Diversidade molecular do v??rus da imunodefici??ncia humana tipo 1 no estado da Bahia.

Abstract

A an??lise de sequ??ncias gen??micas ?? uma forma poderosa para se estudar a diversidade do HIV-1 e sua expans??o nas popula????es, al??m de ser crucial para dar suporte ?? vigil??ncia epidemiol??gica e ao desenvolvimento de terapias e vacinas eficazes. Neste estudo foram geradas sequ??ncias dos genes gag e env do HIV-1 de 61 pacientes infectados em Salvador e do pol de 58 pacientes de Feira de Santana, Bahia, Brasil. A bioinform??tica foi utilizada para subtipar, genotipar as muta????es de resist??ncia, determinar a press??o seletiva e predizer o uso de coreceptor. Em Salvador, 92,6% das amostras foram do subtipo B e 7,4% foram recombinantes BF1. Em Feira de Santana, 67,2% foram do subtipo B, 6,9% F1, 1,7% C e 24,1% BF1. Onze (19,0%) destes isolados apresentaram muta????es de resist??ncia. Pacientes infectados pelo B tinham em m??dia 0,4 muta????es de resist??ncia e nenhuma muta????o deste tipo foi observada em BF1. Com base na caracteriza????o da al??a V3 do gene env em 43 amostras de Salvador, foram encontradas 18,2% de variantes brasileiras (B???-GWGR), 46,5% de GPGR e 34,9% de GXGX. O tempo m??dio de diagn??stico positivo foi de 13 anos para o subtipo B' e 9 anos para o subtipo B (GPGR + GXGX). Setenta e seis por cento destes v??rus fazem uso do coreceptor CCR5, enquanto 24% foram classificados como capazes de usar o CXCR4. Encontramos uma associa????o entre o subtipo B??? e um maior tempo em anos de diagn??stico positivo para HIV-1. As preval??ncias de subtipo B' e de recombinante B/F1 em Salvador foram menores do que as encontradas em estudos anteriores na Bahia e no Brasil, por outro lado, em Feira de Santana foi encontrada uma alta preval??ncia de B/F1.Genomic analysis of sequences is a powerful tool to perform studies in HIV-1 diversity and expansion in the populations and it is crucial to give support to epidemiological surveillance, new therapies and vaccines development. In this study, sequences were generated from gag and env genes from 61 HIV-1 infected patients sampled in Salvador and from pol gene in 58 infected patients sampled in Feira de Santana, Bahia, Brazil. Bioinformatic tools were used to subtype, genotype the resistance mutations, determine the selective pressure and to predict coreceptor use. In Salvador, 92.6% of the samples were subtype B and 7.4% were recombinant BF1. In Feira de Santana, 67.2% of the samples were subtype B, 6.9% were F1, 1.7% was C and 24,1% were recombinant BF1. Eleven (19.0%) of these isolates presented resistance mutations. HIV-1 subtype B infected individuals had, in average, 0.4 resistance mutations by sequence and no mutation was observed in BF1. With regard to V3 loop of gene env, it was found 18.2% of Brazilian variants (B'-GWGR), 46.5% of GPGR and 34.9% of GXGX. The env sequences showed through to negative pressure. The time, in average, since the diagnosis was 13 years among subtype B' and 9 years among subtype B isolates. Seventy-six percent of these viruses use the CCR5 coreceptor, while 24% were able to use CXCR4. We have found an association between subtype B??? and a longer period of time since the HIV positive diagnosis. The prevalence of B??? and B/F1 in Salvador were smaller than the found in previous studies in Bahia state and in Brazil, on the other hand, in Feira de Santana it was found a higher prevalence of B/F1