Molecular cloning of two west African HIV2 isolates that replicate well in macrophages

Abstract HIV2 strains were isolated from a Gambian with neuro-AIDS (HIV2 D194 ) and from an asymptomatic Ghanian (HIV2 D205 ). Like HIV1 biological subtype c, both isolates grew slowly and induced few or no syncytia, but eventually produced high levels of particle-associated reverse transcriptase (RT) in cultures of fresh peripheral blood lymphocytes. Each produced even higher levels of RT in fresh human macrophages, especially HIV2 D194 , where maximal RT values of 1,800,000 cpm/ml supernatant of approximately 30,000 cells were measured. The viruses were molecularly cloned after a single passage in culture. Restriction-site analysis showed heterogeneity within each isolate. Nucleotide sequence analysis of HIV2 D194 revealed that, genetically, it is a member of the prototypic HIV2 family, displaying 12% divergence vs. HIV2 ROD and HIV2 NIHZ . In contrast, HIV2 D205 is the most highly divergent HIV2 strain yet described: it is equidistant in relation between the known HIV2 strains and the SIV MAC isolates (23–24 % nucleotide sequence divergence).