title: HLA antigens and rheumatoid arthritis. Association between HLA-DRw4 positivity and IgM rheumatoid factor production.
abstract: Serologic HLA typing was carried out on 33 seropositive and 15 seronegative patients with rheumatoid arthritis (RA). Association with the DRw4 antigen was found only in seropositive RA (61%, compared with 27% in normal controls; P less than 0.05, Fisher's exact test), whereas the antigen had a normal frequency in seronegative RA patients (27%). The serum concentrations of IgM and IgE immunoglobulins were significantly higher in seropositive than in seronegative RA patients (p less than 0.01, Mann-Whitney test), whereas the concentrations of the other immunoglobulin classes and of the complement factors C3 and C4 did not show any significant differences.
mesh_terms: D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000276:immunology*; D003165:Complement System Proteins / Q000096:biosynthesis; D005260:Female; D006680:HLA Antigens / Q000032:analysis*; D006801:Humans; D007075:Immunoglobulin M / Q000276:immunology*; D007136:Immunoglobulins / Q000096:biosynthesis; D008297:Male; D008875:Middle Aged; D012217:Rheumatoid Factor / Q000096:biosynthesis*
chemical_list: D006680:HLA Antigens; D007075:Immunoglobulin M; D007136:Immunoglobulins; D003165:Complement System Proteins; D012217:Rheumatoid Factor