Hla Antigens And Susceptibility To Systemic Lupus Erythematosus In Brazilian Patients

Objective: The aim of this study was to investigate association between systemic lupus erythematosus (SLE) and HLA antigens in Caucasoid Brazilian population. Methods: The HLA-A, B, DR and DQ antigens typing was performed using microlymphocytotoxicity test. Fifty-six unrelated Brazilian Caucasoid patients with SLE were studied. Control population for HLA A and B antigen frequency consisted of one hundred-fifty nine unrelated healthy Brazilian Caucasoid and for HLA DR and DQ one hundred-forty one. SLE patients were divided in two groups: 1) with nephritis and 2) without renal involvement. Results: The frequency of HLA-B8 was significantly increased in SLE patients than in controls (25.4% vs 6.9%). HLA-DR2 was significantly increased in SLE patients than was in controls (41% vs 19.1%, RR = 2.95; p < 0.005). When SLE nephritis patients were compared to controls, the frequency of HLA-DR2 (44% vs 19.1%) and HLA-DR3 (32% vs 14.2%) were significantly increased. On the other hand, the frequency of HLA-DR2 was increased in the group of SLE patients without renal disease when compared with control group (37.5% vs 19.1%). Conclusion: Our data suggested that HLA-B8 and HLA-DR2 might have a role in the susceptibility to SLE and HLA-DR3 may be associated with nephritis in Caucasoid Brazilian population with SLE.38633233

Distribution of HLA-DRB1 alleles in a mixed population with insulin-dependent diabetes mellitus from the Southeast of Brazil

HLA class II genes are strongly associated with susceptibility and resistance to insulin-dependent diabetes mellitus (IDDM). The present study reports the HLA-DRB1 genotyping of 41 IDDM patients and 99 healthy subjects from the Southeast of Brazil (Campinas region). Both groups consisted of an ethnic mixture of Caucasian, African Negro and Amerindian origin. HLA-DRB1*03 and *04 alleles were found at significantly higher frequencies among IDDM patients compared to the controls (DRB1*03: 48.8% vs 18.2%, P&lt;0.005, RR = 4.27; DRB1*04: 43.9% vs 15.1%, P&lt;0.008, RR = 4.37) and were associated with a susceptibility to the disease. DRB1*03/*04 heterozygosity conferred a strong IDDM risk (RR = 5.44). In contrast, the HLA-DRB1*11 allele frequency was lower among IDDM patients (7.3% vs 26.3% in controls), but the difference was not significant. These data agree with those described for other populations and allow genetic characterization of IDDM in Brazi