytes via ERK, JNK and AKT signaling pathways and might be a potential therapy in skin wound healing.

Early systemic bacterial dissemination and a rapid innate immune response characterize genetic resistance to plague of SEG mice.

PubMed

Demeure, Christian E; Blanchet, Charlène; Fitting, Catherine; Fayolle, Corinne; Khun, Huot; Szatanik, Marek; Milon, Geneviève; Panthier, Jean-Jacques; Jaubert, Jean; Montagutelli, Xavier; Huerre, Michel; Cavaillon, Jean-Marc; Carniel, Elisabeth

2012-01-01

Although laboratory mice are usually highly susceptible to Yersinia pestis, we recently identified a mouse strain (SEG) that exhibited an exceptional capacity to resist bubonic plague and used it to identify immune mechanisms associated with resistance. The kinetics of infection, circulating blood cells, granulopoiesis, lesions, and cellular populations in the spleen, and cytokine production in various tissues were compared in SEG and susceptible C57BL/6J mice after subcutaneous infection with the virulent Y. pestis CO92. Bacterial invasion occurred early (day 2) but was transient in SEG/Pas mice, whereas in C57BL/6J mice it was delayed but continuous until death. The bacterial load in all organs significantly correlated with the production of 5 cytokines (granulocyte colony-stimulating factor, keratinocyte-derived chemokine (KC), macrophage cationic peptide-1 (MCP-1), interleukin 1α, and interleukin 6) involved in monocyte and neutrophil recruitment. Indeed, higher proportions of these 2 cell types in blood and massive recruitment of F4/80(+)CD11b(-) macrophages in the spleen were observed in SEG/Pas mice at an early time point (day 2). Later times after infection (day 4) were characterized in C57BL/6J mice by destructive lesions of the spleen and impaired granulopoiesis. A fast and efficient Y. pestis dissemination in SEG mice may be critical for the triggering of an early and effective innate immune response necessary for surviving plague.

Structural insights into the interaction between a potent anti-inflammatory protein, viral CC chemokine inhibitor (vCCI), and the human CC chemokine, Eotaxin-1.

PubMed

Kuo, Nai-Wei; Gao, Yong-Guang; Schill, Megan S; Isern, Nancy; Dupureur, Cynthia M; Liwang, Patricia J

2014-03-07

Chemokines play important roles in the immune system, not only recruiting leukocytes to the site of infection and inflammation but also guiding cell homing and cell development. The soluble poxvirus-encoded protein viral CC chemokine inhibitor (vCCI), a CC chemokine inhibitor, can bind to human CC chemokines tightly to impair the host immune defense. This protein has no known homologs in eukaryotes and may represent a potent method to stop inflammation. Previously, our structure of the vCCI·MIP-1β (macrophage inflammatory protein-1β) complex indicated that vCCI uses negatively charged residues in β-sheet II to interact with positively charged residues in the MIP-1β N terminus, 20s region and 40s loop. However, the interactions between vCCI and other CC chemokines have not yet been fully explored. Here, we used NMR and fluorescence anisotropy to study the interaction between vCCI and eotaxin-1 (CCL11), a CC chemokine that is an important factor in the asthma response. NMR results reveal that the binding pattern is very similar to the vCCI·MIP-1β complex and suggest that electrostatic interactions provide a major contribution to binding. Fluorescence anisotropy results on variants of eotaxin-1 further confirm the critical roles of the charged residues in eotaxin-1. In addition, the binding affinity between vCCI and other wild type CC chemokines, MCP-1 (monocyte chemoattractant protein-1), MIP-1β, and RANTES (regulated on activation normal T cell expressed and secreted), were determined as 1.1, 1.2, and 0.22 nm, respectively. To our knowledge, this is the first work quantitatively measuring the binding affinity between vCCI and multiple CC chemokines.

Structural Insights into the Interaction between a Potent Anti-inflammatory Protein, Viral CC Chemokine Inhibitor (vCCI), and the Human CC Chemokine, Eotaxin-1*

PubMed Central

Kuo, Nai-Wei; Gao, Yong-Guang; Schill, Megan S.; Isern, Nancy; Dupureur, Cynthia M.; LiWang, Patricia J.

2014-01-01

Chemokines play important roles in the immune system, not only recruiting leukocytes to the site of infection and inflammation but also guiding cell homing and cell development. The soluble poxvirus-encoded protein viral CC chemokine inhibitor (vCCI), a CC chemokine inhibitor, can bind to human CC chemokines tightly to impair the host immune defense. This protein has no known homologs in eukaryotes and may represent a potent method to stop inflammation. Previously, our structure of the vCCI·MIP-1β (macrophage inflammatory protein-1β) complex indicated that vCCI uses negatively charged residues in β-sheet II to interact with positively charged residues in the MIP-1β N terminus, 20s region and 40s loop. However, the interactions between vCCI and other CC chemokines have not yet been fully explored. Here, we used NMR and fluorescence anisotropy to study the interaction between vCCI and eotaxin-1 (CCL11), a CC chemokine that is an important factor in the asthma response. NMR results reveal that the binding pattern is very similar to the vCCI·MIP-1β complex and suggest that electrostatic interactions provide a major contribution to binding. Fluorescence anisotropy results on variants of eotaxin-1 further confirm the critical roles of the charged residues in eotaxin-1. In addition, the binding affinity between vCCI and other wild type CC chemokines, MCP-1 (monocyte chemoattractant protein-1), MIP-1β, and RANTES (regulated on activation normal T cell expressed and secreted), were determined as 1.1, 1.2, and 0.22 nm, respectively. To our knowledge, this is the first work quantitatively measuring the binding affinity between vCCI and multiple CC chemokines. PMID:24482230

Protective Role of Mitochondrial Peroxiredoxin III against UVB-Induced Apoptosis of Epidermal Keratinocytes.

PubMed

Baek, Jin Young; Park, Sujin; Park, Jiyoung; Jang, Ji Yong; Wang, Su Bin; Kim, Sin Ri; Woo, Hyun Ae; Lim, Kyung Min; Chang, Tong-Shin

2017-06-01

UVB light induces generation of reactive oxygen species, ultimately leading to skin cell damage. Mitochondria are a major source of reactive oxygen species in UVB-irradiated skin cells, with increased levels of mitochondrial reactive oxygen species having been implicated in keratinocyte apoptosis. Peroxiredoxin III (PrxIII) is the most abundant and potent H 2 O 2 -removing enzyme in the mitochondria of most cell types. Here, the protective role of PrxIII against UVB-induced apoptosis of epidermal keratinocytes was investigated. Mitochondrial H 2 O 2 levels were differentiated from other types of ROS using mitochondria-specific fluorescent H 2 O 2 indicators. Upon UVB irradiation, PrxIII-knockdown HaCaT human keratinocytes and PrxIII-deficient (PrxIII -/- ) mouse primary keratinocytes exhibited enhanced accumulation of mitochondrial H 2 O 2 compared with PrxIII-expressing controls. Keratinocytes lacking PrxIII were subsequently sensitized to apoptosis through mitochondrial membrane potential loss, cardiolipin oxidation, cytochrome c release, and caspase activation. Increased UVB-induced epidermal tissue damage in PrxIII -/- mice was attributable to increased caspase-dependent keratinocyte apoptosis. Our findings show that mitochondrial H 2 O 2 is a key mediator in UVB-induced apoptosis of keratinocytes and that PrxIII plays a critical role in protecting epidermal keratinocytes against UVB-induced apoptosis through eliminating mitochondrial H 2 O 2 . These findings support the concept that reinforcing mitochondrial PrxIII defenses may help prevent UVB-induced skin damage such as inflammation, sunburn, and photoaging. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

[Evaluation of chemokines in tears of patients with infectious keratitis].

PubMed

Hori, Shinsuke; Shoji, Jun; Inada, Noriko; Sawa, Mitsuru

2013-02-01

To investigate the chemokine profile in tears of patients with infectious keratitis. Subjects were 32 eyes of 16 patients with infectious keratitis and 5 eyes of 5 healthy volunteers as a control. The patients with infectious keratitis were classified into two groups of eyes: 10 with bacterial keratitis and 6 with Acanthamoeba keratitis. Tear fluid was obtained from both eyes of the patients with infectious keratitis and from the right eyes of the control subjects using filter paper. Chemokine concentration (unit: Odu/mm2) and its profile in tears was analyzed using an antibody-array. In terms of chemokine profile in the bacterial keratitis group, the expression volume of interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) in the diseased eyes was significantly higher than in the healthy eyes (p < 0.05). The expression volume of mucosae-associated epithelial chemokines (MECs) in the diseased eyes of the bacterial keratitis group was significantly lower than in the healthy eyes of that group (p < 0.05). In the Acanthamoeba keratitis group, chemokines were not significantly increased in the diseased eyes compared with those in the healthy eyes. However, MCP-1 was increased in tears of the Acanthamoeba keratitis group. Regarding the chemokine ratio, the IL-8/MEC ratio in the diseased eyes of the Pseudomonas keratitis group and the MCP-1/IL-8 in the diseased eyes of the Acanthamoeba keratitis group showed a significantly high level (p < 0.05). We concluded that the analyses of the chemokine profile and chemokine ratio in the tears of infectious keratitis patients is useful as a clinical tear laboratory test to interpret the pathologic condition of infectious keratitis

Development of a Full-Thickness Human Skin Equivalent In Vitro Model Derived from TERT-Immortalized Keratinocytes and Fibroblasts

PubMed Central

Reijnders, Christianne M.A.; van Lier, Amanda; Roffel, Sanne; Kramer, Duco; Scheper, Rik J.

2015-01-01

Currently, human skin equivalents (HSEs) used for in vitro assays (e.g., for wound healing) make use of primary human skin cells. Limitations of primary keratinocytes and fibroblasts include availability of donor skin and donor variation. The use of physiologically relevant cell lines could solve these limitations. The aim was to develop a fully differentiated HSE constructed entirely from human skin cell lines, which could be applied for in vitro wound-healing assays. Skin equivalents were constructed from human TERT-immortalized keratinocytes and fibroblasts (TERT-HSE) and compared with native skin and primary HSEs. HSEs were characterized by hematoxylin–eosin and immunohistochemical stainings with markers for epidermal proliferation and differentiation, basement membrane (BM), fibroblasts, and the extracellular matrix (ECM). Ultrastructure was determined with electron microscopy. To test the functionality of the TERT-HSE, burn and cold injuries were applied, followed by immunohistochemical stainings, measurement of reepithelialization, and determination of secreted wound-healing mediators. The TERT-HSE was composed of a fully differentiated epidermis and a fibroblast-populated dermis comparable to native skin and primary HSE. The epidermis consisted of proliferating keratinocytes within the basal layer, followed by multiple spinous layers, a granular layer, and cornified layers. Within the TERT-HSE, the membrane junctions such as corneosomes, desmosomes, and hemidesmosomes were well developed as shown by ultrastructure pictures. Furthermore, the BM consisted of a lamina lucida and lamina densa comparable to native skin. The dermal matrix of the TERT-HSE was more similar to native skin than the primary construct, since collagen III, an ECM marker, was present in TERT-HSEs and absent in primary HSEs. After wounding, the TERT-HSE was able to reepithelialize and secrete inflammatory wound-healing mediators. In conclusion, the novel TERT-HSE, constructed entirely

Development of a Full-Thickness Human Skin Equivalent In Vitro Model Derived from TERT-Immortalized Keratinocytes and Fibroblasts.

PubMed

Reijnders, Christianne M A; van Lier, Amanda; Roffel, Sanne; Kramer, Duco; Scheper, Rik J; Gibbs, Susan

2015-09-01

Currently, human skin equivalents (HSEs) used for in vitro assays (e.g., for wound healing) make use of primary human skin cells. Limitations of primary keratinocytes and fibroblasts include availability of donor skin and donor variation. The use of physiologically relevant cell lines could solve these limitations. The aim was to develop a fully differentiated HSE constructed entirely from human skin cell lines, which could be applied for in vitro wound-healing assays. Skin equivalents were constructed from human TERT-immortalized keratinocytes and fibroblasts (TERT-HSE) and compared with native skin and primary HSEs. HSEs were characterized by hematoxylin-eosin and immunohistochemical stainings with markers for epidermal proliferation and differentiation, basement membrane (BM), fibroblasts, and the extracellular matrix (ECM). Ultrastructure was determined with electron microscopy. To test the functionality of the TERT-HSE, burn and cold injuries were applied, followed by immunohistochemical stainings, measurement of reepithelialization, and determination of secreted wound-healing mediators. The TERT-HSE was composed of a fully differentiated epidermis and a fibroblast-populated dermis comparable to native skin and primary HSE. The epidermis consisted of proliferating keratinocytes within the basal layer, followed by multiple spinous layers, a granular layer, and cornified layers. Within the TERT-HSE, the membrane junctions such as corneosomes, desmosomes, and hemidesmosomes were well developed as shown by ultrastructure pictures. Furthermore, the BM consisted of a lamina lucida and lamina densa comparable to native skin. The dermal matrix of the TERT-HSE was more similar to native skin than the primary construct, since collagen III, an ECM marker, was present in TERT-HSEs and absent in primary HSEs. After wounding, the TERT-HSE was able to reepithelialize and secrete inflammatory wound-healing mediators. In conclusion, the novel TERT-HSE, constructed entirely

Triolein reduces MMP-1 upregulation in dermal fibroblasts generated by ROS production in UVB-irradiated keratinocytes.

PubMed

Leirós, Gustavo J; Kusinsky, Ana Gabriela; Balañá, María Eugenia; Hagelin, Karin

2017-02-01

Cytokine production and oxidative stress generated by ultraviolet radiation B (UVB) skin exposure are main factors of skin photoaging. Interleukin-6 (IL-6) produced by irradiated keratinocytes is proposed to have a role in metalloproteinases (MMPs) expression activation in dermal fibroblasts. We examined the effect of triolein treatment of UVB-irradiated keratinocytes on MMP1 (interstitial collagenase) expression response of dermal fibroblasts. We assayed UVB-irradiated keratinocytes soluble signals, mainly IL-6 and reactive oxygen species (ROS). IL-6 expression and ROS generation were assayed in UVB-irradiated keratinocytes. MMP1 mRNA expression response was assayed in fibroblasts grown in keratinocytes conditioned medium. We evaluated the effect of treating keratinocytes with triolein on IL-6 expression and ROS generation in keratinocytes, and MMP1 expression in fibroblasts. The irradiation of epidermal cells with sublethal UVB doses increased IL-6 expression and ROS generation. Conditioned culture medium collected from keratinocytes was used to culture dermal fibroblasts. MMP1 mRNA expression increase was observed in fibroblasts cultured in medium collected from UVB-irradiated keratinocytes. Triolein treatment reduced the IL-6 expression and ROS generation in keratinocytes and this effect was reflected in downregulation of MMP1 expression in fibroblasts. Triolein reduces both the expression of IL-6 and ROS generation in irradiated keratinocytes. It seems to exert an anti-inflammatory and anti-oxidative stress effect on irradiated keratinocytes that in turn reduces MMP1 expression in dermal fibroblasts. Collectively, these results indicate that triolein could act as a photoprotective agent. Copyright © 2016 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

Human umbilical vein endothelial cells protect against hypoxic-ischemic damage in neonatal brain via stromal cell-derived factor 1/C-X-C chemokine receptor type 4.

PubMed

Wu, Chia-Ching; Chen, Yi-Chi; Chang, Ying-Chao; Wang, Lan-Wan; Lin, Yung-Chieh; Chiang, Yi-Lun; Ho, Chien-Jung; Huang, Chao-Ching

2013-05-01

Agents that protect against neurovascular damage provide a powerful neuroprotective strategy. Human umbilical vein endothelial cells (HUVECs) may be used to treat neonates with hypoxic-ischemia (HI) because of its autologous capability. We hypothesized that peripherally injected HUVECs entered the brain after HI, protected against neurovascular damage, and provided protection via stromal cell-derived factor 1/C-X-C chemokine receptor type 4 pathway in neonatal brain. Postpartum day 7 rat pups received intraperitoneal injections of low-passage HUVEC-P4, high-passage HUVEC-P8, or conditioned medium before and immediately after HI. HUVECs were transfected with adenovirus-green fluorescent protein for cell tracing. Oxygen-glucose deprivation was established by coculturing HUVEC-P4 with mouse neuroblastoma neuronal cells (Neuro-2a) and with mouse immortalized cerebral vascular endothelial cells (b.End3). HUVEC-P4-treated group had more blood levels of green fluorescent protein-positive cells than HUVEC-P8-treated group 3 hours postinjection. Intraperitoneally injected HUVEC-P4, but not HUVEC-P8, entered the cortex after HI and positioned closed to the neurons and microvessels. Compared with the condition medium-treated group, the HUVEC-P4-treated but not the HUVEC-P8-treated group showed significantly less neuronal apoptosis and blood-brain barrier damage and more preservation of microvessels in the cortex 24 hours after HI. On postpartum day 14, the HUVEC-P4-treated group showed significant neuroprotection compared with the condition medium-treated group. Stromal cell-derived factor 1 was upregulated in the ipsilateral cortex 3 hours after HI, and inhibiting the stromal cell-derived factor 1/C-X-C chemokine receptor type 4 reduced the protective effect of HUVEC-P4. In vitro transwell coculturing of HUVEC-P4 also significantly protected against oxygen-glucose deprivation cell death in neurons and endothelial cells. Cell therapy using HUVECs may provide a powerful

Pulmonary function in microgravity: KC-135 experience

NASA Technical Reports Server (NTRS)

Guy, Harold J.; Prisk, G. K.

1991-01-01

We have commenced a KC-135 program that parallels and proceeds our Spacelab (SLS-1) pulmonary function experiment. Our first task was to elucidate the affect of normal gravitation on the shape of the maximum expiratory flow volume (MEFV) curve. Nine normal subjects performed multiple MEFV maneuvers at 0-G, 1-G, and approximately 1.7-G. The MEFV curves for each subject were filtered, aligned at RV, and ensemble-averaged to produce an average MEFV curve for each state, allowing differences to be studied. Most subjects showed a decrease in the FVC at 0-G, which we attribute to an increased intrathoracic blood volume. In most of these subjects, the mean lung volume associated with a given flow was lower at 0-G, over about the upper half of the vital capacity. This is similar to the change previously reported during heat out immersion and is consistent with the known affect of engorgement of the lung with blood, on elastic recoil. There were also consistent but highly individual changes in the position and magnitude of detailed features of the curve, the individual patterns being similar to those previously reported on transition from the erect to the supine position. This supports the idea that the location and motion of choke points which determine the detailed individual configuration of MEFV curves, can be significantly influenced by gravitational forces, presumably via the effects of change in longitudinal tension on local airway pressure-diameter behavior and wave speed. We have developed a flight mass spectrometer and have commenced a study of single breath gradients in gas exchange, inert gas washouts, and rebreathing cardiac outputs and lung volumes at 0-G, 1-G, and 1.7-G. Comparison of our results with those from SLS-1 should identify the opportunities and limitations of the KC-135 as an accessible microgravity resource.

Human brain metastatic stroma attracts breast cancer cells via chemokines CXCL16 and CXCL12.

PubMed

Chung, Brile; Esmaeili, Ali A; Gopalakrishna-Pillai, Sailesh; Murad, John P; Andersen, Emily S; Kumar Reddy, Naveen; Srinivasan, Gayathri; Armstrong, Brian; Chu, Caleb; Kim, Young; Tong, Tommy; Waisman, James; Yim, John H; Badie, Behnam; Lee, Peter P

2017-01-01

The tumor microenvironment is composed of heterogeneous populations of cells, including cancer, immune, and stromal cells. Progression of tumor growth and initiation of metastasis is critically dependent on the reciprocal interactions between cancer cells and stroma. Through RNA-Seq and protein analyses, we found that cancer-associated fibroblasts derived from human breast cancer brain metastasis express significantly higher levels of chemokines CXCL12 and CXCL16 than fibroblasts from primary breast tumors or normal breast. To further understand the interplay between cancer cells and cancer-associated fibroblasts from each site, we developed three-dimensional organoids composed of patient-derived primary or brain metastasis cancer cells with matching cancer-associated fibroblasts. Three-dimensional CAF aggregates generated from brain metastasis promote migration of cancer cells more effectively than cancer-associated fibroblast aggregates derived from primary tumor or normal breast stromal cells. Treatment with a CXCR4 antagonist and/or CXCL16 neutralizing antibody, alone or in combination, significantly inhibited migration of cancer cells to brain metastatic cancer-associated fibroblast aggregates. These results demonstrate that human brain metastasis cancer-associated fibroblasts potently attract breast cancer cells via chemokines CXCL12 and CXCL16, and blocking CXCR6-CXCL16/CXCR4-CXCL12 receptor-ligand interactions may be an effective therapy for preventing breast cancer brain metastasis.

Hemorrhagic shock shifts the serum cytokine profile from pro- to anti-inflammatory after experimental traumatic brain injury in mice.

PubMed

Shein, Steven L; Shellington, David K; Exo, Jennifer L; Jackson, Travis C; Wisniewski, Stephen R; Jackson, Edwin K; Vagni, Vincent A; Bayır, Hülya; Clark, Robert S B; Dixon, C Edward; Janesko-Feldman, Keri L; Kochanek, Patrick M

2014-08-15

Secondary insults, such as hemorrhagic shock (HS), worsen outcome from traumatic brain injury (TBI). Both TBI and HS modulate levels of inflammatory mediators. We evaluated the addition of HS on the inflammatory response to TBI. Adult male C57BL6J mice were randomized into five groups (n=4 [naïve] or 8/group): naïve; sham; TBI (through mild-to-moderate controlled cortical impact [CCI] at 5 m/sec, 1-mm depth), HS; and CCI+HS. All non-naïve mice underwent identical monitoring and anesthesia. HS and CCI+HS underwent a 35-min period of pressure-controlled hemorrhage (target mean arterial pressure, 25-27 mm Hg) and a 90-min resuscitation with lactated Ringer's injection and autologous blood transfusion. Mice were sacrificed at 2 or 24 h after injury. Levels of 13 cytokines, six chemokines, and three growth factors were measured in serum and in five brain tissue regions. Serum levels of several proinflammatory mediators (eotaxin, interferon-inducible protein 10 [IP-10], keratinocyte chemoattractant [KC], monocyte chemoattractant protein 1 [MCP-1], macrophage inflammatory protein 1alpha [MIP-1α], interleukin [IL]-5, IL-6, tumor necrosis factor alpha, and granulocyte colony-stimulating factor [G-CSF]) were increased after CCI alone. Serum levels of fewer proinflammatory mediators (IL-5, IL-6, regulated upon activation, normal T-cell expressed, and secreted, and G-CSF) were increased after CCI+HS. Serum level of anti-inflammatory IL-10 was significantly increased after CCI+HS versus CCI alone. Brain tissue levels of eotaxin, IP-10, KC, MCP-1, MIP-1α, IL-6, and G-CSF were increased after both CCI and CCI+HS. There were no significant differences between levels after CCI alone and CCI+HS in any mediator. Addition of HS to experimental TBI led to a shift toward an anti-inflammatory serum profile--specifically, a marked increase in IL-10 levels. The brain cytokine and chemokine profile after TBI was minimally affected by the addition of HS.

Primed Mycobacterial Uveitis (PMU): Histologic and Cytokine Characterization of a Model of Uveitis in Rats

PubMed Central

Pepple, Kathryn L.; Rotkis, Lauren; Van Grol, Jennifer; Wilson, Leslie; Sandt, Angela; Lam, Deborah L.; Carlson, Eric; Van Gelder, Russell N.

2015-01-01

Purpose The purpose of this study was to compare the histologic features and cytokine profiles of experimental autoimmune uveitis (EAU) and a primed mycobacterial uveitis (PMU) model in rats. Methods In Lewis rats, EAU was induced by immunization with interphotoreceptor binding protein peptide, and PMU was induced by immunization with a killed mycobacterial extract followed by intravitreal injection of the same extract. Clinical course, histology, and the cytokine profiles of the aqueous and vitreous were compared using multiplex bead fluorescence immunoassays. Results Primed mycobacterial uveitis generates inflammation 2 days after intravitreal injection and resolves spontaneously 14 days later. CD68+ lymphocytes are the predominant infiltrating cells and are found in the anterior chamber, surrounding the ciliary body and in the vitreous. In contrast to EAU, no choroidal infiltration or retinal destruction is noted. At the day of peak inflammation, C-X-C motif ligand 10 (CXCL10), IL-1β, IL-18, and leptin were induced in the aqueous of both models. Interleukin-6 was induced 2-fold in the aqueous of PMU but not EAU. Cytokines elevated in the aqueous of EAU exclusively include regulated on activation, normal T cell expressed and secreted (RANTES), lipopolysaccharide-induced CXC chemokine (LIX), growth-related oncogene/keratinocyte chemokine (GRO/KC), VEGF, monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1α (MIP-1α), and IL-17A. In the vitreous, CXCL10, GRO/KC, RANTES, and MIP-1α were elevated in both models. Interleukin-17A and IL-18 were elevated exclusively in EAU. Conclusions Primed mycobacterial uveitis generates an acute anterior and intermediate uveitis without retinal involvement. Primed mycobacterial uveitis has a distinct proinflammatory cytokine profile compared with EAU, suggesting PMU is a good complementary model for study of immune-mediated uveitis. CXCL10, a proinflammatory cytokine, was increased in the aqueous and

Kansas City Transportation and Local-Scale Air Quality Study (KC-TRAQS) Fact Sheet

EPA Pesticide Factsheets

In fall 2017, the U.S. Environmental Protection Agency (EPA) launched the Kansas City Transportation Local-Scale Air Quality Study (KC-TRAQS) to learn more about local community air quality in three neighborhoods in Kansas City, KS.

Keratinocytes at the uppermost layer of epidermis might act as sensors of atmospheric pressure change.

PubMed

Denda, Mitsuhiro

2016-01-01

It has long been suggested that climate, especially atmospheric pressure change, can cause health problems ranging from migraine to myocardial infarction. Here, I hypothesize that the sensory system of epidermal keratinocytes mediates the influence of atmospheric pressure change on the human physiological condition. We previously demonstrated that even subtle changes of atmospheric pressure (5-20 hPa) induce elevation of intracellular calcium level in cultured human keratinocytes (excitation of keratinocytes). It is also established that communication occurs between epidermal keratinocytes and peripheral nerve systems. Moreover, various neurotransmitters and hormones that influence multiple systems (nervous, cardiovascular, endocrine, and immune systems) are generated and released from epidermal keratinocytes in response to various external stimuli. Thus, I suggest that pathophysiological phenomena induced by atmospheric pressure changes might be triggered by epidermal keratinocytes.

Involvement of pigment globules containing multiple melanosomes in the transfer of melanosomes from melanocytes to keratinocytes

PubMed Central

Niki, Yoko; Yoshida, Masaki; Ito, Masaaki; Akiyama, Kaoru; Kim, Jin-Hwa; Yoon, Tae-Jin; Matsui, Mary S; Yarosh, Daniel B; Ichihashi, Masamitsu

2011-01-01

The mechanism of melanosome transfer from melanocytes to keratinocytes has not been fully clarified. We now show a route of melanosome transfer using co-cultures of normal human melanocytes and keratinocytes. Substantial levels of melanosome transfer were elicited in co-cultures of melanocytes and keratinocytes separated by a microporous membrane filter. The melanocyte dendrites penetrated into the keratinocyte layer through the filter and many pigment globules were observed in keratinocytes. Electron microscopic observations revealed that melanosomes incorporated in keratinocytes were packed in clusters enclosed by a double membrane. Numerous pigment globules budded off from melanocyte dendrites and were released into the culture medium. Those pigment globules were filled with multiple melanosomes and a few mitochondria but no nuclei. When those globules were added to the culture medium of keratinocytes, they were incorporated and showed double membrane-enclosed melano-phagolysosomes consistent with the structures obtained from the co-culture system. In contrast, when individual naked melanosomes isolated from melanocytes were added to keratinocytes, they were also phagocytosed by keratinocytes but were enclosed by a single membrane in a manner distinct from the co-culture system. These results suggest a novel mechanism of melanosome transfer, wherein melanosomes are packed in membrane globules that bud off from melanocyte dendrites, where they are released into the extracellular space and then phagocytosed by keratinocytes. PMID:21686100

Single Low-Dose Radiation Induced Regulation of Keratinocyte Differentiation in Calcium-Induced HaCaT Cells.

PubMed

Hahn, Hyung Jin; Youn, Hae Jeong; Cha, Hwa Jun; Kim, Karam; An, Sungkwan; Ahn, Kyu Joong

2016-08-01

We are continually exposed to low-dose radiation (LDR) in the range 0.1 Gy from natural sources, medical devices, nuclear energy plants, and other industrial sources of ionizing radiation. There are three models for the biological mechanism of LDR: the linear no-threshold model, the hormetic model, and the threshold model. We used keratinocytes as a model system to investigate the molecular genetic effects of LDR on epidermal cell differentiation. To identify keratinocyte differentiation, we performed western blots using a specific antibody for involucrin, which is a precursor protein of the keratinocyte cornified envelope and a marker for keratinocyte terminal differentiation. We also performed quantitative polymerase chain reaction. We examined whether LDR induces changes in involucrin messenger RNA (mRNA) and protein levels in calcium-induced keratinocyte differentiation. Exposure of HaCaT cells to LDR (0.1 Gy) induced p21 expression. p21 is a key regulator that induces growth arrest and represses stemness, which accelerates keratinocyte differentiation. We correlated involucrin expression with keratinocyte differentiation, and examined the effects of LDR on involucrin levels and keratinocyte development. LDR significantly increased involucrin mRNA and protein levels during calcium-induced keratinocyte differentiation. These studies provide new evidence for the biological role of LDR, and identify the potential to utilize LDR to regulate or induce keratinocyte differentiation.

Single Low-Dose Radiation Induced Regulation of Keratinocyte Differentiation in Calcium-Induced HaCaT Cells

PubMed Central

Hahn, Hyung Jin; Youn, Hae Jeong; Cha, Hwa Jun; Kim, Karam; An, Sungkwan

2016-01-01

Background We are continually exposed to low-dose radiation (LDR) in the range 0.1 Gy from natural sources, medical devices, nuclear energy plants, and other industrial sources of ionizing radiation. There are three models for the biological mechanism of LDR: the linear no-threshold model, the hormetic model, and the threshold model. Objective We used keratinocytes as a model system to investigate the molecular genetic effects of LDR on epidermal cell differentiation. Methods To identify keratinocyte differentiation, we performed western blots using a specific antibody for involucrin, which is a precursor protein of the keratinocyte cornified envelope and a marker for keratinocyte terminal differentiation. We also performed quantitative polymerase chain reaction. We examined whether LDR induces changes in involucrin messenger RNA (mRNA) and protein levels in calcium-induced keratinocyte differentiation. Results Exposure of HaCaT cells to LDR (0.1 Gy) induced p21 expression. p21 is a key regulator that induces growth arrest and represses stemness, which accelerates keratinocyte differentiation. We correlated involucrin expression with keratinocyte differentiation, and examined the effects of LDR on involucrin levels and keratinocyte development. LDR significantly increased involucrin mRNA and protein levels during calcium-induced keratinocyte differentiation. Conclusion These studies provide new evidence for the biological role of LDR, and identify the potential to utilize LDR to regulate or induce keratinocyte differentiation. PMID:27489424

Keratinocyte response to immobilized growth factors for enhanced dermal wound healing

NASA Astrophysics Data System (ADS)

Stefonek-Puccinelli, Tracy Jane

Chronic wounds cost billions of dollars per year to treat and wound care is limited to ineffective and/or expensive options. Chronic wounds are characterized by a failure to reepithelialize, as well as deficiencies in growth factors, such as epidermal growth factor (EGF) and insulin-like growth factor-1 (IGF-1), normally present during wound healing. Our system described herein begins to tackle the problems associated with designing bioactive materials for chronic wound healing applications. We show that we can induce accelerated keratinocyte migration with photo-immobilized EGF and further control migration speed through the culture of cells on different types of gradient patterns of EGF. We also successfully immobilized IGF-1 while retaining its bioactivity, and further showed it induces directed keratinocyte migration, although not as potently as immobilized EGF. Potential synergy between co-immobilized IGF-1 and EGF was also investigated, although EGF continued to dominate the cellular response, and no significant increase in cell migration was achieved via the addition of IGF-1 to the system. To further understand cellular response to our immobilized growth factors, we investigated keratinocyte signaling and function in response to changes in EGF presentation. It was found that immobilized and soluble EGF can play different, yet complementary, roles in regulating keratinocyte function. Specifically, keratinocytes responded to immobilized EGF with high EGF receptor (EGFR) activation, accompanied by low proliferation and high migratory activity. In contrast, keratinocytes treated with soluble EGF displayed a highly proliferative, rather than migratory, phenotype. We then transitioned our photo-immobilization techniques to materials that may be more suitable as a wound dressing, such as silk fibroin films. Silk fibroin is a natural fiber with many desirable qualities for a biomaterial including high strength and elasticity, biocompatibility, a beta

The incidence and multiplicity rates of keratinocyte cancers in Australia.

PubMed

Pandeya, Nirmala; Olsen, Catherine M; Whiteman, David C

2017-10-16

To assess the incidence and multiplicity of keratinocyte cancers (basal cell carcinoma [BCC] and squamous cell carcinoma [SCC]) excised in Australia, and to examine variations by age, sex, state, and prior skin cancer history. Analysis of individual-level Medicare data for keratinocyte cancer treatments (identified by eight specific MBS item codes) during 2011-2014. Histological data from the QSkin prospective cohort study were analysed to estimate BCC and SCC incidence. A 10% systematic random sample of all people registered with Medicare during 1997-2014. People aged at least 20 years in 2011 who made at least one claim for any MBS medical service during 2011-2014 (1 704 193 individuals). Age-standardised incidence rates (ASRs) and standardised incidence ratios (SIRs). The person-based incidence of keratinocyte cancer excisions in Australia was 1531 per 100 000 person-years; incidence increased with age, and was higher for men than women (SIR, 1.43; 95% CI, 1.42-1.45). Lesion-based incidence was 3154 per 100 000 person-years. The estimated ASRs for BCC and SCC were 770 per 100 000 and 270 per 100 000 person-years respectively. During 2011-2014, 3.9% of Australians had one keratinocyte cancer excised, 2.7% had more than one excised; 74% of skin cancers were excised from patients who had two or more lesions removed. Multiplicity was strongly correlated with age; most male patients over 70 were treated for multiple lesions. Keratinocyte cancer incidence was eight times as high among people with a prior history of excisions as among those without. The incidence and multiplicity of keratinocyte cancer in Australia are very high, causing a large disease burden that has not previously been quantified.

Shining a Light on Black Holes in Keratinocytes.

PubMed

Bowman, Shanna L; Marks, Michael S

2018-03-01

The mechanisms by which melanins are transferred from melanocytes and stored within keratinocytes to generate skin pigmentation are hotly debated. Correia et al. and Hurbain et al. provide evidence that melanin cores of melanosomes are secreted from melanocytes and taken up and stored within non-degradative membranous organelles in keratinocytes in the basal epidermis of human skin. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Structural basis of ligand interaction with atypical chemokine receptor 3

NASA Astrophysics Data System (ADS)

Gustavsson, Martin; Wang, Liwen; van Gils, Noortje; Stephens, Bryan S.; Zhang, Penglie; Schall, Thomas J.; Yang, Sichun; Abagyan, Ruben; Chance, Mark R.; Kufareva, Irina; Handel, Tracy M.

2017-01-01

Chemokines drive cell migration through their interactions with seven-transmembrane (7TM) chemokine receptors on cell surfaces. The atypical chemokine receptor 3 (ACKR3) binds chemokines CXCL11 and CXCL12 and signals exclusively through β-arrestin-mediated pathways, without activating canonical G-protein signalling. This receptor is upregulated in numerous cancers making it a potential drug target. Here we collected over 100 distinct structural probes from radiolytic footprinting, disulfide trapping, and mutagenesis to map the structures of ACKR3:CXCL12 and ACKR3:small-molecule complexes, including dynamic regions that proved unresolvable by X-ray crystallography in homologous receptors. The data are integrated with molecular modelling to produce complete and cohesive experimentally driven models that confirm and expand on the existing knowledge of the architecture of receptor:chemokine and receptor:small-molecule complexes. Additionally, we detected and characterized ligand-induced conformational changes in the transmembrane and intracellular regions of ACKR3 that elucidate fundamental structural elements of agonism in this atypical receptor.

Essential role of integrin-linked kinase in regulation of phagocytosis in keratinocytes.

PubMed

Sayedyahossein, Samar; Nini, Lylia; Irvine, Timothy S; Dagnino, Lina

2012-10-01

Phagocytic melanosome uptake by epidermal keratinocytes is a central protective mechanism against damage induced by ultraviolet radiation. Phagocytosis requires formation of pseudopodia via actin cytoskeleton rearrangements. Integrin-linked kinase (ILK) is an important modulator of actin cytoskeletal dynamics. We have examined the role of ILK in regulation of phagocytosis, using epidermal keratinocytes isolated from mice with epidermis-restricted Ilk gene inactivation. ILK-deficient cells exhibited severely impaired capacity to engulf fluorescent microspheres in response to stimulation of the keratinocyte growth factor (KGF) receptor or the protease-activated receptor-2. KGF induced ERK phosphorylation in ILK-expressing and ILK-deficient cells, suggesting that ILK is not essential for KGF receptor signaling. In contrast, KGF promoted activation of Rac1 and formation of pseudopodia in ILK-expressing, but not in ILK-deficient cells. Rac1-deficient keratinocytes also showed substantially impaired phagocytic ability, underlining the importance of ILK-dependent Rac1 function for particle engulfment. Finally, cross-modulation of KGF receptors by integrins may be another important element, as integrin β1-deficient keratinocytes also fail to show significant phagocytosis in response to KGF. Thus, we have identified a novel signaling pathway essential for phagocytosis in keratinocytes, which involves ILK-dependent activation of Rac1 in response to KGF, resulting in the formation of pseudopodia and particle uptake.

Modulation of keratinocyte expression of antioxidants by 4-hydroxynonenal, a lipid peroxidation end product

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

Zheng, Ruijin; Heck, Diane E.; Mishin, Vladimir

2014-03-01

4-Hydroxynonenal (4-HNE) is a lipid peroxidation end product generated in response to oxidative stress in the skin. Keratinocytes contain an array of antioxidant enzymes which protect against oxidative stress. In these studies, we characterized 4-HNE-induced changes in antioxidant expression in mouse keratinocytes. Treatment of primary mouse keratinocytes and PAM 212 keratinocytes with 4-HNE increased mRNA expression for heme oxygenase-1 (HO-1), catalase, NADPH:quinone oxidoreductase (NQO1) and glutathione S-transferase (GST) A1-2, GSTA3 and GSTA4. In both cell types, HO-1 was the most sensitive, increasing 86–98 fold within 6 h. Further characterization of the effects of 4-HNE on HO-1 demonstrated concentration- and time-dependentmore » increases in mRNA and protein expression which were maximum after 6 h with 30 μM. 4-HNE stimulated keratinocyte Erk1/2, JNK and p38 MAP kinases, as well as PI3 kinase. Inhibition of these enzymes suppressed 4-HNE-induced HO-1 mRNA and protein expression. 4-HNE also activated Nrf2 by inducing its translocation to the nucleus. 4-HNE was markedly less effective in inducing HO-1 mRNA and protein in keratinocytes from Nrf2 −/− mice, when compared to wild type mice, indicating that Nrf2 also regulates 4-HNE-induced signaling. Western blot analysis of caveolar membrane fractions isolated by sucrose density centrifugation demonstrated that 4-HNE-induced HO-1 is localized in keratinocyte caveolae. Treatment of the cells with methyl-β-cyclodextrin, which disrupts caveolar structure, suppressed 4-HNE-induced HO-1. These findings indicate that 4-HNE modulates expression of antioxidant enzymes in keratinocytes, and that this can occur by different mechanisms. Changes in expression of keratinocyte antioxidants may be important in protecting the skin from oxidative stress. - Highlights: • Lipid peroxidation generates 4-hydroxynonenal, a reactive aldehyde. • 4-HNE induces antioxidant proteins in mouse keratinocytes. • Induction of

Induction of IL-10 gene expression in human keratinocytes by UVB exposure in vivo and in vitro

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

Enk, C.D.; Blauvelt, A.; Katz, S.I.

Numerous studies have demonstrated that ultraviolet B (UVB) irradiation has profound effects on the skin and systemic immune systems. Because many of the effects of UVB result in suppression of contact sensitivity responses and because IL-10 induces a Th2 rather than a Th1 response, we sought to determine whether UVB irradiation induces IL-10 transcription and subsequent protein secretion by human epidermal cells. Skin of nine volunteers was exposed to UVB or sham irradiation, and epidermal cell suspensions were prepared from suction blister roofs 24 h thereafter. mRNA was extracted using oligo dT-coated magnetic beads, and IL-10 cDNA was amplified withmore » a sensitive RT-PCR technique. We found that IL-10 was constitutively expressed by epidermal cells in 5 of 9 volunteers and that IL-10 message was up-regulated by UVB exposure in all experiments. Since epidermis consists of a heterogeneous cell population with distinct cytokine profiles, we determined whether UVB caused enhanced IL-10 transcription and protein secretion in human keratinocyte cultures. In these experiments, IL-10 was constitutively expressed by keratinocytes and UVB up-regulated IL-10 gene expression in a dose-dependent manner 24 h after in vitro irradiation, coinciding with IL-10 protein secretion into the culture supernatants. Taken together, the findings indicate that UVB irradiation induces IL-10 in human keratinocytes and suggest that keratinocyte-derived IL-10 may be an important component of the immunosuppression that results from UVB irradiation. 55 refs., 5 figs.« less

Characterization of a Human Skin Equivalent Model to Study the Effects of Ultraviolet B Radiation on Keratinocytes

PubMed Central

Van Lonkhuyzen, Derek R.; Dawson, Rebecca A.; Kimlin, Michael G.; Upton, Zee

2014-01-01

The incidences of skin cancers resulting from chronic ultraviolet radiation (UVR) exposure are on the incline in both Australia and globally. Hence, the cellular and molecular pathways that are associated with UVR-induced photocarcinogenesis need to be urgently elucidated, in order to develop more robust preventative and treatment strategies against skin cancers. In vitro investigations into the effects of UVR (in particular, the highly mutagenic UVB wavelength) have, to date, mainly involved the use of cell culture and animal models. However, these models possess biological disparities to native skin, which, to some extent, have limited their relevance to the in vivo situation. To address this, we characterized a three-dimensional, tissue-engineered human skin equivalent (HSE) model (consisting of primary human keratinocytes cultured on a dermal-derived scaffold) as a representation of a more physiologically relevant platform to study keratinocyte responses to UVB. Significantly, we demonstrate that this model retains several important epidermal properties of native skin. Moreover, UVB irradiation of the HSE constructs was shown to induce key markers of photodamage in the HSE keratinocytes, including the formation of cyclobutane pyrimidine dimers, the activation of apoptotic pathways, the accumulation of p53, and the secretion of inflammatory cytokines. Importantly, we also demonstrate that the UVB-exposed HSE constructs retain the capacity for epidermal repair and regeneration after photodamage. Together, our results demonstrate the potential of this skin equivalent model as a tool to study various aspects of the acute responses of human keratinocytes to UVB radiation damage. PMID:24219750

Improvement of Human Keratinocyte Migration by a Redox Active Bioelectric Dressing

PubMed Central

Banerjee, Jaideep; Das Ghatak, Piya; Roy, Sashwati; Khanna, Savita; Sequin, Emily K.; Bellman, Karen; Dickinson, Bryan C.; Suri, Prerna; Subramaniam, Vish V.; Chang, Christopher J.; Sen, Chandan K.

2014-01-01

Exogenous application of an electric field can direct cell migration and improve wound healing; however clinical application of the therapy remains elusive due to lack of a suitable device and hence, limitations in understanding the molecular mechanisms. Here we report on a novel FDA approved redox-active Ag/Zn bioelectric dressing (BED) which generates electric fields. To develop a mechanistic understanding of how the BED may potentially influence wound re-epithelialization, we direct emphasis on understanding the influence of BED on human keratinocyte cell migration. Mapping of the electrical field generated by BED led to the observation that BED increases keratinocyte migration by three mechanisms: (i) generating hydrogen peroxide, known to be a potent driver of redox signaling, (ii) phosphorylation of redox-sensitive IGF1R directly implicated in cell migration, and (iii) reduction of protein thiols and increase in integrinαv expression, both of which are known to be drivers of cell migration. BED also increased keratinocyte mitochondrial membrane potential consistent with its ability to fuel an energy demanding migration process. Electric fields generated by a Ag/Zn BED can cross-talk with keratinocytes via redox-dependent processes improving keratinocyte migration, a critical event in wound re-epithelialization. PMID:24595050

Structure-function analysis of the extracellular domains of the Duffy antigen/receptor for chemokines: characterization of antibody and chemokine binding sites.

PubMed

Tournamille, Christophe; Filipe, Anne; Wasniowska, Kazimiera; Gane, Pierre; Lisowska, Elwira; Cartron, Jean-Pierre; Colin, Yves; Le Van Kim, Caroline

2003-09-01

The Duffy antigen/receptor for chemokines (DARC), a seven-transmembrane glycoprotein carrying the Duffy (Fy) blood group, acts as a widely expressed promiscuous chemokine receptor. In a structure-function study, we analysed the binding of chemokines and anti-Fy monoclonal antibodies (mAbs) to K562 cells expressing 39 mutant forms of DARC with alanine substitutions spread out on the four extracellular domains (ECDs). Using synthetic peptides, we defined previously the Fy6 epitope (22-FEDVW-26), and we characterized the Fya epitope as the linear sequence 41-YGANLE-46. In agreement with these results, mutations of F22-E23, V25 and Y41, G42, N44, L45 on ECD1 abolished the binding of anti-Fy6 and anti-Fya mAbs to K562 cells respectively, Anti-Fy3 binding was abolished by D58-D59 (ECD1), R124 (ECD2), D263 and D283 (ECD4) substitutions. Mutations of C51 (ECD1), C129 (ECD2), C195 (ECD3) and C276 (ECD4 severely reduced anti-Fy3 and CXC-chemokine ligand 8 (CXCL-8) binding. CXCL-8 binding was also abrogated by mutations of F22-E23, P50 (ECD1) and D263, R267, D283 (ECD4). These results defined the Fya epitope and suggested that (1) two disulphide bridges are involved in the creation of an active chemokine binding pocket; (2) a limited number of amino acids in ECDs 1-4 participate in CXCL-8 binding; and (3) Fy3 is a conformation-dependent epitope involving all ECDs. We also showed that N-glycosylation of DARC occurred on N16SS and did not influence antibody and chemokine binding.

Defining the chemokine basis for leukocyte recruitment during viral encephalitis.

PubMed

Michlmayr, Daniela; McKimmie, Clive S; Pingen, Marieke; Haxton, Ben; Mansfield, Karen; Johnson, Nicholas; Fooks, Anthony R; Graham, Gerard J

2014-09-01

The encephalitic response to viral infection requires local chemokine production and the ensuing recruitment of immune and inflammatory leukocytes. Accordingly, chemokine receptors present themselves as plausible therapeutic targets for drugs aimed at limiting encephalitic responses. However, it remains unclear which chemokines are central to this process and whether leukocyte recruitment is important for limiting viral proliferation and survival in the brain or whether it is predominantly a driver of coincident inflammatory pathogenesis. Here we examine chemokine expression and leukocyte recruitment in the context of avirulent and virulent Semliki Forest virus (SFV) as well as West Nile virus infection and demonstrate rapid and robust expression of a variety of inflammatory CC and CXC chemokines in all models. On this basis, we define a chemokine axis involved in leukocyte recruitment to the encephalitic brain during SFV infection. CXCR3 is the most active; CCR2 is also active but less so, and CCR5 plays only a modest role in leukocyte recruitment. Importantly, inhibition of each of these receptors individually and the resulting suppression of leukocyte recruitment to the infected brain have no effect on viral titer or survival following infection with a virulent SFV strain. In contrast, simultaneous blockade of CXCR3 and CCR2 results in significantly reduced mortality in response to virulent SFV infection. In summary, therefore, our data provide an unprecedented level of insight into chemokine orchestration of leukocyte recruitment in viral encephalitis. Our data also highlight CXCR3 and CCR2 as possible therapeutic targets for limiting inflammatory damage in response to viral infection of the brain. Brain inflammation (encephalitis) in response to viral infection can lead to severe illness and even death. This therefore represents an important clinical problem and one that requires the development of new therapeutic approaches. Central to the pathogenesis of

Enhanced Chronic Pain Management Utilizing Chemokine Receptor Antagonists

DTIC Science & Technology

2016-08-01

approximately halfway into the solution. All animals were tested at 60, 15 and 0 min before drug injection. For each animal , the first reading was discarded...approval (December 31, 2015), hiring new personnel, conducting baseline testing for procedures not involving animals , testing equipment, developing...treatment; Analgesia; Nociception; Antinociception; Inflammation; Chemokines; Chemokine receptor antagonists; Opioid analgesics; Animal models of pain

Air-Stimulated ATP Release from Keratinocytes Occurs through Connexin Hemichannels

PubMed Central

Barr, Travis P.; Albrecht, Phillip J.; Hou, Quanzhi; Mongin, Alexander A.; Strichartz, Gary R.; Rice, Frank L.

2013-01-01

Cutaneous ATP release plays an important role in both epidermal stratification and chronic pain, but little is known about ATP release mechanisms in keratinocytes that comprise the epidermis. In this study, we analyzed ATP release from cultured human neonatal keratinocytes briefly exposed to air, a process previously demonstrated to trigger ATP release from these cells. We show that exposing keratinocytes to air by removing media for 15 seconds causes a robust, long-lasting ATP release. This air-stimulated ATP release was increased in calcium differentiated cultures which showed a corresponding increase in connexin 43 mRNA, a major component of keratinocyte hemichannels. The known connexin hemichannel inhibitors 1-octanol and carbenoxolone both significantly reduced air-stimulated ATP release, as did two drugs traditionally used as ABC transporter inhibitors (glibenclamide and verapamil). These same 4 inhibitors also prevented an increase in the uptake of a connexin permeable dye induced by air exposure, confirming that connexin hemichannels are open during air-stimulated ATP release. In contrast, activity of the MDR1 ABC transporter was reduced by air exposure and the drugs that inhibited air-stimulated ATP release had differential effects on this transporter. These results indicate that air exposure elicits non-vesicular release of ATP from keratinocytes through connexin hemichannels and that drugs used to target connexin hemichannels and ABC transporters may cross-inhibit. Connexins represent a novel, peripheral target for the treatment of chronic pain and dermatological disease. PMID:23457608

Air-stimulated ATP release from keratinocytes occurs through connexin hemichannels.

PubMed

Barr, Travis P; Albrecht, Phillip J; Hou, Quanzhi; Mongin, Alexander A; Strichartz, Gary R; Rice, Frank L

2013-01-01

Cutaneous ATP release plays an important role in both epidermal stratification and chronic pain, but little is known about ATP release mechanisms in keratinocytes that comprise the epidermis. In this study, we analyzed ATP release from cultured human neonatal keratinocytes briefly exposed to air, a process previously demonstrated to trigger ATP release from these cells. We show that exposing keratinocytes to air by removing media for 15 seconds causes a robust, long-lasting ATP release. This air-stimulated ATP release was increased in calcium differentiated cultures which showed a corresponding increase in connexin 43 mRNA, a major component of keratinocyte hemichannels. The known connexin hemichannel inhibitors 1-octanol and carbenoxolone both significantly reduced air-stimulated ATP release, as did two drugs traditionally used as ABC transporter inhibitors (glibenclamide and verapamil). These same 4 inhibitors also prevented an increase in the uptake of a connexin permeable dye induced by air exposure, confirming that connexin hemichannels are open during air-stimulated ATP release. In contrast, activity of the MDR1 ABC transporter was reduced by air exposure and the drugs that inhibited air-stimulated ATP release had differential effects on this transporter. These results indicate that air exposure elicits non-vesicular release of ATP from keratinocytes through connexin hemichannels and that drugs used to target connexin hemichannels and ABC transporters may cross-inhibit. Connexins represent a novel, peripheral target for the treatment of chronic pain and dermatological disease.

Chemokine programming dendritic cell antigen response: part II - programming antigen presentation to T lymphocytes by partially maintaining immature dendritic cell phenotype.

PubMed

Park, Jaehyung; Bryers, James D

2013-05-01

In a companion article to this study,(1) the successful programming of a JAWSII dendritic cell (DC) line's antigen uptake and processing was demonstrated based on pre-treatment of DCs with a specific 'cocktail' of select chemokines. Chemokine pre-treatment modulated cytokine production before and after DC maturation [by lipopolysaccharide (LPS)]. After DC maturation, it induced an antigen uptake and processing capacity at levels 36% and 82% higher than in immature DCs, respectively. Such programming proffers a potential new approach to enhance vaccine efficiency. Unfortunately, simply enhancing antigen uptake does not guarantee the desired activation and proliferation of lymphocytes, e.g. CD4(+) T cells. In this study, phenotype changes and antigen presentation capacity of chemokine pre-treated murine bone marrow-derived DCs were examined in long-term co-culture with antigen-specific CD4(+) T cells to quantify how chemokine pre-treatment may impact the adaptive immune response. When a model antigen, ovalbumin (OVA), was added after intentional LPS maturation of chemokine-treated DCs, OVA-biased CD4(+) T-cell proliferation was initiated from ~ 100% more undivided naive T cells as compared to DCs treated only with LPS. Secretion of the cytokines interferon-γ, interleukin-1β, interleukin-2 and interleukin-10 in the CD4(+) T cell : DC co-culture (with or without chemokine pre-treatment) were essentially the same. Chemokine programming of DCs with a 7 : 3 ratio of CCL3 : CCL19 followed by LPS treatment maintained partial immature phenotypes of DCs, as indicated by surface marker (CD80 and CD86) expression over time. Results here and in our companion paper suggest that chemokine programming of DCs may provide a novel immunotherapy strategy to obviate the natural endocytosis limit of DC antigen uptake, thus potentially increasing DC-based vaccine efficiency. © 2012 Blackwell Publishing Ltd.

Discontinuous pore fluid distribution under microgravity--KC-135 flight investigations

NASA Technical Reports Server (NTRS)

Reddi, Lakshmi N.; Xiao, Ming; Steinberg, Susan L.

2005-01-01

Designing a reliable plant growth system for crop production in space requires the understanding of pore fluid distribution in porous media under microgravity. The objective of this experimental investigation, which was conducted aboard NASA KC-135 reduced gravity flight, is to study possible particle separation and the distribution of discontinuous wetting fluid in porous media under microgravity. KC-135 aircraft provided gravity conditions of 1, 1.8, and 10(-2) g. Glass beads of a known size distribution were used as porous media; and Hexadecane, a petroleum compound immiscible with and lighter than water, was used as wetting fluid at residual saturation. Nitrogen freezer was used to solidify the discontinuous Hexadecane ganglia in glass beads to preserve the ganglia size changes during different gravity conditions, so that the blob-size distributions (BSDs) could be measured after flight. It was concluded from this study that microgravity has little effect on the size distribution of pore fluid blobs corresponding to residual saturation of wetting fluids in porous media. The blobs showed no noticeable breakup or coalescence during microgravity. However, based on the increase in bulk volume of samples due to particle separation under microgravity, groups of particles, within which pore fluid blobs were encapsulated, appeared to have rearranged themselves under microgravity.

Human plasma platelet-derived exosomes: effects of aspirin.

PubMed

Goetzl, Edward J; Goetzl, Laura; Karliner, Joel S; Tang, Norina; Pulliam, Lynn

2016-05-01

Platelet-derived exosomes mediate platelet atherogenic interactions with endothelial cells and monocytes. A new method for isolation of plasma platelet-derived exosomes is described and used to examine effects of aging and aspirin on exosome cargo proteins. Exosome secretion by purified platelets in vitro did not increase after exposure to thrombin or collagen, as assessed by exosome counts and quantification of the CD81 exosome marker. Thrombin and collagen increased exosome content of α-granule chemokines CXCL4 and CXCL7 and cytoplasmic high-mobility group box 1 (HMGB1) protein, but not membrane platelet glycoprotein VI (GPVI), with dependence on extracellular calcium. Aspirin consumption significantly blocked thrombin- and collagen-induced increases in exosome cargo levels of chemokines and HMGB1, without altering total exosome secretion or GPVI cargo. Plasma platelet-derived exosomes, enriched by absorption with mouse antihuman CD42b [platelet glycoprotein Ib (GPIb)] mAb, had sizes and cargo protein contents similar to those of exosomes from purified platelets. The plasma platelet-derived exosome number is lower and its chemokine and HMGB1 levels higher after age 65 yr. Aspirin consumption significantly suppressed cargo protein levels of plasma platelet-derived exosomes without altering total levels of exosomes. Cargo proteins of human plasma platelet-derived exosomes may biomark platelet abnormalities and in vivo effects of drugs.- Goetzl, E. J., Goetzl, L., Karliner, J. S., Tang, N., Pulliam, L. Human plasma platelet-derived exosomes: effects of aspirin. © FASEB.

Dermoscopy of keratinocyte skin cancer.

PubMed

Kupsa, Romana; Deinlein, Teresa; Woltsche, Nora; Hofmann-Wellenhof, Rainer; Zalaudek, Iris

2016-12-01

Keratinocyte skin cancer (KSC) refers to a broad class of tumors with a regrettably rising incidence worldwide. The term KSC stands for different stages of skin cancer including actinic keratosis (AK), Bowen's Disease (BD) and invasive squamous cell carcinoma (SCC). These tumors tend to grow slow, are unlikely to result in distant metastatic disease and death but they frequently destroy underlying tissues and should therefore be removed at the earliest possible stage. The fact that the cure rate is very high when KSC is detected in early stages emphasizes once more the applicability of dermoscopy as an integrative part of the clinical examination of skin tumors. In the first part of this review article, we summarize key points of the dermoscopic diagnosis of KSC including different stages of AK, BD and SCC. In the second part we want to focus on the progression model of KSC and the role of dermoscopy in the management of keratinocyte skin cancer.

Epidermal keratinocytes initiate wound healing and pro-inflammatory immune responses following percutaneous schistosome infection

PubMed Central

Bourke, Claire D.; Prendergast, Catriona T.; Sanin, David E.; Oulton, Tate E.; Hall, Rebecca J.; Mountford, Adrian P.

2015-01-01

Keratinocytes constitute the majority of cells in the skin’s epidermis, the first line of defence against percutaneous pathogens. Schistosome larvae (cercariae) actively penetrate the epidermis to establish infection, however the response of keratinocytes to invading cercariae has not been investigated. Here we address the hypothesis that cercariae activate epidermal keratinocytes to promote the development of a pro-inflammatory immune response in the skin. C57BL/6 mice were exposed to Schistosoma mansoni cercariae via each pinna and non-haematopoietic cells isolated from epidermal tissue were characterised for the presence of different keratinocyte sub-sets at 6, 24 and 96 h p.i. We identified an expansion of epidermal keratinocyte precursors (CD45−, CD326−, CD34+) within 24 h of infection relative to naïve animals. Following infection, cells within the precursor population displayed a more differentiated phenotype (α6integrin−) than in uninfected skin. Parallel immunohistochemical analysis of pinnae cryosections showed that this expansion corresponded to an increase in the intensity of CD34 staining, specifically in the basal bulge region of hair follicles of infected mice, and a higher frequency of keratinocyte Ki67+ nuclei in both the hair follicle and interfollicular epidermis. Expression of pro-inflammatory cytokine and stress-associated keratin 6b genes was also transiently upregulated in the epidermal tissue of infected mice. In vitro exposure of keratinocyte precursors isolated from neonatal mouse skin to excretory/secretory antigens released by penetrating cercariae elicited IL-1α and IL-1β production, supporting a role for keratinocyte precursors in initiating cutaneous inflammatory immune responses. Together, these observations indicate that S.mansoni cercariae and their excretory/secretory products act directly upon epidermal keratinocytes, which respond by initiating barrier repair and pro-inflammatory mechanisms similar to those

Fetal Fibroblasts and Keratinocytes with Immunosuppressive Properties for Allogeneic Cell-Based Wound Therapy

PubMed Central

Zuliani, Thomas; Saiagh, Soraya; Knol, Anne-Chantal; Esbelin, Julie; Dréno, Brigitte

2013-01-01

Fetal skin heals rapidly without scar formation early in gestation, conferring to fetal skin cells a high and unique potential for tissue regeneration and scar management. In this study, we investigated the possibility of using fetal fibroblasts and keratinocytes to stimulate wound repair and regeneration for further allogeneic cell-based therapy development. From a single fetal skin sample, two clinical batches of keratinocytes and fibroblasts were manufactured and characterized. Tolerogenic properties of the fetal cells were investigated by allogeneic PBMC proliferation tests. In addition, the potential advantage of fibroblasts/keratinocytes co-application for wound healing stimulation has been examined in co-culture experiments with in vitro scratch assays and a multiplex cytokines array system. Based on keratin 14 and prolyl-4-hydroxylase expression analyses, purity of both clinical batches was found to be above 98% and neither melanocytes nor Langerhans cells could be detected. Both cell types demonstrated strong immunosuppressive properties as shown by the dramatic decrease in allogeneic PBMC proliferation when co-cultured with fibroblasts and/or keratinocytes. We further showed that the indoleamine 2,3 dioxygenase (IDO) activity is required for the immunoregulatory activity of fetal skin cells. Co-cultures experiments have also revealed that fibroblasts-keratinocytes interactions strongly enhanced fetal cells secretion of HGF, GM-CSF, IL-8 and to a lesser extent VEGF-A. Accordingly, in the in vitro scratch assays the fetal fibroblasts and keratinocytes co-culture accelerated the scratch closure compared to fibroblast or keratinocyte mono-cultures. In conclusion, our data suggest that the combination of fetal keratinocytes and fibroblasts could be of particular interest for the development of a new allogeneic skin substitute with immunomodulatory activity, acting as a reservoir for wound healing growth factors. PMID:23894651

An Evaluation of Lysyl Oxidase–Derived Cross-Linking in Keratoconus by Liquid Chromatography/Mass Spectrometry

PubMed Central

Takaoka, Anna; Babar, Natasha; Hogan, Julia; Kim, MiJung; Price, Marianne O.; Price, Francis W.; Trokel, Stephen L.; Paik, David C.

2016-01-01

Purpose Current literature contains scant information regarding the extent of enzymatic collagen cross-linking in the keratoconus (KC) cornea. The aim of the present study was to examine levels of enzymatic lysyl oxidase–derived cross-links in stromal collagen in KC tissue, and to correlate the cross-link levels with collagen fibril stability as determined by thermal denaturation temperature (Tm). Methods Surgical KC samples (n = 17) and Eye-Bank control (n = 11) corneas of age 18 to 68 years were analyzed. The samples were defatted, reduced (NaBH4), hydrolyzed (6N HCl at 110°C for 18 hours), and cellulose enriched before analysis by C8 high-performance liquid chromatography equipped with parallel fluorescent and mass detectors in selective ion monitoring mode (20 mM heptafluorobutyric acid/methanol 70:30 isocratic at 1 mL/min). Nine different cross-links were measured, and the cross-link density was determined relative to collagen content (determined colorimetrically). The Tm was determined by differential scanning calorimetry. Results Cross-links detected were dihydroxylysinonorleucine (DHLNL), hydroxylysinonorleucine, lysinonorleucine (LNL), and histidinohydroxylysinonorleucine in both control and KC samples. Higher DHLNL levels were detected in KC, whereas the dominant cross-link, LNL, was decreased in KC samples. Decreased LNL levels were observed among KC ≤ 40 corneas. There was no difference in total cross-link density between KC samples and the controls. Pyridinolines, desmosines, and pentosidine were not detected. There was no notable correlation between cross-link levels with fibril instability as determined by Tm. Conclusions Lower levels of LNL in the KC cornea suggest that there might be a cross-linking defect either in fibrillar collagen or the microfibrillar elastic network composed of fibrillin. PMID:26780316

Pyridine-2,6-Bis(Thiocarboxylic Acid) Produced by Pseudomonas stutzeri KC Reduces and Precipitates Selenium and Tellurium Oxyanions

PubMed Central

Zawadzka, Anna M.; Crawford, Ronald L.; Paszczynski, Andrzej J.

2006-01-01

The siderophore of Pseudomonas stutzeri KC, pyridine-2,6-bis(thiocarboxylic acid) (pdtc), is shown to detoxify selenium and tellurium oxyanions in bacterial cultures. A mechanism for pdtc's detoxification of tellurite and selenite is proposed. The mechanism is based upon determination using mass spectrometry and energy-dispersive X-ray spectrometry of the chemical structures of compounds formed during initial reactions of tellurite and selenite with pdtc. Selenite and tellurite are reduced by pdtc or its hydrolysis product H2S, forming zero-valent pdtc selenides and pdtc tellurides that precipitate from solution. These insoluble compounds then hydrolyze, releasing nanometer-sized particles of elemental selenium or tellurium. Electron microscopy studies showed both extracellular precipitation and internal deposition of these metalloids by bacterial cells. The precipitates formed with synthetic pdtc were similar to those formed in pdtc-producing cultures of P. stutzeri KC. Culture filtrates of P. stutzeri KC containing pdtc were also active in removing selenite and precipitating elemental selenium and tellurium. The pdtc-producing wild-type strain KC conferred higher tolerance against selenite and tellurite toxicity than a pdtc-negative mutant strain, CTN1. These observations support the hypothesis that pdtc not only functions as a siderophore but also is involved in an initial line of defense against toxicity from various metals and metalloids. PMID:16672449

S100 chemokines mediate bookmarking of premetastatic niches

PubMed Central

Rafii, Shahin; Lyden, David

2010-01-01

Primary tumours release soluble factors, including VEGF-A, TGFβ and TNFα, which induce expression of the chemokines S100A8 and S100A9 in the myeloid and endothelial cells within the lung before tumour metastasis. These chemokine-activated premetastatic niches support adhesion and invasion of disseminating malignant cells, thereby establishing a fertile habitat for metastatic tumours. PMID:17139281

Specific TRPC6 Channel Activation, a Novel Approach to Stimulate Keratinocyte Differentiation*S⃞

PubMed Central

Müller, Margarethe; Essin, Kirill; Hill, Kerstin; Beschmann, Heike; Rubant, Simone; Schempp, Christoph M.; Gollasch, Maik; Boehncke, W. Henning; Harteneck, Christian; Müller, Walter E.; Leuner, Kristina

2008-01-01

The protective epithelial barrier in our skin undergoes constant regulation, whereby the balance between differentiation and proliferation of keratinocytes plays a major role. Impaired keratinocyte differentiation and proliferation are key elements in the pathophysiology of several important dermatological diseases, including atopic dermatitis and psoriasis. Ca2+ influx plays an essential role in this process presumably mediated by different transient receptor potential (TRP) channels. However, investigating their individual role was hampered by the lack of specific stimulators or inhibitors. Because we have recently identified hyperforin as a specific TRPC6 activator, we investigated the contribution of TRPC6 to keratinocyte differentiation and proliferation. Like the endogenous differentiation stimulus high extracellular Ca2+ concentration ([Ca2+]o), hyperforin triggers differentiation in HaCaT cells and in primary cultures of human keratinocytes by inducing Ca2+ influx via TRPC6 channels and additional inhibition of proliferation. Knocking down TRPC6 channels prevents the induction of Ca2+- and hyperforin-induced differentiation. Importantly, TRPC6 activation is sufficient to induce keratinocyte differentiation similar to the physiological stimulus [Ca2+]o. Therefore, TRPC6 activation by hyperforin may represent a new innovative therapeutic strategy in skin disorders characterized by altered keratinocyte differentiation. PMID:18818211

Structural basis of ligand interaction with atypical chemokine receptor 3

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

Gustavsson, Martin; Wang, Liwen; van Gils, Noortje

2017-01-18

Chemokines drive cell migration through their interactions with seven-transmembrane (7TM) chemokine receptors on cell surfaces. The atypical chemokine receptor 3 (ACKR3) binds chemokines CXCL11 and CXCL12 and signals exclusively through β-arrestin-mediated pathways, without activating canonical G-protein signalling. This receptor is upregulated in numerous cancers making it a potential drug target. Here we collected over 100 distinct structural probes from radiolytic footprinting, disulfide trapping, and mutagenesis to map the structures of ACKR3:CXCL12 and ACKR3:small-molecule complexes, including dynamic regions that proved unresolvable by X-ray crystallography in homologous receptors. The data are integrated with molecular modelling to produce complete and cohesive experimentally drivenmore » models that confirm and expand on the existing knowledge of the architecture of receptor:chemokine and receptor:small-molecule complexes. Additionally, we detected and characterized ligand-induced conformational changes in the transmembrane and intracellular regions of ACKR3 that elucidate fundamental structural elements of agonism in this atypical receptor.« less

An initial investigation into endothelial CC chemokine expression in the human rheumatoid synovium.

PubMed

Rump, Lisa; Mattey, Derek L; Kehoe, Oksana; Middleton, Jim

2017-09-01

Rheumatoid arthritis (RA) is a destructive and chronic autoimmune inflammatory disease. Synovial inflammation is a major feature of RA and is associated with leukocyte recruitment. Leukocytes cross the endothelial cells (ECs) into the synovial tissue and fluid and this migration is mediated via a range of chemokines and adhesion molecules on the ECs. As important mediators of leukocyte extravasation, a number of chemokines from each of the chemokine families have been established as expressed in the RA joint. However, as little information is available on which chemokines are expressed/presented by the ECs themselves, the purpose of the study was to ascertain which of the CC chemokines were localised in RA ECs. Immunofluoresence was used to assess the presence of the CC-family chemokines in RA synovial ECs using von-Willebrand factor (VWF) as a pan-endothelial marker and a range of human chemokine antibodies. The percentage of VWF positive vessels which were positive for the chemokines was determined. The presence of the four most highly expressed novel chemokines were further investigated in non-RA synovial ECs and the sera and synovial fluid (SF) from patients with RA and osteoarthritis (OA). Statistical analysis of immunofluorescence data was carried out by Student's t-test. For analysis of ELISA data, Kruskal-Wallis ANOVA followed by Dunn's multiple comparison test was utilised to analyse differences in sera and SF levels for each chemokine between RA and OA. Spearman rank correlations of sera and SF chemokine levels with a range of clinical variables were also performed. Chemokine detection varied, the least abundant being CCL27 which was present in 8.3% of RA blood vessels and the most abundant being CCL19 which was present in 80%. Of the 26 chemokines studied, 19 have not been previously observed in RA ECs. Four of these novel chemokines, namely CCL7, CCL14, CCL16 and CCL22 were present on ≥60% of vessels. CCL14 and CCL22 were shown to be increased in RA

Vitamin D signaling regulates oral keratinocyte proliferation in vitro and in vivo

PubMed Central

YUAN, FENG-NING F.; VALIYAPARAMBIL, JAYASANKER; WOODS, MICHAEL C.; TRAN, HUY; PANT, RIMA; ADAMS, JOHN S.; MALLYA, SANJAY M.

2014-01-01

The secosteroidal hormone 1,25-dihyroxyvitamin D [1,25(OH)2D3] and its receptor, the vitamin D receptor (VDR), are crucial regulators of epidermal proliferation and differentiation. However, the effects of 1,25(OH)2D3-directed signaling on oral keratinocyte pathophysiology have not been well studied. We examined the role of 1,25(OH)2D3 in regulating proliferation and differentiation in cultured oral keratinocytes and on the oral epithelium in vivo. Using lentiviral-mediated shRNA to silence VDR, we generated an oral keratinocyte cell line with stable knockdown of VDR expression. VDR knockdown significantly enhanced proliferation and disrupted calcium- and 1,25(OH)2D3-induced oral keratinocyte differentiation, emphasizing the anti-proliferative and pro-differentiation effects of 1,25(OH)2D3 in oral keratinocytes. Using vitamin D3-deficient diets, we induced chronic vitamin D deficiency in mice as evidenced by decreased serum 25-hydroxyvitamin D (25OHD) concentrations. The vitamin D-deficient mice manifested increased proliferation of the tongue epithelium, but did not develop any morphological or histological abnormalities in the oral epithelium, suggesting that vitamin D deficiency alone is insufficient to alter oral epithelial homeostasis and provoke carcinogenesis. Immunohistochemical analyses of human and murine oral squamous cell carcinomas showed increased VDR expression. Overall, our results provide strong support for a crucial role for vitamin D signaling in oral keratinocyte pathophysiology. PMID:24626468

The protective effects of piceatannol from passion fruit (Passiflora edulis) seeds in UVB-irradiated keratinocytes.

PubMed

Maruki-Uchida, Hiroko; Kurita, Ikuko; Sugiyama, Kenkichi; Sai, Masahiko; Maeda, Kazuhisa; Ito, Tatsuhiko

2013-01-01

The use of naturally occurring botanicals with substantial antioxidant activity to prevent photoageing is receiving increasing attention. We have previously identified piceatannol and scirpusin B, which is a dimer of piceatannol, as strong antioxidants that are present in passion fruit (Passiflora edulis) seeds. In the present study, the effects of passion fruit seed extract, piceatannol, and scirpusin B on human keratinocytes were investigated. The passion fruit seed extract and piceatannol upregulated the glutathione (GSH) levels in keratinocytes in a dose-dependent manner, indicating that piceatannol is an active component of the passion fruit seed extract in keratinocytes. The pretreatment with piceatannol also suppressed the UVB-induced generation of reactive oxygen species (ROS) in the keratinocytes. In addition, the transfer of the medium from the UVB-irradiated keratinocytes to non-irradiated fibroblasts enhanced matrix-metalloproteinase (MMP)-1 activity, and this MMP-1 induction was reduced when the keratinocytes were pretreated with piceatannol. These results suggest that piceatannol attenuates the UVB-induced activity of MMP-1 along with a reduction of ROS generation in keratinocytes. Thus, piceatannol and passion fruit seed extract containing high amounts of piceatannol are potential anti-photoageing cosmetic ingredients.

Changes in nuclear morphology and chromatin texture of basal keratinocytes in melasma.

PubMed

Brianezi, G; Handel, A C; Schmitt, J V; Miot, L D B; Miot, H A

2015-04-01

The pathogenesis of melasma and the role of keratinocytes in disease development and maintenance are not completely understood. Dermal abnormalities, the expression of inflammatory mediators, growth factors, epithelial expression of melanocortin and sexual hormones receptors suggest that not only melanocytes, but entire epidermal melanin unit is involved in melasma physiopathology. To compare nuclear morphological features and chromatin texture between basal keratinocytes in facial melasma and adjacent normal skin. We took facial skin biopsies (2 mm melasma and adjacent normal skin) from women processed for haematoxylin and eosin. Thirty non-overlapping basal keratinocyte nuclei were segmented and descriptors of area, highest diameter, perimeter, circularity, pixel intensity, profilometric index (Ra) and fractal dimension were extracted using ImageJ software. Basal keratinocyte nuclei from facial melasma epidermis displayed larger size, irregular shape, hyperpigmentation and chromatin heterogeneity by fractal dimension than perilesional skin. Basal keratinocytes from facial melasma display changes in nuclear form and chromatin texture, suggesting that the phenotype differences between melasma and adjacent facial skin can result from complete epidermal melanin unit alterations, not just hypertrophic melanocytes. © 2014 European Academy of Dermatology and Venereology.

Angiodrastic Chemokines in Colorectal Cancer: Clinicopathological Correlations.

PubMed

Emmanouil, George; Ayiomamitis, George; Zizi-Sermpetzoglou, Adamantia; Tzardi, Maria; Moursellas, Andrew; Voumvouraki, Argyro; Kouroumalis, Elias

2018-01-01

To study the expression of angiodrastic chemokines in colorectal tumors and correlate findings with clinicopathological parameters and survival. The proangiogenic factor VEGF, the angiogenic chemokines CXCL8 and CXCL6, and the angiostatic chemokine CXCL4 were measured by ELISA in tumor and normal tissue of 35 stage II and III patients and correlated with the histopathology markers Ki67, p53, p21, bcl2, EGFR, and MLH1 and 5-year survival. The Wilcoxon and chi-square tests were used for statistical comparisons. There was a significant increase of CXCL6 ( p = 0.005) and VEGF ( p = 0.003) in cancerous tissue compared to normal. Patients with lower levels of CXCL8 and CXCL4 lived significantly longer. Patients with loss of EGFR expression had higher levels of CXCL8 while p21 loss was associated with higher levels of CXCL6. Chemokine levels were not correlated with TNM or Dukes classification. Strong expression of p53 was accompanied by decreased survival. (1) The angiogenic factors CXCL6 and VEGF are increased in colorectal cancer tissue with no association with the clinical stage of the disease or survival. (2) However, increased levels of tissue CXCL8 and CXCL4 are associated with poor survival. (3) Strong expression of p53 is found in patients with poor survival.

Candida albicans-induced inflammatory response in human keratinocytes.

PubMed

Wollina, U; Künkel, W; Bulling, L; Fünfstück, C; Knöll, B; Vennewald, I; Hipler, U-C

2004-06-01

Candida albicans strains 3153a, ATCC 48867, CBS 2730, DSM 70014, and Vir 13 were cultivated and sterile C. albicans filtrates were produced. The interaction of soluble Candida factors of these infiltrates with human HaCaT keratinocytes was assayed in vitro. The following parameters were analyzed: cell proliferation, protein synthesis, nuclear matrix protein (NMP) 41 release, cytokine release (IL-1beta, soluble IL-2 receptor, IL-6, and IL-8), and reactive oxygen species (ROS). Cell counts at 1, 12, and 24 h were significantly lower for C. albicans strains CBS 2730 and VIR 13 (P < 0.05). There was no significant change for the remaining strains. Neither the protein synthesis nor the NMP-41 release was significantly affected. IL-6 and IL-8 were stimulated by C. albicans filtrates to different amounts with higher levels in strains of low virulence. There was no effect on the other cytokines. The production of ROS by HaCaT keratinocytes was suppressed. The induction of an inflammatory keratinocyte response by soluble C. albicans factors may play a role among the host-yeast interactions.

[Cultivated keratinocytes on micro-carriers: in vitro studies of a new carrier system].

PubMed

Hecht, J; Hoefter, E A; Hecht, J; Haraida, S; Nerlich, A; Hartinger, A; Mühlbauer, W; Dimoudis, N

1997-03-01

Epidermal grafts from confluently cultivated keratinocytes have been used since the early eighties for the treatment of severe burns, where the shortage of donor sites for split-thickness skin grafts did not allow for adequate wound coverage. The difficult handling of these grafts as well as the advanced differentiation of their epithelial cells into a multilayer sheet poses a problem for their clinical application. The aim of the study was to characterize cultivated keratinocytes, as well as to observe their migration and proliferation from the MC onto a surface. Keratinocytes were isolated from human foreskin and cultivated in serum-free and serum-containing medium according to a modified method by Rheinwald and Green. Collagen-coated Dextran beads were used as MC. The MC were colonized with keratinocytes using the Spinner culture technique. After seeding the colonized MC into culture flasks, their migration and proliferation was monitored regularly through immunohistochemical studies and measurement of the metabolic cell activity. Immunohistological staining proved that the cells isolated from human foreskin represent keratinocytes of the basal type. Keratinocytes, cultivated with serum-containing and serum free medium, both adhered to the surface of the MC, then migrated onto the surface of the flasks and proliferated to form a multilayer of epithelial cells. In the long-term, a flexible epithelial graft consisting of poorly differentiated keratinocytes should be available, which is simple to produce and easy to handle. This would be an alternative method for treating wounds, where the conventional multilayer epithelial graft (ET) is insufficient.

Mu-opiate receptor and Beta-endorphin expression in nerve endings and keratinocytes in human skin.

PubMed

Bigliardi-Qi, M; Sumanovski, L T; Büchner, S; Rufli, T; Bigliardi, P L

2004-01-01

We have previously shown that human epidermal keratinocytes express a functionally active micro-opiate receptor, which adds a new dimension to the recently developed research in neuroimmunodermatology and neurogenic inflammation in skin diseases. Human keratinocytes specifically bind and also produce beta-endorphin, the endogenous micro-opiate receptor ligand. Using confocal imaging microscopy, we could now demonstrate that micro-opiate receptors are not only expressed in keratinocytes, but also on unmyelinated peripheral nerve fibers in the dermis and epidermis. Some of the peripheral nerve fibers also express the ligand beta-endorphin. The keratinocytes positive for beta-endorphin staining are clustered around the terminal ends of the unmyelinated nerve fibers. Therefore the opiate receptor system seems to be crucial in the direct communication between nerves and skin. The keratinocytes can influence the unmyelinated nerve fibers in the epidermis directly via secreting beta-endorphin. On the other hand, nerve fibers can also secrete beta-endorphin and influence the migration, differentiation and probably also the cytokine production pattern of keratinocytes.

CC-chemokine class inhibition attenuates pathological angiogenesis while preserving physiological angiogenesis.

PubMed

Ridiandries, Anisyah; Tan, Joanne T M; Ravindran, Dhanya; Williams, Helen; Medbury, Heather J; Lindsay, Laura; Hawkins, Clare; Prosser, Hamish C G; Bursill, Christina A

2017-03-01

Increasing evidence shows that CC-chemokines promote inflammatory-driven angiogenesis, with little to no effect on hypoxia-mediated angiogenesis. Inhibition of the CC-chemokine class may therefore affect angiogenesis differently depending on the pathophysiological context. We compared the effect of CC-chemokine inhibition in inflammatory and physiological conditions. In vitro , the broad-spectrum CC-chemokine inhibitor "35K" inhibited inflammatory-induced endothelial cell proliferation, migration, and tubulogenesis, with more modest effects in hypoxia. In vivo , adenoviruses were used to overexpress 35K (Ad35K) and GFP (AdGFP, control virus). Plasma chemokine activity was suppressed by Ad35K in both models. In the periarterial femoral cuff model of inflammatory-driven angiogenesis, overexpression of 35K inhibited adventitial neovessel formation compared with control AdGFP-infused mice. In contrast, 35K preserved neovascularization in the hindlimb ischemia model and had no effect on physiological neovascularization in the chick chorioallantoic membrane assay. Mechanistically, 2 key angiogenic proteins (VEGF and hypoxia-inducible factor-1α) were conditionally regulated by 35K, such that expression was inhibited in inflammation but was unchanged in hypoxia. In conclusion, CC-chemokine inhibition by 35K suppresses inflammatory-driven angiogenesis while preserving physiological ischemia-mediated angiogenesis via conditional regulation of VEGF and hypoxia-inducible factor-1α. CC-chemokine inhibition may be an alternative therapeutic strategy for suppressing diseases associated with inflammatory angiogenesis without inducing the side effects caused by global inhibition.- Ridiandries, A., Tan, J. T. M., Ravindran, D., Williams, H., Medbury, H. J., Lindsay, L., Hawkins, C., Prosser, H. C. G., Bursill, C. A. CC-chemokine class inhibition attenuates pathological angiogenesis while preserving physiological angiogenesis. © FASEB.

New paradigms in chemokine receptor signal transduction: Moving beyond the two-site model.

PubMed

Kleist, Andrew B; Getschman, Anthony E; Ziarek, Joshua J; Nevins, Amanda M; Gauthier, Pierre-Arnaud; Chevigné, Andy; Szpakowska, Martyna; Volkman, Brian F

2016-08-15

Chemokine receptor (CKR) signaling forms the basis of essential immune cellular functions, and dysregulated CKR signaling underpins numerous disease processes of the immune system and beyond. CKRs, which belong to the seven transmembrane domain receptor (7TMR) superfamily, initiate signaling upon binding of endogenous, secreted chemokine ligands. Chemokine-CKR interactions are traditionally described by a two-step/two-site mechanism, in which the CKR N-terminus recognizes the chemokine globular core (i.e. site 1 interaction), followed by activation when the unstructured chemokine N-terminus is inserted into the receptor TM bundle (i.e. site 2 interaction). Several recent studies challenge the structural independence of sites 1 and 2 by demonstrating physical and allosteric links between these supposedly separate sites. Others contest the functional independence of these sites, identifying nuanced roles for site 1 and other interactions in CKR activation. These developments emerge within a rapidly changing landscape in which CKR signaling is influenced by receptor PTMs, chemokine and CKR dimerization, and endogenous non-chemokine ligands. Simultaneous advances in the structural and functional characterization of 7TMR biased signaling have altered how we understand promiscuous chemokine-CKR interactions. In this review, we explore new paradigms in CKR signal transduction by considering studies that depict a more intricate architecture governing the consequences of chemokine-CKR interactions. Published by Elsevier Inc.

Evidence for chemokine synergy during neutrophil migration in ARDS

PubMed Central

Williams, Andrew E; José, Ricardo J; Mercer, Paul F; Brealey, David; Parekh, Dhruv; Thickett, David R; O'Kane, Cecelia; McAuley, Danny F; Chambers, Rachel C

2017-01-01

Background Acute respiratory distress syndrome (ARDS) is a life-threatening condition characterised by pulmonary oedema, respiratory failure and severe inflammation. ARDS is further characterised by the recruitment of neutrophils into the lung interstitium and alveolar space. Objectives The factors that regulate neutrophil infiltration into the inflamed lung and our understanding of the pathomechanisms in ARDS remain incomplete. This study aimed at determining the role of the chemokine (C-C motif) ligand (CCL)2 and CCL7 in ARDS. Methods CCL2 and CCL7 protein levels were measured in bronchoalveolar lavage (BAL) fluid obtained from lipopolysaccharide(LPS)-challenged human volunteers and two separate cohorts of patients with ARDS. Neutrophil chemotaxis to ARDS BAL fluid was evaluated and the contribution of each was assessed and compared with chemokine (C-X-C motif) ligand 8 (CXCL8). Chemokine receptor expression on neutrophils from blood or BAL fluid of patients with ARDS was analysed by flow cytometry. Results CCL2 and CCL7 were significantly elevated in BAL fluid recovered from LPS-challenged volunteers and patients with ARDS. BAL fluid from patients with ARDS was highly chemotactic for human neutrophils and neutralising either CCL2 or CCL7 attenuated the neutrophil chemotactic response. Moreover, CCL2 and CCL7 synergised with CXCL8 to promote neutrophil migration. Furthermore, neutrophils isolated from the blood or BAL fluid differentially regulated the cell surface expression of chemokine (C-X-C motif) receptor 1 and C-C chemokine receptor type 2 during ARDS. Conclusion This study highlights important inflammatory chemokines involved in regulating neutrophil migration, which may have potential value as therapeutic targets for the treatment of ARDS. PMID:27496101

Investigation of mitomycin-C-treated fibroblasts in 3-D collagen gel and conditioned medium for keratinocyte proliferation.

PubMed

Huang, Yi-Chau; Wang, Tzu-Wei; Sun, Jui-Sheng; Lin, Feng-Huei

2006-03-01

Fibroblasts produce a spectrum of necessary growth factors essential for growth and proliferation of a variety of cell types. In this study, the paracrine effect of mitomycin-C-treated fibroblasts with various densities in collagen gel for keratinocyte proliferation was investigated from which an optimum cell density and optimum conditioned medium would be determined to expand keratinocyte without further differentiation for skin equivalent tissue engineering. The optimum cell density in collagen feeder gel for optimum collected medium preparation will be determined by checking the level of keratinocyte growth factor and granulocyte macrophage colony-stimulating factor in conventional medium. The results showed that the cell density of 1 x 10(5) cells/gel in the feeder gel is better to produce optimum collected medium. The conditioned medium is prepared by mixing together the optimum collected medium and molecular cellular and developmental biology (MCDB) 153 medium in different ratios for keratinocyte growth. The keratinocyte viability will be measured by 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay to determine the optimum conditioned medium. From the study, 67% conditioned medium was supposed as the better medium for keratinocyte proliferation. In this experiment, the optimum cell density in feeder gel to coculture with keratinocytes is also determined as 1 x 10(5) cells/gel. Keratin 10 (K10) and Terminal Deoxynucleotidyl Transferase Mediated dUTP Nick End Labeling stain will be used to check the cell differentiation and apoptosis, respectively. The results suggest that keratinocytes should not be cultured in postconfluent conditions due to undesired apoptosis and differentiation. The result of cell viability from passages to passages shows that the optimum feeder gel plays a more important role to the keratinocyte proliferation than that of optimum conditioned medium. Keratinocytes cultured with optimum feeder gel in 67% conditioned

In vitro co-culture of human skin keratinocytes and fibroblasts on a biocompatible and biodegradable scaffold.

PubMed

Pajoum Shariati, Seyed Ramin; Shokrgozar, Mohammad Ali; Vossoughi, Manouchehr; Eslamifar, Ali

2009-07-01

Extensive full-thickness burns require replacement of both epidermis and dermis. In designing skin replacements, the goal has been to re-create this model and make a product which has both essential components. In the present study, we developed procedures for establishing confluent, stratified layers of cultured human keratinocytes on the surface of modified collagen-chitosan scaffold that contains fibroblasts. The culture methods for propagation of keratinocytes and fibroblasts isolated from human neonatal foreskin were developed. The growth and proliferation of normal human keratinocytes were evaluated in serum-free (keratinocyte growth medium) and our modified medium. Characterization of human keratinocytes was determined by using pan-keratin and anti-involucrin monoclonal antibodies. For fabrication of relevant biodegradable and biocompatible collagen-chitosan porous scaffold with improved biostability, modified method of freeze-gelation was used. In generating organotypic co-cultures, epidermal keratinocytes were plated onto the upper surface of scaffold containing embedded fibroblasts. The results showed that the growth of isolated human skin fibroblasts and keratinocytes in our modified medium was more than that in the serum-free medium. The different evaluations of collagen-chitosan scaffold showed that it is relevant to growth of cells (fibroblast and keratinocyte) and has a good flexibility in manipulation of the living skin equivalents. These findings indicate that the integration of collagen-chitosan scaffold with co-cultured keratinocyte and fibroblast in vitro provides a potential source of living skin for grafting in vivo.

Gelatin for purification and proliferation of primary keratinocyte culture for use in chronic wounds and burns.

PubMed

Rahsaz, Marjan; Geramizadeh, Bita; Kaviani, Maryam; Marzban, Saeed

2015-04-01

Human epidermal keratinocytes are currently established as a treatment for burns and wounds and have laboratory applications. Keratinocyte culture contamination by unwanted cells and inhibition of cell proliferation are barriers in primary keratinocyte culture. According to the recent literature, these cells are hard to culture. The present study was conducted to evaluate the efficacy of gelatin-coated surfaces in keratinocyte cultures. After enzymatic isolation of keratinocytes from normal epidermis by trypsin, the cells were cultured on gelatin-coated flasks in serum-free medium. Another group of cells were cultured as a control group without gelatin coating. We showed positive effects of surface coating with gelatin on the primary culture of keratinocytes. Culture of these cells on a gelatincoated surface showed better proliferation with suitable morphology. By using gelatin, adhesion of these cells to the surface was more efficient and without contamination by small round cells. Successful primary culture of keratinocytes on a gelatin-coated surface may provide better yield and optimal number of cells for research and clinical applications.

Effects of medium and trace metals on kinetics of carbon tetrachloride transformation by Pseudomonas sp. strain KC.

PubMed Central

Tatara, G M; Dybas, M J; Criddle, C S

1993-01-01

Under denitrifying conditions, Pseudomonas sp. strain KC transforms carbon tetrachloride (CT) to carbon dioxide via a complex but as yet undetermined mechanism. Transformation rates were first order with respect to CT concentration over the CT concentration range examined (0 to 100 micrograms/liter) and proportional to protein concentration, giving pseudo-second-order kinetics overall. Addition of ferric iron (1 to 20 microM) to an actively transforming culture inhibited CT transformation, and the degree of inhibition increased with increasing iron concentration. By removing iron from the trace metals solution or by removing iron-containing precipitate from the growth medium, higher second-order rate coefficients were obtained. Copper also plays a role in CT transformation. Copper was toxic at neutral pH. By adjusting the medium pH to 8.2, soluble iron and copper levels decreased as a precipitate formed, and CT transformation rates increased. However, cultures grown at high pH without any added trace copper (1 microM) exhibited slower growth rates and greatly reduced rates of CT transformation, indicating that copper is required for CT transformation. The use of pH adjustment to decrease iron solubility, to avoid copper toxicity, and to provide a selective advantage for strain KC was evaluated by using soil slurries and groundwater containing high levels of iron. In samples adjusted to pH 8.2 and inoculated with strain KC, CT disappeared rapidly in the absence or presence of acetate or nitrate supplements. CT did not disappear in pH-adjusted controls that were not inoculated with strain KC. PMID:8357248

The proteinase-activated receptor-2 mediates phagocytosis in a Rho-dependent manner in human keratinocytes.

PubMed

Scott, Glynis; Leopardi, Sonya; Parker, Lorelle; Babiarz, Laura; Seiberg, Miri; Han, Rujiing

2003-09-01

Recent work shows that the G-protein-coupled receptor proteinase activated receptor-2 activates signals that stimulate melanosome uptake in keratinocytes in vivo and in vitro. The Rho family of GTP-binding proteins is involved in cytoskeletal remodeling during phagocytosis. We show that proteinase-activated receptor-2 mediated phagocytosis in human keratinocytes is Rho dependent and that proteinase-activated receptor-2 signals to activate Rho. In contrast, Rho activity did not affect either proteinase-activated receptor-2 activity or mRNA and protein levels. We explored the signaling mechanisms of proteinase-activated receptor-2 mediated Rho activation in human keratinocytes and show that activation of proteinase-activated receptor-2, either through specific proteinase-activated receptor-2 activating peptides or through trypsinization, elevates cAMP in keratinocytes. Proteinase-activated receptor-2 mediated Rho activation was pertussis toxin insensitive and independent of the protein kinase A signaling pathway. These data are the first to show that proteinase-activated receptor-2 mediated phagocytosis is Rho dependent and that proteinase-activated receptor-2 signals to Rho and cAMP in keratinocytes. Because phagocytosis of melanosomes is recognized as an important mechanism for melanosome transfer to keratinocytes, these results suggest that Rho is a critical signaling intermediate in melanosome uptake in keratinocytes.

Immortalized N/TERT keratinocytes as an alternative cell source in 3D human epidermal models.

PubMed

Smits, Jos P H; Niehues, Hanna; Rikken, Gijs; van Vlijmen-Willems, Ivonne M J J; van de Zande, Guillaume W H J F; Zeeuwen, Patrick L J M; Schalkwijk, Joost; van den Bogaard, Ellen H

2017-09-19

The strong societal urge to reduce the use of experimental animals, and the biological differences between rodent and human skin, have led to the development of alternative models for healthy and diseased human skin. However, the limited availability of primary keratinocytes to generate such models hampers large-scale implementation of skin models in biomedical, toxicological, and pharmaceutical research. Immortalized cell lines may overcome these issues, however, few immortalized human keratinocyte cell lines are available and most do not form a fully stratified epithelium. In this study we compared two immortalized keratinocyte cell lines (N/TERT1, N/TERT2G) to human primary keratinocytes based on epidermal differentiation, response to inflammatory mediators, and the development of normal and inflammatory human epidermal equivalents (HEEs). Stratum corneum permeability, epidermal morphology, and expression of epidermal differentiation and host defence genes and proteins in N/TERT-HEE cultures was similar to that of primary human keratinocytes. We successfully generated N/TERT-HEEs with psoriasis or atopic dermatitis features and validated these models for drug-screening purposes. We conclude that the N/TERT keratinocyte cell lines are useful substitutes for primary human keratinocytes thereby providing a biologically relevant, unlimited cell source for in vitro studies on epidermal biology, inflammatory skin disease pathogenesis and therapeutics.

The effects of IL-20 subfamily cytokines on reconstituted human epidermis suggest potential roles in cutaneous innate defense and pathogenic adaptive immunity in psoriasis.

PubMed

Sa, Susan M; Valdez, Patricia A; Wu, Jianfeng; Jung, Kenneth; Zhong, Fiona; Hall, Linda; Kasman, Ian; Winer, Jane; Modrusan, Zora; Danilenko, Dimitry M; Ouyang, Wenjun

2007-02-15

IL-19, IL-20, IL-22, IL-24, and IL-26 are members of the IL-10 family of cytokines that have been shown to be up-regulated in psoriatic skin. Contrary to IL-10, these cytokines signal using receptor complex R1 subunits that are preferentially expressed on cells of epithelial origin; thus, we henceforth refer to them as the IL-20 subfamily cytokines. In this study, we show that primary human keratinocytes (KCs) express receptors for these cytokines and that IL-19, IL-20, IL-22, and IL-24 induce acanthosis in reconstituted human epidermis (RHE) in a dose-dependent manner. These cytokines also induce expression of the psoriasis-associated protein S100A7 and keratin 16 in RHE and cause persistent activation of Stat3 with nuclear localization. IL-22 had the most pronounced effects on KC proliferation and on the differentiation of KCs in RHE, inducing a decrease in the granular cell layer (hypogranulosis). Furthermore, gene expression analysis performed on cultured RHE treated with these cytokines showed that IL-19, IL-20, IL-22, and IL-24 regulate many of these same genes to variable degrees, inducing a gene expression profile consistent with inflammatory responses, wound healing re-epithelialization, and altered differentiation. Many of these genes have also been found to be up-regulated in psoriatic skin, including several chemokines, beta-defensins, S100 family proteins, and kallikreins. These results confirm that IL-20 subfamily cytokines are important regulators of epidermal KC biology with potentially pivotal roles in the immunopathology of psoriasis.

Murine lung eosinophil activation and chemokine production in allergic airway inflammation

PubMed Central

Rose, C Edward; Lannigan, Joanne A; Kim, Paul; Lee, James J; Fu, Shu Man; Sung, Sun-sang J

2010-01-01

Eosinophils play important roles in asthma and lung infections. Murine models are widely used for assessing the functional significance and mechanistic basis for eosinophil involvements in these diseases. However, little is known about tissue eosinophils in homeostasis. In addition, little data on eosinophil chemokine production during allergic airway inflammation are available. In this study, the properties and functions of homeostatic and activated eosinophils were compared. Eosinophils from normal tissues expressed costimulation and adhesion molecules B7-1, B7-2 and ICAM-1 for Ag presentation but little major histocompatibility complex (MHC) class II, and were found to be poor stimulators of T-cell proliferation. However, these eosinophils expressed high levels of chemokine mRNA including C10, macrophage inflammatory protein (MIP)-1α, MIP-1γ, MIP-2, eotaxin and monocyte chemoattractant protein-5 (MCP-5), and produced chemokine proteins. Eosinophil intracellular chemokines decreased rapidly with concomitant surface marker downregulation upon in vitro culturing consistent with piecemeal degranulation. Lung eosinophils from mice with induced allergic airway inflammation exhibited increased chemokines mRNA expression and chemokines protein production and upregulated MHC class II and CD11c expression. They were also found to be the predominant producers of the CCR1 ligands CCL6/C10 and CCL9/MIP-1γ in inflamed lungs. Eosinophil production of C10 and MIP-1γ correlated with the marked influx of CD11bhigh lung dendritic cells during allergic airway inflammation and the high expression of CCR1 on these dendritic cells (DCs). The study provided baseline information on tissue eosinophils, documented the upregulation of activation markers and chemokine production in activated eosinophils, and indicated that eosinophils were a key chemokine-producing cell type in allergic lung inflammation. PMID:20622891

Effect of 1,25-dihydroxyvitamin D3 on human keratinocytes grown under different culture conditions.

PubMed

McLane, J A; Katz, M; Abdelkader, N

1990-04-01

1,25-Dihydroxyvitamin D3 (1,25-(OH)2-D3) is known to decrease the proliferation and increase the differentiation of different cell types including human keratinocytes. The growth and differentiation of keratinocytes in the presence of 1,25-(OH)2-D3 using serum-free media formulations has been described previously. This investigation extends these studies to describe various culture conditions with human foreskin keratinocytes to determine the optimal antiproliferative activity of 1,25-(OH)2-D3. Keratinocytes were plated onto tissue culture dishes using one of three basic serum-free media protocols; a) with no feeder layer in keratinocyte growth medium (KGM); b) onto mitomycin C-treated 3T3 mouse embryo fibroblasts; or c) onto mitomycin C-treated dermal human fibroblasts. The last two protocols utilized Dulbecco's modified Eagle's Medium (DMEM) supplemented with growth factors. Keratinocyte cell growth was greatest in the KGM medium. Although the growth of keratinocytes on either feeder layer was similar, there were differences in the ability of the cells to form envelopes in the presence of 1,25-(OH)2-D3. The addition of hydrocortisone and cholera toxin to the medium also affected the response of the keratinocytes to 1,25-(OH)2-D3. The antiproliferative effect of 1,25-(OH)2-D3 was not altered by varying the extracellular calcium levels from 0.25 to 3 mM. The antiproliferative activity of 1,25-(OH)2-D3 is attenuated in cells at low density. Our results suggest that an optimal condition to investigate the ability of 1,25-(OH)2-D3 to inhibit keratinocyte proliferation is at preconfluent cell density in the presence of KGM supplemented with 1.5 mM calcium without a feeder layer. These conditions are not appropriate for investigating the enhancement of differentiation by 1,25-(OH)2-D3, but can be used to assay other agents that modulate keratinocyte proliferation.

Differential chemokine responses in the murine brain following lyssavirus infection.

PubMed

Hicks, D J; Núñez, A; Banyard, A C; Williams, A; Ortiz-Pelaez, A; Fooks, A R; Johnson, N

2013-11-01

The hallmark of lyssavirus infection is lethal encephalomyelitis. Previous studies have reported distinct lyssavirus isolate-related differences in severity of cellular recruitment into the encephalon in a murine model of infection following peripheral inoculation with rabies virus (RABV) and European bat lyssavirus (EBLV)-1 and -2. In order to understand the role of chemokines in this process, comparative studies of the chemokine pattern, distribution and production in response to infection with these lyssaviruses were undertaken. Expression of CCL2, CCL5 and CXCL10 was observed throughout the murine brain with a distinct caudal bias in distribution, similar to both inflammatory changes and virus antigen distribution. CCL2 immunolabelling was localized to neuronal and astroglial populations. CCL5 immunolabelling was only detected in the astroglia, while CXCL10 labelling, although present in the astroglia, was more prominent in neurons. Isolate-dependent differences in the amount of chemokine immunolabelling in specific brain regions and chemokine production by neurons in vitro were observed, with a greater expression of CCL5 in vivo and CXCL10 production in vitro after EBLV infection. Additionally, strong positive associations between chemokine immunolabelling and perivascular cuffing and, to a lesser extent, virus antigen score were also observed. These differences in chemokine expression may explain the variation in severity of encephalitic changes observed in animals infected with different lyssavirus isolates. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Air Force KC-X Tanker Aircraft Program: Background and Issues for Congress

DTIC Science & Technology

2009-10-05

General ..................................................................................................................... 12 Best Value vs . Lowest...Druyan was a single “bad apple ” and that her actions did not negate the merits of leasing Boeing 767s for use as tankers. In February 2005, however...Force KC-X Tanker Aircraft Program: Background and Issues for Congress Congressional Research Service 17 Best Value vs . Lowest Cost The question of

Chemokines in the cancer microenvironment and their relevance in cancer immunotherapy

PubMed Central

Nagarsheth, Nisha; Wicha, Max S.; Zou, Weiping

2017-01-01

The tumour microenvironment is the primary location in which tumour cells and the host immune system interact. Different immune cell subsets are recruited into the tumour microenvironment via interactions between chemokines and chemokine receptors, and these populations have distinct effects on tumour progression and therapeutic outcomes. In this Review, we focus on the main chemokines that are found in the human tumour microenvironment; we elaborate on their patterns of expression, their regulation and their roles in immune cell recruitment and in cancer and stromal cell biology, and we consider how they affect cancer immunity and tumorigenesis. We also discuss the potential of targeting chemokine networks, in combination with other immunotherapies, for the treatment of cancer. PMID:28555670

Novel Function for Vascular Endothelial Growth Factor Receptor-1 on Epidermal Keratinocytes

PubMed Central

Wilgus, Traci A.; Matthies, Annette M.; Radek, Katherine A.; Dovi, Julia V.; Burns, Aime L.; Shankar, Ravi; DiPietro, Luisa A.

2005-01-01

Vascular endothelial growth factor (VEGF-A), a potent stimulus for angiogenesis, is up-regulated in the skin after wounding. Although studies have shown that VEGF is important for wound repair, it is unclear whether this is based solely on its ability to promote angiogenesis or if VEGF can also promote healing by acting directly on non-endothelial cell types. By immunohistochemistry and reverse transcriptase-polymerase chain reaction, expression of VEGF receptor-1 (VEGFR-1), but not VEGFR-2, was detected in murine keratinocytes during wound repair and in normal human epidermal keratinocytes (NHEKs). The presence of VEGF receptors on NHEKs was verified by binding studies with 125I-VEGF. In vitro, VEGF stimulated the proliferation of NHEKs, an effect that could be blocked by treatment with neutralizing VEGFR-1 antibodies. A role for VEGFR-1 in keratinocytes was also shown in vivo because treatment of excisional wounds with neutralizing VEGFR-1 antibodies delayed re-epithelialization. Treatment with anti-VEGFR-1 antibodies also reduced the number of proliferating keratinocytes at the leading edge of the wound, suggesting that VEGF sends a proliferative signal to these cells. Together, these data describe a novel role for VEGFR-1 in keratinocytes and suggest that VEGF may play several roles in cutaneous wound repair. PMID:16251410

Transduction of beta3 integrin subunit cDNA confers on human keratinocytes the ability to adhere to gelatin.

PubMed

Kubo, Miyoko; Clark, Richard A F; Katz, Anne B; Taichman, Lorne B; Jin, Zaishun; Zhao, Ying; Moriguchi, Takahiko

2007-04-01

alphavbeta3 is a multiligand integrin receptor that interacts with fibrinogen (FG), fibrin (FB), fibronectin (FN), vitronectin (VN), and denatured collagen. We previously reported that cultured normal human keratinocytes, like in vivo keratinocytes, do not express alphavbeta3 on the cell surface, and do not adhere to and migrate on FG and FB. Furthermore, we reported that human keratinocytes transduced with beta3 integrin subunit cDNA by a retrovirus-mediated transduction method express alphavbeta3 on the cell surface and adhere to FG, FB, FN, and VN significantly compared with beta-galactosidase (beta-gal) cDNA-transduced keratinocytes (control). In this study, we determined whether these beta3 integrin subunit cDNA-transduced keratinocytes or normal human keratinocytes adhere to denatured collagen (gelatin) using a 1 h cell adhesion assay. beta3 cDNA-transduced keratinocytes adhered to gelatin, whereas no significant adhesion was observed with the control cells (beta-gal cDNA-transduced keratinocytes and normal human keratinocytes). The adhesion to gelatin was inhibited by LM609, a monoclonal antibody to alphavbeta3, and RGD peptides but not by normal mouse IgG1 nor RGE peptides. Thus, transduction of beta3 integrin subunit cDNA confers on human keratinocytes the ability to adhere to denatured collagen (gelatin) as well as to FG, FB, VN, and FN. Otherwise, normal human keratinocytes do not adhere to gelatin. These data support the idea that beta3 cDNA-transduced human keratinocytes can be a good material for cultured epithelium to achieve better take rate with acute or chronic wounds, in which FG, FB, and denatured collagen are abundantly present.

Enzyme-Treated Asparagus Extract (ETAS) Facilitates the Turnover of UV-B-Irradiated Keratinocytes.

PubMed

Koda, Tomoko; Shirato, Ken; Takanari, Jun; Imai, Hideki

2018-01-01

Enzyme-treated asparagus extract (ETAS) is prepared from the lower, residual parts of asparagus, and some functionalities, such as anti-oxidative and neuroprotective activities, have been suggested. The purpose of the present study was to investigate the effects of ETAS on photoaging in the epidermal layer of the skin using cultured keratinocytes. Normal human epidermal keratinocytes were irradiated or left unirradiated with UV-B (10 mJ/cm 2 ) and incubated with ETAS (0.5 or 2 mg/mL) or vehicle. After 3 or 13 h, molecular examinations were performed, and after 24 or 48 h, cell viabilities were determined by a CCK-8 assay. ETAS addition may induce keratinocyte migration and proliferation as well as apoptosis under molecular examination. These results suggest that ETAS might accelerate turnover of keratinocytes.

Evidence for chemokine synergy during neutrophil migration in ARDS.

PubMed

Williams, Andrew E; José, Ricardo J; Mercer, Paul F; Brealey, David; Parekh, Dhruv; Thickett, David R; O'Kane, Cecelia; McAuley, Danny F; Chambers, Rachel C

2017-01-01

Acute respiratory distress syndrome (ARDS) is a life-threatening condition characterised by pulmonary oedema, respiratory failure and severe inflammation. ARDS is further characterised by the recruitment of neutrophils into the lung interstitium and alveolar space. The factors that regulate neutrophil infiltration into the inflamed lung and our understanding of the pathomechanisms in ARDS remain incomplete. This study aimed at determining the role of the chemokine (C-C motif) ligand (CCL)2 and CCL7 in ARDS. CCL2 and CCL7 protein levels were measured in bronchoalveolar lavage (BAL) fluid obtained from lipopolysaccharide(LPS)-challenged human volunteers and two separate cohorts of patients with ARDS. Neutrophil chemotaxis to ARDS BAL fluid was evaluated and the contribution of each was assessed and compared with chemokine (C-X-C motif) ligand 8 (CXCL8). Chemokine receptor expression on neutrophils from blood or BAL fluid of patients with ARDS was analysed by flow cytometry. CCL2 and CCL7 were significantly elevated in BAL fluid recovered from LPS-challenged volunteers and patients with ARDS. BAL fluid from patients with ARDS was highly chemotactic for human neutrophils and neutralising either CCL2 or CCL7 attenuated the neutrophil chemotactic response. Moreover, CCL2 and CCL7 synergised with CXCL8 to promote neutrophil migration. Furthermore, neutrophils isolated from the blood or BAL fluid differentially regulated the cell surface expression of chemokine (C-X-C motif) receptor 1 and C-C chemokine receptor type 2 during ARDS. This study highlights important inflammatory chemokines involved in regulating neutrophil migration, which may have potential value as therapeutic targets for the treatment of ARDS. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Role of CXC group chemokines in lung cancer development and progression.

PubMed

Spaks, Artjoms

2017-04-01

Clinical and translational research on lung cancer patients undergoing surgical treatment can provide valuable scientific data and unique opportunity to study tumor microenvironment. CXC chemokines, which are members of a big family of cytokines, are undoubtedly involved in tumor growth regulation and metastasizing pathways. For better understanding of CXC chemokine involvement in the process of carcinogenesis we have studied the cohort of early stage non-small cell lung cancer patients undergoing surgery with curative intent. Our aim was to assess CXC chemokine ligand (CXCL) levels in patient blood samples representing systemic circulation and tumor microenvironment; assess CXC chemokine receptor (CXCR) expression in tumor tissue; and measure tumor infiltrating immune cell subpopulations. A total of 54 patients with NSCLC had radical lung resection were enrolled in a single center prospective study and were followed-up annually for up to six years. During surgical procedure peripheral and tumor draining blood samples were taken. CXCL1, CXCL4, CXCL5, CXCL6, CXCL7, CXCL8, CXCL9, CXCL10, CXCL11 and CXCL12 levels were determined by ELISA, and chemokine concentration gradient was calculated. Tumor infiltrating immune cells (T helper cells, T cytotoxic cells, macrophages, B cells, plasma cells) and expression of CXCR1, CXCR2, CXCR3 and CXCR4 in tumor tissue were assessed by immunohistochemistry. Statistically significant decrease in chemokine concentration was found for CXCL4 (P=0.002) and CXCL5 (P=0.011), and statistically significant concentration increase was found for CXCL7 (P=0.001) in total cohort. We have found statistically significant CXC chemokine concentration change for majority of chemokines-CXCL1 (P=0.002), CXCL4 (P=0.001), CXCL5 (P=0.013), CXCL7 (P=0.036), CXCL8 (P=0.026), CXCL9 (P=0.034) and CXCL10 (P=0.032) in a group of patients who had good clinical result after surgery with no evidence of relapse, on the other hand patients with cancer recurrence

Integrin-linked kinase and ELMO2 modulate recycling endosomes in keratinocytes.

PubMed

Ho, Ernest; Ivanova, Iordanka A; Dagnino, Lina

2016-12-01

The formation of tight cell-cell junctions is essential in the epidermis for its barrier properties. In this tissue, keratinocytes follow a differentiation program tightly associated with their movement from the innermost basal to the outer suprabasal layers, and with changes in their cell-cell adhesion profile. Intercellular adhesion in keratinocytes is mediated through cell-cell contacts, including E-cadherin-based adherens junctions. Although the mechanisms that mediate E-cadherin delivery to the plasma membrane have been widely studied in simple epithelia, this process is less well understood in the stratified epidermis. In this study, we have investigated the role of Engulfment and Cell Motility 2 (ELMO2) and integrin-linked kinase (ILK) in the positioning of E-cadherin-containing recycling endosomes during establishment of cell-cell contacts in differentiating keratinocytes. We now show that induction of keratinocyte differentiation by Ca 2+ is accompanied by localization of ELMO2 and ILK to Rab4- and Rab11a-containing recycling endosomes. The positioning of long-loop Rab11a-positive endosomes at areas adjacent to cell-cell contacts is disrupted in ELMO2- or ILK-deficient keratinocytes, and is associated with impaired localization of E-cadherin to cell borders. Our studies show a previously unrecognized role for ELMO2 and ILK in modulation of endosomal positioning, which may play key roles in epidermal sheet maintenance and permeability barrier function. Copyright © 2016 Elsevier B.V. All rights reserved.

(+)-Nootkatone inhibits tumor necrosis factor α/interferon γ-induced production of chemokines in HaCaT cells

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

Choi, Hyeon-Jae; Lee, Jin-Hwee; Jung, Yi-Sook, E-mail: yisjung@ajou.ac.kr

Highlights: • (+)-Nootkatone inhibits TNF-α/IFN-γ-induced TARC and MDC expression in HaCaT cells. • PKCζ, p38 MAPK, or NF-κB mediate TNF-α/IFN-γ-induced TARC and MDC expression. • (+)-Nootkatone inhibits TNF-α/IFN-γ-induced activation of PKCζ, p38 MAPK, or NF-κB. • (+)-Nootkatone suppresses chemokine expression by inhibiting of PKCζ and p38 pathways. - Abstract: Chemokines are important mediators of cell migration, and thymus and activation-regulated chemokine (TARC/CCL17) and macrophage-derived chemokine (MDC/CCL22) are well-known typical inflammatory chemokines involved in atopic dermatitis (AD). (+)-Nootkatone is the major component of Cyperus rotundus. (+)-Nootkatone has antiallergic, anti-inflammatory, and antiplatelet activities. The purpose of this study was to investigate themore » effect of (+)-nootkatone on tumor necrosis factor α (TNF-α)/interferon γ (IFN-γ)-induced expression of Th2 chemokines in HaCaT cells. We found that (+)-nootkatone inhibited the TNF-α/IFN-γ-induced expression of TARC/CCL17 and MDC/CCL22 mRNA in HaCaT cells. It also significantly inhibited TNF-α/IFN-γ-induced activation of nuclear factor kappa B (NF-κB), p38 mitogen-activated protein kinase (MAPK), and protein kinase Cζ (PKCζ). Furthermore, we showed that PKCζ and p38 MAPK contributed to the inhibition of TNF-α/IFN-γ-induced TARC/CCL17 and MDC/CCL22 expression by blocking IκBα degradation in HaCaT cells. Taken together, these results suggest that (+)-nootkatone may suppress TNF-α/IFN-γ-induced TARC/CCL17 and MDC/CCL22 expression in HaCaT cells by inhibiting of PKCζ and p38 MAPK signaling pathways that lead to activation of NF-κB. We propose that (+)-nootkatone may be a useful therapeutic candidate for inflammatory skin diseases such as AD.« less

The CC chemokine receptor 5 regulates olfactory and social recognition in mice.

PubMed

Kalkonde, Y V; Shelton, R; Villarreal, M; Sigala, J; Mishra, P K; Ahuja, S S; Barea-Rodriguez, E; Moretti, P; Ahuja, S K

2011-12-01

Chemokines are chemotactic cytokines that regulate cell migration and are thought to play an important role in a broad range of inflammatory diseases. The availability of chemokine receptor blockers makes them an important therapeutic target. In vitro, chemokines are shown to modulate neurotransmission. However, it is not very clear if chemokines play a role in behavior and cognition. Here we evaluated the role of CC chemokine receptor 5 (CCR5) in various behavioral tasks in mice using Wt (Ccr5⁺/⁺) and Ccr5-null (Ccr5⁻/⁻)mice. Ccr5⁻/⁻ mice showed enhanced social recognition. Administration of CC chemokine ligand 3 (CCL3), one of the CCR5-ligands, impaired social recognition. Since the social recognition task is dependent on the sense of olfaction, we tested olfactory recognition for social and non-social scents in these mice. Ccr5⁻/⁻ mice had enhanced olfactory recognition for both these scents indicating that enhanced performance in social recognition task could be due to enhanced olfactory recognition in these mice. Spatial memory and aversive memory were comparable in Wt and Ccr5⁻/⁻ mice. Collectively, these results suggest that chemokines/chemokine receptors might play an important role in olfactory recognition tasks in mice and to our knowledge represents the first direct demonstration of an in vivo role of CCR5 in modulating social behavior in mice. These studies are important as CCR5 blockers are undergoing clinical trials and can potentially modulate behavior. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

Pimecrolimus enhances TLR2/6-induced expression of antimicrobial peptides in keratinocytes.

PubMed

Büchau, Amanda S; Schauber, Jürgen; Hultsch, Thomas; Stuetz, Anton; Gallo, Richard L

2008-11-01

Calcineurin inhibitors are potent inhibitors of T-cell-receptor mediated activation of the adaptive immune system. The effects of this class of drug on the innate immune response system are not known. Keratinocytes are essential to innate immunity in skin and rely on toll-like receptors (TLRs) and antimicrobial peptides to appropriately recognize and respond to injury or microbes. In this study we examined the response of cultured human keratinocytes to pimecrolimus. We observed that pimecrolimus enhances distinct expression of cathelicidin, CD14, and human beta-defensin-2 and beta-defensin-3 in response to TLR2/6 ligands. Some of these responses were further enhanced by 1,25 vitamin D3. Pimecrolimus also increased the functional capacity of keratinocytes to inhibit growth of Staphylococcus aureus and decreased TLR2/6-induced expression of IL-10 and IL-1beta. Furthermore, pimecrolimus inhibited nuclear translocation of NFAT and NF-kappaB in keratinocytes. These observations uncover a previously unreported function for pimecrolimus in cutaneous innate host defense.

Tumor-derived CXCL8 signaling augments stroma-derived CCL2-promoted proliferation and CXCL12-mediated invasion of PTEN-deficient prostate cancer cells

PubMed Central

Maxwell, Pamela J.; Neisen, Jessica; Messenger, Johanna; Waugh, David J.J.

2014-01-01

Impaired PTEN function is a genetic hallmark of aggressive prostate cancers (CaP) and is associated with increased CXCL8 expression and signaling. The current aim was to further characterize biological responses and mechanisms underpinning CXCL8-promoted progression of PTEN-depleted prostate cancer, focusing on characterizing the potential interplay between CXCL8 and other disease-promoting chemokines resident within the prostate tumor microenvironment. Autocrine CXCL8-stimulation (i) increased expression of CXCR1 and CXCR2 in PTEN-deficient CaP cells suggesting a self-potentiating signaling axis and (ii) induced expression of CXCR4 and CCR2 in PTEN-wild-type and PTEN-depleted CaP cells. In contrast, paracrine CXCL8 signaling induced expression and secretion of the chemokines CCL2 and CXCL12 from prostate stromal WPMY-1 fibroblasts and monocytic macrophage-like THP-1 cells. In vitro studies demonstrated functional co-operation of tumor-derived CXCL8 with stromal-derived chemokines. CXCL12-induced migration of PC3 cells and CCL2-induced proliferation of prostate cancer cells were dependent upon intrinsic CXCL8 signaling within the prostate cancer cells. For example, in co-culture experiments, CXCL12/CXCR4 signaling but not CCL2/CCR2 signaling supported fibroblast-mediated migration of PC3 cells while CXCL12/CXCR4 and CCL2/CCR2 signaling underpinned monocyte-enhanced migration of PC3 cells. Combined inhibition of both CXCL8 and CXCL12 signaling was more effective in inhibiting fibroblast-promoted cell motility while repression of CXCL8 attenuated CCL2-promoted proliferation of prostate cancer cells. We conclude that tumor-derived CXCL8 signaling from PTEN-deficient tumor cells increases the sensitivity and responsiveness of CaP cells to stromal chemokines by concurrently upregulating receptor expression in cancer cells and inducing stromal chemokine synthesis. Combined chemokine targeting may be required to inhibit their multi-faceted actions in promoting the

Chemokine RANTES in atopic dermatitis.

PubMed

Glück, J; Rogala, B

1999-01-01

Chemokines play a key role in inflammatory diseases. The aim of this study was to estimate chemokine RANTES in the sera of patients with atopic dermatitis (AD) and to analyze the correlation between RANTES serum level and the immunological and clinical parameters of the disease. Serum levels of RANTES (ELISA; R&D Systems), total IgE and specific IgE (FEIA; Pharmacia CAP System) were estimated in 24 patients with AD, 28 patients with pollinosis (PL) and 22 healthy nonatopic subjects (HC). The division of the AD group into a pure AD (pAD) subgroup, without a coexisting respiratory allergy, and a subgroup of patients with AD and a respiratory allergy (AD+AO) was done according to Wütrich. Levels of RANTES were higher in the AD group than in the HC group and the PL group. RANTES levels did not differ among subgroups with various clinical scores and between the pAD and AD+AO subgroups. There were no correlations between levels of RANTES and total IgE. Significant positive correlations between serum levels of RANTES and Dermatophagoides farinae and cat dander-specific IgE were found in the AD group. We conclude that the serum level of chemokine RANTES differs patients with AD from patients with PL. The increase of RANTES concentration in the serum of patients with AD depends neither on a clinical picture nor an IgE system.

AKT delays the early-activated apoptotic pathway in UVB-irradiated keratinocytes via BAD translocation.

PubMed

Claerhout, Sofie; Decraene, David; Van Laethem, An; Van Kelst, Sofie; Agostinis, Patrizia; Garmyn, Marjan

2007-02-01

Upon irradiation with a high dose of UVB, keratinocytes undergo apoptosis as a protective mechanism. In previous work, we demonstrated the existence of an early-activated UVB-induced apoptotic pathway in growth factor-depleted human keratinocytes, which can be substantially delayed by the exclusive supplementation of IGF-1. We now show that in human keratinocytes, IGF-1 inhibits the onset of UVB-triggered apoptosis through a transcriptional independent, AKT-mediated mechanism, involving BAD serine 136 phosphorylation. Our results show that the early UVB-induced apoptosis in growth factor-depleted human keratinocytes is exclusively triggered through the mitochondrial pathway. It is accompanied by BAX translocation, cytochrome c release, and procaspase-9 cleavage, but not by procaspase-8 or BID cleavage. In human keratinocytes, IGF-1 supplementation inhibits these events in a transcription-independent manner. Both IGF-1 supplementation and the transduction of a membrane-targeted form of AKT result in a shift of the BH3-only protein BAD from the mitochondria to the cytoplasm, paralleled by an increase of AKT-specific Ser136 phospho-BAD bound to 14-3-3zeta protein. These data indicate that AKT-induced BAD phosphorylation and its subsequent cytoplasmic sequestration by 14-3-3zeta is a major mechanism responsible for the postponement of UVB-induced apoptosis in human keratinocytes.

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

PubMed

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

2003-03-28

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

Enhanced secretion of TIMP-1 by human hypertrophic scar keratinocytes could contribute to fibrosis.

PubMed

Simon, Franck; Bergeron, Daniele; Larochelle, Sébastien; Lopez-Vallé, Carlos A; Genest, Hervé; Armour, Alexis; Moulin, Véronique J

2012-05-01

Hypertrophic scars are a pathological process characterized by an excessive deposition of extracellular matrix components. Using a tissue-engineered reconstructed human skin (RHS) method, we previously reported that pathological keratinocytes induce formation of a fibrotic dermal matrix. We further investigated keratinocyte action using conditioned media. Results showed that conditioned media induce a similar action on dermal thickness similar to when an epidermis is present. Using a two-dimensional electrophoresis technique, we then compared conditioned media from normal or hypertrophic scar keratinocytes and determined that TIMP-1 was increased in conditioned media from hypertrophic scar keratinocytes. This differential profile was confirmed using ELISA, assaying TIMP-1 presence on media from monolayer cultured keratinocytes and from RHS. The dermal matrix of these RHS was recreated using mesenchymal cells from three different origins (skin, wound and hypertrophic scar). The effect of increased TIMP-1 levels on dermal fibrosis was also validated independently from the mesenchymal cell origin. Immunodetection of TIMP-1 showed that this protein was increased in the epidermis of hypertrophic scar biopsies. The findings of this study represent an important advance in understanding the role of keratinocytes as a direct potent modulator for matrix degradation and scar tissue remodeling, possibly through inactivation of MMPs. Copyright © 2011 Elsevier Ltd and ISBI. All rights reserved.

Atypical Diabetic Foot Ulcer Keratinocyte Protein Signaling Correlates with Impaired Wound Healing.

PubMed

Hoke, Glenn D; Ramos, Corrine; Hoke, Nicholas N; Crossland, Mary C; Shawler, Lisa G; Boykin, Joseph V

2016-01-01

Diabetes mellitus is associated with chronic diabetic foot ulcers (DFUs) and wound infections often resulting in lower extremity amputations. The protein signaling architecture of the mechanisms responsible for impaired DFU healing has not been characterized. In this preliminary clinical study, the intracellular levels of proteins involved in signal transduction networks relevant to wound healing were non-biasedly measured using reverse-phase protein arrays (RPPA) in keratinocytes isolated from DFU wound biopsies. RPPA allows for the simultaneous documentation and assessment of the signaling pathways active in each DFU. Thus, RPPA provides for the accurate mapping of wound healing pathways associated with apoptosis, proliferation, senescence, survival, and angiogenesis. From the study data, we have identified potential diagnostic, or predictive, biomarkers for DFU wound healing derived from the ratios of quantified signaling protein expressions within interconnected pathways. These biomarkers may allow physicians to personalize therapeutic strategies for DFU management on an individual basis based upon the signaling architecture present in each wound. Additionally, we have identified altered, interconnected signaling pathways within DFU keratinocytes that may help guide the development of therapeutics to modulate these dysregulated pathways, many of which parallel the therapeutic targets which are the hallmarks of molecular therapies for treating cancer.

Atypical Diabetic Foot Ulcer Keratinocyte Protein Signaling Correlates with Impaired Wound Healing

PubMed Central

Hoke, Glenn D.; Ramos, Corrine; Hoke, Nicholas N.; Crossland, Mary C.; Shawler, Lisa G.

2016-01-01

Diabetes mellitus is associated with chronic diabetic foot ulcers (DFUs) and wound infections often resulting in lower extremity amputations. The protein signaling architecture of the mechanisms responsible for impaired DFU healing has not been characterized. In this preliminary clinical study, the intracellular levels of proteins involved in signal transduction networks relevant to wound healing were non-biasedly measured using reverse-phase protein arrays (RPPA) in keratinocytes isolated from DFU wound biopsies. RPPA allows for the simultaneous documentation and assessment of the signaling pathways active in each DFU. Thus, RPPA provides for the accurate mapping of wound healing pathways associated with apoptosis, proliferation, senescence, survival, and angiogenesis. From the study data, we have identified potential diagnostic, or predictive, biomarkers for DFU wound healing derived from the ratios of quantified signaling protein expressions within interconnected pathways. These biomarkers may allow physicians to personalize therapeutic strategies for DFU management on an individual basis based upon the signaling architecture present in each wound. Additionally, we have identified altered, interconnected signaling pathways within DFU keratinocytes that may help guide the development of therapeutics to modulate these dysregulated pathways, many of which parallel the therapeutic targets which are the hallmarks of molecular therapies for treating cancer. PMID:27840833

Transient Receptor Potential Vanilloid 4 Ion Channel Functions as a Pruriceptor in Epidermal Keratinocytes to Evoke Histaminergic Itch*

PubMed Central

Chen, Yong; Fang, Quan; Wang, Zilong; Zhang, Jennifer Y.; MacLeod, Amanda S.; Hall, Russell P.; Liedtke, Wolfgang B.

2016-01-01

TRPV4 ion channels function in epidermal keratinocytes and in innervating sensory neurons; however, the contribution of the channel in either cell to neurosensory function remains to be elucidated. We recently reported TRPV4 as a critical component of the keratinocyte machinery that responds to ultraviolet B (UVB) and functions critically to convert the keratinocyte into a pain-generator cell after excess UVB exposure. One key mechanism in keratinocytes was increased expression and secretion of endothelin-1, which is also a known pruritogen. Here we address the question of whether TRPV4 in skin keratinocytes functions in itch, as a particular form of “forefront” signaling in non-neural cells. Our results support this novel concept based on attenuated scratching behavior in response to histaminergic (histamine, compound 48/80, endothelin-1), not non-histaminergic (chloroquine) pruritogens in Trpv4 keratinocyte-specific and inducible knock-out mice. We demonstrate that keratinocytes rely on TRPV4 for calcium influx in response to histaminergic pruritogens. TRPV4 activation in keratinocytes evokes phosphorylation of mitogen-activated protein kinase, ERK, for histaminergic pruritogens. This finding is relevant because we observed robust anti-pruritic effects with topical applications of selective inhibitors for TRPV4 and also for MEK, the kinase upstream of ERK, suggesting that calcium influx via TRPV4 in keratinocytes leads to ERK-phosphorylation, which in turn rapidly converts the keratinocyte into an organismal itch-generator cell. In support of this concept we found that scratching behavior, evoked by direct intradermal activation of TRPV4, was critically dependent on TRPV4 expression in keratinocytes. Thus, TRPV4 functions as a pruriceptor-TRP in skin keratinocytes in histaminergic itch, a novel basic concept with translational-medical relevance. PMID:26961876

Structural Basis of Chemokine Sequestration by CrmD, a Poxvirus-Encoded Tumor Necrosis Factor Receptor

PubMed Central

Wang, Dongli; Chen, Dongwei; He, Guangjun; Huang, Li; Wang, Hanzhong; Wang, Xinquan

2011-01-01

Pathogens have evolved sophisticated mechanisms to evade detection and destruction by the host immune system. Large DNA viruses encode homologues of chemokines and their receptors, as well as chemokine-binding proteins (CKBPs) to modulate the chemokine network in host response. The SECRET domain (smallpox virus-encoded chemokine receptor) represents a new family of viral CKBPs that binds a subset of chemokines from different classes to inhibit their activities, either independently or fused with viral tumor necrosis factor receptors (vTNFRs). Here we present the crystal structures of the SECRET domain of vTNFR CrmD encoded by ectromelia virus and its complex with chemokine CX3CL1. The SECRET domain adopts a β-sandwich fold and utilizes its β-sheet I surface to interact with CX3CL1, representing a new chemokine-binding manner of viral CKBPs. Structure-based mutagenesis and biochemical analysis identified important basic residues in the 40s loop of CX3CL1 for the interaction. Mutation of corresponding acidic residues in the SECRET domain also affected the binding for other chemokines, indicating that the SECRET domain binds different chemokines in a similar manner. We further showed that heparin inhibited the binding of CX3CL1 by the SECRET domain and the SECRET domain inhibited RAW264.7 cell migration induced by CX3CL1. These results together shed light on the structural basis for the SECRET domain to inhibit chemokine activities by interfering with both chemokine-GAG and chemokine-receptor interactions. PMID:21829356

The Atypical Chemokine Receptor ACKR2 is Protective Against Sepsis.

PubMed

Castanheira, Fernanda V E Silva; Borges, Vanessa; Sônego, Fabiane; Kanashiro, Alexandre; Donate, Paula B; Melo, Paulo H; Pallas, Kenneth; Russo, Remo C; Amaral, Flávio A; Teixeira, Mauro M; Ramalho, Fernando S; Cunha, Thiago M; Liew, Foo Y; Alves-Filho, José C; Graham, Gerard J; Cunha, Fernando Q

2018-06-01

Sepsis is a systemic inflammatory response as a result of uncontrolled infections. Neutrophils are the first cells to reach the primary sites of infection, and chemokines play a key role in recruiting neutrophils. However, in sepsis chemokines could also contribute to neutrophil infiltration to vital organs leading to multiple organ failure. ACKR2 is an atypical chemokine receptor, which can remove and degrade inflammatory CC chemokines. The role of ACK2 in sepsis is unknown. Using a model of cecal ligation and puncture (CLP), we demonstrate here that ACKR2 deficient () mice exhibited a significant reduction in the survival rate compared with similarly treated wild-type (WT) mice. However, neutrophil migration to the peritoneal cavity and bacterial load were similar between WT and ACKR2 mice during CLP. In contrast, ACKR2 mice showed increased neutrophil infiltration and elevated CC chemokine levels in the lung, kidney, and heart compared with the WT mice. In addition, ACKR2 mice also showed more severe lesions in the lung and kidney than those in the WT mice. Consistent with these results, WT mice under nonsevere sepsis (90% survival) had higher expression of ACKR2 in these organs than mice under severe sepsis (no survival). Finally, the lungs from septic patients showed increased number of ACKR2 cells compared with those of nonseptic patients. Our data indicate that ACKR2 may have a protective role during sepsis, and the absence of ACKR2 leads to exacerbated chemokine accumulation, neutrophil infiltration, and damage to vital organs.

In vivo production of novel vitamin D2 hydroxy-derivatives by human placentas, epidermal keratinocytes, Caco-2 colon cells and the adrenal gland

PubMed Central

Slominski, Andrzej T.; Kim, Tae-Kang; Shehabi, Haleem Z.; Tang, Edith; Benson, Heather A. E.; Semak, Igor; Lin, Zongtao; Yates, Charles R.; Wang, Jin; Li, Wei; Tuckey, Robert C.

2014-01-01

We investigated the metabolism of vitamin D2 to hydroxyvitamin D2 metabolites ((OH)D2) by human placentas ex-utero, adrenal glands ex-vivo and cultured human epidermal keratinocytes and colonic Caco-2 cells, and identified 20(OH)D2, 17,20(OH)2D2, 1,20(OH)2D2, 25(OH)D2 and 1,25(OH)2D2 as products. Inhibition of product formation by 22R-hydroxycholesterol indicated involvement of CYP11A1 in 20- and 17-hydroxylation of vitamin D2, while use of ketoconazole indicated involvement of CYP27B1 in 1α-hydroxylation of products. Studies with purified human CYP11A1 confirmed the ability of this enzyme to convert vitamin D2 to 20(OH)D2 and 17,20(OH)2D2. In placentas and Caco-2 cells, production of 20(OH)D2 was higher than 25(OH)D2 while in human keratinocytes the production of 20(OH)D2 and 25(OH)D2 were comparable. HaCaT keratinocytes showed high accumulation of 1,20(OH)2D2 relative to 20(OH)D2 indicating substantial CYP27B1 activity. This is the first in vivo evidence for a novel pathway of vitamin D2 metabolism initiated by CYP11A1 and modified by CYP27B1, with the product profile showing tissue- and cell-type specificity. PMID:24382416

Exogenous hydrogen sulfide promotes cell proliferation and differentiation by modulating autophagy in human keratinocytes

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

Xie, Xin; Dai, Hui; Zhuang, Binyu

The effects and the underlying mechanisms of hydrogen sulfide (H{sub 2}S) on keratinocyte proliferation and differentiation are still less known. In the current study, we investigated the effects and the underlying mechanisms of exogenous H{sub 2}S on keratinocyte proliferation and differentiation. Human keratinocytes (HaCaT cells) were treated with various concentrations (0.05, 0.25, 0.5 and 1 mM) of sodium hydrosulfide (NaHS, a donor of H{sub 2}S) for 24 h. A CCK-8 assay was used to assess cell viability. Western blot analysis was performed to determine the expression levels of proteins associated with differentiation and autophagy. Transmission electron microscopy was performed to observe autophagicmore » vacuoles, and flow cytometry was applied to evaluate apoptosis. NaHS promoted the viability, induced the differentiation, and enhanced autophagic activity in a dose-dependent manner in HaCaT cells but had no effect on cell apoptosis. Blockage of autophagy by ATG5 siRNA inhibited NaHS-induced cell proliferation and differentiation. The current study demonstrated that autophagy in response to exogenous H{sub 2}S treatment promoted keratinocyte proliferation and differentiation. Our results provide additional insights into the potential role of autophagy in keratinocyte proliferation and differentiation. - Highlights: • Exogenous H{sub 2}S promotes keratinocyte proliferation and differentiation. • The effects of H{sub 2}S on proliferation and differentiation is modulated by autophagy. • Exogenous H{sub 2}S has no effect on keratinocyte apoptosis.« less

H{sup +}/peptide transporter (PEPT2) is expressed in human epidermal keratinocytes and is involved in skin oligopeptide transport

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

Kudo, Michiko; Katayoshi, Takeshi; Kobayashi-Nakamura, Kumiko

Peptide transporter 2 (PEPT2) is a member of the proton-coupled oligopeptide transporter family, which mediates the cellular uptake of oligopeptides and peptide-like drugs. Although PEPT2 is expressed in many tissues, its expression in epidermal keratinocytes remains unclear. We investigated PEPT2 expression profile and functional activity in keratinocytes. We confirmed PEPT2 mRNA expression in three keratinocyte lines (normal human epidermal keratinocytes (NHEKs), immortalized keratinocytes, and malignant keratinocytes) by reverse transcription-polymerase chain reaction (RT-PCR) and quantitative real-time RT-PCR. In contrast to PEPT1, PEPT2 expression in the three keratinocytes was similar or higher than that in HepG2 cells, used as PEPT2-positive cells. Immunolocalizationmore » analysis using human skin showed epidermal PEPT2 localization. We studied keratinocyte transport function by measuring the oligopeptide content using liquid chromatography/tandem mass spectrometry. Glycylsarcosine uptake in NHEKs was pH-dependent, suggesting that keratinocytes could absorb small peptides in the presence of an inward H{sup +} gradient. We also performed a skin-permeability test of several oligopeptides using skin substitute, suggesting that di- and tripeptides pass actively through the epidermis. In conclusion, PEPT2 is expressed in keratinocytes and involved in skin oligopeptide uptake. -- Highlights: •PEPT2 is expressed in keratinocytes, which are more common than other skin cells. •Immunolocalization analysis using human skin revealed epidermal PEPT2 localization. •Keratinocytes could absorb small peptides in the presence of an inward H{sup +} gradient. •Di- and tripeptide pass actively through the epidermis.« less

Calcium ion propagation in cultured keratinocytes and other cells in skin in response to hydraulic pressure stimulation.

PubMed

Goto, Makiko; Ikeyama, Kazuyuki; Tsutsumi, Moe; Denda, Sumiko; Denda, Mitsuhiro

2010-07-01

We have previously suggested that a variety of environmental factors might be first sensed by epidermal keratinocytes, which represent the frontier of the body. To further examine this idea, in the present study, we examined the intracellular calcium responses of cultured keratinocytes to external hydraulic pressure. First, we compared the responses of undifferentiated and differentiated keratinocytes with those of fibroblasts, vascular endothelial cells (VEC), and lymphatic endothelial cells. Elevation of intracellular calcium was observed after application of pressure to keratinocytes, fibroblasts, and VEC. The calcium propagation extended over a larger area and continued for a longer period of time in differentiated keratinocytes, as compared with the other cells. The response of the keratinocytes was dramatically reduced when the cells were incubated in medium without calcium. Application of a non-selective transient receptor potential (TRP) channel blocker also attenuated the calcium response. These results suggest that differentiated keratinocytes are sensitive to external pressure and that TRP might be involved in the mechanism of their response. (c) 2010 Wiley-Liss, Inc.

Determination of actual crop evapotranspiration (ETc) and dual crop coefficients (Kc) for cotton, wheat and maize in Fergana Valley: integration of the FAO-56 approach and BUDGET

NASA Astrophysics Data System (ADS)

Kenjabaev, Shavkat; Dernedde, Yvonne; Frede, Hans-Georg; Stulina, Galina

2014-05-01

Determination of the actual crop evapotranspiration (ETc) during the growing period is important for accurate irrigation scheduling in arid and semi-arid regions. Development of a crop coefficient (Kc) can enhance ETc estimations in relation to specific crop phenological development. This research was conducted to determine daily and growth-stage-specific Kc and ETc values for cotton (Gossypium hirsutum L.), winter wheat (Triticum aestivum L.) and maize (Zea mays L.) for silage at fields in Fergana Valley (Uzbekistan). The soil water balance model - Budget with integration of the dual crop procedure of the FAO-56 was used to estimate the ETc and separate it into evaporation (Ec) and transpiration (Tc) components. An empirical equation was developed to determine the daily Kc values based on the estimated Ec and Tc. The ETc, Kc determination and comparison to existing FAO Kc values were performed based on 10, 5 and 6 study cases for cotton, wheat and maize, respectively. Mean seasonal amounts of crop water consumption in terms of ETc were 560±50, 509±27 and 243±39 mm for cotton, wheat and maize, respectively. The growth-stage-specific Kc for cotton, wheat and maize was 0.15, 0.27 and 0.11 at initial; 1.15, 1.03 and 0.56 at mid; and 0.45, 0.89 and 0.53 at late season stages. These values correspond to those reported by the FAO-56. Development of site specific Kc helps tremendously in irrigation management and furthermore provides precise water applications in the region. The developed simple approach to estimate daily Kc for the three main crops grown in the Fergana region was a first attempt to meet this issue. Keywords: Actual crop evapotranspiration, evaporation and transpiration, crop coefficient, model BUDGET, Fergana Valley.

In vitro toxicity of photodynamic antimicrobial chemotherapy on human keratinocytes proliferation.

PubMed

Migliario, Mario; Rizzi, Manuela; Rocchetti, Vincenzo; Cannas, Mario; Renò, Filippo

2013-02-01

This in vitro experimental study has been designed to assess the effects of photodynamic antimicrobial chemotherapy (PACT) on human keratinocytes proliferation. Human keratinocytes (HaCaT) monolayers (∼0.5 cm(2)) have been irradiated with 635 nm red laser light with a fluence of 82.5 or 112.5 J/cm(2) in the absence or presence of toluidine (TB). Cell proliferation, monolayer area coverage, cytokeratin 5 (K5) and filaggrin (Fil) expression, and metalloproteinase (MMP)-2 and MMP-9 activity were measured after 72 h from laser irradiation. HaCaT proliferation was reduced by TB staining. Cell exposure to both low- and high-fluence laser irradiation in both presence and absence of TB staining reduced their proliferation and monolayer area extension. Moreover both laser treatments were able to reduce K5 and Fil expression and MMP-9 production in keratinocytes not treated with TB. These data indicate that PACT could exert toxic effects on normal proliferating keratinocytes present around parodontal pockets. The observed reduced cell proliferation along with a reduced production of enzymes involved in wound healing could alter the clinical outcome of the patients treated with PACT.

MiR-217 is down-regulated in psoriasis and promotes keratinocyte differentiation via targeting GRHL2

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

Zhu, Haigang; Hou, Liyue; Liu, Jingjing

MiR-217 is a well-known tumor suppressor, and its down-regulation has been shown in a wide range of solid and leukaemic cancers. However, the biological role of miR-217 in psoriasis pathogenesis, especially in keratinocyte hyperproliferation and differentiation, is not clearly understood. In this study, we found the expression of miR-217 was markedly down-regulated in psoriasis keratinocytes of psoriatic patients. In addition, overexpression of miR-217 inhibited the proliferation and promoted the differentiation of primary human keratinocytes. On the contrary, inhibition of endogenous miR-217 increased cell proliferation and delayed differentiation. Furthermore, Grainyhead-like 2 (GRHL2) was identified as a direct target of miR-217 bymore » luciferase reporter assay. The expression of miR-217 and GRHL2 was inversely correlated in both transfected keratinocytes and in psoriasis lesional skin. Moreover, knocking down GRHL2 expression by siRNA enhanced keratinocyte differentiation. Taken together, our results demonstrate a role for miR-217 in the regulation of keratinocyte differentiation, partially through the regulation of GRHL2. - Highlights: • miR-217 is down-regulated in psoriasis skin lesions. • miR-217 inhibits the proliferation and promotes differentiation of keratinocytes. • GRHL2 is a novel target of miR-217 in keratinocytes. • GRHL2 is up-regulated and inversely correlated with miR-217 in psoriasis skin lesions.« less

Integrin-Linked Kinase Is Indispensable for Keratinocyte Differentiation and Epidermal Barrier Function.

PubMed

Sayedyahossein, Samar; Rudkouskaya, Alena; Leclerc, Valerie; Dagnino, Lina

2016-02-01

A functional permeability barrier is essential to prevent the passage of water and electrolytes, macromolecules, and pathogens through the epidermis. This is accomplished in terminally differentiated keratinocytes through formation of a cornified envelope and the assembly of tight intercellular junctions. Integrin-linked kinase (ILK) is a scaffold protein essential for hair follicle morphogenesis and epidermal attachment to the basement membrane. However, the biological functions of ILK in differentiated keratinocytes remain poorly understood. Furthermore, whether ILK is implicated in keratinocyte differentiation and intercellular junction formation has remained an unresolved issue. Here we describe a pivotal role for ILK in keratinocyte differentiation responses to increased extracellular Ca(2+), regulation of adherens and tight junction assembly, and the formation of an outside-in permeability barrier toward macromolecules. In the absence of ILK, the calcium sensing receptor, E-cadherin, and ZO-1 fail to translocate to the cell membrane, through mechanisms that involve abnormalities in microtubules and in RhoA activation. In situ, ILK-deficient epidermis exhibits reduced tight junction formation and increased outside-in permeability to a dextran tracer, indicating reduced barrier properties toward macromolecules. Therefore, ILK is an essential component of keratinocyte differentiation programs that contribute to epidermal integrity and the establishment of its barrier properties. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Inflammatory cytokine and chemokine profiles are associated with patient outcome and the hyperadrenergic state following acute brain injury.

PubMed

Di Battista, Alex P; Rhind, Shawn G; Hutchison, Michael G; Hassan, Syed; Shiu, Maria Y; Inaba, Kenji; Topolovec-Vranic, Jane; Neto, Antonio Capone; Rizoli, Sandro B; Baker, Andrew J

2016-02-16

Traumatic brain injury (TBI) elicits intense sympathetic nervous system (SNS) activation with profuse catecholamine secretion. The resultant hyperadrenergic state is linked to immunomodulation both within the brain and systemically. Dysregulated inflammation post-TBI exacerbates secondary brain injury and contributes to unfavorable patient outcomes including death. The aim of this study was to characterize the early dynamic profile of circulating inflammatory cytokines/chemokines in patients admitted for moderate-to-severe TBI, to examine interrelationships between these mediators and catecholamines, as well as clinical indices of injury severity and neurological outcome. Blood was sampled from 166 isolated TBI patients (aged 45 ± 20.3 years; 74.7 % male) on admission, 6-, 12-, and 24-h post-injury and from healthy controls (N = 21). Plasma cytokine [interleukin (IL)-1β, -2, -4, -5, -10, -12p70, -13, tumor necrosis factor (TNF)-α, interferon (IFN)-γ] and chemokine [IL-8, eotaxin, eotaxin-3, IFN-γ-induced protein (IP)-10, monocyte chemoattractant protein (MCP)-1, -4, macrophage-derived chemokine (MDC), macrophage inflammatory protein (MIP)-1β, thymus activation regulated chemokine (TARC)] concentrations were analyzed using high-sensitivity electrochemiluminescence multiplex immunoassays. Plasma catecholamines [epinephrine (Epi), norepinephrine (NE)] were measured by immunoassay. Neurological outcome at 6 months was assessed using the extended Glasgow outcome scale (GOSE) dichotomized as good (>4) or poor (≤4) outcomes. Patients showed altered levels of IL-10 and all chemokines assayed relative to controls. Significant differences in a number of markers were evident between moderate and severe TBI cohorts. Elevated IL-8, IL-10, and TNF-α, as well as alterations in 8 of 9 chemokines, were associated with poor outcome at 6 months. Notably, a positive association was found between Epi and IL-1β, IL-10, Eotaxin, IL-8, and MCP-1. NE was positively associated

UVB light upregulates prostaglandin synthases and prostaglandin receptors in mouse keratinocytes

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

Black, Adrienne T.; Gray, Joshua P.; Shakarjian, Michael P.

Prostaglandins belong to a class of cyclic lipid-derived mediators synthesized from arachidonic acid via COX-1, COX-2 and various prostaglandin synthases. Members of this family include prostaglandins such as PGE{sub 2}, PGF{sub 2{alpha}}, PGD{sub 2} and PGI{sub 2} (prostacyclin) as well as thromboxane. In the present studies we analyzed the effects of UVB on prostaglandin production and prostaglandin synthase expression in primary cultures of undifferentiated and calcium-differentiated mouse keratinocytes. Both cell types were found to constitutively synthesize PGE{sub 2}, PGD{sub 2} and the PGD{sub 2} metabolite PGJ{sub 2}. Twenty-four hours after treatment with UVB (25 mJ/cm{sup 2}), production of PGE{sub 2}more » and PGJ{sub 2} increased, while PGD{sub 2} production decreased. This was associated with increased expression of COX-2 mRNA and protein. UVB (2.5-25 mJ/cm{sup 2}) also caused marked increases in mRNA expression for the prostanoid synthases PGDS, mPGES-1, mPGES-2, PGFS and PGIS, as well as expression of receptors for PGE{sub 2} (EP1 and EP2), PGD{sub 2} (DP and CRTH2) and prostacyclin (IP). UVB was more effective in inducing COX-2 and DP in differentiated cells and EP1 and IP in undifferentiated cells. UVB readily activated keratinocyte PI-3-kinase (PI3K)/Akt, JNK and p38 MAP signaling pathways which are known to regulate COX-2 expression. While inhibition of PI3K suppressed UVB-induced mPGES-1 and CRTH2 expression, JNK inhibition suppressed mPGES-1, PGIS, EP2 and CRTH2, and p38 kinase inhibition only suppressed EP1 and EP2. These data indicate that UVB modulates expression of prostaglandin synthases and receptors by distinct mechanisms. Moreover, both the capacity of keratinocytes to generate prostaglandins and their ability to respond to these lipid mediators are stimulated by exposure to UVB.« less

Immune receptors CD40 and CD86 in oral keratinocytes and implications for oral lichen planus.

PubMed

Marshall, Alison; Celentano, Antonio; Cirillo, Nicola; Mirams, Michiko; McCullough, Michael; Porter, Stephen

2017-01-01

Lichen planus (LP) is a chronic T-cell-mediated mucocutaneous inflammatory disease that targets stratified epithelia, including those lining the oral cavity. The intraoral variant of LP (OLP) is associated with interferon (IFN)-γ production by infiltrating T lymphocytes; however, the role of epithelial cells in the etiopathogenesis OLP is not completely understood. There is however a growing body of evidence regarding the involvement of epithelial-derived cytokines, immune receptors, and costimulatory molecules in the pathobiological processes that promote and sustain OLP. In the present study, we used a reverse transcriptase-polymerase chain reaction assay to assess whether CD40-a receptor found mainly on antigen presenting cells-and the costimulatory molecule CD86 were expressed in oral keratinocytes (three strains of primary normal oral keratinocytes and the H357 cell line) in the presence or absence of IFN-γ. To further characterize the involvement of CD40 in OLP, expression and distribution of receptor and ligand (CD40/CD154) in tissues from OLP were evaluated by immunohistochemistry. The present results are the first to show that both CD40 and CD86 are constitutively expressed at low levels in oral keratinocytes and that their expression was enhanced by IFN-γ stimulation. The intensity of CD40 staining in OLP tissues was strong. Taken together, the results strongly suggest that CD40 and CD86 play a role in the pathophysiology of oral inflammatory diseases such as OLP.

Dynamic switching mechanisms of a CC chemokine, CCL5 (RANTES). A simulation study

NASA Astrophysics Data System (ADS)

Peter, Emanuel; Pivkin, Igor

CCL5 (RANTES) belongs to the class of pro-inflammatory chemokines which are part of the human immune-response. It is known to activate leukocytes through its associated chemokine receptor 5 (CCR5) and plays a key role in several malignancies, including HIV-1 infections and cancer. In this talk, we present our results from enhanced sampling simulations of the CCL5 (RANTES) monomer. We find that this protein can adopt 2 different conformations : a globular form, with an orthogonal alignment of the N-terminal part, and a 'cis' form, in which the N-terminus is aligned parallel to the β-strand interface. A detailed analysis of the structure reveals that each of these states is stabilized by salt-bridges along the sequence, and corresponds to a defined dihedral-geometry of the 2 disulfide bridges Cys10-34 and Cys11-50. We derive a uniform distribution of transitions from the globular form of CCL5 (RANTES), and find that each of the main conformers adopts different electrostatic patterns.

The Galvanotactic Migration of Keratinocytes is Enhanced by Hypoxic Preconditioning

PubMed Central

Guo, Xiaowei; Jiang, Xupin; Ren, Xi; Sun, Huanbo; Zhang, Dongxia; Zhang, Qiong; Zhang, Jiaping; Huang, Yuesheng

2015-01-01

The endogenous electric field (EF)-directed migration of keratinocytes (galvanotaxis) into wounds is an essential step in wound re-epithelialization. Hypoxia, which occurs immediately after injury, acts as an early stimulus to initiate the healing process; however, the mechanisms for this effect, remain elusive. We show here that the galvanotactic migration of keratinocytes was enhanced by hypoxia preconditioning as a result of the increased directionality rather than the increased motility of keratinocytes. This enhancement was both oxygen tension- and preconditioning time-dependent, with the maximum effects achieved using 2% O2 preconditioning for 6 hours. Hypoxic preconditioning (2% O2, 6 hours) decreased the threshold voltage of galvanotaxis to < 25 mV/mm, whereas this value was between 25 and 50 mV/mm in the normal culture control. In a scratch-wound monolayer assay in which the applied EF was in the default healing direction, hypoxic preconditioning accelerated healing by 1.38-fold compared with the control conditions. Scavenging of the induced ROS by N-acetylcysteine (NAC) abolished the enhanced galvanotaxis and the accelerated healing by hypoxic preconditioning. Our data demonstrate a novel and unsuspected role of hypoxia in supporting keratinocyte galvanotaxis. Enhancing the galvanotactic response of cells might therefore be a clinically attractive approach to induce improved wound healing. PMID:25988491

Oxidative damage in keratinocytes exposed to cigarette smoke and aldehydes.

PubMed

Avezov, Katia; Reznick, Abraham Z; Aizenbud, Dror

2014-06-01

Cigarette smoke (CS) is a significant environmental source of human exposure to chemically active saturated (acetaldehyde) and α,β-unsaturated aldehydes (acrolein) inducing protein carbonylation and dysfunction. The exposure of oral tissues to environmental hazards is immense, especially in smokers. The objectives of the current study were to examine the effect of aldehydes originating from CS on intracellular proteins of oral keratinocytes and to observe the antioxidant response in these cells. Intracellular protein carbonyl modification under CS, acrolein and acetaldehyde exposure in the HaCaT keratinocyte cell line, representing oral keratinocytes was examined by Western blot. Possible intracellular enzymatic dysfunction under the above conditions was examined by lactate dehydrogenase (LDH) activity assay. Oxidative stress response was investigated, by DCF (2,7-dichlorodihydrofluorescein) assay and GSH (glutathione) oxidation. Intracellular protein carbonyls increased 5.2 times after CS exposure and 2.7 times after exposure to 1 μmol of acrolein. DCF assay revealed an increase of fluorescence intensity 3.2 and 3.1 times after CS and acrolein exposure, respectively. CS caused a 72.5% decrease in intracellular GSH levels compared to controls. Activity of intracellular LDH was preserved. α,β-Unsaturated aldehydes from CS are capable of intracellular protein carbonylation and have a role in intracellular oxidative stress elevation in keratinocytes, probably due to the reduction in GSH levels. Copyright © 2014 Elsevier Ltd. All rights reserved.

Modifications to the rapid melt/rapid quench and transparent polymer video furnaces for the KC-135

NASA Technical Reports Server (NTRS)

Smith, Guy A.; Kosten, Sue E.; Workman, Gary L.

1990-01-01

Given here is a summary of tasks performed on two furnace systems, the Transparent Polymer (TPF) and the Rapid Melt/Rapid Quench (RMRQ) furnaces, to be used aboard NASA's KC-135. It was determined that major changes were needed for both furnaces to operate according to the scientific investigators' experiment parameters. Discussed here are what the problems were, what was required to solve the problems, and possible future enhancements. It was determined that the enhancements would be required for the furnaces to perform at their optimal levels. Services provided include hardware and software modifications, Safety DataPackage documentation, ground based testing, transportation to and from Ellington Air Field, operation of hardware during KC-135 flights, and post-flight data processing.

Keratinocytes mediate innocuous and noxious touch via ATP-P2X4 signaling

PubMed Central

Moehring, Francie; Cowie, Ashley M; Menzel, Anthony D; Weyer, Andy D; Grzybowski, Michael; Arzua, Thiago; Geurts, Aron M; Palygin, Oleg

2018-01-01

The first point of our body’s contact with tactile stimuli (innocuous and noxious) is the epidermis, the outermost layer of skin that is largely composed of keratinocytes. Here, we sought to define the role that keratinocytes play in touch sensation in vivo and ex vivo. We show that optogenetic inhibition of keratinocytes decreases behavioral and cellular mechanosensitivity. These processes are inherently mediated by ATP signaling, as demonstrated by complementary cutaneous ATP release and degradation experiments. Specific deletion of P2X4 receptors in sensory neurons markedly decreases behavioral and primary afferent mechanical sensitivity, thus positioning keratinocyte-released ATP to sensory neuron P2X4 signaling as a critical component of baseline mammalian tactile sensation. These experiments lay a vital foundation for subsequent studies into the dysfunctional signaling that occurs in cutaneous pain and itch disorders, and ultimately, the development of novel topical therapeutics for these conditions. PMID:29336303

The effect of different biologic and biosynthetic wound covers on keratinocyte growth, stratification and differentiation in vitro

PubMed Central

Mestak, Ondrej

2014-01-01

The purpose of this study was to compare, by means of in vitro cultivation technique, five marketed brands of wound covers used in the treatment of burns and other skin defects (Biobrane®, Suprathel®, Veloderm®, Xe-Derma®, and Xenoderm®) for their ability to stimulate the keratinocyte growth, stratification, and differentiation. In three independent experiments, human keratinocytes were grown on the tested covers in organotypic cultures by the 3T3 feeder layer technique. Vertical paraffin sections of the wound covers with keratinocytes were processed using hematoxylin–eosin staining and immunostaining for involucrin. Keratinocyte populations on the dressings were assessed for (1) number of keratinocyte strata (primary variable), (2) quantitative growth, (3) thickness of the keratinocyte layer, and (4) cell differentiation. The Xe-Derma wound cover provided the best support to keratinocyte proliferation and stratification, with the number of keratinocyte strata significantly (p < 0.05) higher in comparison to all products studied, except Xenoderm. However, in contrast to Xe-Derma, Xenoderm did not significantly differ from the other dressings. The results of this in vitro study show that the brands based on porcine dermal matrix possess the strongest effect on keratinocyte proliferation and stratification. The distinctive position of Xe-Derma may be related to its composition, where natural dermal fibers form a smooth surface, similar to the basement membrane. Furthermore, the results indicate that in vitro evaluation of effects on epithelial growth may accelerate the development of new bio-engineering-based wound covers. PMID:25383177

Lipid deregulation in UV irradiated skin cells: Role of 25-hydroxycholesterol in keratinocyte differentiation during photoaging.

PubMed

Olivier, Elodie; Dutot, Mélody; Regazzetti, Anne; Dargère, Delphine; Auzeil, Nicolas; Laprévote, Olivier; Rat, Patrice

2017-05-01

Skin photoaging due to UV irradiation is a degenerative process that appears more and more as a growing concern. Lipids, including oxysterols, are involved in degenerative processes; as skin cells contain various lipids, the aim of our study was to evaluate first, changes in keratinocyte lipid levels induced by UV exposure and second, cellular effects of oxysterols in cell morphology and several hallmarks of keratinocyte differentiation. Our mass spectrometry results demonstrated that UV irradiation induces changes in lipid profile of cultured keratinocytes; in particular, ceramides and oxysterols, specifically 25-hydroxycholesterol (25-OH), were increased. Using holography and confocal microscopy analyses, we highlighted cell thickening and cytoskeletal disruption after incubation of keratinocytes with 25-OH. These alterations were associated with keratinocyte differentiation patterns: autophagy stimulation and intracellular calcium increase as measured by cytofluorometry, and increased involucrin level detected by immunocytochemistry. To conclude, oxysterol deregulation could be considered as a common marker of degenerative disorders. During photoaging, 25-OH seems to play a key role inducing morphological changes and keratinocyte differentiation. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Preparation and Analysis of N-Terminal Chemokine Receptor Sulfopeptides Using Tyrosylprotein Sulfotransferase Enzymes.

PubMed

Seibert, Christoph; Sanfiz, Anthony; Sakmar, Thomas P; Veldkamp, Christopher T

2016-01-01

In most chemokine receptors, one or multiple tyrosine residues have been identified within the receptor N-terminal domain that are, at least partially, modified by posttranslational tyrosine sulfation. For example, tyrosine sulfation has been demonstrated for Tyr-3, -10, -14, and -15 of CCR5, for Tyr-3, -14, and -15 of CCR8, and for Tyr-7, -12, and -21 of CXCR4. While there is evidence for several chemokine receptors that tyrosine sulfation is required for optimal interaction with the chemokine ligands, the precise role of tyrosine sulfation for chemokine receptor function remains unclear. Furthermore, the function of the chemokine receptor N-terminal domain in chemokine binding and receptor activation is also not well understood. Sulfotyrosine peptides corresponding to the chemokine receptor N-termini are valuable tools to address these important questions both in structural and functional studies. However, due to the lability of the sulfotyrosine modification, these peptides are difficult to obtain using standard peptide chemistry methods. In this chapter, we provide methods to prepare sulfotyrosine peptides by enzymatic in vitro sulfation of peptides using purified recombinant tyrosylprotein sulfotransferase (TPST) enzymes. In addition, we also discuss alternative approaches for the generation of sulfotyrosine peptides and methods for sulfopeptide analysis. © 2016 Elsevier Inc. All rights reserved.

Preparation and analysis of N-terminal chemokine receptor sulfopeptides using tyrosylprotein sulfotransferase enzymes

PubMed Central

Seibert, Christoph; Sanfiz, Anthony; Sakmar, Thomas P.; Veldkamp, Christopher T.

2016-01-01

In most chemokine receptors, one or multiple tyrosine residues have been identified within the receptor N-terminal domain that are, at least partially, modified by post-translational tyrosine sulfation. For example, tyrosine sulfation has been demonstrated for Tyr-3, -10, -14, and -15 of CCR5, for Tyr-3, -14, and -15 of CCR8 and for Tyr-7, -12, and -21 of CXCR4. While there is evidence for several chemokine receptors that tyrosine sulfation is required for optimal interaction with the chemokine ligands, the precise role of tyrosine sulfation for chemokine receptor function remains unclear. Furthermore, the function of the chemokine receptor N-terminal domain in chemokine binding and receptor activation is also not well understood. Sulfotyrosine peptides corresponding to the chemokine receptor N-termini are valuable tools to address these important questions both in structural and functional studies. However, due to the liability of the sulfotyrosine modification, these peptides are difficult to obtain using standard peptide chemistry methods. In this chapter, we provide methods to prepare sulfotyrosine peptides by enzymatic in vitro sulfation of peptides using purified recombinant tyrosylprotein sulfotransferase (TPST) enzymes. In addition, we also discuss alternative approaches for the generation of sulfotyrosine peptides and methods from sulfopeptide analysis. PMID:26921955

Pimecrolimus Enhances TLR2/6-Induced Expression of Antimicrobial Peptides in Keratinocytes

PubMed Central

Büchau, Amanda S.; Schauber, Jürgen; Hultsch, Thomas; Stuetz, Anton; Gallo, Richard L.

2009-01-01

Calcineurin inhibitors are potent inhibitors of T-cell-receptor mediated activation of the adaptive immune system. The effects of this class of drug on the innate immune response system are not known. Keratinocytes are essential to innate immunity in skin and rely on toll-like receptors (TLRs) and antimicrobial peptides to appropriately recognize and respond to injury or microbes. In this study we examined the response of cultured human keratinocytes to pimecrolimus. We observed that pimecrolimus enhances distinct expression of cathelicidin, CD14, and human β-defensin-2 and β-defensin-3 in response to TLR2/6 ligands. Some of these responses were further enhanced by 1,25 vitamin D3. Pimecrolimus also increased the functional capacity of keratinocytes to inhibit growth of Staphylococcus aureusand decreased TLR2/6-induced expression of IL-10 and IL-1β. Furthermore, pimecrolimus inhibited nuclear translocation of NFAT and NF-κB in keratinocytes. These observations uncover a previously unreported function for pimecrolimus in cutaneous innate host defense. PMID:18496569

Hypobaric Hypoxia Exacerbates the Neuroinflammatory Response to Traumatic Brain Injury

PubMed Central

Goodman, Michael D.; Makley, Amy T.; Huber, Nathan L.; Clarke, Callisia N.; Friend, Lou Ann W.; Schuster, Rebecca M.; Bailey, Stephanie R.; Barnes, Stephen L.; Dorlac, Warren C.; Johannigman, Jay A.; Lentsch, Alex B.; Pritts, Timothy A.

2015-01-01

Objective To determine the inflammatory effects of time-dependent exposure to the hypobaric environment of simulated aeromedical evacuation following traumatic brain injury (TBI). Methods Mice were subjected to a blunt TBI or sham injury. Righting reflex response (RRR) time was assessed as an indicator of neurologic recovery. Three or 24 h (Early and Delayed groups, respectively) after TBI, mice were exposed to hypobaric flight conditions (Fly) or ground-level control (No Fly) for 5 h. Arterial blood gas samples were obtained from all groups during simulated flight. Serum and cortical brain samples were analyzed for inflammatory cytokines after flight. Neuron specific enolase (NSE) was measured as a serum biomarker of TBI severity. Results TBI resulted in prolonged RRR time compared with sham injury. After TBI alone, serum levels of interleukin-6 (IL-6) and keratinocyte-derived chemokine (KC) were increased by 6 h post-injury. Simulated flight significantly reduced arterial oxygen saturation levels in the Fly group. Post-injury altitude exposure increased cerebral levels of IL-6 and macrophage inflammatory protein-1α (MIP-1α), as well as serum NSE in the Early but not Delayed Flight group compared to ground-level controls. Conclusions The hypobaric environment of aero-medical evacuation results in significant hypoxia. Early, but not delayed, exposure to a hypobaric environment following TBI increases the neuroinflammatory response to injury and the severity of secondary brain injury. Optimization of the post-injury time to fly using serum cytokine and biomarker levels may reduce the potential secondary cerebral injury induced by aeromedical evacuation. PMID:20850781

Activation of T-cell Protein-tyrosine Phosphatase Suppresses Keratinocyte Survival and Proliferation following UVB Irradiation*

PubMed Central

Lee, Hyunseung; Morales, Liza D.; Slaga, Thomas J.; Kim, Dae Joon

2015-01-01

Chronic exposure to UV radiation can contribute to the development of skin cancer by promoting protein-tyrosine kinase (PTK) signaling. Studies show that exposure to UV radiation increases the ligand-independent activation of PTKs and induces protein-tyrosine phosphatase (PTP) inactivation. In the present work, we report that T-cell PTP (TC-PTP) activity is stimulated during the initial response to UVB irradiation, which leads to suppression of keratinocyte cell survival and proliferation via the down-regulation of STAT3 signaling. Our results show that TC-PTP-deficient keratinocyte cell lines expressed a significantly increased level of phosphorylated STAT3 after exposure to low dose UVB. This increase corresponded with increased cell proliferation in TC-PTP-deficient keratinocytes following UVB irradiation. Loss of TC-PTP also reduced UVB-induced apoptosis. Corroborating with these results, overexpression of TC-PTP in keratinocyte cell lines yielded a decrease in phosphorylated STAT3 levels, which corresponded with a significant decrease in cell proliferation in response to low dose UVB. We demonstrate that TC-PTP activity was increased upon UVB exposure, and overexpression of TC-PTP in keratinocyte cell lines further increased its activity in the presence of UVB. Treatment of TC-PTP-deficient keratinocytes with the STAT3 inhibitor STA21 significantly reduced cell viability following UVB exposure in comparison with untreated TC-PTP-deficient keratinocytes, confirming that the effect of TC-PTP on cell viability is mediated by STAT3 dephosphorylation. Combined, our results indicate that UVB-mediated activation of TC-PTP plays an important role in the STAT3-dependent regulation of keratinocyte cell proliferation and survival. Furthermore, these results suggest that TC-PTP may be a novel potential target for the prevention of UVB-induced skin cancer. PMID:25406309