Characterization of human immunodeficiency virus (HIV1C) variants in peripheral blood mononuclear cells and spermatozoa

Abstract

The presence of distinct viral variants in different cells and secretions of the same person influences the transmission of HIV as well as the response to the host defense and to therapy. Sperm-associated virus is also a risk factor for sexual transmission of HIV. Characterization of the C2-V3 region of HIV1C env gene by the Heteroduplex Mobility Assay (HMA) and sequencing demonstrated the presence of distinct variants in the peripheral blood mononuclear cells (PBMCs) and the sperm of the same individual (n = 6). The translated amino acid sequences of HIV variants in the PBMCs of all the study participants (n = 12) and spermatozoa of the six participants characterized showed the presence of distinct variants with different numbers of N-linked glycosylation (NLG) sites. Infectivity of PBMCs of these persons by co-culture with PBMCs from healthy individuals as detected by the p24 levels in the culture supernatant did not show a correlation with the blood plasma viral load. Interestingly, the infectivity of the sperm samples from four of the five individuals showed positive correlation with the viral load in seminal plasma. The study suggests the presence of distinct viral variants in the sperm and PBMCs of the same person with differential infectivity, and the NLG sites may be associated with the affinity of HIV to receptor/co-receptor usages as well as affinity toward neutralizing antibodies which may influence the risk of sperm associated virus in sexual transmission of HIV and transmit the virus further to distal cells.