Sequence analysis of C2-V4 of HIV-1 env genes in Fuxin / 预防医学

ABSTRACT

Objective@#To learn the sequence characteristics of C2-V4 of HIV-1 env genes and the epitope variation of representative broadly monoclonal neutralizing antibody in Fuxin, so as to provide evidence for the HIV-1 variation trend and the biological characteristics of V3 loop.@*Methods @#The whole blood samples of 112 HIV-1 cases in Fuxin Health Service Center from 2018 to 2019 were collected and the DNA was extracted. The C2-V4 of env genes were amplified by nested-PCR and the PCR products were subjected to sequencing. The bioinformatics analysis was carried out using MEGA software, and the V3-tip motifs, co-receptors, net charge and characteristic amino acids were analyzed using HIV Database. @*Results@#Totally 101 effective gene sequences were obtained, and 5 types of V3-tip motifs were found. Among them, 77 pieces of GPGQ ( 76.24% ) were found in CRF01_AE, CRF07_BC, CRF65_cpx and G subtypes; 19 pieces of GPGR ( 18.81% ) were found in CRF01_AE, CRF07_BC and B subtypes; 3 pieces of GPGH, 1 piece of GPGK and 1 piece of GPGA were only found in CRF01_ AE subtype. The co-receptor was mainly CCR5 ( 84, 83.17% ) . The net charge numbers of V3 loops in CRF01_ AE, CRF07_ BC, B, CRF65_cpx and G were 3.28±1.17, 3.22±0.92, 4.25±0.83, 2.50±0.50 and 3, respectively. The mutation rates of neutralizing antibodies binding b12 and VRC01 were 0-9.90%. The deletion rates of N-glycosylation sites of 295 and 332 were 18.81% and 14.85%, without the loss of both sites.@*Conclusions @#The HIV-1 strains in Fuxin from 2018 to 2019 are macrophage-tropic and non-syncytium-inducing, with GPGQ as the main type of V3-tip motif, CCR5 as the main co-receptor, slow replication and low ability to escape neutralizing antibodies.