Enhancement of cellular immune response in HIV-1 seropositive individuals:A DNA-based trial

A DNA-based vaccine containing HIV-1 Env and Rev genes was tested for safet y and host immune response in 15 HIV-infected asymptomatic patients with CD C positive lymphocyte counts greater than or equal to 500/mu l of blood and receiving no antiviral therapy. Successive groups of patients received thr ee doses of vaccine at 30, 100, or 300 mu g at 10-week intervals in a dose- escalation trial. Some changes were noted in cytotoxic T-lymphocyte activit y against gp160-bearing targets. Importantly, enhanced specific lymphocyte proliferative activity against HIV-1 envelope was observed in multiple pati ents. Three of three patients in the 300-mu g dose group also developed inc reased MIP-1 alpha levels which were detect able in their serum. Interestin gly patients in the lowest dose group showed no overall changes in the immu ne parameters measured. The majority of patients who exhibited increases in any immune parameters were contained within the 300 mu g, which was the hi ghest dose group. These studies support further investigation of this techn ology for the production of antigen-specific immune responses in humans. (C ) 1999 Academic Press.