Histocompatibility antigens in progressive systemic sclerosis (PSS; scleroderma)

Patients with progressive systemic sclerosis (PSS; scleroderma) were typed for the HLA-A, -B, and -DR antigens. No significant differences in the frequencies of any HLA-A or -B antigen were found. In the subgroup of patients with PSS and diffuse scleroderma (PSS-DS), the frequency of Bw35 was increased (0.30 vs 0.17 in controls;P<0.005, correctedP>0.2). Although patients with PSS-DS also had an increased frequency of DR1 antigen (0.27 vs 0.12 in local controls;P<0.005, correctedP<0.05), no association between Bw35 and DR1 antigens could be detected. We found no increase in the frequencies of the DR3 or DR5 antigens in patients with PSS. However, in a subset of PSS patients with pulmonary fibrosis, an increase in DR3 and a decrease in DR4 antigens (P<0.005) were observed. Serum antibodies to centromere occurred more frequently in DR1-positive than DR1-negative patients (0.46 vs 0.18;P<0.005). This study of a large number of patients with PSS failed to confirm previously reported associations of PSS with the HLA-B8/DR3 haplotype or HLA-DR5 antigen.