Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0003873 (
rheumatoid arthritis
)
53,068
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Human leucocyte antigen (HLA) class II molecules have been shown to be associated with predisposition to
rheumatoid arthritis
(RA). We generated HLA-DR and DQ transgenic mice that lacked endogenous class II molecules to study the interaction between the DR and DQ molecules and define the immunologic mechanisms in
rheumatoid arthritis
. Using collagen-induced arthritis (CIA) as an experimental model for inflammatory polyarthritis, we show that both DQ and DR are involved in predisposition or resistance to arthritis. Our studies suggest that polymorphism in DQB1 genes may determine predisposition to RA while the
DRB1
polymorphism may dictate severity/protection of the disease. These mice provide powerful tools to develop immunotherapeutic protocols.
...
PMID:Association of MHC and rheumatoid arthritis. Regulatory role of HLA class II molecules in animal models of RA: studies on transgenic/knockout mice. 1109 29
Inherited susceptibility to
rheumatoid arthritis
(RA) is associated with the
DRB1
genes encoding the human leukocyte antigen (HLA)-DR4 and HLA-DR1 molecules. Transgenic mice expressing these major histocompatibility complex (MHC) class II molecules have been developed to generate humanized models for RA. The relevance of these models for understanding RA will be discussed.
...
PMID:Association of MHC and rheumatoid arthritis. HLA-DR4 and rheumatoid arthritis: studies in mice and men. 1109 29
It is hypothesized that autoimmune diseases manifest when tolerance to self-Ags fails. One possible mechanism to break tolerance is presentation of self-Ag in an altered form. Most Ags are presented by APCs via the traditional presentation pathway that includes "epitope editing" by intracellular HLA-DM, a molecule that selects for stable MHC-peptide complexes. We were interested in testing the hypothesis that autoreactive MHC-peptide complexes may reach the cell surface by an alternate pathway without being edited by HLA-DM. We selected a cartilage autoantigen human cartilage glycoprotein 39 to which T cell responses are observed in
rheumatoid arthritis
(RA) patients and some DR(*)04 healthy subjects. RA is genetically associated with certain
DRB1
alleles, including
DRB1
(*)0401 but closely related allele
DRB1
(*)0402 is either neutral or mildly protective with respect to RA. We generated human B lymphoblastoid cell line cells expressing DR(*)0401 or DR(*)0402 in the presence or absence of intracellular HLA-DM and assessed their ability to present a candidate autoantigen, human cartilage glycoprotein 39. Our results show that the presence of intracellular HLA-DM is critical for presentation of this autoantigen to CD4(+) T cell hybridomas generated from DR(*)04-transgenic mice. Presentation of an autoantigen by the traditional HLA-DM-dependent pathway has implications for Ag presentation events in RA.
...
PMID:Autoantigenic HCgp39 epitopes are presented by the HLA-DM-dependent presentation pathway in human B cells. 1112 74
We have reviewed the literature on the association of HLA class II with
rheumatoid arthritis
(RA). Strong linkage disequilibrium among DQB1, DQA1 and
DRB1
alleles makes it difficult to evaluate the individual contribution of each locus. Nonetheless, there is a strong case for the role of DQB1*03 and *04 combined with DQA1*03 in susceptibility to severe RA while DQB1*0501 combined with DQA1*0101 and *0104 weakly predisposes to a mild form of RA. However, it is also clear that DRB1*0401 has a particular role in predisposition to the most severe form of the disease while other
DRB1
alleles might provide protection. We would like to propose that in RA, as in type I diabetes, both DQ and DR loci contribute to predisposition to the disease.
...
PMID:HLA class II association with rheumatoid arthritis: facts and interpretations. 1116 80
On the basis of our extensive studies on collagen induced arthritis in HLA class II transgenic mice, we proposed a hypothesis to explain role of shared epitope in
rheumatoid arthritis
(RA) association. According to our hypothesis, complementation between both DQ and DR molecules is required for susceptibility or protection from disease. While certain DQ alleles predispose individuals to RA,
DRB1
molecule can modulate disease by shaping T-cell repertoire in the thymus by providing self-peptides and presented by DQ molecules. Using A beta o.DQ8 transgenic mice, we tested ability of peptides derived from HV3 of DR molecules, implicated in RA positively or negatively, to activate T cells. While the peptides derived from RA susceptible DR molecule were poor binders and poor in activating T cells, the peptides derived from RA resistant DR molecules were high affinity binders and efficient T-cell activators. Our experiments suggest that high affinity DR peptides could induce tolerance to autoimmunity while the low affinity peptides could be permissive to autoimmunity. Using peptide from DRB1*0402 molecule, known to be associated with resistance to RA, prior to induction of collagen induced arthritis prevents the onset of disease. Thus, self-peptides derived from HLA molecules could potentially generate tolerance or autoimmunity depending on their binding affinity with HLA molecules.
...
PMID:Autoimmunity versus tolerance: analysis using transgenic mice. 1116 96
Rheumatoid arthritis
(RA) is a chronic inflammatory joint disease with a multifactorial genetic basis. However, pathogenic genes for RA other than the human leukocyte antigen (HLA)-
DRB1
gene have yet to be identified. Here, we investigated whether there is a second susceptibility locus for RA within the human major histocompatibility complex using 18 microsatellite markers distributed from the centromeric (HSET) to the telomeric end (P5-15) of the 3.6-Mb HLA region. Statistical studies of associated alleles on each microsatellite locus showed that one pathogenic gene for RA in the HLA region is localized in the
DRB1
gene, as expected. Further, a second susceptibility gene of RA was suggested to be present in the HLA class III region, narrowed to 70 kb, that is just telomeric of the TNF gene cluster (TNFA and LTA) and that is located between the microsatellites TNFa and C1-2-A. In this critical segment, four expressed genes have been thus far identified, NFKBIL1 (IkappaBL), ATP6G, BAT1, and MICB, all of which are candidate genes for determining susceptibility to RA. These results exclude the possibility of involvement of the TNFA genes (TNF-alpha) in the development of RA, which was suggested previously to be a strong candidate for RA in the class III region.
...
PMID:A second susceptibility gene for developing rheumatoid arthritis in the human MHC is localized within a 70-kb interval telomeric of the TNF genes in the HLA class III region. 1117 Jul 43
To examine the genetic contribution of HLA and non-HLA genes in the etiopathogenesis of
rheumatoid arthritis
(RA), 60 Caucasian multiplex families were identified and DNA analyzed for over 52 markers including
DRB1
, DQA1 and DQB1 alleles. Many of the markers were chosen because of close proximity to candidate genes suggested by previous studies or models of pathogenesis. Sibling pair analysis (SIBPAL), relative pair analysis (RELPAL) and linkage studies using two different models of inheritance suggested linkage for the MHC and two additional chromosomal regions: chromosome 2 (D2S443 near CD8 and IGk; 2p13-2p11.1), and chromosome 15 (CYP19-estrogen synthase; 15q15). No support was found for two chromosomal regions, 1p36 and 3q13, recently suggested by other studies. We used transmission disequilibrium testing (TDT), conditional logistic regression, and segregation analysis to study the contributions that the shared epitope and TNF-c have in contributing to risk for RA. These studies provide additional evidence that the association of HLA alleles in RA patients from multiplex families is similar to that observed in sporadic disease, suggest candidate regions for further analysis and find additional support for an association of TNF-c alleles with RA susceptibility.
...
PMID:Genetic analysis of multiplex rheumatoid arthritis families. 1119 2
Whereas the
DRB1
alleles have well-established associations with
rheumatoid arthritis
(RA), the DQ and DP alleles are of more controversial relevance to RA. Early studies of the DQB1 genes in RA determined the frequencies of the two DQB1*03 subtypes that are in linkage disequilibrium with DR4, DQB1*0301 (DQw7) and *0302 (DQw8). Their results are conflicting and difficult to interpret because molecular biology techniques for determining DR4 specificity polymorphism were not available at the time. None of the more recent studies found compelling evidence that the DQB1 alleles influenced the susceptibility to RA. A few studies suggest that the DQ alleles may influence the clinical or biological expression of the disease, perhaps through a complementary effect of the
DRB1
and DQB1 alleles. DR-DQ complementarity has been demonstrated in the DQ8 transgenic mouse model, although this is not necessarily relevant to the human disease. The role of DPB1 remains hypothetical but may involve an influence of some alleles in relatively mild forms of RA. The DQB1 and DPB1 alleles are in strong linkage disequilibrium with the
DRB1
alleles, making the elucidation of their independent effects a challenging task. Studies are needed to determine whether these linkage disequilibriums can influence the development of autoimmune diseases.
...
PMID:Do the HLA-DQ and DP genes play a role in rheumatoid arthritis? 1123 75
Predisposition to
rheumatoid arthritis
(RA) is thought to be associated with HLA-DR1, -DR4, and -DR10. However, many epidemiological observations are better explained by a model in which the DQ alleles that are linked to these DR alleles, i.e., DQ5, DQ7, and DQ8, predispose to RA, while certain DR alleles have a dominant protective effect. All protective
DRB1
alleles, e.g., *0402, *1301, and *1302, encode a unique motif, (70)DERAA(74). The protection may be explained by the presentation of
DRB1
-derived peptides by DQ to immunoregulatory T cells, because it was demonstrated in various autoimmune disease models that T cell responses to certain self-Ags can be involved in disease suppression. The aim of this study was to analyze whether peptides carrying the DERAA motif are naturally processed by human APC and presented in the context of the RA-predisposing DQ. Using a synthetic peptide carrying the DRB1*0402-derived sequence (65)KDILEDERAAVDTYC(79), we generated DERAA peptide-specific DQ-restricted T cell clones (TCC) from a DQ8 homozygous individual carrying DERAA-negative DR4 alleles. By analyzing the proliferation of these TCC, we demonstrated natural processing and presentation of the DERAA sequence by the APC of all the individuals (n = 12) carrying a DERAA-positive
DRB1
allele and either DQ8 or the DQ8-related DQ7. Using a panel of truncated synthetic peptides, we identified the sequence (67)(I)LEDERAAVD(TY)(78) as the minimal determinant for binding to DQ8 and for recognition by the TCC. These findings support a model in which self-MHC-derived peptide can modulate predisposition to autoimmune disease in humans.
...
PMID:An HLA-DRB1-derived peptide associated with protection against rheumatoid arthritis is naturally processed by human APCs. 1129 Jul 78
Experimental studies in transgenic mice have suggested that HLA-DQ predisposes to
rheumatoid arthritis
(RA), but could also modulate disease severity by presenting peptides derived from self-DR molecules. In particular, a short amino acid sequence, (70)DERAA(74), in the third hypervariable region of HLA-DRB1 confers protection for the disease, while particular HLA-DQ [DQB1*0501/DQA1*01 (DQ5) and DQB1*03/DQA1*03 (DQ3)] molecules predispose to the disease. We have therefore analyzed the allelic distribution of HLA-DRB1, DQA1, and DQB1 and the presence of rheumatoid factor and nodules among 199 German RA patients and 196 healthy controls. Our results show that HLA-DQB1*03/DQA1*03 (or DRB1*04) predisposes to RA more than HLA-DQB1*0501/DQA1*01 (i.e., DRB1*01 and DRB1*10). Homozygosity for DQ3 confers the strongest genetic risk for RA (OR = 19.79 compared to OR = 10.05 for two doses of shared epitope (SE) positive HLA-DRB1 alleles). Furthermore, patients carrying both predisposing DQ and (70)DERAA(74)-positive HLA-DRB1 alleles are more often rheumatoid factor (RF) negative than patients carrying predisposing DQ alleles alone. Only one out of 14 patients (7%) with a protective combination (DQ3/(70)DERAA(74) and DQ5/(70)DERAA(74)) had rheumatoid nodules compared to 67 out of 144 patients (46.5%) with predisposing DQ alleles alone (OR = 0.12, 95% CI: 0.02-0.72, p = 0.004). These results demonstrate a protective role of (70)DERAA(74)-positive
DRB1
alleles against disease severity among RA patients.
...
PMID:Protection against severe disease is conferred by DERAA-bearing HLA-DRB1 alleles among HLA-DQ3 and HLA-DQ5 positive rheumatoid arthritis patients. 1133 77
<< Previous
1
2
3
4
5
6
7
8
9
10
Next >>