Association of HLA-DRw4 with rheumatoid arthritis in black and white patients

Anticollagen antibodies and immune response gene products in rheumatoid arthritis

Circulating antibodies to native and denatured types I and II human and bovine collagens were assayed in patients with rheumatoid arthritis (RA), patients with other rheumatic diseases, and normal individuals. A subgroup of this population was also assayed for reactivity with typing reagents which detect determinants (MT and HLA-DR) present in human immune response gene products. The mean titers of antibodies to each collagen tested were not significantly higher in RA patients when compared with patients who had other rheumatic diseases. Although both MT3 and MT4 were significantly associated with RA, there was no significant association between the anticollagen antibodies and any MT type or HLA-DR4. These studies raise a question concerning the role of collagen antibodies in the pathogenesis of RA and suggest that genes distinct from those coding for HLA-DR may play a role in the expression of the disease.

Specific HLA-DR4-associated histocompatibility molecules characterize patients with seropositive juvenile rheumatoid arthritis

The structural and functional heterogeneity of HLA-DR4-associated specificities was investigated in patients with seropositive juvenile rheumatoid arthritis, a DR4-associated disease. Using a combination of HLA-D analysis by mixed lymphocyte culture and electrophoretic analysis of immunoprecipitated Ia molecules by two-dimensional polyacrylamide gels, we observed a surprisingly homogeneous pattern of HLA-D antigen expression. All patients expressed common structural products of the DR and DS loci, and 7/12 homozygous DR4 patients expressed a rare and subtle HLA-D heterozygous phenotype.

[HLA-A, B, C, and DR typing in rheumatoid polyarthritis]

HLA-A, B, C typing were performed in 72 caucasians with rheumatoid arthritis. HLA-DR typing were accomplished in 40 patients among these 72 subjects. DR4 was clearly increased with a frequency of 55 p. 100 versus 18 p. 100 in controls. We did not find an association between DR4 and the presence of rheumatoid factor. Clinical and biological signs are similar in rheumatoid arthritis with and without DR4. Two other HLA antigens, B40 and Cw3, were increased and their frequency was twice as high in patients as compared with controls. A synthesis of six studies published in the world confirms the elevation of B40 in this disease and later on suggests the elevation of Cw3 which is often linked with B40. The association of rheumatoid arthritis with B40 and Cw3 can be explained by a linkage disequilibrium between DR4 and B40 on the one hand, between DR4 and Cw3 on the other hand.

Extended haplotypes of chromosome 6 in adult rheumatoid arthritis

In 46 patients with rheumatoid arthritis (RA) the allele C4B*3 occurred in 6 patients, while among 350 normal controls, it occurred 6 times (P less than 0.00002). Among 9 white and 1 black families, each of which had 2 or more members with RA, there were 36 haplotypes associated with RA. An extended haplotype (specific HLA-B, DR, complotype haplotypes in significant linkage disequilibrium) containing C4B*3: HLA-B15, DR4, BF*S, C2*C, C4A*3, C4B*3, was found twice (P less than 0.001) among whites with the disease-associated chromosomes.

Strong association of rheumatoid arthritis with the presence of a polymorphic Ia epitope defined by a monoclonal antibody: comparison with the allodeterminant DR4

Among individuals with rheumatoid arthritis the presence of the polymorphic Ia antigen epitope detected by the monoclonal antibody 109d6 is more strongly correlated with disease susceptibility than are other specificities, such as HLA DR4, DRw53 (MT3) or the antigenic determinant, defined by the monoclonal antibody 17-3-3S. The cells of 93% of Caucasian and Hispanic patients react with the 109d6 reagent. As was the case in normal individuals, all DR4-positive patients express the 109d6 determinant; however, 26% of those with rheumatoid arthritis have the epitope recognized by antibody 109d6, but lack the specificity DR4. Of these, one-third expresses only HLA DR1 and DQw1 (MT1, MB1) determinants. Studies of family members reveal that here the determinants 109d6, DR1, and DQw1 are encoded by the same unusual haplotype. In certain other individuals with rheumatoid arthritis who express DR4, DRw53, and the 109d6 determinants, family studies show that the 109d6 epitope is encoded not only by the haplotype specifying DR4 but also by the opposite haplotype that does not bear the genes for DR4. This suggests that homozygosity for certain Ia epitopes is relevant to determining the disease-susceptibility state. These studies emphasize the utility of monoclonal antibodies as reagents for the recognition of Ia epitopes that are more closely involved in the determination of disease susceptibility than are allomorphic molecules detected by conventional typing alloantisera.

HLA DR antigens and gold toxicity

One hundred and thirty-two patients with rheumatoid arthritis treated with gold have been studied for possible associations between HLA DR antigens and different adverse reactions occurring during such therapy. Patients possessing HLA DR3 had a significantly greater frequency of side effects than patients lacking this antigen. It was particularly noticed that DR3 positive patients on gold treatment had an 11 times higher risk of getting proteinuria than those without DR3. The lowest frequency of side effects was seen in DR7 positives. No significant differences between the DR antigen groups with respect to skin eruptions, liver reactions, or leucopenia were evident.

HLA DR antigens in rheumatoid arthritis

The prevalence and possible prognostic significance of HLA-DR antigens have been studied in 129 patients with seropositive (RF-positive) classical rheumatoid arthritis (RA). HLA-DR4 was increased in RA, whilst HLA-DR2 was decreased, though it was not associated with either low titres of RF or with good prognosis. HLA-DR3-positive patients had the highest prevalence of antibodies to nuclear antigens, and the antigen correlated negatively to the presence of subcutaneous nodules, bony erosions and familial RA. RA patients possessing DR3 thus had some of the characteristics of SLE. HLA-DR5 was not present in male RA patients. An absence of familial RA was observed among DRw8-positive patients.

Seronegative rheumatoid arthritis. A distinct immunogenetic disease?

Measurement of serum rheumatoid factor (RF) by conventional methods in patients with rheumatoid arthritis (RA) has repeatedly identified a subpopulation of patients without detectable RF. Previous investigators have consistently confirmed the association of HLA-DR4 with seropositive RA, but studies of seronegative RA have been limited and contradictory. We studied 140 randomly selected patients from Alabama, all of whom had either classic or definite RA, and we were able to complete HLA typing for 110 of these individuals. Eighty were consistently seropositive (on at least 2 separate occasions) and 30 were consistently seronegative (on at least 3 separate determinations). There was no statistically significant difference between the seronegative RA patients and 123 control subjects in the distribution of DR antigens. In seropositive RA, there was a significant increase in DR4 (P less than 0.001; relative risk = 8.02; attributable risk = 49.2%) and a significant decrease in DR3 (P less than 0.001; relative risk = 0.14) and DR7 (0.01 greater than P greater than 0.001; relative risk = 0.33). The clinical data also distinguished between seropositive RA and seronegative RA; subcutaneous nodules (37.5%) and vasculitis (6.3%) were present only in seropositive RA. DR4 positively did not correlate with any of the clinical variables measured in the seropositive RA group. In contrast, DR4 in the seronegative RA group was associated with more destructive disease. The data suggest that seronegative RA represents a disease entity clinically and immunogenetically distinct from seropositive RA. Moreover, our results indicate that DR4 may be a previously undisclosed marker for disease severity in seronegative RA.

DR antigens and rheumatoid arthritis: a study of two populations

Thr prevalence of HLA-DR antigens was determined in a group of white patients with rheumatoid arthritis, similar patients originating from the Indian subcontinent, and corresponding controls. Rheumatoid arthritis was found to be highly associated with DR4 in the white patients but with DR1 in the Indian patients. These results raise the possibility that the DR antigens themselves do not play a part in increasing susceptibility to rheumatoid arthritis, but the locus for increased susceptibility is probably closely linked to the DR locus.