Characterization of the gp120 of Circulating HIV Type 1 in a Group of Infected Chinese Blood/Plasma Donors with Asymptomatic and Symptomatic Stages of the Disease

The C2–V5 regions of the HIV envelope gene were cloned and sequenced from DNA samples of four asymptomatic and five AIDS patients from a cohort of HIV-1-infected Chinese plasma and blood donors. Sequence analysis revealed that regardless of the stage of disease, all the patient’s HIV-1 belonged to either clade B′ or circulating recombinant form 15 (CRF15) subtype. However, since these blood donors were infected at a time when circulating CRF15 was not known in that region, it is likely these HIV-1 types belong to clade B′. However, the C2–V5 sequences from AIDS patients clustered differently in the phylogenetic tree than those present in asymptomatic patients and showed a significantly higher divergence and lower diversity compared to those from asymptomatic patients. In addition, more syncytia-inducing viral genotypes were present in AIDS patients than in asymptomatic patients. These results contribute to a better understanding of the pathogenesis of circulating HIV-1 in infected Chinese plasma and blood donors, warrant additional investigation of the possible presence of CRF15 in Chinese blood donors, and may have important implications in the future design of therapeutic strategies for treating these infected patients.