Homo sapiens
Ontology highlight
ABSTRACT:
OTHER RELATED OMICS DATASETS IN: E-GEOD-24736
PROVIDER: PRJNA132427 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Protein tyrosine phosphatase nonreceptor type 22 (PTPN22) gene segregates with most autoimmune diseases; its risk allele encodes overactive PTPN22 phosphatases that alter B cell receptor (BCR) signaling potentially involved in the regulation of central B cell tolerance. To assess whether PTPN22 risk allele affects the removal of developing autoreactive B cells, we tested by ELISA the reactivity of recombinant antibodies isolated from single B cells from asymptomatic healthy individuals carrying one or two PTPN22 risk allele(s). We found that new emigrant/transitional and mature naive B cells from PTPN22 risk allele carriers contained high frequencies of autoreactive clones compared to non-carrier control donors. Hence, a single PTPN22 risk allele has a dominant effect on altering autoreactive B cell counterselection, suggesting that early B cell tolerance checkpoint defects precede the onset of autoimmunity. In addition, gene array experiments comparing mature naïve B cells from healthy individuals carrying or not PTPN22 risk allele(s) revealed that the strength of association of PTPN22 for autoimmunity, second in importance only to the MHC, may not only be due to BCR signaling alteration but also to the regulation of other genes, which themselves have also been identified as involved in the development of autoimmune diseases. The PTPN22 risk allele is a single nucleotide change (cytidine to thymidine) at residue 1858, which results in a single amino acid substitution from arginine to tryptophan at position 620 of the PTPN22/Lyp protein. Data from mature naïve B cell populations from patients carrying 1 or 2 PTPN22 T alleles and non-carrier patients were compared in order to characterize the impact of PTPN22 polymorphism on B cell physiology. RNA was extracted from batch-sorted CD19+CD10-CD21+CD27- conventional mature naive B cells using the Absolutely RNA microprep kit (Stratagene). 100-200 ng of RNA was obtained per sample, and the quality of the purified RNA was assessed by the Bioanalyzer from Agilent. Using the Ovation biotin system kit from Nugen, 30-50ng of RNA was amplified and labeled to produce cDNA. Labeled cDNA was hybridized on chips containing the whole human genome (Human Genome U133 Plus 2.0 from Affymetrix).
2010-10-16 | E-GEOD-24736 | biostudies-arrayexpress
Project description:Protein tyrosine phosphatase nonreceptor type 22 (PTPN22) gene segregates with most autoimmune diseases; its risk allele encodes overactive PTPN22 phosphatases that alter B cell receptor (BCR) signaling potentially involved in the regulation of central B cell tolerance. To assess whether PTPN22 risk allele affects the removal of developing autoreactive B cells, we tested by ELISA the reactivity of recombinant antibodies isolated from single B cells from asymptomatic healthy individuals carrying one or two PTPN22 risk allele(s). We found that new emigrant/transitional and mature naive B cells from PTPN22 risk allele carriers contained high frequencies of autoreactive clones compared to non-carrier control donors. Hence, a single PTPN22 risk allele has a dominant effect on altering autoreactive B cell counterselection, suggesting that early B cell tolerance checkpoint defects precede the onset of autoimmunity. In addition, gene array experiments comparing mature naïve B cells from healthy individuals carrying or not PTPN22 risk allele(s) revealed that the strength of association of PTPN22 for autoimmunity, second in importance only to the MHC, may not only be due to BCR signaling alteration but also to the regulation of other genes, which themselves have also been identified as involved in the development of autoimmune diseases. The PTPN22 risk allele is a single nucleotide change (cytidine to thymidine) at residue 1858, which results in a single amino acid substitution from arginine to tryptophan at position 620 of the PTPN22/Lyp protein.
2010-10-16 | GSE24736 | GEO
Project description:Most autoreactive B cells are normally counterselected during early B cell development. To determine whether Toll-like receptors (TLRs) regulate the removal of autoreactive B lymphocytes, we tested the reactivity of recombinant antibodies from single B cells isolated from patients deficient for IL-1R-associated kinase (IRAK)-4, myeloid differentiation factor 88 (MyD88) and UNC-93B. Indeed, all TLRs except TLR3 require IRAK-4 and MyD88 to signal and UNC-93B-deficient cells are unresponsive to TLR3, TLR7, TLR8 and TLR9. All patients suffered from defective central and peripheral B cell tolerance checkpoints resulting in the accumulation of large numbers of autoreactive mature naïve B cells in their blood. Hence, TLR7, TLR8, and TLR9 may prevent the recruitment of developing autoreactive B cells in healthy donors. Paradoxically, IRAK-4-, MyD88- and UNC-93B-deficient patients did not display autoreactive antibodies in their serum nor developed autoimmune diseases, suggesting that IRAK-4, MyD88 and UNC-93B pathway blockade may thwart autoimmunity in humans.
2008-10-23 | GSE13300 | GEO
Project description:Most autoreactive B cells are normally counterselected during early B cell development. To determine whether Toll-like receptors (TLRs) regulate the removal of autoreactive B lymphocytes, we tested the reactivity of recombinant antibodies from single B cells isolated from patients deficient for IL-1R-associated kinase (IRAK)-4, myeloid differentiation factor 88 (MyD88) and UNC-93B. Indeed, all TLRs except TLR3 require IRAK-4 and MyD88 to signal and UNC-93B-deficient cells are unresponsive to TLR3, TLR7, TLR8 and TLR9. All patients suffered from defective central and peripheral B cell tolerance checkpoints resulting in the accumulation of large numbers of autoreactive mature naïve B cells in their blood. Hence, TLR7, TLR8, and TLR9 may prevent the recruitment of developing autoreactive B cells in healthy donors. Paradoxically, IRAK-4-, MyD88- and UNC-93B-deficient patients did not display autoreactive antibodies in their serum nor developed autoimmune diseases, suggesting that IRAK-4, MyD88 and UNC-93B pathway blockade may thwart autoimmunity in humans. Experiment Overall Design: RNA was extracted from 105-3.105 batch sorted new emigrant and mature naïve B cells isolated from donors using the Absolutely RNA microprep kit (Stratagene). 100-200 ng of RNA was obtained per sample, and the quality of the purified RNA was assessed by the Bioanalyzer from Agilent. Using the Ovation biotin system kit from Nugen, 30-50ng of RNA was amplified and labeled to produce cDNA. Labeled cDNA was hybridized on chips containing the whole human genome (Human Genome U133 2.0 from Affymetrix). Raw data from new emigrant (1 healthy donor) and mature naive (4 healthy donors) B cells were analyzed in order to determine the expression of some molecules involved in the TLR pathway in these B cell population in humans.
2008-11-13 | E-GEOD-13300 | biostudies-arrayexpress
Project description:Dominant protection from HLA-associated autoimmune disease is conferred by antigen specific regulatory T cells. Susceptibility and protection against human T cell mediated autoimmune diseases, including type I diabetes, multiple sclerosis and Goodpasture’s disease, is associated with particular Human Leukocyte Antigen (HLA) alleles. However, the mechanisms underpinning such HLA-mediated effects on self-tolerance, and the interplay with the responding autoreactive T cell repertoires, remain unclear. To address this central question, we investigated the molecular mechanism of Goodpasture’s disease, an HLA-linked autoimmune renal disorder characterized by an immunodominant CD4+ T cell self-epitope derived from the alpha3 chain of Type IV collagen (alpha3135-145). While HLA-DR15 confers a markedly increased disease risk (odds ratio 8.5), the protective HLA-DR1 allele (odds ratio 0.3) is dominantly protective in trans with HLA-DR15 (odds ratio 1.4). This dataset contains RAW data and database search results identifying the HLA-bound peptides from transgenic mice expressing either human HLA-DR1 or -DR15.
2017-05-04 | PXD005935 | Pride
Project description:IRAK-4- and MyD88-dependent pathways are essential for the removal of developing autoreactive B cells in humans
| PRJNA109873 | ENA
Project description:The presence of the PTPN22 risk variant (1858T) is associated to several autoimmune diseases including rheumatoid arthritis (RA). Despite a number of studies exploring the function of PTPN22 in T cells, the exact impact of the PTPN22 risk variant on T cell function in humans is still unclear. In this study, using RNA sequencing, we show that, upon TCR-activation, naïve CD4+ T cells carrying two PTPN22 risk alleles overexpress a limited number of genes including CFLAR and 4-1BB important for cytotoxic T cell differentiation. Moreover, an increased number of cytotoxic EOMES+ CD4+ T cells were observed in PTPN22 risk allele carriers, which negatively correlated with a decreased number of naïve T cells in older individuals. No difference in the frequency of other CD4+ T cell subsets (Th1, Th17, Tfh, Treg) was observed in PTPN22 risk allele carriers and Treg suppressive capacity was not altered. Finally, in synovial fluids of RA patients, an accumulation of EOMES+ CD4+ T cells was observed with a more pronounced production of Perforin-1 in PTPN22 risk allele carriers. Altogether, our data provide a novel mechanism of action of PTPN22 risk variant on CD4+ T-cell differentiation and identify EOMES+ CD4+ T cell as a relevant T cell subset in RA.
2018-02-27 | GSE94859 | GEO
Project description:This is system 1, the model with linear antigen uptake by pAPCs, described in the article:
Self-tolerance and Autoimmunity in a Regulatory T Cell Model.
Alexander HK, Wahl LM.
Bull Math Biol. 2010 Mar 2.
PMID:20195912, doi:10.1007/s11538-010-9519-2;
Abstract:
The class of immunosuppressive lymphocytes known as regulatory T cells (Tregs) has been identified as a key component in preventing autoimmune diseases. Although Tregs have been incorporated previously in mathematical models of autoimmunity, we take a novel approach which emphasizes the importance of professional antigen presenting cells (pAPCs). We examine three possible mechanisms of Treg action (each in isolation) through ordinary differential equation (ODE) models. The immune response against a particular autoantigen is suppressed both by Tregs specific for that antigen and by Tregs of arbitrary specificities, through their action on either maturing or already mature pAPCs or on autoreactive effector T cells. In this deterministic approach, we find that qualitative long-term behaviour is predicted by the basic reproductive ratio R (0) for each system. When R (0) 1, this equilibrium loses its stability and a stable non-trivial equilibrium appears. We interpret the absence of self-damaging populations at the trivial equilibrium to imply a state of self-tolerance, and their presence at the non-trivial equilibrium to imply a state of chronic autoimmunity. Irrespective of mechanism, our model predicts that Tregs specific for the autoantigen in question play no role in the system's qualitative long-term behaviour, but have quantitative effects that could potentially reduce an autoimmune response to sub-clinical levels. Our results also suggest an important role for Tregs of arbitrary specificities in modulating the qualitative outcome. A stochastic treatment of the same model demonstrates that the probability of developing a chronic autoimmune response increases with the initial exposure to self antigen or autoreactive effector T cells. The three different mechanisms we consider, while leading to a number of similar predictions, also exhibit key differences in both transient dynamics (ODE approach) and the probability of chronic autoimmunity (stochastic approach).
Originally created by libAntimony v1.4 (using libSBML 3.4.1)
2024-09-02 | BIOMD0000000289 | BioModels
Project description:This is system 2, the model with Michelis Menten type antigen uptake by pAPCs, described in the article:
Self-tolerance and Autoimmunity in a Regulatory T Cell Model.
Alexander HK, Wahl LM. Bull Math Biol.
2010 Mar 2.
PMID: 20195912
, doi: 10.1007/s11538-010-9519-2
;
Abstract:
The class of immunosuppressive lymphocytes known as regulatory T cells (Tregs) has been identified as a key component in preventing autoimmune diseases. Although Tregs have been incorporated previously in mathematical models of autoimmunity, we take a novel approach which emphasizes the importance of professional antigen presenting cells (pAPCs). We examine three possible mechanisms of Treg action (each in isolation) through ordinary differential equation (ODE) models. The immune response against a particular autoantigen is suppressed both by Tregs specific for that antigen and by Tregs of arbitrary specificities, through their action on either maturing or already mature pAPCs or on autoreactive effector T cells. In this deterministic approach, we find that qualitative long-term behaviour is predicted by the basic reproductive ratio R (0) for each system. When R (0) 1, this equilibrium loses its stability and a stable non-trivial equilibrium appears. We interpret the absence of self-damaging populations at the trivial equilibrium to imply a state of self-tolerance, and their presence at the non-trivial equilibrium to imply a state of chronic autoimmunity. Irrespective of mechanism, our model predicts that Tregs specific for the autoantigen in question play no role in the system's qualitative long-term behaviour, but have quantitative effects that could potentially reduce an autoimmune response to sub-clinical levels. Our results also suggest an important role for Tregs of arbitrary specificities in modulating the qualitative outcome. A stochastic treatment of the same model demonstrates that the probability of developing a chronic autoimmune response increases with the initial exposure to self antigen or autoreactive effector T cells. The three different mechanisms we consider, while leading to a number of similar predictions, also exhibit key differences in both transient dynamics (ODE approach) and the probability of chronic autoimmunity (stochastic approach).
Originally created by libAntimony v1.4 (using libSBML 3.4.1)
2024-09-02 | BIOMD0000000290 | BioModels