Search

Cytomegalovirus retinochoroiditis (CMV-R) is the primary cause of blindness among AIDS patients. Since HLA-G is associated with the modulation of the immune response, we hypothesized that variability at the 3' untraslated region (3'UTR) of the gene could be implicated on the predisposition to CMV-R. We evaluated whether HLA-G 3'UTR influences CMV-R development in Brazilian AIDS patients. Peripheral blood DNA was obtained from two groups of patients: (1) AIDS exhibiting CMV-R (n = 40) and (2) AIDS without CMV-R (n = 147). HLA-G 3'UTR typing was performed using sequencing analysis. Allele, genotype and haplotype frequencies were evaluated using Fisher's exact test accompanied by the calculation of the odds ratio and its 95% confidence interval (95% CI). The etiologic (EF) and preventive fractions were also estimated. Compared to AIDS patients without CMV-R, AIDS patients with CMV-R showed increased frequencies of the: (1) + 3001T allele, (2) the + 3001C/T genotype and (3) the UTR-17 (InsTTCCGTGACG) haplotype (EFs = 0.02-0.04). The UTR-3 (DelTCCGCGACG) haplotype was associated with protection against CMV-R development. Although the risk for developing CMR-V at the population level was relatively low (EF), the identification of HLA-G 3'UTR variation sites may help to further evaluate the role of post-transcriptional factors that may contribute to the existent immunosuppresion caused by HIV per se.

Purpose: Since cytomegalovirus retinitis (CR) is an important cause of visual impairment among AIDS patients and HLA-C alleles have been associated with AIDS disease outcome, we typed HLA-C locus in patients with AIDS exhibiting or not CR., Methods: Three groups of individuals were studied: (i) 49 patients with AIDS and CR (Group I), (ii) 161 patients with AIDS without CR (Group II), and (iii) 202 healthy HIV-negative individuals (Group III). HLA-C typing was performed using commercial kits., Results: The HLA-C∗ 07 allele group was underrepresented in AIDS patients with CR ( P =0.005) when compared to controls or when compared to AIDS patients without CR ( P =0.006). The HLA-C∗ 05 allele group was overrepresented in Group II in comparison to Group III ( P =0.017). The frequency of the HLA-C∗ 16 allele group was increased in Group III in comparison to Group II ( P =0.004)., Conclusion: The HLA-C∗ 07 allele group conferred protection against the development of CR in Brazilian AIDS patients, whereas the HLA-C∗ 05 and HLA-C∗ 16 allele groups were associated with AIDS susceptibility or protection, respectively.