Polymorphism characteristics of HIV-1 gpl20 and 5 hypervariable regions.

BACKGROUND/AIM To investigate polymorphism characteristics of HIV-1 gpl20 and its 5 hypervariable regions. MATERIALS AND METHODS Length polymorphism, potential number of N-linked glycosylation sites (PNGSs), and sequence characteristics of nearly all available global gp120 and its 5 hypervariable regions from HIV-1 subtypes A, B, C, D, G, and H were analyzed. RESULTS We found that the majority of HIV-1 gpl20s have 496-515 amino acids and 21-30 PNGSs, suggesting that a gp120 with this length might be a good virus candidate for vaccine development. Among 5 hypervariable regions, the V3 regions had the lowest levels of length polymorphism and heterogeneity and less PNGSs, while V1 and V4 regions had high levels of length polymorphism and heterogeneity and more PNGSs. These results suggest that reducing the polymorphism, heterogeneity, and PNGSs of the 4 hypervariable regions should be taken into account in AIDS vaccine development for effectively eliciting immune response. Except for subtype D, other subtypes have the consensus V3 sequences with R5 tropism, implying that the majority of HIV-1 strains are R5 strains. CONCLUSION The results suggest that CCR5 antagonists may be extremely efficient for AIDS treatment and R5 strains should be used as candidates for AIDS vaccine development.