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Fabrice Allain - One of the best experts on this subject based on the ideXlab platform.
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HEMOSTASIS, THROMBOSIS, AND VASCULAR BIOLOGY <B>CyclophilinB> B Binding to Platelets Supports Calcium-Dependent Adhesion to Collagen
2016Co-Authors: Fabrice Allain, Mathieu Carpentier, Sandrine Durieux, Geneviève SpikAbstract:We have recently reported that <B>CyclophilinB> B (CyPB), a secreted cyclosporine-Binding protein, could Bind to T lymphocytes through interactions with two types of Binding sites. The first ones, referred to as type I, involve interactions with the conserved domain of CyPB and promote the endocytosis of surface-Bound ligand, while the second type of Binding sites, termed type II, are represented By glycosaminoglycans (GAG). Here, we further investigated the interactions of CyPB with Blood cell populations. In addition to lymphocytes, CyPB was found to interact mainly with platelets. The Binding is specific, with a dissociation constant (kd) of 9 6 3 nmol/L and the numBer of sites estimated at 960 6 60 per cell. Platelet glycosaminoglycans are not required for the interactions, But the Binding is dramatically reduced By active cyclosporine derivatives. We then analyzed the Biologic effects of CyPB and found a significant increase in platelet adhesion to collagen. Concurrently, CyPB initiates a transmemBranous influx of Ca21 and induces the phosphorylation of the P-20 light chains of myosin. Taken together, the present results demonstrate for the first time that extracellular CyPB specifically interacts with platelets through a functional receptor related to the lymphocyte type I Binding sites and might act By regulating the activity of a receptor-operated memBrane Ca21 channel.
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Keratinocyte Secretion of <B>CyclophilinB> B via the Constitutive Pathway Is Regulated through Its Cyclosporin-Binding Site
The Journal of investigative dermatology, 2011Co-Authors: P Fearon, Fabrice Allain, Ann A. Lonsdale-eccles, O. Kehinde Ross, Carole Todd, Aparna Sinha, Nick J. ReynoldsAbstract:<B>CyclophilinB> B (CypB) is an endoplasmic reticulum (ER)-resident memBer of the <B>CyclophilinB> family of proteins that Bind cyclosporin A (CsA). We report that as in other cell types, CypB trafficked from the ER and was secreted By keratinocytes into the media in response to CsA. Concentrations as low as 1pM of CsA induced secretion of CypB. Using Brefeldin A, we showed that CypB is secreted from keratinocytes via the constitutive secretory pathway. We defined that suBstitution of tryptophan residue 128 in the CsA-Binding site of CypB with alanine resulted in dissociation of CypB W128A -green fluorescent protein (GFP) from the ER. PhotoBleaching studies revealed a significant reduction in the diffusiBle moBility of CypB W128A -GFP compared with CypB WT -GFP, consistent with redistriBution of CypB W128A -GFP into secretory vesicles disconnected from the ER/Golgi network. Furthermore, CsA significantly decreased the moBility of CypB WT -GFP But not CypB W128A -GFP. These studies demonstrate that therapeutically relevant concentrations of CsA regulate secretion of CypB By keratinocytes, and that a key residue within the CsA-Binding site of CypB controls retention of CypB within the ER and regulates entry into the secretory pathway. As keratinocytes express CypB receptors (CD147) and CypB exhiBits chemotactic properties, these data have implications for the therapeutic effects of CsA in inflammatory skin disease.
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Synthesis of Heparan Sulfate with <B>CyclophilinB> B-Binding Properties Is Determined By Cell Type-specific Expression of Sulfotransferases
The Journal of biological chemistry, 2009Co-Authors: Audrey Deligny, Agnès Denys, Joël Mazurier, Aurélie Melchior, Adeline Marcant, Toin H. Van Kuppevelt, Fabrice AllainAbstract:<B>CyclophilinB> B (CyPB) induces migration and adhesion of T lymphocytes via a mechanism that requires interaction with 3-O-sulfated heparan sulfate (HS). HS Biosynthesis is a complex process with many sulfotransferases involved. N-Deacetylases/N-sulfotransferases are responsiBle for N-sulfation, which is essential for suBsequent modification steps, whereas 3-O-sulfotransferases (3-OSTs) catalyze the least aBundant modification. These enzymes are represented By several isoforms, which differ in term of distriBution pattern, suggesting their involvement in making tissue-specific HS. To elucidate how the specificity of CyPB Binding is determined, we explored the relationships Between the expression of these sulfotransferases and the generation of HS motifs with CyPB-Binding properties. We demonstrated that high N-sulfate density and the presence of 2-O- and 3-O-sulfates determine Binding of CyPB, as evidenced By competitive experiments with heparin derivatives, soluBle HS, and anti-HS antiBodies. We then showed that target cells, i.e. CD4+ lymphocyte suBsets, monocytes/macrophages, and related cell lines, specifically expressed high levels of NDST2 and 3-OST3 isoforms. Silencing the expression of NDST1, NDST2, 2-OST, and 3-OST3 By RNA interference efficiently decreased Binding and activity of CyPB, thus confirming their involvement in the Biosynthesis of Binding sequences for CyPB. Moreover, we demonstrated that NDST1 was aBle to partially sulfate exogenous suBstrate in the aBsence of NDST2 But not vice versa, suggesting that Both isoenzymes do not have redundant activities But do have rather complementary activities in making N-sulfated sequences with CyPB-Binding properties. Altogether, these results suggest a regulatory mechanism in which cell type-specific expression of certain HS sulfotransferases determines the specific Binding of CyPB to target cells.
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<B>CyclophilinB> B induces integrin-mediated cell adhesion By a mechanism involving CD98-dependent activation of protein kinase C-delta and p44/42 mitogen-activated protein kinases.
Experimental Cell Research, 2007Co-Authors: Aurélie Melchior, Agnès Denys, Joël Mazurier, Audrey Deligny, Fabrice AllainAbstract:Initially identified as a cyclosporin-A Binding protein, <B>CyclophilinB> B (CyPB) is an inflammatory mediator that induces adhesion of T lymphocytes to fiBronectin, By a mechanism dependent on CD147 and alpha4Beta1 integrins. Recent findings have suggested that another cell memBrane protein, CD98, may cooperate with CD147 to regulate Beta1 integrin functions. Based on these functional relationships, we examined the contriBution of CD98 in the pro-adhesive activity of CyPB, By utilizing the responsive promonocyte cell line THP-1. We demonstrated that cross-linking CD98 with CD98-AHN-18 antiBody mimicked the responses induced By CyPB, i.e. homotypic aggregation, integrin-mediated adhesion to fiBronectin and activation of p44/42 MAPK. Consistent with previous data, immunoprecipitation confirmed the existence of a heterocomplex wherein CD147, CD98 and Beta1 integrins were associated. We then demonstrated that CyPB-induced cell adhesion and p44/42 MAPK activation were dependent on the participation of phosphoinositide 3-kinase and suBsequent activation of protein kinase C-delta. Finally, silencing the expression of CD98 By RNA interference potently reduced CyPB-induced cell responses, thus confirming the role of CD98 in the pro-adhesive activity of CyPB. Altogether, our results support a model whereBy CyPB induces integrin-mediated adhesion via interaction with a multimolecular unit formed By the association Between CD147, CD98 and Beta1 integrins.
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<B>CyclophilinB> B induces integrin-mediated cell adhesion By a mechanism involving CD98-dependent activation of protein kinase C-delta and p44/42 mitogen-activated protein kinases.
Experimental cell research, 2007Co-Authors: Aurélie Melchior, Agnès Denys, Joël Mazurier, Audrey Deligny, Fabrice AllainAbstract:ABstract Initially identified as a cyclosporin-A Binding protein, <B>CyclophilinB> B (CyPB) is an inflammatory mediator that induces adhesion of T lymphocytes to fiBronectin, By a mechanism dependent on CD147 and α4β1 integrins. Recent findings have suggested that another cell memBrane protein, CD98, may cooperate with CD147 to regulate β1 integrin functions. Based on these functional relationships, we examined the contriBution of CD98 in the pro-adhesive activity of CyPB, By utilizing the responsive promonocyte cell line THP-1. We demonstrated that cross-linking CD98 with CD98-AHN-18 antiBody mimicked the responses induced By CyPB, i.e. homotypic aggregation, integrin-mediated adhesion to fiBronectin and activation of p44/42 MAPK. Consistent with previous data, immunoprecipitation confirmed the existence of a heterocomplex wherein CD147, CD98 and β1 integrins were associated. We then demonstrated that CyPB-induced cell adhesion and p44/42 MAPK activation were dependent on the participation of phosphoinositide 3-kinase and suBsequent activation of protein kinase C-δ. Finally, silencing the expression of CD98 By RNA interference potently reduced CyPB-induced cell responses, thus confirming the role of CD98 in the pro-adhesive activity of CyPB. Altogether, our results support a model whereBy CyPB induces integrin-mediated adhesion via interaction with a multimolecular unit formed By the association Between CD147, CD98 and β1 integrins.
Agnès Denys - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of Heparan Sulfate with <B>CyclophilinB> B-Binding Properties Is Determined By Cell Type-specific Expression of Sulfotransferases
The Journal of biological chemistry, 2009Co-Authors: Audrey Deligny, Agnès Denys, Joël Mazurier, Aurélie Melchior, Adeline Marcant, Toin H. Van Kuppevelt, Fabrice AllainAbstract:<B>CyclophilinB> B (CyPB) induces migration and adhesion of T lymphocytes via a mechanism that requires interaction with 3-O-sulfated heparan sulfate (HS). HS Biosynthesis is a complex process with many sulfotransferases involved. N-Deacetylases/N-sulfotransferases are responsiBle for N-sulfation, which is essential for suBsequent modification steps, whereas 3-O-sulfotransferases (3-OSTs) catalyze the least aBundant modification. These enzymes are represented By several isoforms, which differ in term of distriBution pattern, suggesting their involvement in making tissue-specific HS. To elucidate how the specificity of CyPB Binding is determined, we explored the relationships Between the expression of these sulfotransferases and the generation of HS motifs with CyPB-Binding properties. We demonstrated that high N-sulfate density and the presence of 2-O- and 3-O-sulfates determine Binding of CyPB, as evidenced By competitive experiments with heparin derivatives, soluBle HS, and anti-HS antiBodies. We then showed that target cells, i.e. CD4+ lymphocyte suBsets, monocytes/macrophages, and related cell lines, specifically expressed high levels of NDST2 and 3-OST3 isoforms. Silencing the expression of NDST1, NDST2, 2-OST, and 3-OST3 By RNA interference efficiently decreased Binding and activity of CyPB, thus confirming their involvement in the Biosynthesis of Binding sequences for CyPB. Moreover, we demonstrated that NDST1 was aBle to partially sulfate exogenous suBstrate in the aBsence of NDST2 But not vice versa, suggesting that Both isoenzymes do not have redundant activities But do have rather complementary activities in making N-sulfated sequences with CyPB-Binding properties. Altogether, these results suggest a regulatory mechanism in which cell type-specific expression of certain HS sulfotransferases determines the specific Binding of CyPB to target cells.
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<B>CyclophilinB> B induces integrin-mediated cell adhesion By a mechanism involving CD98-dependent activation of protein kinase C-delta and p44/42 mitogen-activated protein kinases.
Experimental Cell Research, 2007Co-Authors: Aurélie Melchior, Agnès Denys, Joël Mazurier, Audrey Deligny, Fabrice AllainAbstract:Initially identified as a cyclosporin-A Binding protein, <B>CyclophilinB> B (CyPB) is an inflammatory mediator that induces adhesion of T lymphocytes to fiBronectin, By a mechanism dependent on CD147 and alpha4Beta1 integrins. Recent findings have suggested that another cell memBrane protein, CD98, may cooperate with CD147 to regulate Beta1 integrin functions. Based on these functional relationships, we examined the contriBution of CD98 in the pro-adhesive activity of CyPB, By utilizing the responsive promonocyte cell line THP-1. We demonstrated that cross-linking CD98 with CD98-AHN-18 antiBody mimicked the responses induced By CyPB, i.e. homotypic aggregation, integrin-mediated adhesion to fiBronectin and activation of p44/42 MAPK. Consistent with previous data, immunoprecipitation confirmed the existence of a heterocomplex wherein CD147, CD98 and Beta1 integrins were associated. We then demonstrated that CyPB-induced cell adhesion and p44/42 MAPK activation were dependent on the participation of phosphoinositide 3-kinase and suBsequent activation of protein kinase C-delta. Finally, silencing the expression of CD98 By RNA interference potently reduced CyPB-induced cell responses, thus confirming the role of CD98 in the pro-adhesive activity of CyPB. Altogether, our results support a model whereBy CyPB induces integrin-mediated adhesion via interaction with a multimolecular unit formed By the association Between CD147, CD98 and Beta1 integrins.
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<B>CyclophilinB> B induces integrin-mediated cell adhesion By a mechanism involving CD98-dependent activation of protein kinase C-delta and p44/42 mitogen-activated protein kinases.
Experimental cell research, 2007Co-Authors: Aurélie Melchior, Agnès Denys, Joël Mazurier, Audrey Deligny, Fabrice AllainAbstract:ABstract Initially identified as a cyclosporin-A Binding protein, <B>CyclophilinB> B (CyPB) is an inflammatory mediator that induces adhesion of T lymphocytes to fiBronectin, By a mechanism dependent on CD147 and α4β1 integrins. Recent findings have suggested that another cell memBrane protein, CD98, may cooperate with CD147 to regulate β1 integrin functions. Based on these functional relationships, we examined the contriBution of CD98 in the pro-adhesive activity of CyPB, By utilizing the responsive promonocyte cell line THP-1. We demonstrated that cross-linking CD98 with CD98-AHN-18 antiBody mimicked the responses induced By CyPB, i.e. homotypic aggregation, integrin-mediated adhesion to fiBronectin and activation of p44/42 MAPK. Consistent with previous data, immunoprecipitation confirmed the existence of a heterocomplex wherein CD147, CD98 and β1 integrins were associated. We then demonstrated that CyPB-induced cell adhesion and p44/42 MAPK activation were dependent on the participation of phosphoinositide 3-kinase and suBsequent activation of protein kinase C-δ. Finally, silencing the expression of CD98 By RNA interference potently reduced CyPB-induced cell responses, thus confirming the role of CD98 in the pro-adhesive activity of CyPB. Altogether, our results support a model whereBy CyPB induces integrin-mediated adhesion via interaction with a multimolecular unit formed By the association Between CD147, CD98 and β1 integrins.
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Structural and functional characterization of the interaction Between <B>CyclophilinB> B and a heparin-derived oligosaccharide.
The Journal of biological chemistry, 2007Co-Authors: Xavier Hanoulle, Agnès Denys, Fabrice Allain, Aurélie Melchior, Nathalie Sibille, Benjamin Parent, Jean-michel Wieruszeski, Dragos Horvath, Guy Lippens, Isabelle LandrieuAbstract:ABstract The chemotaxis and integrin-mediated adhesion of T lymphocytes triggered By secreted <B>CyclophilinB> B (CypB) depend on interactions with Both cell surface heparan sulfate proteoglycans (HSPG) and the extracellular domain of the CD147 memBrane receptor. Here, we use NMR spectroscopy to characterize the interaction of CypB with heparin-derived oligosaccharides. Chemical shift perturBation experiments allowed the precise definition of the heparan sulfate (HS) Binding site of CypB. The N-terminal extremity of CypB, which contains a consensus sequence for heparin-Binding proteins was modeled on the Basis of our experimental NMR data. Because the HS Binding site extends toward the CypB catalytic pocket, we measured its peptidyl-prolyl cis-trans isomerase (PPIase) activity in the aBsence or presence of a HS oligosaccharide toward a CD147-derived peptide. We report the first direct evidence that CypB is enzymatically active on CD147, as it is aBle to accelerate the cis/trans isomerization of the Asp179-Pro180 Bond in a CD147-derived peptide. However, HS Binding has no significant influence on this PPIase activity. We thus conclude that the glycanic moiety of HSPG serves as anchor for CypB at the cell surface, and that the signal could Be transduced By CypB via its PPIase activity toward CD147.
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the heparin heparan sulfate sequence that interacts with <B>CyclophilinB> B contains a 3 o sulfated n unsuBstituted glucosamine residue
Journal of Biological Chemistry, 2007Co-Authors: Christophe Vanpouille, Agnès Denys, Joël Mazurier, Aurélie Melchior, Audrey Deligny, Maryse Delehedde, Malcolm Lyon, David G. Fernig, Xavier Liénard, Fabrice AllainAbstract:Many of the Biological functions of heparan sulfate (HS) proteoglycans can Be attriButed to specialized structures within HS moieties, which are thought to modulate Binding and function of various effector proteins. <B>CyclophilinB> B (CyPB), which was initially identified as a cyclosporin A-Binding protein, triggers migration and integrin-mediated adhesion of peripheral Blood T lymphocytes By a mechanism dependent on interaction with cell surface HS. Here we determined the structural features of HS that are responsiBle for the specific Binding of CyPB. In addition to the involvement of 2-O,6-O, and N-sulfate groups, we also demonstrated that Binding of CyPB was dependent on the presence of N-unsuBstituted glucosamine residues (GlcNH2), which have Been reported to Be precursors for sulfation By 3-O-sulfotransferases-3 (3-OST-3). Interestingly, 3-OST-3B isoform was found to Be the main 3-OST isoenzyme expressed in peripheral Blood T lymphocytes and Jurkat T cells. Moreover, down-regulation of the expression of 3-OST-3 By RNA interference potently reduced CyPB Binding and consequent activation of p44/42 mitogen-activated protein kinases. Altogether, our results strongly support the hypothesis that 3-O-sulfation of GlcNH2 residues could Be a key modification that provides specialized HS structures for CyPB Binding to responsive cells. Given that 3-O-sulfation of GlcNH2-containing HS By 3-OST-3 also provides Binding sites for glycoprotein gD of herpes simplex virus type I, these findings suggest an intriguing structural linkage Between the HS sequences involved in CyPB Binding and viral infection.
Joël Mazurier - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of Heparan Sulfate with <B>CyclophilinB> B-Binding Properties Is Determined By Cell Type-specific Expression of Sulfotransferases
The Journal of biological chemistry, 2009Co-Authors: Audrey Deligny, Agnès Denys, Joël Mazurier, Aurélie Melchior, Adeline Marcant, Toin H. Van Kuppevelt, Fabrice AllainAbstract:<B>CyclophilinB> B (CyPB) induces migration and adhesion of T lymphocytes via a mechanism that requires interaction with 3-O-sulfated heparan sulfate (HS). HS Biosynthesis is a complex process with many sulfotransferases involved. N-Deacetylases/N-sulfotransferases are responsiBle for N-sulfation, which is essential for suBsequent modification steps, whereas 3-O-sulfotransferases (3-OSTs) catalyze the least aBundant modification. These enzymes are represented By several isoforms, which differ in term of distriBution pattern, suggesting their involvement in making tissue-specific HS. To elucidate how the specificity of CyPB Binding is determined, we explored the relationships Between the expression of these sulfotransferases and the generation of HS motifs with CyPB-Binding properties. We demonstrated that high N-sulfate density and the presence of 2-O- and 3-O-sulfates determine Binding of CyPB, as evidenced By competitive experiments with heparin derivatives, soluBle HS, and anti-HS antiBodies. We then showed that target cells, i.e. CD4+ lymphocyte suBsets, monocytes/macrophages, and related cell lines, specifically expressed high levels of NDST2 and 3-OST3 isoforms. Silencing the expression of NDST1, NDST2, 2-OST, and 3-OST3 By RNA interference efficiently decreased Binding and activity of CyPB, thus confirming their involvement in the Biosynthesis of Binding sequences for CyPB. Moreover, we demonstrated that NDST1 was aBle to partially sulfate exogenous suBstrate in the aBsence of NDST2 But not vice versa, suggesting that Both isoenzymes do not have redundant activities But do have rather complementary activities in making N-sulfated sequences with CyPB-Binding properties. Altogether, these results suggest a regulatory mechanism in which cell type-specific expression of certain HS sulfotransferases determines the specific Binding of CyPB to target cells.
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<B>CyclophilinB> B induces integrin-mediated cell adhesion By a mechanism involving CD98-dependent activation of protein kinase C-delta and p44/42 mitogen-activated protein kinases.
Experimental cell research, 2007Co-Authors: Aurélie Melchior, Agnès Denys, Joël Mazurier, Audrey Deligny, Fabrice AllainAbstract:ABstract Initially identified as a cyclosporin-A Binding protein, <B>CyclophilinB> B (CyPB) is an inflammatory mediator that induces adhesion of T lymphocytes to fiBronectin, By a mechanism dependent on CD147 and α4β1 integrins. Recent findings have suggested that another cell memBrane protein, CD98, may cooperate with CD147 to regulate β1 integrin functions. Based on these functional relationships, we examined the contriBution of CD98 in the pro-adhesive activity of CyPB, By utilizing the responsive promonocyte cell line THP-1. We demonstrated that cross-linking CD98 with CD98-AHN-18 antiBody mimicked the responses induced By CyPB, i.e. homotypic aggregation, integrin-mediated adhesion to fiBronectin and activation of p44/42 MAPK. Consistent with previous data, immunoprecipitation confirmed the existence of a heterocomplex wherein CD147, CD98 and β1 integrins were associated. We then demonstrated that CyPB-induced cell adhesion and p44/42 MAPK activation were dependent on the participation of phosphoinositide 3-kinase and suBsequent activation of protein kinase C-δ. Finally, silencing the expression of CD98 By RNA interference potently reduced CyPB-induced cell responses, thus confirming the role of CD98 in the pro-adhesive activity of CyPB. Altogether, our results support a model whereBy CyPB induces integrin-mediated adhesion via interaction with a multimolecular unit formed By the association Between CD147, CD98 and β1 integrins.
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<B>CyclophilinB> B induces integrin-mediated cell adhesion By a mechanism involving CD98-dependent activation of protein kinase C-delta and p44/42 mitogen-activated protein kinases.
Experimental Cell Research, 2007Co-Authors: Aurélie Melchior, Agnès Denys, Joël Mazurier, Audrey Deligny, Fabrice AllainAbstract:Initially identified as a cyclosporin-A Binding protein, <B>CyclophilinB> B (CyPB) is an inflammatory mediator that induces adhesion of T lymphocytes to fiBronectin, By a mechanism dependent on CD147 and alpha4Beta1 integrins. Recent findings have suggested that another cell memBrane protein, CD98, may cooperate with CD147 to regulate Beta1 integrin functions. Based on these functional relationships, we examined the contriBution of CD98 in the pro-adhesive activity of CyPB, By utilizing the responsive promonocyte cell line THP-1. We demonstrated that cross-linking CD98 with CD98-AHN-18 antiBody mimicked the responses induced By CyPB, i.e. homotypic aggregation, integrin-mediated adhesion to fiBronectin and activation of p44/42 MAPK. Consistent with previous data, immunoprecipitation confirmed the existence of a heterocomplex wherein CD147, CD98 and Beta1 integrins were associated. We then demonstrated that CyPB-induced cell adhesion and p44/42 MAPK activation were dependent on the participation of phosphoinositide 3-kinase and suBsequent activation of protein kinase C-delta. Finally, silencing the expression of CD98 By RNA interference potently reduced CyPB-induced cell responses, thus confirming the role of CD98 in the pro-adhesive activity of CyPB. Altogether, our results support a model whereBy CyPB induces integrin-mediated adhesion via interaction with a multimolecular unit formed By the association Between CD147, CD98 and Beta1 integrins.
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the heparin heparan sulfate sequence that interacts with <B>CyclophilinB> B contains a 3 o sulfated n unsuBstituted glucosamine residue
Journal of Biological Chemistry, 2007Co-Authors: Christophe Vanpouille, Agnès Denys, Joël Mazurier, Aurélie Melchior, Audrey Deligny, Maryse Delehedde, Malcolm Lyon, David G. Fernig, Xavier Liénard, Fabrice AllainAbstract:Many of the Biological functions of heparan sulfate (HS) proteoglycans can Be attriButed to specialized structures within HS moieties, which are thought to modulate Binding and function of various effector proteins. <B>CyclophilinB> B (CyPB), which was initially identified as a cyclosporin A-Binding protein, triggers migration and integrin-mediated adhesion of peripheral Blood T lymphocytes By a mechanism dependent on interaction with cell surface HS. Here we determined the structural features of HS that are responsiBle for the specific Binding of CyPB. In addition to the involvement of 2-O,6-O, and N-sulfate groups, we also demonstrated that Binding of CyPB was dependent on the presence of N-unsuBstituted glucosamine residues (GlcNH2), which have Been reported to Be precursors for sulfation By 3-O-sulfotransferases-3 (3-OST-3). Interestingly, 3-OST-3B isoform was found to Be the main 3-OST isoenzyme expressed in peripheral Blood T lymphocytes and Jurkat T cells. Moreover, down-regulation of the expression of 3-OST-3 By RNA interference potently reduced CyPB Binding and consequent activation of p44/42 mitogen-activated protein kinases. Altogether, our results strongly support the hypothesis that 3-O-sulfation of GlcNH2 residues could Be a key modification that provides specialized HS structures for CyPB Binding to responsive cells. Given that 3-O-sulfation of GlcNH2-containing HS By 3-OST-3 also provides Binding sites for glycoprotein gD of herpes simplex virus type I, these findings suggest an intriguing structural linkage Between the HS sequences involved in CyPB Binding and viral infection.
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The Heparin/Heparan Sulfate Sequence That Interacts with <B>CyclophilinB> B Contains a 3-O-Sulfated N-UnsuBstituted Glucosamine Residue
The Journal of biological chemistry, 2007Co-Authors: Christophe Vanpouille, Agnès Denys, Joël Mazurier, Aurélie Melchior, Audrey Deligny, Maryse Delehedde, Malcolm Lyon, David G. Fernig, Xavier Liénard, Fabrice AllainAbstract:Many of the Biological functions of heparan sulfate (HS) proteoglycans can Be attriButed to specialized structures within HS moieties, which are thought to modulate Binding and function of various effector proteins. <B>CyclophilinB> B (CyPB), which was initially identified as a cyclosporin A-Binding protein, triggers migration and integrin-mediated adhesion of peripheral Blood T lymphocytes By a mechanism dependent on interaction with cell surface HS. Here we determined the structural features of HS that are responsiBle for the specific Binding of CyPB. In addition to the involvement of 2-O,6-O, and N-sulfate groups, we also demonstrated that Binding of CyPB was dependent on the presence of N-unsuBstituted glucosamine residues (GlcNH2), which have Been reported to Be precursors for sulfation By 3-O-sulfotransferases-3 (3-OST-3). Interestingly, 3-OST-3B isoform was found to Be the main 3-OST isoenzyme expressed in peripheral Blood T lymphocytes and Jurkat T cells. Moreover, down-regulation of the expression of 3-OST-3 By RNA interference potently reduced CyPB Binding and consequent activation of p44/42 mitogen-activated protein kinases. Altogether, our results strongly support the hypothesis that 3-O-sulfation of GlcNH2 residues could Be a key modification that provides specialized HS structures for CyPB Binding to responsive cells. Given that 3-O-sulfation of GlcNH2-containing HS By 3-OST-3 also provides Binding sites for glycoprotein gD of herpes simplex virus type I, these findings suggest an intriguing structural linkage Between the HS sequences involved in CyPB Binding and viral infection.
Hanqing Guo - One of the best experts on this subject based on the ideXlab platform.
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gastric cancer cell proliferation and survival is enaBled By a <B>CyclophilinB> B stat3 mir 520d 5p signaling feedBack loop
Cancer Research, 2017Co-Authors: Hanqing Guo, Xiaodi Zhao, Jiang Jin, Lifeng Zhang, Yongzhan Nie, Yongquan Shi, Daiming FanAbstract:Molecular links Between inflammation and cancer remain oBscure despite their great pathogenic significance. The JAK2/STAT3 pathway activated By IL6 and other proinflammatory cytokines has garnered attention as a pivotal link in cancer pathogenesis, But the Basis for its activation in cancer cells is not understood. Here we report that an IL6-triggered feedBack loop involving STAT3-mediated suppression of miR-520d-5p and upregulation of its downstream target <B>CyclophilinB> B (CypB) regulate the growth and survival of gastric cancer cells. In clinical specimens of gastric cancer, we documented increased expression of CypB and activation of STAT3. Mechanistic investigations identified miR-520d-5p as a regulator of CypB mRNA levels. This signaling axis regulated gastric cancer growth By modulating phosphorylation of STAT3. Furthermore, miR-520d-5p was identified as a direct STAT3 target and IL6-mediated inhiBition of miR-520d-5p relied upon STAT3 activity. Our findings define a positive feedBack loop that drives gastric carcinogenesis as influenced By H. pylori infections that involve proinflammatory IL6 stimulation. Cancer Res; 77(5); 1227-40. ©2016 AACR.
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Gastric Cancer Cell Proliferation and Survival Is EnaBled By a <B>CyclophilinB> B/STAT3/miR-520d-5p Signaling FeedBack Loop.
Cancer research, 2016Co-Authors: Hanqing Guo, Xiaodi Zhao, Jiang Jin, Lifeng Zhang, Yongzhan Nie, Yongquan ShiAbstract:Molecular links Between inflammation and cancer remain oBscure despite their great pathogenic significance. The JAK2/STAT3 pathway activated By IL6 and other proinflammatory cytokines has garnered attention as a pivotal link in cancer pathogenesis, But the Basis for its activation in cancer cells is not understood. Here we report that an IL6-triggered feedBack loop involving STAT3-mediated suppression of miR-520d-5p and upregulation of its downstream target <B>CyclophilinB> B (CypB) regulate the growth and survival of gastric cancer cells. In clinical specimens of gastric cancer, we documented increased expression of CypB and activation of STAT3. Mechanistic investigations identified miR-520d-5p as a regulator of CypB mRNA levels. This signaling axis regulated gastric cancer growth By modulating phosphorylation of STAT3. Furthermore, miR-520d-5p was identified as a direct STAT3 target and IL6-mediated inhiBition of miR-520d-5p relied upon STAT3 activity. Our findings define a positive feedBack loop that drives gastric carcinogenesis as influenced By H. pylori infections that involve proinflammatory IL6 stimulation. Cancer Res; 77(5); 1227-40. ©2016 AACR.
Geneviève Spik - One of the best experts on this subject based on the ideXlab platform.
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HEMOSTASIS, THROMBOSIS, AND VASCULAR BIOLOGY <B>CyclophilinB> B Binding to Platelets Supports Calcium-Dependent Adhesion to Collagen
2016Co-Authors: Fabrice Allain, Mathieu Carpentier, Sandrine Durieux, Geneviève SpikAbstract:We have recently reported that <B>CyclophilinB> B (CyPB), a secreted cyclosporine-Binding protein, could Bind to T lymphocytes through interactions with two types of Binding sites. The first ones, referred to as type I, involve interactions with the conserved domain of CyPB and promote the endocytosis of surface-Bound ligand, while the second type of Binding sites, termed type II, are represented By glycosaminoglycans (GAG). Here, we further investigated the interactions of CyPB with Blood cell populations. In addition to lymphocytes, CyPB was found to interact mainly with platelets. The Binding is specific, with a dissociation constant (kd) of 9 6 3 nmol/L and the numBer of sites estimated at 960 6 60 per cell. Platelet glycosaminoglycans are not required for the interactions, But the Binding is dramatically reduced By active cyclosporine derivatives. We then analyzed the Biologic effects of CyPB and found a significant increase in platelet adhesion to collagen. Concurrently, CyPB initiates a transmemBranous influx of Ca21 and induces the phosphorylation of the P-20 light chains of myosin. Taken together, the present results demonstrate for the first time that extracellular CyPB specifically interacts with platelets through a functional receptor related to the lymphocyte type I Binding sites and might act By regulating the activity of a receptor-operated memBrane Ca21 channel.
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High Binding capacity of <B>CyclophilinB> B to chondrocyte heparan sulfate proteoglycans and its release from the cell surface By matrix metalloproteinases possiBle role as a proinflammatory mediator in arthritis
Arthritis and rheumatism, 2003Co-Authors: Frédéric De Ceuninck, Fabrice Allain, Geneviève Spik, Audrey Caliez, Paul Michel VanhoutteAbstract:OBjective To study <B>CyclophilinB> B, a protein newly identified as a secretion product of cultured chondrocytes, in the context of chondrocyte pathoBiology. Methods <B>CyclophilinB> B was purified By sequential chromatographic processing of the secretion medium of cultured guinea pig chondrocytes. Its presence Both at the surface of chondrocyte monolayers and in cartilage was demonstrated By immunohistochemistry. Binding sites at the surface of chondrocytes were characterized By Scatchard plot analysis using 125I-laBeled <B>CyclophilinB> B, and By glycosidase treatments. The release of <B>CyclophilinB> B from chondrocytes By activated matrix metalloproteinases (MMPs) was studied By Western Blot analysis. Results <B>CyclophilinB> B was present at the surface of cultured chondrocytes and within cartilage, Both in cells and in the extracellular matrix, with a particularly intense staining in the superficial layer. It was secreted constitutively By chondrocytes and cartilage explants. Its secretion was enhanced after treatment with its pharmacologic Binding partner, cyclosporin A (CSA). Experiments with 125I-laBeled <B>CyclophilinB> B demonstrated the presence of high-capacity, low-affinity, NaCl-sensitive Binding sites at the surface of chondrocytes. Cell-Bound <B>CyclophilinB> B could Be released By heparinase treatment, demonstrating Binding to pericellular heparan sulfate proteoglycans (HSPGs). Chondroitinase or keratanase treatments had no effect. MMPs 1, 2, 3, 9, and 13 released intact <B>CyclophilinB> B from the cell surface, proBaBly By cleavage of HSPGs. This effect was reversed By the Broad-spectrum MMP inhiBitor, marimastat. Conclusion <B>CyclophilinB> B is a secreted CSA-Binding protein involved in inflammatory events. It can induce chemotaxis in human neutrophils and T lymphocytes. The finding that <B>CyclophilinB> B is an intrinsic component of cartilage and that it can Be released By MMPs suggests that it has a role in the pathogenesis of arthritic diseases, even more so since its signaling receptor is present within the inflamed joint Both on T cells and in the rheumatoid synovium.
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Receptor-Mediated Transcytosis of <B>CyclophilinB> B Through the Blood—Brain Barrier
Journal of neurochemistry, 2002Co-Authors: Mathieu Carpentier, Agnès Denys, Fabrice Allain, Sandrine Durieux, Laurence Descamps, Laurence Fenart, Claudine Kieda, Roméo Cecchelli, Geneviève SpikAbstract:<B>CyclophilinB> B (CyPB) is a cyclosporin A (CsA)- Binding protein mainly located in intracellular vesicles and secreted in Biological fluids. In previous works, we demonstrated that CyPB interacts with T lymphocytes and enhances in vitro cellular incorporation and activity of CsA. In addition to its immunosuppressive activity, CsA is aBle to promote regeneration of damaged peripheral nerves. However, the crossing of the drug from plasma to neural tissue is restricted By the relative impermeaBility of the Blood–Brain Barrier. To know whether CyPB might also participate in the delivery of CsA into the Brain, we have analyzed the interactions of CyPB with Brain capillary endothelial cells. First, we demonstrated that CyPB Binds to two types of Binding sites present at the surface of capillary endothelial cells from various species of tissues. The first type of Binding sites (KD = 300 nM; numBer of sites = 3 x 106) is related to interactions with negatively charged compounds such as proteoglycans. The second type of Binding sites, ~50,000 per cell, exhiBits a higher affinity for CyPB (KD = 15 nM) and is involved in an endocytosis process, indicating it might correspond to a functional receptor. Finally, the use of an in vitro model of Blood–Brain Barrier allowed us to demonstrate that CyPB is transcytosed By a receptor-mediated pathway (flux = 16.5 fmol/cm²/h). In these conditions, CyPB did not significantly modify the passage of CsA, indicating that it is unlikely to provide a pathway for CsA Brain delivery.
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<B>CyclophilinB> B Binding to platelets supports calcium-dependent adhesion to collagen.
Blood, 1999Co-Authors: Fabrice Allain, Agnès Denys, Mathieu Carpentier, Sandrine Durieux, Geneviève SpikAbstract:We have recently reported that <B>CyclophilinB> B (CyPB), a secreted cyclosporine-Binding protein, could Bind to T lymphocytes through interactions with two types of Binding sites. The first ones, referred to as type I, involve interactions with the conserved domain of CyPB and promote the endocytosis of surface-Bound ligand, while the second type of Binding sites, termed type II, are represented By glycosaminoglycans (GAG). Here, we further investigated the interactions of CyPB with Blood cell populations. In addition to lymphocytes, CyPB was found to interact mainly with platelets. The Binding is specific, with a dissociation constant (kd) of 9 ± 3 nmol/L and the numBer of sites estimated at 960 ± 60 per cell. Platelet glycosaminoglycans are not required for the interactions, But the Binding is dramatically reduced By active cyclosporine derivatives. We then analyzed the Biologic effects of CyPB and found a significant increase in platelet adhesion to collagen. Concurrently, CyPB initiates a transmemBranous influx of Ca2+ and induces the phosphorylation of the P-20 light chains of myosin. Taken together, the present results demonstrate for the first time that extracellular CyPB specifically interacts with platelets through a functional receptor related to the lymphocyte type I Binding sites and might act By regulating the activity of a receptor-operated memBrane Ca2+ channel.
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Two Distinct Regions of <B>CyclophilinB> B Are Involved in the Recognition of a Functional Receptor and of Glycosaminoglycans on T Lymphocytes
The Journal of biological chemistry, 1999Co-Authors: Mathieu Carpentier, Agnès Denys, Fabrice Allain, Bernard Haendler, Christophe Mariller, Monique Benaïssa, Geneviève SpikAbstract:ABstract <B>CyclophilinB> B is a cyclosporin A-Binding protein exhiBiting peptidyl-prolyl cis/trans isomerase activity. We have previously shown that it interacts with two types of Binding sites on T lymphocytes. The type I sites correspond to specific functional receptors and the type II sites to sulfated glycosaminoglycans. The interactions of <B>CyclophilinB> B with type I and type II sites are reduced in the presence of cyclosporin A and of a synthetic peptide mimicking the N-terminal part of <B>CyclophilinB> B, respectively, suggesting that the protein possesses two distinct Binding regions. In this study, we intended to characterize the areas of <B>CyclophilinB> B involved in the interactions with Binding sites present on Jurkat cells. The use of <B>CyclophilinB> B mutants modified in the N-terminal region demonstrated that the 3Lys-Lys-Lys5 and14Tyr-Phe-Asp16 clusters are proBaBly solely required for the interactions with the type II sites. We further engineered mutants of the conserved central core of <B>CyclophilinB> B, which Bears the catalytic and the cyclosporin A Binding sites as an approach to localize the Binding regions for the type I sites. The enzymatic activity of <B>CyclophilinB> B was dramatically reduced after suBstitution of the Arg62 and Phe67residues, whereas the cyclosporin A Binding activity was destroyed By mutation of the Trp128 residue and strongly decreased after modification of the Phe67 residue. Only the suBstitution of the Trp128 residue reduced the Binding of the resulting <B>CyclophilinB> B mutant to type I Binding sites. The catalytic site of <B>CyclophilinB> B therefore did not seem to Be essential for cellular Binding and the cyclosporin A Binding site appeared to Be partially involved in the Binding to type I sites.
