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Michael Scharl - One of the best experts on this subject based on the ideXlab platform.
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autoimmune susceptibility gene ptpn2 is required for clearance of adherent invasive escherichia coli by integrating bacterial uptake and lysosomal defence
Gut, 2021Co-Authors: Marianne R. Spalinger, Michael Scharl, Michel L Tremblay, Ali Shawki, Pritha Chatterjee, Vinicius Canale, Alina N Santos, Anica Sayocbecerra, James Borneman, Declan F MccoleAbstract:Objectives Alterations in the intestinal microbiota are linked with a wide range of autoimmune and inflammatory conditions, including inflammatory bowel diseases (IBD), where pathobionts penetrate the intestinal barrier and promote inflammatory reactions. In patients with IBD, the ability of intestinal macrophages to efficiently clear invading pathogens is compromised resulting in increased bacterial translocation and excessive immune reactions. Here, we investigated how an IBD-associated loss-of-function variant in the protein tyrosine phosphatase non-receptor type 2 (PTPN2) gene, or loss of PTPN2 expression affected the ability of macrophages to respond to invading bacteria. Design IBD patient-derived macrophages with wild-type (WT) PTPN2 or carrying the IBD-associated PTPN2 SNP, peritoneal macrophages from WT and constitutive PTPN2-knockout mice, as well as mice specifically lacking PTPN2 in macrophages were infected with non-invasive K12 Escherichia coli, the human adherent-invasive E. coli (AIEC) LF82, or a novel mouse AIEC (mAIEC) strain. Results Loss of PTPN2 severely compromises the ability of macrophages to clear invading bacteria. Specifically, loss of functional PTPN2 promoted pathobiont invasion/uptake into macrophages and intracellular survival/proliferation by three distinct mechanisms: Increased bacterial uptake was mediated by enhanced expression of carcinoembryonic antigen cellular adhesion molecule (CEACAM)1 and CEACAM6 in PTPN2-deficient cells, while reduced bacterial clearance resulted from defects in autophagy coupled with compromised lysosomal acidification. In vivo, mice lacking PTPN2 in macrophages were more susceptible to mAIEC infection and mAIEC-induced disease. Conclusions Our findings reveal a tripartite regulatory mechanism by which PTPN2 preserves macrophage antibacterial function, thus crucially contributing to host defence against invading bacteria.
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PTPN2 Regulates Interactions Between Macrophages and Intestinal Epithelial Cells to Promote Intestinal Barrier Function.
Gastroenterology, 2020Co-Authors: Marianne R. Spalinger, Ali Shawki, Vinicius Canale, Alina N Santos, Anica Sayoc-becerra, Moorthy Krishnan, Anna Niechcial, Nicole Obialo, Michael ScharlAbstract:Abstract Background & Aims The mechanisms by which macrophages regulate intestinal epithelial cell (IEC) barrier properties are poorly understood. Protein tyrosine phosphatase non-receptor type 2 (PTPN2) protects the IEC barrier from inflammation-induced disruption and regulates macrophage functions. We investigated whether PTPN2 controls interactions between IECs and macrophages to maintain intestinal barrier function. Methods Human IEC (Caco-2BBe/HT-29.cl19a cells) and mouse enteroid monolayers were co-cultured with human macrophages (THP-1, U937, primary monocyte-derived macrophages from patients with inflammatory bowel disease [IBD]) or mouse macrophages, respectively. We assessed barrier function (transepithelial electrical resistance [TEER] and permeability to 4 kDa fluorescently labeled dextran [FD4] or rhodamine B-dextran 70 kDa) and macrophage polarization. We analyzed intestinal tissues from mice with myeloid cell-specific deletion of PTPN2 (Ptpn2-LysMCre mice) and mice without disruption of Ptpn2 (controls); some mice were given injections of a neutralizing antibody against interleukin 6 (IL6). Proteins were knocked down in macrophages and/or IECs with small hairpin RNAs. Results Knockdown of PTPN2 in either macrophages and/or IECs increased the permeability of IEC monolayers, had a synergistic effect when knocked down from both cell types, and increased development of inflammatory macrophages in macrophage–IEC co-cultures. Colon lamina propria from Ptpn2-LysMCre mice had significant increases in inflammatory macrophages; these mice had increased in vivo and ex vivo colon permeability to FD4 and reduced ex vivo colon TEER. Nanostring analysis revealed significant increases in expression of IL6 in colon macrophages from Ptpn2-LysMCre mice. An IL6 blocking antibody reversed the effects of PTPN2-deficient macrophages, reducing permeability of IEC monolayers in culture and in Ptpn2-LysMCre mice. Macrophages from patients with IBD carrying a single-nucleotide polymorphism associated with the disease (PTPN2 rs1893217) had the same features of PTPN2-deficient macrophages from mice, including reduced TEER and increased permeability in co-cultures with human IEC or mouse enteroid monolayers, which were restored by anti-IL6. Conclusions PTPN2 is required for interactions between macrophages and IECs; loss of PTPN2 from either cell type results in intestinal barrier defects, and loss from both cell types has a synergistic effect. We provide a mechanism by which PTPN2 gene variants compromise intestinal epithelial barrier function and increase risk of inflammatory disorders such as IBD.
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presence of ptpn2 snp rs1893217 enhances the anti inflammatory effect of spermidine
Inflammatory Bowel Diseases, 2020Co-Authors: Anna Niechcial, Declan F Mccole, Nicole Obialo, Claudia Gottier, Silvia Lang, Matthias Butter, Salomon M Manz, K Babler, Lisa Van Der Lely, Michael ScharlAbstract:Background The single nucleotide polymorphism (SNP) rs1893217 within the gene locus encoding PTPN2 represents a risk factor for inflammatory bowel disease (IBD). Our previous work demonstrated reduced PTPN2 activity and subsequently increased inflammatory signaling upon presence of SNP rs1893217. The naturally occurring polyamine spermidine reduces pro-inflammatory signaling via induction of PTPN2 activity; however, the effect of SNP rs1893217 on the anti-inflammatory potential of spermidine is still unknown. Here, we investigated how presence of SNP rs1893217 affects treatment efficacy of spermidine and whether it might serve as a potential biomarker for spermidine treatment. Methods Human T84 (wild-type [WT] for PTPN2 SNP rs1893217) and HT29 (heterozygous for PTPN2 SNP rs1893217) intestinal epithelial cells (IECs) were treated with several polyamines from the putrescine-spermidine pathway. T84 and HT29 IECs, THP-1 monocytes (WT and transfected with a lentiviral vector expressing PTPN2 SNP rs1893217) and genotyped, patient-derived peripheral blood mononuclear cells were challenged with IFN-γ and/or spermidine. Results Among the analyzed polyamines, spermidine was the most efficient activator of PTPN2 phosphatase activity, regardless of the PTPN2 genotype. Spermidine suppressed IFN-γ-induced STAT1 and STAT3 phosphorylation, along with decreased mRNA expression of ICAM-1, NOD2, and IFNG in IECs and monocytes. Of note, these effects were clearly more pronounced when the disease-associated PTPN2 C-variant in SNP rs1893217 was present. Conclusions Our data demonstrate that spermidine is the most potent polyamine in the putrescine-spermine axis for inducing PTPN2 enzymatic activity. The anti-inflammatory effect of spermidine is potentiated in the presence of SNP rs1893217, and this SNP might thus be a useful biomarker for possible spermidine-treatment in IBD patients.
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The presence of genetic risk variants within PTPN2 and PTPN22 is associated with intestinal microbiota alterations in Swiss IBD cohort patients.
PloS one, 2018Co-Authors: Bahtiyar Yilmaz, Marianne R. Spalinger, Luc Biedermann, Yannick Franc, Nicolas Fournier, Jean-benoit Rossel, Pascal Juillerat, Gerhard Rogler, Andrew J. Macpherson, Michael ScharlAbstract:Background Genetic risk factors, intestinal microbiota and a dysregulated immune system contribute to the pathogenesis of inflammatory bowel disease (IBD). We have previously demonstrated that dysfunction of protein tyrosine phosphatase non-receptor type 2 (PTPN2) and PTPN22 contributes to alterations of intestinal microbiota and the onset of chronic intestinal inflammation in vivo. Here, we investigated the influence of PTPN2 and PTPN22 gene variants on intestinal microbiota composition in IBD patients. Methods Bacterial DNA from mucosa-associated samples of 75 CD and 57 UC patients were sequenced using 16S rRNA sequencing approach. Microbial analysis, including alpha diversity, beta diversity and taxonomical analysis by comparing to PTPN2 (rs1893217) and PTPN22 (rs2476601) genotypes was performed in QIIME, the phyloseq R package and MaAsLin pipeline. Results In PTPN2 variant UC patients, we detected an increase in relative abundance of unassigned genera from Clostridiales and Lachnospiraceae families and reduction of Roseburia when compared to PTPN2 wild-type (WT) patients. Ruminoccocus was increased in PTPN22 variant UC patients. In CD patients with severe disease course, Faecalibacterium, Bilophila, Coprococcus, unclassified Erysipelotrichaeceae, unassigned genera from Clostridiales and Ruminococcaceae families were reduced and Bacteroides were increased in PTPN2 WT carriers, while Faecalibacterium, Bilophila, Coprococcus, and Erysipelotrichaeceae were reduced in PTPN22 WT patients when compared to patients with mild disease. In UC patients with severe disease, relative abundance of Lachnobacterium was reduced in PTPN2 and PTPN22 WT patients, Dorea was increased in samples from PTPN22 WT carriers and an unassigned genus from Ruminococcaceae gen. was increased in patients with PTPN2 variant genotype. Conclusions We identified that IBD-associated genetic risk variants, disease severity and the interaction of these factors are related to significant alterations in intestinal microbiota composition of IBD patients.
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ab0114 comparative analysis of the expression of protein tyrosine phosphatase non receptor type 2 ptpn2 in autoimmune disease
Annals of the Rheumatic Diseases, 2014Co-Authors: Michael Scharl, Borbala Aradi, Maria Armaka, Maria Filkova, Masaru Kato, Katja Klein, B A Michel, L Senolt, Edit I BuzasAbstract:Background Protein Tyrosine Phosphatase Non-receptor Type 2 (PTPN2) is a phosphatase that plays an important role in inhibiting T-cell activation. The PTPN2 gene contains SNPs that are risk factors for the development of rheumatoid arthritis (RA), Crohn9s disease and type 1 diabetes. We have previously shown that PTPN2 expression is elevated in RA synovial fibroblasts (RASF) compared to osteoarthritis synovial fibroblasts (OASF). Objectives PTPN2 expression in peripheral blood mononuclear cells (PBMC) from patients with RA, OA, ankylosing spondylitis (AS) and systemic lupus erythematosus (SLE) was analyzed and compared to those from healthy subjects. Furthermore, we aim to analyze the inflammation-induced expression of PTPN2 in synovial fibroblasts from patients with RA and compare it with the expression in the TNF transgenic mouse model. Methods PBMC were isolated using Ficoll-Paque (healthy controls n=5, OA n=1, RA n=5, AS n=6, SLE n=7)and either lysed directly or cultured and stimulated with tumor necrosis factor α (TNFα, 10 ng/ml, 24 h). Synovial fibroblasts were obtained from RA patients undergoing surgery and from the TNF transgenic mouse model. SF were stimulated with TNFα (10 ng/ml, 24 h or 1 week). Levels of PTPN2 mRNA were measured using TaqMan Real-time PCR. Western blot was used to measure PTPN2 protein levels. Results PTPN2 is expressed in PBMC, however, no significant changes were found in the expression of PTPN2 in PBMC from autoimmune diseases (dCt ± SD, healthy controls 3.98±0.97, OA 4.00±0.0, RA 4.28±0.39, AS 4.06±0.54, SLE 4.05±0.48) In PBMC from healthy controls, stimulation with TNFα (10 ng/ml, 24h) did not increase the levels of PTPN2 (n=4, dCt ± SD unstimulated 4.18±0.3, TNF 4.23±0.8). Basal levels of PTPN2 were higher in RASF compared to OASF (mRNA: 1.6 fold, p Conclusions In the current study we show that PTPN2 expression is elevated in RASF but it is not changed in PBMC. Since we have previously shown that PTPN2 negatively regulates inflammation in RASF, we conclude that PTPN2 is a local regulator in the affected inflamed joints but not a modulator of systemic inflammation. Acknowledgements IMI BTCure, IAR, EURO-TEAM Disclosure of Interest None declared DOI 10.1136/annrheumdis-2014-eular.4212
Marianne R. Spalinger - One of the best experts on this subject based on the ideXlab platform.
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autoimmune susceptibility gene ptpn2 is required for clearance of adherent invasive escherichia coli by integrating bacterial uptake and lysosomal defence
Gut, 2021Co-Authors: Marianne R. Spalinger, Michael Scharl, Michel L Tremblay, Ali Shawki, Pritha Chatterjee, Vinicius Canale, Alina N Santos, Anica Sayocbecerra, James Borneman, Declan F MccoleAbstract:Objectives Alterations in the intestinal microbiota are linked with a wide range of autoimmune and inflammatory conditions, including inflammatory bowel diseases (IBD), where pathobionts penetrate the intestinal barrier and promote inflammatory reactions. In patients with IBD, the ability of intestinal macrophages to efficiently clear invading pathogens is compromised resulting in increased bacterial translocation and excessive immune reactions. Here, we investigated how an IBD-associated loss-of-function variant in the protein tyrosine phosphatase non-receptor type 2 (PTPN2) gene, or loss of PTPN2 expression affected the ability of macrophages to respond to invading bacteria. Design IBD patient-derived macrophages with wild-type (WT) PTPN2 or carrying the IBD-associated PTPN2 SNP, peritoneal macrophages from WT and constitutive PTPN2-knockout mice, as well as mice specifically lacking PTPN2 in macrophages were infected with non-invasive K12 Escherichia coli, the human adherent-invasive E. coli (AIEC) LF82, or a novel mouse AIEC (mAIEC) strain. Results Loss of PTPN2 severely compromises the ability of macrophages to clear invading bacteria. Specifically, loss of functional PTPN2 promoted pathobiont invasion/uptake into macrophages and intracellular survival/proliferation by three distinct mechanisms: Increased bacterial uptake was mediated by enhanced expression of carcinoembryonic antigen cellular adhesion molecule (CEACAM)1 and CEACAM6 in PTPN2-deficient cells, while reduced bacterial clearance resulted from defects in autophagy coupled with compromised lysosomal acidification. In vivo, mice lacking PTPN2 in macrophages were more susceptible to mAIEC infection and mAIEC-induced disease. Conclusions Our findings reveal a tripartite regulatory mechanism by which PTPN2 preserves macrophage antibacterial function, thus crucially contributing to host defence against invading bacteria.
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PTPN2 Regulates Interactions Between Macrophages and Intestinal Epithelial Cells to Promote Intestinal Barrier Function.
Gastroenterology, 2020Co-Authors: Marianne R. Spalinger, Ali Shawki, Vinicius Canale, Alina N Santos, Anica Sayoc-becerra, Moorthy Krishnan, Anna Niechcial, Nicole Obialo, Michael ScharlAbstract:Abstract Background & Aims The mechanisms by which macrophages regulate intestinal epithelial cell (IEC) barrier properties are poorly understood. Protein tyrosine phosphatase non-receptor type 2 (PTPN2) protects the IEC barrier from inflammation-induced disruption and regulates macrophage functions. We investigated whether PTPN2 controls interactions between IECs and macrophages to maintain intestinal barrier function. Methods Human IEC (Caco-2BBe/HT-29.cl19a cells) and mouse enteroid monolayers were co-cultured with human macrophages (THP-1, U937, primary monocyte-derived macrophages from patients with inflammatory bowel disease [IBD]) or mouse macrophages, respectively. We assessed barrier function (transepithelial electrical resistance [TEER] and permeability to 4 kDa fluorescently labeled dextran [FD4] or rhodamine B-dextran 70 kDa) and macrophage polarization. We analyzed intestinal tissues from mice with myeloid cell-specific deletion of PTPN2 (Ptpn2-LysMCre mice) and mice without disruption of Ptpn2 (controls); some mice were given injections of a neutralizing antibody against interleukin 6 (IL6). Proteins were knocked down in macrophages and/or IECs with small hairpin RNAs. Results Knockdown of PTPN2 in either macrophages and/or IECs increased the permeability of IEC monolayers, had a synergistic effect when knocked down from both cell types, and increased development of inflammatory macrophages in macrophage–IEC co-cultures. Colon lamina propria from Ptpn2-LysMCre mice had significant increases in inflammatory macrophages; these mice had increased in vivo and ex vivo colon permeability to FD4 and reduced ex vivo colon TEER. Nanostring analysis revealed significant increases in expression of IL6 in colon macrophages from Ptpn2-LysMCre mice. An IL6 blocking antibody reversed the effects of PTPN2-deficient macrophages, reducing permeability of IEC monolayers in culture and in Ptpn2-LysMCre mice. Macrophages from patients with IBD carrying a single-nucleotide polymorphism associated with the disease (PTPN2 rs1893217) had the same features of PTPN2-deficient macrophages from mice, including reduced TEER and increased permeability in co-cultures with human IEC or mouse enteroid monolayers, which were restored by anti-IL6. Conclusions PTPN2 is required for interactions between macrophages and IECs; loss of PTPN2 from either cell type results in intestinal barrier defects, and loss from both cell types has a synergistic effect. We provide a mechanism by which PTPN2 gene variants compromise intestinal epithelial barrier function and increase risk of inflammatory disorders such as IBD.
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The presence of genetic risk variants within PTPN2 and PTPN22 is associated with intestinal microbiota alterations in Swiss IBD cohort patients.
PloS one, 2018Co-Authors: Bahtiyar Yilmaz, Marianne R. Spalinger, Luc Biedermann, Yannick Franc, Nicolas Fournier, Jean-benoit Rossel, Pascal Juillerat, Gerhard Rogler, Andrew J. Macpherson, Michael ScharlAbstract:Background Genetic risk factors, intestinal microbiota and a dysregulated immune system contribute to the pathogenesis of inflammatory bowel disease (IBD). We have previously demonstrated that dysfunction of protein tyrosine phosphatase non-receptor type 2 (PTPN2) and PTPN22 contributes to alterations of intestinal microbiota and the onset of chronic intestinal inflammation in vivo. Here, we investigated the influence of PTPN2 and PTPN22 gene variants on intestinal microbiota composition in IBD patients. Methods Bacterial DNA from mucosa-associated samples of 75 CD and 57 UC patients were sequenced using 16S rRNA sequencing approach. Microbial analysis, including alpha diversity, beta diversity and taxonomical analysis by comparing to PTPN2 (rs1893217) and PTPN22 (rs2476601) genotypes was performed in QIIME, the phyloseq R package and MaAsLin pipeline. Results In PTPN2 variant UC patients, we detected an increase in relative abundance of unassigned genera from Clostridiales and Lachnospiraceae families and reduction of Roseburia when compared to PTPN2 wild-type (WT) patients. Ruminoccocus was increased in PTPN22 variant UC patients. In CD patients with severe disease course, Faecalibacterium, Bilophila, Coprococcus, unclassified Erysipelotrichaeceae, unassigned genera from Clostridiales and Ruminococcaceae families were reduced and Bacteroides were increased in PTPN2 WT carriers, while Faecalibacterium, Bilophila, Coprococcus, and Erysipelotrichaeceae were reduced in PTPN22 WT patients when compared to patients with mild disease. In UC patients with severe disease, relative abundance of Lachnobacterium was reduced in PTPN2 and PTPN22 WT patients, Dorea was increased in samples from PTPN22 WT carriers and an unassigned genus from Ruminococcaceae gen. was increased in patients with PTPN2 variant genotype. Conclusions We identified that IBD-associated genetic risk variants, disease severity and the interaction of these factors are related to significant alterations in intestinal microbiota composition of IBD patients.
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ptpn2 regulates inflammasome activation and controls onset of intestinal inflammation and colon cancer
Cell Reports, 2018Co-Authors: Marianne R. Spalinger, Roberto Manzini, Larissa Hering, Julianne B Riggs, Claudia Gottier, Silvia Lang, Kirstin Atrott, Antonia Fettelschoss, Florian Olomski, Thomas M KundigAbstract:Variants in the gene locus encoding protein tyrosine phosphatase non-receptor type 2 (PTPN2) are associated with inflammatory disorders, including inflammatory bowel diseases, rheumatoid arthritis, and type 1 diabetes. The anti-inflammatory role of PTPN2 is highlighted by the fact that PTPN2-deficient mice die a few weeks after birth because of systemic inflammation and severe colitis. However, the tissues, cells, and molecular mechanisms that contribute to this phenotype remain unclear. Here, we demonstrate that myeloid cell-specific deletion of PTPN2 in mice (PTPN2-LysMCre) promotes intestinal inflammation but protects from colitis-associated tumor formation in an IL-1β-dependent manner. Elevated levels of mature IL-1β production in PTPN2-LysMCre mice are a consequence of increased inflammasome assembly due to elevated phosphorylation of the inflammasome adaptor molecule ASC. Thus, we have identified a dual role for myeloid PTPN2 in directly regulating inflammasome activation and IL-1β production to suppress pro-inflammatory responses during colitis but promote intestinal tumor development.
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deficiency of protein tyrosine phosphatase non receptor type 2 in intestinal epithelial cells has no appreciable impact on dextran sulphate sodium colitis severity but promotes wound healing
Digestion, 2016Co-Authors: Stephanie Kasper, Marianne R. Spalinger, Claudia Gottier, Kirstin Atrott, Tina Raselli, Isabelle Freywagner, Irina Leonardi, Alexandra Gerstgrasser, Anne Fischbeckterhalle, Gerhard RoglerAbstract:Background/Aims: The protein tyrosine phosphatase non-receptor type 2 (PTPN2) is known to mediate susceptibility to inflammatory bowel diseases. Cell culture experiments suggest that PTPN2 influences barrier function, autophagy and secretion of pro-inflammatory cytokines. PTPN2 knockout mice die a few weeks after birth due to systemic inflammation, emphasizing the importance of this phosphatase in inflammatory processes. The aim of this study was to investigate the role of PTPN2 in colon epithelial cells by performing dextran sulphate sodium (DSS)-induced colitis in PTPN2xVilCre mice. Methods: Acute colitis was induced by administering 2.5 or 2% DSS for 7 days and chronic colitis by 4 cycles of treatment using 1% DSS. Body weight of mice was measured regularly and colonoscopy was done at the end of the experiments. Mice were sacrificed afterwards and colon specimens were obtained for H&E staining. For analysis of wound healing, mechanical wounds were introduced during endoscopy and wound closure assessed by daily colonoscopy. Results: Although colonoscopy and weight development suggested changes in colitis severity, the lack of any influence of PTPN2 deficiency on histological scoring for inflammation severity after acute or chronic DSS colitis indicates that colitis severity is not influenced by epithelial-specific loss of PTPN2. Chronic colitis induced the development of aberrant crypt foci more frequently in PTPN2xVilCre mice compared to their wild type littermates. On the other hand, loss of PTPN2-induced enhanced epithelial cell proliferation and promoted wound closure. Conclusions: Loss of PTPN2 in intestinal epithelial cells (IECs) has no significant influence on inflammation in DSS colitis. Obviously, loss of PTPN2 in IECs can be compensated in vivo, thereby suppressing a phenotype. This lack of a colitis-phenotype might be due to enhanced epithelial cell proliferation and subsequent increased wound-healing capacity of the epithelial layer.
Borbala Aradi - One of the best experts on this subject based on the ideXlab platform.
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ab0114 comparative analysis of the expression of protein tyrosine phosphatase non receptor type 2 ptpn2 in autoimmune disease
Annals of the Rheumatic Diseases, 2014Co-Authors: Michael Scharl, Borbala Aradi, Maria Armaka, Maria Filkova, Masaru Kato, Katja Klein, B A Michel, L Senolt, Edit I BuzasAbstract:Background Protein Tyrosine Phosphatase Non-receptor Type 2 (PTPN2) is a phosphatase that plays an important role in inhibiting T-cell activation. The PTPN2 gene contains SNPs that are risk factors for the development of rheumatoid arthritis (RA), Crohn9s disease and type 1 diabetes. We have previously shown that PTPN2 expression is elevated in RA synovial fibroblasts (RASF) compared to osteoarthritis synovial fibroblasts (OASF). Objectives PTPN2 expression in peripheral blood mononuclear cells (PBMC) from patients with RA, OA, ankylosing spondylitis (AS) and systemic lupus erythematosus (SLE) was analyzed and compared to those from healthy subjects. Furthermore, we aim to analyze the inflammation-induced expression of PTPN2 in synovial fibroblasts from patients with RA and compare it with the expression in the TNF transgenic mouse model. Methods PBMC were isolated using Ficoll-Paque (healthy controls n=5, OA n=1, RA n=5, AS n=6, SLE n=7)and either lysed directly or cultured and stimulated with tumor necrosis factor α (TNFα, 10 ng/ml, 24 h). Synovial fibroblasts were obtained from RA patients undergoing surgery and from the TNF transgenic mouse model. SF were stimulated with TNFα (10 ng/ml, 24 h or 1 week). Levels of PTPN2 mRNA were measured using TaqMan Real-time PCR. Western blot was used to measure PTPN2 protein levels. Results PTPN2 is expressed in PBMC, however, no significant changes were found in the expression of PTPN2 in PBMC from autoimmune diseases (dCt ± SD, healthy controls 3.98±0.97, OA 4.00±0.0, RA 4.28±0.39, AS 4.06±0.54, SLE 4.05±0.48) In PBMC from healthy controls, stimulation with TNFα (10 ng/ml, 24h) did not increase the levels of PTPN2 (n=4, dCt ± SD unstimulated 4.18±0.3, TNF 4.23±0.8). Basal levels of PTPN2 were higher in RASF compared to OASF (mRNA: 1.6 fold, p Conclusions In the current study we show that PTPN2 expression is elevated in RASF but it is not changed in PBMC. Since we have previously shown that PTPN2 negatively regulates inflammation in RASF, we conclude that PTPN2 is a local regulator in the affected inflamed joints but not a modulator of systemic inflammation. Acknowledgements IMI BTCure, IAR, EURO-TEAM Disclosure of Interest None declared DOI 10.1136/annrheumdis-2014-eular.4212
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thu0071 protein tyrosine phosphatase nonreceptor type 2 ptpn2 is an important regulator of inflammation and autophagy in rheumatoid arthritis
Annals of the Rheumatic Diseases, 2013Co-Authors: Borbala Aradi, Michael Scharl, Maria Filkova, Masaru Kato, Katja Klein, B A Michel, Edit I Buzas, Stephanie Kasper, M Bader, Astrid JungelAbstract:Background Recently we found that Protein Tyrosine Phosphatase Nonreceptor Type 2 (PTPN2) is involved in the apoptosis resistance of rheumatoid arthritis synovial fibroblasts (RASF). Objectives Autophagy is strongly connected to apoptosis, and is activated via a series of phosphorylation events. We wanted to investigate whether PTPN2 plays a role in autophagy and inflammation in RASF. Methods PTPN2 expression was analysed in synovial tissues by immunohistochemistry and real-time PCR. Transcription levels of PTPN2 were detected with or without tumor necrosis factor α (TNFα 10 ng/ml, 24 h), IL1β (1 ng/ml), LPS (100 µg/ml) and hypoxia (1%). PTPN2 protein levels were assessed by Western blotting. After silencing PTPN2 in RASF, commercially available ELISA was used to measure IL-6 and IL-8 in culture supernatants. TNF-related apoptosis-inducing ligand (TRAIL, 20 ng/ml, 24 h) induced apoptosis was measured after staining with AnnexinV using flow cytometry. Autophagy was induced by Thapsigargin (5 µM, 24h). Western blot was used to measure LC3B-I and LC3B-II. Results In the lining and the sublining layer of RA synovial tissue, a stronger PTPN2 staining was detected by immunohistochemistry compared to OA (n=7). That overexpression could also be confirmed on mRNA level (2.0 fold, RA tissue n=4, OA tissue n=5). Moreover, in RASF, the constitutive mRNA level of PTPN2 was higher than in OA synovial fibroblasts (OASF) (1.6 fold, p Conclusions Since levels of autophagy are lower in PTPN2 silenced RASF compared to scrambled control, it is indicated that increased PTPN2 protein expression in RASF induces inflammation and elevated autophagy in RASF. Acknowledgements This work was supported by IMI BTCure, IAR, Masterswitch-FP7 and ZIHP. Disclosure of Interest None Declared
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a9 13 tnf induced protein tyrosine phosphatase nonreceptor type 2 ptpn2 as a negative regulator of inflammation in rheumatoid arthritis
Annals of the Rheumatic Diseases, 2013Co-Authors: Borbala Aradi, Michael Scharl, Maria Filkova, Katja Klein, B A Michel, Edit I Buzas, Stephanie Kasper, Astrid JungelAbstract:Background and Objectives Protein Tyrosine Phosphatase Nonreceptor Type 2 (PTPN2) is a protein tyrosine phosphatase that plays a role in the development of autoimmune diseases. PTPN2 function has not been studied in rheumatoid arthritis (RA), although single nucleotide polymorphisms within the gene have been described to be associated with RA in genome wide association studies. Considering the involvement of PTPN2 in the regulation of key inflammatory pathways, our aim was to analyse the expression and function of PTPN2 in RA synovial fibroblasts (RASF). Materials and Methods The expression of PTPN2 was assessed in synovial tissue and fibroblasts (passage 4–10) from patients with RA and osteoarthritis (OA) using immunohistochemistry, real-time PCR (w/o tumour necrosis factor α (TNFα), IL1β, LPS and hypoxia) and Western blotting. PTPN2 was silenced with silencing RNA. Levels of IL-6 and IL-8 expression were measured by commercially available ELISA in cell culture supernatants after silencing PTPN2 in RASF w/o stimulation with tumour necrosis factor α (TNFα). Apoptosis of RASF was evaluated by AnnexinV staining using flow cytometry after stimulation with TNF-related apoptosis-inducing ligand (TRAIL, 20 ng/ml) for 24 hours. Results In RA synovial tissue, compared with OA, we observed a stronger staining of ptpn2 in both the lining and the sublining layer by immunohistochemistry. On mRNA level we confirmed this overexpression in RA synovial tissue (2.0 fold, n = 4–5). In isolated RASF the constitutive mRNA level of PTPN2 was higher than in OASF (1.6 fold, p Levels of PTPN2 were further upregulated in RASF after stimulation with inflammatory cytokines such as TNFα (10 ng/ml, 24 hours, 3.1 fold, p Conclusions Our findings indicate that PTPN2, known to be involved in the pathogenesis of several autoimmune diseases, could be an important negative regulator of inflammation in RASF. Acknowledgement This work was supported by IMI BTCure, IAR and Masterswitch-FP7.
Stephanie Kasper - One of the best experts on this subject based on the ideXlab platform.
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deficiency of protein tyrosine phosphatase non receptor type 2 in intestinal epithelial cells has no appreciable impact on dextran sulphate sodium colitis severity but promotes wound healing
Digestion, 2016Co-Authors: Stephanie Kasper, Marianne R. Spalinger, Claudia Gottier, Kirstin Atrott, Tina Raselli, Isabelle Freywagner, Irina Leonardi, Alexandra Gerstgrasser, Anne Fischbeckterhalle, Gerhard RoglerAbstract:Background/Aims: The protein tyrosine phosphatase non-receptor type 2 (PTPN2) is known to mediate susceptibility to inflammatory bowel diseases. Cell culture experiments suggest that PTPN2 influences barrier function, autophagy and secretion of pro-inflammatory cytokines. PTPN2 knockout mice die a few weeks after birth due to systemic inflammation, emphasizing the importance of this phosphatase in inflammatory processes. The aim of this study was to investigate the role of PTPN2 in colon epithelial cells by performing dextran sulphate sodium (DSS)-induced colitis in PTPN2xVilCre mice. Methods: Acute colitis was induced by administering 2.5 or 2% DSS for 7 days and chronic colitis by 4 cycles of treatment using 1% DSS. Body weight of mice was measured regularly and colonoscopy was done at the end of the experiments. Mice were sacrificed afterwards and colon specimens were obtained for H&E staining. For analysis of wound healing, mechanical wounds were introduced during endoscopy and wound closure assessed by daily colonoscopy. Results: Although colonoscopy and weight development suggested changes in colitis severity, the lack of any influence of PTPN2 deficiency on histological scoring for inflammation severity after acute or chronic DSS colitis indicates that colitis severity is not influenced by epithelial-specific loss of PTPN2. Chronic colitis induced the development of aberrant crypt foci more frequently in PTPN2xVilCre mice compared to their wild type littermates. On the other hand, loss of PTPN2-induced enhanced epithelial cell proliferation and promoted wound closure. Conclusions: Loss of PTPN2 in intestinal epithelial cells (IECs) has no significant influence on inflammation in DSS colitis. Obviously, loss of PTPN2 in IECs can be compensated in vivo, thereby suppressing a phenotype. This lack of a colitis-phenotype might be due to enhanced epithelial cell proliferation and subsequent increased wound-healing capacity of the epithelial layer.
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ptpn2 controls differentiation of cd4 t cells and limits intestinal inflammation and intestinal dysbiosis
Mucosal Immunology, 2015Co-Authors: Marianne R. Spalinger, Stephan R Vavricka, Claudia Gottier, Silvia Lang, Kirstin Atrott, Stephanie Kasper, Christophe Chassard, Tina Raselli, Isabelle Freywagner, Florian MairAbstract:Loss-of-function variants within the gene locus encoding protein tyrosine phosphatase non-receptor type 2 (PTPN2) are associated with increased risk for Crohn's disease (CD). A disturbed regulation of T helper (Th) cell responses causing loss of tolerance against self- or commensal-derived antigens and an altered intestinal microbiota plays a pivotal role in CD pathogenesis. Loss of PTPN2 in the T-cell compartment causes enhanced induction of Th1 and Th17 cells, but impaired induction of regulatory T cells (Tregs) in several mouse colitis models, namely acute and chronic dextran sodium sulfate colitis, and T-cell transfer colitis models. This results in increased susceptibility to intestinal inflammation and intestinal dysbiosis which is comparable with that observed in CD patients. We detected inflammatory infiltrates in liver, kidney, and skin and elevated autoantibody levels indicating systemic loss of tolerance in PTPN2-deficient animals. CD patients featuring a loss-of-function PTPN2 variant exhibit enhanced Th1 and Th17 cell, but reduced Treg markers when compared with PTPN2 wild-type patients in serum and intestinal tissue samples. Our data demonstrate that dysfunction of PTPN2 results in aberrant T-cell differentiation and intestinal dysbiosis similar to those observed in human CD. Our findings indicate a novel and crucial role for PTPN2 in chronic intestinal inflammation.
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thu0071 protein tyrosine phosphatase nonreceptor type 2 ptpn2 is an important regulator of inflammation and autophagy in rheumatoid arthritis
Annals of the Rheumatic Diseases, 2013Co-Authors: Borbala Aradi, Michael Scharl, Maria Filkova, Masaru Kato, Katja Klein, B A Michel, Edit I Buzas, Stephanie Kasper, M Bader, Astrid JungelAbstract:Background Recently we found that Protein Tyrosine Phosphatase Nonreceptor Type 2 (PTPN2) is involved in the apoptosis resistance of rheumatoid arthritis synovial fibroblasts (RASF). Objectives Autophagy is strongly connected to apoptosis, and is activated via a series of phosphorylation events. We wanted to investigate whether PTPN2 plays a role in autophagy and inflammation in RASF. Methods PTPN2 expression was analysed in synovial tissues by immunohistochemistry and real-time PCR. Transcription levels of PTPN2 were detected with or without tumor necrosis factor α (TNFα 10 ng/ml, 24 h), IL1β (1 ng/ml), LPS (100 µg/ml) and hypoxia (1%). PTPN2 protein levels were assessed by Western blotting. After silencing PTPN2 in RASF, commercially available ELISA was used to measure IL-6 and IL-8 in culture supernatants. TNF-related apoptosis-inducing ligand (TRAIL, 20 ng/ml, 24 h) induced apoptosis was measured after staining with AnnexinV using flow cytometry. Autophagy was induced by Thapsigargin (5 µM, 24h). Western blot was used to measure LC3B-I and LC3B-II. Results In the lining and the sublining layer of RA synovial tissue, a stronger PTPN2 staining was detected by immunohistochemistry compared to OA (n=7). That overexpression could also be confirmed on mRNA level (2.0 fold, RA tissue n=4, OA tissue n=5). Moreover, in RASF, the constitutive mRNA level of PTPN2 was higher than in OA synovial fibroblasts (OASF) (1.6 fold, p Conclusions Since levels of autophagy are lower in PTPN2 silenced RASF compared to scrambled control, it is indicated that increased PTPN2 protein expression in RASF induces inflammation and elevated autophagy in RASF. Acknowledgements This work was supported by IMI BTCure, IAR, Masterswitch-FP7 and ZIHP. Disclosure of Interest None Declared
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a9 13 tnf induced protein tyrosine phosphatase nonreceptor type 2 ptpn2 as a negative regulator of inflammation in rheumatoid arthritis
Annals of the Rheumatic Diseases, 2013Co-Authors: Borbala Aradi, Michael Scharl, Maria Filkova, Katja Klein, B A Michel, Edit I Buzas, Stephanie Kasper, Astrid JungelAbstract:Background and Objectives Protein Tyrosine Phosphatase Nonreceptor Type 2 (PTPN2) is a protein tyrosine phosphatase that plays a role in the development of autoimmune diseases. PTPN2 function has not been studied in rheumatoid arthritis (RA), although single nucleotide polymorphisms within the gene have been described to be associated with RA in genome wide association studies. Considering the involvement of PTPN2 in the regulation of key inflammatory pathways, our aim was to analyse the expression and function of PTPN2 in RA synovial fibroblasts (RASF). Materials and Methods The expression of PTPN2 was assessed in synovial tissue and fibroblasts (passage 4–10) from patients with RA and osteoarthritis (OA) using immunohistochemistry, real-time PCR (w/o tumour necrosis factor α (TNFα), IL1β, LPS and hypoxia) and Western blotting. PTPN2 was silenced with silencing RNA. Levels of IL-6 and IL-8 expression were measured by commercially available ELISA in cell culture supernatants after silencing PTPN2 in RASF w/o stimulation with tumour necrosis factor α (TNFα). Apoptosis of RASF was evaluated by AnnexinV staining using flow cytometry after stimulation with TNF-related apoptosis-inducing ligand (TRAIL, 20 ng/ml) for 24 hours. Results In RA synovial tissue, compared with OA, we observed a stronger staining of ptpn2 in both the lining and the sublining layer by immunohistochemistry. On mRNA level we confirmed this overexpression in RA synovial tissue (2.0 fold, n = 4–5). In isolated RASF the constitutive mRNA level of PTPN2 was higher than in OASF (1.6 fold, p Levels of PTPN2 were further upregulated in RASF after stimulation with inflammatory cytokines such as TNFα (10 ng/ml, 24 hours, 3.1 fold, p Conclusions Our findings indicate that PTPN2, known to be involved in the pathogenesis of several autoimmune diseases, could be an important negative regulator of inflammation in RASF. Acknowledgement This work was supported by IMI BTCure, IAR and Masterswitch-FP7.
Florian Wiede - One of the best experts on this subject based on the ideXlab platform.
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t cell specific ptpn2 deficiency in nod mice accelerates the development of type 1 diabetes and autoimmune comorbidities
Diabetes, 2019Co-Authors: Florian Wiede, Thomas C Brodnicki, Pei Kee Goh, Yew Ann Leong, Gareth W Jones, Alan G Baxter, Simon Arnett Jones, Thomas W H KayAbstract:Genome-wide association studies have identified PTPN2 as an important non-MHC gene for autoimmunity. Single nucleotide polymorphisms that reduce PTPN2 expression have been linked with the development of various autoimmune disorders, including type 1 diabetes. The tyrosine phosphatase PTPN2 attenuates T-cell receptor and cytokine signaling in T cells to maintain peripheral tolerance, but the extent to which PTPN2 deficiency in T cells might influence type 1 diabetes onset remains unclear. NOD mice develop spontaneous autoimmune type 1 diabetes similar to that seen in humans. In this study, T-cell PTPN2 deficiency in NOD mice markedly accelerated the onset and increased the incidence of type 1 diabetes as well as that of other disorders, including colitis and Sjogren syndrome. Although PTPN2 deficiency in CD8+ T cells alone was able to drive the destruction of pancreatic β-cells and the onset of diabetes, T-cell-specific PTPN2 deficiency was also accompanied by increased CD4+ T-helper type 1 differentiation and T-follicular-helper cell polarization and increased the abundance of B cells in pancreatic islets as seen in human type 1 diabetes. These findings causally link PTPN2 deficiency in T cells with the development of type 1 diabetes and associated autoimmune comorbidities.
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reduced expression of phosphatase ptpn2 promotes pathogenic conversion of tregs in autoimmunity
Journal of Clinical Investigation, 2019Co-Authors: Mattias Svensson, Florian Wiede, Karen M Doody, Benjamin J Schmiedel, Sourya Bhattacharyya, Bharat Panwar, Shen Yang, Eugenio Santelli, Cristiano Sacchetti, Ravindra GujarAbstract:Genetic variants at the PTPN2 locus, which encodes the tyrosine phosphatase PTPN2, cause reduced gene expression and are linked to rheumatoid arthritis (RA) and other autoimmune diseases. PTPN2 inhibits signaling through the T cell and cytokine receptors, and loss of PTPN2 promotes T cell expansion and CD4- and CD8-driven autoimmunity. However, it remains unknown whether loss of PTPN2 in FoxP3+ regulatory T cells (Tregs) plays a role in autoimmunity. Here we aimed to model human autoimmune-predisposing PTPN2 variants, the presence of which results in a partial loss of PTPN2 expression, in mouse models of RA. We identified that reduced expression of Ptpn2 enhanced the severity of autoimmune arthritis in the T cell-dependent SKG mouse model and demonstrated that this phenotype was mediated through a Treg-intrinsic mechanism. Mechanistically, we found that through dephosphorylation of STAT3, PTPN2 inhibits IL-6-driven pathogenic loss of FoxP3 after Tregs have acquired RORγt expression, at a stage when chromatin accessibility for STAT3-targeted IL-17-associated transcription factors is maximized. We conclude that PTPN2 promotes FoxP3 stability in mouse RORγt+ Tregs and that loss of function of PTPN2 in Tregs contributes to the association between PTPN2 and autoimmunity.
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strain dependent differences in bone development myeloid hyperplasia morbidity and mortality in ptpn2 deficient mice
PLOS ONE, 2012Co-Authors: Florian Wiede, Michel L Tremblay, Sok Hui Chew, Catherine Julia Van Vliet, Ingrid J Poulton, Konstantinos Kyparissoudis, Tedjo Sasmono, Kim Y Loh, Dale I Godfrey, Natalie A SimsAbstract:Single nucleotide polymorphisms in the gene encoding the protein tyrosine phosphatase TCPTP (encoded by PTPN2) have been linked with the development of autoimmunity. Here we have used Cre/LoxP recombination to generate Ptpn2(ex2-/ex2-) mice with a global deficiency in TCPTP on a C57BL/6 background and compared the phenotype of these mice to Ptpn2(-/-) mice (BALB/c-129SJ) generated previously by homologous recombination and backcrossed onto the BALB/c background. Ptpn2(ex2-/ex2-) mice exhibited growth retardation and a median survival of 32 days, as compared to 21 days for Ptpn2(-/-) (BALB/c) mice, but the overt signs of morbidity (hunched posture, piloerection, decreased mobility and diarrhoea) evident in Ptpn2(-/-) (BALB/c) mice were not detected in Ptpn2(ex2-/ex2-) mice. At 14 days of age, bone development was delayed in Ptpn2(-/-) (BALB/c) mice. This was associated with increased trabecular bone mass and decreased bone remodeling, a phenotype that was not evident in Ptpn2(ex2-/ex2-) mice. Ptpn2(ex2-/ex2-) mice had defects in erythropoiesis and B cell development as evident in Ptpn2(-/-) (BALB/c) mice, but not splenomegaly and did not exhibit an accumulation of myeloid cells in the spleen as seen in Ptpn2(-/-) (BALB/c) mice. Moreover, thymic atrophy, another feature of Ptpn2(-/-) (BALB/c) mice, was delayed in Ptpn2(ex2-/ex2-) mice and preceded by an increase in thymocyte positive selection and a concomitant increase in lymph node T cells. Backcrossing Ptpn2(-/-) (BALB/c) mice onto the C57BL/6 background largely recapitulated the phenotype of Ptpn2(ex2-/ex2-) mice. Taken together these results reaffirm TCPTP's important role in lymphocyte development and indicate that the effects on morbidity, mortality, bone development and the myeloid compartment are strain-dependent.
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t cell protein tyrosine phosphatase attenuates stat3 and insulin signaling in the liver to regulate gluconeogenesis
Diabetes, 2010Co-Authors: Atsushi Fukushima, Michel L Tremblay, Florian Wiede, Benjamin J Shields, Sandra Galic, Kim Loh, Barbara C Fam, Matthew J Watt, Sofianos Andrikopoulos, Tony TiganisAbstract:OBJECTIVE Insulin-induced phosphatidylinositol 3-kinase (PI3K)/Akt signaling and interleukin-6 (IL-6)-instigated JAK/STAT3-signaling pathways in the liver inhibit the expression of gluconeogenic genes to decrease hepatic glucose output. The insulin receptor (IR) and JAK1 tyrosine kinases and STAT3 can serve as direct substrates for the T-cell protein tyrosine phosphatase (TCPTP). Homozygous TCPTP-deficiency results in perinatal lethality prohibiting any informative assessment of TCPTP's role in glucose homeostasis. Here we have used Ptpn2 +/− mice to investigate TCPTP's function in glucose homeostasis. RESEARCH DESIGN AND METHODS We analyzed insulin sensitivity and gluconeogenesis in chow versus high-fat–fed (HFF) Ptpn2 +/− and Ptpn2 +/+ mice and insulin and IL-6 signaling and gluconeogenic gene expression in Ptpn2 +/− and Ptpn2 +/+ hepatocytes. RESULTS HFF Ptpn2 +/− mice exhibited lower fasted blood glucose and decreased hepatic glucose output as determined in hyperinsulinemic euglycemic clamps and by the decreased blood glucose levels in pyruvate tolerance tests. The reduced hepatic glucose output coincided with decreased expression of the gluconeogenic genes G6pc and Pck1 and enhanced hepatic STAT3 phosphorylation and PI3K/Akt signaling in the fasted state. Insulin-induced IR-β–subunit Y1162/Y1163 phosphorylation and PI3K/Akt signaling and IL-6–induced STAT3 phosphorylation were also enhanced in isolated Ptpn2 +/− hepatocytes. The increased insulin and IL-6 signaling resulted in enhanced suppression of G6pc and Pck1 mRNA. CONCLUSIONS Liver TCPTP antagonises both insulin and STAT3 signaling pathways to regulate gluconeogenic gene expression and hepatic glucose output.