Genetic characterization of HIV-1 viruses among antiretroviral therapy failure individuals in Suzhou City, China

Abstract Background: This retrospective study was aimed to characterize the distribution of HIV-1 genotypes and prevalence of drug-resistance mutations in antiretroviral therapy (ART) failure individuals in Suzhou City, China. Methods: Polgene of HIV-1 viruses in EDTA anticoagulant plasma samples of 398 ART failure HIV-infected individuals were successfully amplified by using an in-house assay. Drug resistance mutations were analyzed by using the Stanford HIV Drug Resistance Database system (https://hivdb.stanford.edu/hivdb/by-mutations/). HIV-1 genotypes were determined by REGA HIV subtyping tool (version 3.46, https://www.genomedetective.com/app/typingtool/hiv). Near full-length genomes (NFLG) of HIV-1 viruses were obtained by next generation sequencing method. Results: Sequences analysis of the pol gene revealed that CRF 01_AE (57.29%, 228/398) was the dominant subtype circulating in Suzhou City, followed by CRF 07_BC (17.34%, 69/398), subtype B (7.54%, 30/398), CRF 08_BC (6.53%, 26/398), CRF 67_01B (3.02%, 12/398) and CRF55_01B (2.51%, 10/398). The overall prevalence of drug-resistant mutations in ART failure HIV-infected individuals was 64.57% (257/398), including 45.48% (181/398) for nucleotide reverse transcriptase inhibitors (NRTIs) mutations, 63.32% (252/398) for non-nucleoside reverse transcriptase inhibitors (NNRTIs) mutations, and 3.02% (12/398) for protease inhibitors (PIs) mutations. Ten near full-length genomes (NFLG) of HIV-1 viruses were identified, including six recombinants of CRF 01_AE and subtype B, two recombinants of CRF 01_AE, subtype B and subtype C sequences, one recombinant of CRF 01_AE and subtype C and one recombinant of CRF 01_AE, subtype A1 and subtype C. Conclusions: The high prevalence of drug-resistant HIV-1 viruses was a serious challenge for HIV prevention and HIV-infected individuals’ treatment. Therapeutic regimens of ART failure HIV-infected individuals should be adjusted in time according to drug resistance test results. NFLG sequencing facilitates the identification of new HIV-1 recombinant strains.