Heterogeneity of the ARV-2 strain and natural isolates of the human immunodeficiency virus.

To study heterogeneity of HIV isolates ARV-2 and strains isolated from lymphocytes of asymptomatic carriers were cloned using limiting dilutions of virus and infected CEM cells. All viral stocks turned out to be biologically heterogeneous giving clones with cytotoxic and noncytotoxic type of infection. Coinfection of CEM cells with cytotoxic and noncytotoxic variants resulted in interference of their biological effects. This interference ended with distinct cytotoxicity. No correlation between the production of virus and the amount of HIV DNA was found pointing out that nonfunctional DNA copies exist.