Abstract:
Transmitted/founder virus (T/F) is responsible for the establishment of human immunodeficiency virus type 1 (HIV-1) infection and induces primary anti-HIV-1 immune responses; therefore, it is important to study the viral HIV-1 population in an effort to understand the early phases of HIV-1 infection. We amplified HIV-1 env genes from sera derived from recently infected Thai individuals, and established an envelope of glycoproteins (Env)-recombinant viruses. Generated Env-recombinant viruses were tested for their neutralization susceptibility to neutralizing human monoclonal antibodies (NHMAbs) and entry inhibitors, as well as being subjected to genotypic analysis. Most recombinant viruses were susceptible to neutralization by NHMAbs to Env gp41, whereas approximately one-third of the recombinant viruses were susceptible to a NHMAb against the CD4 binding site of gp120. In addition, all env genes were classified into CRF01_AE genes and showed low genetic divergence. These results provide information for understanding the immunological and genetic characteristics of CRF01_AE Env that were derived from recently infected Thai individuals. Fourteen Env-recombinant viruses were constructed to study phenotypic and genotypic env gene characterizations. There were thirteen R5-tropism, whereas one was X4R5-tropism that were susceptible to neutralization by 4E10, 2F5 and IgG1 b12; they were 100% (14/14), 64% (9/14) and 35% (5/14), respectively. However, all fourteen Envrecombinant viruses were resistant to 2G12. Additionally, the amino acid residues and potential N-linked glycosylation sites on V1/V2 have an inverse significant correlation with IC50 of 4E10, p value 0.012 and 0.029, respectively. In contrast, no correlation was found in IC50 of 2F5 and IgG1 b12. However, T/F viruses were moderately susceptible to IgG1 b12 which is potentially a CD4 binding site which induces the high levels of neutralization susceptibility. Early Env clones show varying neutralization susceptibility to specific viral entry whereas the length of V1/V2 amino acids is negatively significant correlation with TAK- 779 susceptibility of the recombinant viruses, p value 0.048. Early env are classified into CRF01_AE env which show relatively low divergence compared to chronically CRF01_AE Env clones that infected Thai individuals. Finally, this study is the first report on the subtype CRF01_AE T/F Env-recombinant viruses that provide a valuable tool for understanding immunological and antigenic characterizations in early phases of HIV-1 infection.
Mahidol University. Mahidol University Library and Knowledge Center