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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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protein tyrosine phosphatase nonreceptor type 2 an important regulator of lnterleukin 6 production in rheumatoid arthritis synovial fibroblasts
Arthritis & Rheumatism, 2015Co-Authors: Borbala Aradi, Michael Scharl, Maria Filkova, Masaru Kato, B A Michel, Edit I Buzas, Emmanuel Karouzakis, K Klein, Christoph Kolling, Astrid JungelAbstract:Objective This article is protected by copyright. All rights reserved. Methods Synovial tissues from RA and osteoarthritis (OA) were stained for PTPN2. Synovial fibroblasts (SF), were stimulated with TNF and IL1β, LPS, TRAIL or thapsigargin. Expression of PTPN2 in SF or PBMCs was analyzed by Real-time PCR and Western blotting. Cell death, the release of IL-6 and IL-8 and the induction of autophagy were analyzed after PTPN2 silencing. MeDIP analysis was used to check DNA methylation-regulated gene expression of PTPN2. Results PTPN2 was significantly overexpressed in synovial tissues of RA compared to OA. Patients treated with anti-TNF therapy showed significantly reduced staining for PTPN2 compared with patients treated with non-biologics. In RASF, PTPN2 expression was higher compared to OASF. This differential expression is not regulated by DNA methylation. PTPN2 was further upregulated after stimulation with TNF, TNF combined with IL1β and LPS. There was no significant difference in basal PTPN2 expression in PBMCs from patients with RA, ankylosing spondylitis, systemic lupus erythematosus and healthy controls. Most interestingly, PTPN2 silencing in RASF significantly increased the production of the inflammatory cytokine IL-6 but did not affect levels of IL-8. Moreover, functional analysis showed that high PTPN2 levels contribute to the increased apoptosis resistance of RASF and increased autophagy. Conclusion This is the first study on PTPN2 in RASF showing that PTPN2 regulates IL-6 production, cell death and autophagy. This indicates that PTPN2 is linked to the pathogenesis of RA via synovial fibroblasts. This article is protected by copyright. All rights reserved.
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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
Borbala Aradi - One of the best experts on this subject based on the ideXlab platform.
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protein tyrosine phosphatase nonreceptor type 2 an important regulator of lnterleukin 6 production in rheumatoid arthritis synovial fibroblasts
Arthritis & Rheumatism, 2015Co-Authors: Borbala Aradi, Michael Scharl, Maria Filkova, Masaru Kato, B A Michel, Edit I Buzas, Emmanuel Karouzakis, K Klein, Christoph Kolling, Astrid JungelAbstract:Objective This article is protected by copyright. All rights reserved. Methods Synovial tissues from RA and osteoarthritis (OA) were stained for PTPN2. Synovial fibroblasts (SF), were stimulated with TNF and IL1β, LPS, TRAIL or thapsigargin. Expression of PTPN2 in SF or PBMCs was analyzed by Real-time PCR and Western blotting. Cell death, the release of IL-6 and IL-8 and the induction of autophagy were analyzed after PTPN2 silencing. MeDIP analysis was used to check DNA methylation-regulated gene expression of PTPN2. Results PTPN2 was significantly overexpressed in synovial tissues of RA compared to OA. Patients treated with anti-TNF therapy showed significantly reduced staining for PTPN2 compared with patients treated with non-biologics. In RASF, PTPN2 expression was higher compared to OASF. This differential expression is not regulated by DNA methylation. PTPN2 was further upregulated after stimulation with TNF, TNF combined with IL1β and LPS. There was no significant difference in basal PTPN2 expression in PBMCs from patients with RA, ankylosing spondylitis, systemic lupus erythematosus and healthy controls. Most interestingly, PTPN2 silencing in RASF significantly increased the production of the inflammatory cytokine IL-6 but did not affect levels of IL-8. Moreover, functional analysis showed that high PTPN2 levels contribute to the increased apoptosis resistance of RASF and increased autophagy. Conclusion This is the first study on PTPN2 in RASF showing that PTPN2 regulates IL-6 production, cell death and autophagy. This indicates that PTPN2 is linked to the pathogenesis of RA via synovial fibroblasts. This article is protected by copyright. All rights reserved.
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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.
Astrid Jungel - One of the best experts on this subject based on the ideXlab platform.
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protein tyrosine phosphatase nonreceptor type 2 an important regulator of lnterleukin 6 production in rheumatoid arthritis synovial fibroblasts
Arthritis & Rheumatism, 2015Co-Authors: Borbala Aradi, Michael Scharl, Maria Filkova, Masaru Kato, B A Michel, Edit I Buzas, Emmanuel Karouzakis, K Klein, Christoph Kolling, Astrid JungelAbstract:Objective This article is protected by copyright. All rights reserved. Methods Synovial tissues from RA and osteoarthritis (OA) were stained for PTPN2. Synovial fibroblasts (SF), were stimulated with TNF and IL1β, LPS, TRAIL or thapsigargin. Expression of PTPN2 in SF or PBMCs was analyzed by Real-time PCR and Western blotting. Cell death, the release of IL-6 and IL-8 and the induction of autophagy were analyzed after PTPN2 silencing. MeDIP analysis was used to check DNA methylation-regulated gene expression of PTPN2. Results PTPN2 was significantly overexpressed in synovial tissues of RA compared to OA. Patients treated with anti-TNF therapy showed significantly reduced staining for PTPN2 compared with patients treated with non-biologics. In RASF, PTPN2 expression was higher compared to OASF. This differential expression is not regulated by DNA methylation. PTPN2 was further upregulated after stimulation with TNF, TNF combined with IL1β and LPS. There was no significant difference in basal PTPN2 expression in PBMCs from patients with RA, ankylosing spondylitis, systemic lupus erythematosus and healthy controls. Most interestingly, PTPN2 silencing in RASF significantly increased the production of the inflammatory cytokine IL-6 but did not affect levels of IL-8. Moreover, functional analysis showed that high PTPN2 levels contribute to the increased apoptosis resistance of RASF and increased autophagy. Conclusion This is the first study on PTPN2 in RASF showing that PTPN2 regulates IL-6 production, cell death and autophagy. This indicates that PTPN2 is linked to the pathogenesis of RA via synovial fibroblasts. This article is protected by copyright. All rights reserved.
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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.
Donald W Bowden - One of the best experts on this subject based on the ideXlab platform.
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association of protein tyrosine phosphatase 1b gene polymorphisms with measures of glucose homeostasis in hispanic americans the insulin resistance atherosclerosis study iras family study
Diabetes, 2004Co-Authors: Nicholette D Palmer, Jennifer L Bento, Josyf C Mychaleckyj, Carl D Langefeld, Joel K Campbell, Jill M Norris, Stephen M Haffner, Richard N Bergman, Donald W BowdenAbstract:Protein tyrosine phosphatase (PTP)-1B, encoded by the PTPN1 gene, catalyzes the dephosphorylation of proteins at tyrosyl residues. PTP-1B has been implicated in negatively regulating insulin signaling by dephosphorylating the phosphotyrosine residues of the insulin receptor. The genetic contribution of PTPN1 to measures of glucose homeostasis has been assessed in 811 Hispanic subjects from the Insulin Resistance Atherosclerosis Study Family Study (IRASFS). Thirty-five single nucleotide polymorphisms (SNPs) spanning 161 kb and containing the PTPN1 gene were genotyped and tested for association. All 20 SNPs with minor allele frequencies >0.1 in a single haplotype block covering the PTPN1 genomic sequence show significant association with the insulin sensitivity index ( S i) ( P = 0.044–0.003) and fasting glucose ( P = 0.029 to <0.001). In contrast, there is no evidence for association of PTPN1 polymorphisms with acute insulin response (a measure of β-cell function). Haplotype analysis of eight SNP haplotypes that have independently been shown to be associated with type 2 diabetes risk and protection in Caucasian type 2 diabetic subjects are associated with lower ( P = 0.007) and higher ( P = 0.0002) S i and higher ( P = 0.00007) and lower ( P = 0.001) fasting glucose, respectively, in the IRASFS. This comprehensive genetic analysis of PTPN1 reveals significant association with metabolic traits consistent with the proposed in vivo role for the PTP-1B protein.
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association of protein tyrosine phosphatase 1b gene polymorphisms with type 2 diabetes
Diabetes, 2004Co-Authors: Jennifer L Bento, Nicholette D Palmer, Josyf C Mychaleckyj, Carl D Langefeld, Leslie A Lange, Stephen S Rich, Barry I Freedman, Donald W BowdenAbstract:The PTPN1 gene codes for protein tyrosine phosphatase 1B (PTP1B) (EC 3.1.3.48), which negatively regulates insulin signaling by dephosphorylating the phosphotyrosine residues of the insulin receptor kinase activation segment. PTPN1 is located in 20q13, a genomic region linked to type 2 diabetes in multiple genetic studies. Surveys of the gene have previously identified only a few uncommon coding single nucleotide polymorphisms (SNPs). We have carried out a detailed association analysis of 23 noncoding SNPs spanning the 161-kb genomic region, which includes the PTPN1 gene. These SNPs have been assessed for association with type 2 diabetes in two independently ascertained collections of Caucasian subjects with type 2 diabetes and two control groups. Association is observed between multiple SNPs and type 2 diabetes. The most consistent evidence for association occurred with SNPs spanning the 3' end of intron 1 of PTPN1 through intron 8 (P values ranging from 0.043 to 0.004 in one case-control set and 0.038-0.002 in a second case-control set). Analysis of the combined case-control data increased the evidence of SNP association with type 2 diabetes (P = 0.005-0.0016). All of the associated SNPs lie in a single 100-kb haplotype block that encompasses the PTPN1 gene. Analysis of haplotypes indicates a significant difference between haplotype frequencies in type 2 diabetes case and control subjects (P = 0.0035-0.0056), with one common haplotype (36%) contributing strongly to the evidence for association with type 2 diabetes. Odds ratios calculated from single SNP or haplotype data are in the proximity of 1.3. Haplotype-based calculation of population-attributable risk (PAR) results in an estimated PAR of 17-20% based on different models and assumptions. These results suggest that PTPN1 is a significant contributor to type 2 diabetes susceptibility in the Caucasian population. This risk is likely due to noncoding polymorphisms.
Elizabeth A White - One of the best experts on this subject based on the ideXlab platform.
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PTPN14 degradation by high risk human papillomavirus e7 limits keratinocyte differentiation and contributes to hpv mediated oncogenesis
Proceedings of the National Academy of Sciences of the United States of America, 2019Co-Authors: Joshua Hatterschide, Amelia E Bohidar, Miranda Grace, Tara J Nulton, Hee Won Kim, Brad Windle, Iain M Morgan, Karl Munger, Elizabeth A WhiteAbstract:High-risk human papillomavirus (HPV) E7 proteins enable oncogenic transformation of HPV-infected cells by inactivating host cellular proteins. High-risk but not low-risk HPV E7 target PTPN14 for proteolytic degradation, suggesting that PTPN14 degradation may be related to their oncogenic activity. HPV infects human keratinocytes but the role of PTPN14 in keratinocytes and the consequences of PTPN14 degradation are unknown. Using an HPV16 E7 variant that can inactivate retinoblastoma tumor suppressor (RB1) but cannot degrade PTPN14, we found that high-risk HPV E7-mediated PTPN14 degradation impairs keratinocyte differentiation. Deletion of PTPN14 from primary human keratinocytes decreased keratinocyte differentiation gene expression. Related to oncogenic transformation, both HPV16 E7-mediated PTPN14 degradation and PTPN14 deletion promoted keratinocyte survival following detachment from a substrate. PTPN14 degradation contributed to high-risk HPV E6/E7-mediated immortalization of primary keratinocytes and HPV+ but not HPV- cancers exhibit a gene-expression signature consistent with PTPN14 inactivation. We find that PTPN14 degradation impairs keratinocyte differentiation and propose that this contributes to high-risk HPV E7-mediated oncogenic activity independent of RB1 inactivation.
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PTPN14 degradation by high risk human papillomavirus e7 limits keratinocyte differentiation and contributes to hpv mediated oncogenesis
bioRxiv, 2018Co-Authors: Joshua Hatterschide, Amelia E Bohidar, Miranda Grace, Tara J Nulton, Brad Windle, Iain M Morgan, Karl Munger, Elizabeth A WhiteAbstract:High-risk human papillomavirus (HPV) E7 proteins enable oncogenic transformation of HPV-infected cells by inactivating host cellular proteins. High-risk but not low-risk HPV E7 target PTPN14 for proteolytic degradation, suggesting that PTPN14 degradation may be related to their oncogenic activity. HPV infects human keratinocytes but the role of PTPN14 in keratinocytes and the consequences of PTPN14 degradation are unknown. Using an HPV16 E7 variant that can inactivate RB1 but cannot degrade PTPN14 we found that high-risk HPV E7-mediated PTPN14 degradation impairs keratinocyte differentiation. Deletion of PTPN14 from primary human keratinocytes decreased keratinocyte differentiation gene expression. Related to oncogenic transformation, both HPV16 E7-mediated PTPN14 degradation and PTPN14 deletion promoted keratinocyte survival following detachment from a substrate. PTPN14 degradation contributed to high-risk HPV E6/E7-mediated immortalization of primary keratinocytes and HPV-positive but not HPV-negative cancers exhibit a gene expression signature consistent with PTPN14 inactivation. We find that PTPN14 degradation impairs keratinocyte differentiation and propose that this contributes to high-risk HPV E7-mediated oncogenic activity independent of RB1 inactivation.