Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0003873 (rheumatoid arthritis)
 53,068 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The third hypervariable region (HV3) of HLA-DRB1*0401 helps the development of severe rheumatoid arthritis by an unknown mechanism. To test whether the third hypervariable region of HLA-DRB1*0401 may shape the T cell repertoire, we studied proliferative responses to peptides encompassing the third hypervariable region of seven HLA-DRB1 alleles in normal subjects and patients with rheumatoid arthritis. We found that, in general, there is no tolerance to peptides from the third hypervariable region of self-HLA-DRB1 alleles. However, a peptide from the third hypervariable region of DRB1*0401 (DRB1*0401 HV3 peptide) is tolerated in people who express HLA-DRB1*0401. Indeed, PBMCs from people who express DRB1*0401 do not proliferate to DRB1*0401 HV3 peptide. Conversely, people who express DRB1*1501 respond to DRB1*0401 HV3 peptide. Finally, people who express both DRB1*0401 (nonresponder haplotype) and DRB1*1501 (high responder haplotype) do not respond to DRB1 HV3 peptide, thus demonstrating tolerance. Therefore, the third hypervariable region of HLA-DRB1*0401 shapes the T cell repertoire.
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PMID:Tolerance to a self-peptide from the third hypervariable region of HLA DRB1*0401 in rheumatoid arthritis patients and normal subjects. 796 84

One of the genetic components of seropositive rheumatoid arthritis has been mapped to a short sequence stretch in the third hypervariable region of the HLA-DRB1 gene. A new concept has emerged, proposing that the shared-sequence motif is functional in determining the clinical patterns of rheumatoid arthritis and the severity of the disease in a codominant mode. Patients with a double dose of the shared sequence tend to have more serious disease manifestations, suggesting a model in which the genetic element is involved in perpetuating the disease. The pathogenetic model in which the shared epitope selectively binds and presents an arthritogenic peptide appears too simplistic to account for these findings. Our understanding of how the shared epitope may contribute to forming the molecular complex of the T-cell receptor, peptide, and HLA-DR molecule is advancing. Molecular analyses of the synovial T-cell infiltrate continue to define the various components involved in recruiting T cells to the site of synovial inflammation. Adhesion molecules, predominantly the endothelial cell ligands vascular adhesion molecule 1 and endothelial leukocyte adhesion molecule 1, attract phenotypically selected T cells with a wide spectrum of specificities. The rheumatoid factor-positive B cells may be important antigen-presenting cells in the joint and may activate T cells with many different specificities. Rheumatoid factor immunoglobulin genes show clear evidence of somatic mutation, indicating a T cell-dependent, antigen-driven process. Thus, multiple factors contribute to the composition of the inflammatory infiltrate and may well modulate the repertoire of T cells recruited to the tissue.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Interplay of T lymphocytes and HLA-DR molecules in rheumatoid arthritis. 845 67

Most patients with rheumatoid arthritis express particular HLA-DR alleles. The DRbeta1 chains of these alleles share a highly homologous amino acid motif, in their third hypervariable (HV3) region, and this motif seems to help the development of rheumatoid arthritis via unknown mechanisms. In an attempt to identify a ligand of this motif, we screened bacterial proteins. HV3 peptides from HLA-DRB1 alleles containing a QKRAA or RRRAA motif bound the 70-kD heat shock protein (HSP) from Escherichia coli, dnaK. In lymphoblastoid cells homozygous for these same HLA-DRB1 alleles the constitutive 70-kD HSP, HSP73, that targets selected proteins to lysosomes coprecipitated with HLA-DR. Thus the QKRAA and RRRAA amino acid motifs of HLA-DR mediate binding of HLA-DR to HSP73. This property may influence the intracellular route, processing or peptide associations of the HLA-DRbeta1 chain in these two rheumatoid arthritis-associated alleles.
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PMID:HLA-DR4 and HLA-DR10 motifs that carry susceptibility to rheumatoid arthritis bind 70-kD heat shock proteins. 980 21

Rheumatoid arthritis is characterized by a strong HLA-DRB1 association and a histologic picture consistent with an antigen recognition event by tissue-infiltrating T cells. Basic immunology has seen major progress in the understanding of the T-cell receptor-MHC-antigen interaction; however, the role of T cells and disease-associated HLA-DRB1 alleles in rheumatoid arthritis remains elusive. Recent studies on the genetics of the HLA-DRB1 association and the diversity of the repertoire of synovial T cells, and treatment studies with T-cell depleting antibodies, have suggested that the model of T cells recognizing an arthritogenic antigen in association with a HLA-DR molecule is too simplistic. The findings are more consistent with a regulatory role of T cells. Patients with rheumatoid arthritis have a unique T-cell repertoire that not only reflects the influence of disease-associated HLA-DRB1 alleles but also is greatly skewed by the clonal expansion of few CD4+ and CD8+ T-cell specificities. Understanding these repertoire changes appears to be promising not only in permitting understanding of the pathogenesis of this disease but also in designing T-cell-targeted treatment strategies.
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PMID:T cells in rheumatoid arthritis. Paradigms and facts. 861 93

The frequency of HLA-DRB1 alleles was determined in 68 Caucasoid patients with polymyalgia rheumatica (PMR) and 140 controls using polymerase chain reaction (PCR) sequence-specific oligonucleotide typing. In keeping with previous studies, an increased frequency of DRB1*04 was observed in patients [55.9% vs 35.0%, odds ratio (OR) 2.4, 95% confidence interval (CI) 1.3-4.4]. HLA-DRB1*0101 frequency was also increased in patients, although less confidence could be placed on this association (19.1% vs 14.3%, OR 1.4, 95% CI 0.6-3.3). HLA-DRB1*04 subtyping indicated that the frequencies of both DRB1*0401 (38.2% vs 22.1%, OR 2.2, 95% CI 1.0-4.3) and DRB1*0404 (16.2% vs 5.0%, OR 3.7, 95% CI 1.2-11.1) were specifically raised. An increased frequency of the RA shared epitope (QKRAA/QRRAA) was also observed in this group (75.0% vs 44.2%, OR 3.8, 95% CI 1.9-7.6). When the analysis was restricted to only DRB1*04-negative patients and controls, the frequencies of DRB1*0301, *11 and *08 were marginally raised. However, no obvious relationship appeared to exist between PMR susceptibility and DRB1 alleles carrying the DYF conserved epitope in the second hypervariable region. Autoantibodies to thyroid antigens were present in 23% of patients. An increased frequency of DRB1*0301 was observed in patients with thyroid microsomal antibodies compared to those without (54.5% vs 24.6%, OR 3.7, 95% CI 0.8-17.0). This increase was not observed in patients with thyroglobulin autoantibodies. These data indicate that both DRB1*0401 and *0404 are associated with PMR, and that this may extend to include DRB1*0101. The immunogenetic profile of susceptibility markers in this condition appears to be similar to that in rheumatoid arthritis.
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PMID:Polymyalgia rheumatica is associated with both HLA-DRB1*0401 and DRB1*0404. 867 May 95

The major histocompatibility complex class II genes play an important role in the genetic predisposition to many autoimmune diseases. In the case of rheumatoid arthritis (RA), the human leukocyte antigen (HLA)-DRB1 locus has been implicated in the disease predisposition. The "shared epitope" hypothesis predicts that similar motifs within the third hypervariable (HV3) regions of some HLA-DRB1 alleles are responsible for the class II-associated predisposition to RA. Using a line of transgenic mice expressing the DQB1*0302/DQA1*0301 (DQ8) genes in the absence of endogenous mouse class II molecules, we have analyzed the antigenicity of peptides covering the HV3 regions of RA-associated and nonassociated DRB1 molecules. Our results show that a correlation exists between proliferative response to peptides derived from the HV3 regions of DRB1 chains and nonassociation of the corresponding alleles with RA predisposition. While HV3 peptides derived from nonassociated DRB1 molecules are highly immunogenic in DQ8 transgenic mice, all the HV3 peptides derived from RA-associated DRB1 alleles fail to induce a DQ8-restricted T-cell response. These data suggest that the role of the "shared epitope" in RA predisposition may be through the shaping of the T-cell repertoire.
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PMID:Immune response of HLA-DQ8 transgenic mice to peptides from the third hypervariable region of HLA-DRB1 correlates with predisposition to rheumatoid arthritis. 870 Aug 41

Rheumatoid arthritis (RA) and spondylarthropathies are the most frequent chronic inflammatory arthritides. RA is a potentially severe disease which causes a functional handicap in nearly half the patients 10 years after the first clinical symptoms. However RA is a heterogenous disorder characterized by wide variations in clinical manifestations, disease course and response to therapy. No prognosis factor has been identified and universally accepted and validated. Markers of prognosis would be highly appreciated by clinicians who could then more closely adapt their management decisions to the disease potential. Clinical and biological data collected to date have provided a limited amount of information. Nevertheless, ESR, CRP and rheumatoid factor titer appeared to be the most powerful available indicators of prognosis at the early stage of the disease. Recent progress in molecular biology strongly suggests that genetic markers (HLA-DRB1 alleles) could be correlated with disease severity and it would appear possible to distinguish immunogenetically homogeneous subpopulations of patients with RA. Serum concentrations of specific cartilage and bone molecules reflecting tissue turnover could correlate to rate of joint destruction. Finally a combination of the most pertinent markers could determine a "score of severity" of the disease. In spondylarthropathies, limited information is available at present. The variables which were usually correlated with disease severity are: onset before 16 years of age, hip arthritis, ESR, limitation of lumbar spine, sausage-like finger or toe, oligoarthritis, poor efficacy of nonsteroidal antiinflammatory drugs and rapid evolution during the first 2 years. Genetic factors could also have prognosis value that should be clarified.
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PMID:[Prognostic factors in early inflammatory arthritis]. 873 44

The major histocompatibility complex class III tumor necrosis factor-lymphotoxin (TNF-LT) region (6p21.3) was investigated as a possible susceptibility locus for rheumatoid arthritis (RA). Inheritance of five TNF microsatellite markers was determined in 50 multiplex families. Overall, 47 different haplotypes were observed. One of these, the TNF a6, b5, c1, d3, e3 (H1) haplotype, was present in 35.3% of affected, but in only 20.5% of unaffected, individuals (P < .005). This haplotype accounted for 21.5% of the parental haplotypes transmitted to affected offspring and only 7.3% not transmitted to affected offspring (P = .0003). The TNF a6 and TNF c1 alleles were individually associated with RA (P = .0005 and .0008, respectively), as were the HLA-DRB1 "shared epitope" (SE) (P = .0001) and HLA-DRB1*0401 (P = .0018). Both univariate and bivariate conditional logistic regression analysis showed significant effects of TNF c1 and SE in increasing risk to RA (P < .001). Stratification by the presence of SE indicated an independent effect of the TNFc1 allele (P = .0003) and the HLA A1, B8, DR3 extended haplotype (always TNFa2, b3, c1, d1, e3) (P = .0027) in SE heterozygotes, while the H1 haplotype was associated with RA in SE homozygotes (P = .0018). The TNF-LT region appears to influence susceptibility to RA, distinct from HLA-DR.
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PMID:Genetic variability in the tumor necrosis factor-lymphotoxin region influences susceptibility to rheumatoid arthritis. 875 69

Our aim was to compare the sensitivity of 4 analytical methods to detect linkage to a known disease susceptibility locus, HLA-DRB1, in 100 rheumatoid arthritis sibling pair families with incomplete parental genotype information. Genotypes for the HLA-DRB1 and HLA-A loci were analyzed using (1) identity-by-descent (IBD), considering inheritance of maternal and paternal alleles separately; (2) maximum likelihood score-IBD (MLS-IBD), which infers missing parental genotypes; (3) identity-by-state (IBS), which does not require parental genotypes; and (4) transmission disequilibrium test (TDT), which uses affected offspring with a heterozygous parent. Due to the small number of informative meoisis for HLA-DRB1, the IBD analysis was not significant for linkage (p = 0.014). HLA-A was more informative (p = 0.0002). The MLS-IBD method for HLA-DRB1 (p = 0.00004) and HLA-A (p < or = 0.00001) was significant. Using IBS both loci gave highly significant evidence of linkage, (p < < 0.00001). The TDT detected HLA-DRB1*0401 as the allele associated with RA; no HLA-A allele was associated. Thus, sib pair families with limited parental genotypes can be used to detect disease susceptibility loci, but when selecting the method of analysis the informativeness of the markers should be taken into account.
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PMID:The sensitivity of different analytical methods to detect disease susceptibility genes in rheumatoid arthritis sibling pair families. 900 41

Susceptibility to developing rheumatoid arthritis (RA) maps to a highly conserved amino acid motif located in the third hypervariable region of different HLA-DRB1 chains. This motif, namely QKRAA, QRRAA, or RRRAA, helps the development of RA by an unknown mechanism. The QKRAA motif predisposes to more severe disease than the QRRAA or RRRAA motifs. The QKRAA motif carries particular properties: it is a strong B- and T-cell epitope, it shapes the T cell repertoire, it is overrepresented in protein databases, and it is a binding motif for bacterial and human 70-kDa heat-shock proteins. In this article, we propose different models to explain how the QKRAA motif might contribute to RA.
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PMID:Molecular mechanisms involved in the association of HLA-DR4 and rheumatoid arthritis. 904 13


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