INFECTIVITY AND IMMUNOGENICITY OF SIVMAC HIV-1 CHIMERIC VIRUSES (SHIVS) WITH DELETIONS IN 2 OR 3 GENES (VPR, NEF AND VPX)/

Two SHIVs with two or three genes deleted (SHIV-drn and SHIV-dxrn) wer e constructed. The inoculation of monkeys with SHIN-drn resulted in sh ort-term viremia, but inoculation with SHIV-dxrn did not. At 68 weeks post-inoculation, the monkeys were reinoculated with a 100-fold higher dose of each SHIV, but none showed viremia. Killer cell activities ag ainst HIV-1 Env were detected in the SHIV-drn- and SHIV-dxrn-inoculate d monkeys. Cross-reactive killer activity against HIV-1 Gag and SIV ma c Gag was observed in one monkey. Antibodies were not detected in the SHIV-dxrn-inoculated monkeys, but the SHIV-dxrn-inoculated monkeys sho wed an anamnestic antibody reaction. These data indicate that SHIV-drn is infectious to and immune-inducible in macaques but SHIV-dxrn is no t.