Study On Drug Resistance And Subtype Of HIV - 1 Infected Infant In Some Parts Of China

Background and objectiveHIV is spreading from high risk population to the common, with sexual contact becoming the main way of transmission. Preventing Mother-to-child transmission is suffering the big challenges in China. In developed countries of European and American, they used the highly active antiretroviral treatment （HARRT） to preventing MTCT, controlled at less than2%.The HAART decreased the MTCT rate,but companying the risk of drug resistance.In retrospective study of New York City in1998-1999and2001-2002, the drug resistance was12.1%and19%, respectively. There was no study about HIV-1infected drug resistance in China. In this study, we will test the genotyping drag resistance and HIV-1gene types and analyze the characteristic of V3loop in env gene. Methods1. Using in-house method to test genotyping drug resistance;2. Using Nested PCR to amplify HIV-1env gene and combing with pol gene, to genotype and analyze the Characteristic of V3loop in env gene.Results1. In100DBS of HIV-1DNA tested Positive infants （65infants）,57infants amplified successfully in pol gene. The resistance rates are NNRTIs mutations account for15.79%（9/57）; NRTIs mutations account for8.77%（5/57）; No major mutations appeared in PIs. 2. In100DBS of HIV-1DNA tested Positive infants （65infants）,45infants amplified successfully in pol and env gene.The subtypes including:20.00%CRF₀1AE（9/45）,73.33%CRF_BC（33/45）,4.44%B’（2/45）,2.22%G（1/45）.3. In100DBS of HIV-1DNA tested Positive infants （65infants）,63DBS amplified successfully （48infants）.The characteristic of top V3loop in63DBS samples of env gene shows five types:GPGQ, GPGR, GPGS, GLGR, and GQGR. GPGQ accounted for90.48%（57/63）,1.59%GPGR （1/63）;3.17%GPGS （2/63）1.59%GLGR（1/63）;3.17%GQGR（2/63%）.4. In all63samples of amplified env gene, we predict that87.30%（55/63） samples may use CCR5as co-receptor,4.76%（3/63） samples may use CXCR4as co-receptor,7.94%（5/63） samples can’t predict. In3samples of B’ subtype, they all use CXCR4as co-receptor; In CRF_BC subtype,42samples use CCR5and3unknown; In CRF₀1AE subtype,11samples use CCR5and2unknown; all2samples of G subtype use CCR5co-receptor.Conclusions1. There are drug resistance has been appeared in infants of China. According this founding, the pregnant women should test genotyping drug resistance before they accept antivirus therapy.2. The main virus subtypes of HIV-1infected infants are CRF_BC and CRF₀1AE subtypes in parts of China.3. The amino acid of V3loop in HIV-1env gene shows diverse distribution, containing five types. In CRF_BC and CRF₀1AE subtypes, the main type is GPGQ. This information is important for research and development of HIV-1diagnose reagent and immunology.4. In infants’samples, it predicts that HIV-1enters CD4cell use the CCR5co-receptor, indicating CCR5antagonist can be used in following treatment.