CROSS-REACTIVE HIV-1-SPECIFIC CTL IN RECENT SEROCONVERTERS FROM PUNE,INDIA

In the light of the diversity of HIV, matching the genotype of candida te HIV vaccines with the transmitted genotype may be required. Alterna tively, matching the immunotype of HIV vaccines and transmitted subtyp es may be the best option. Since studies of cross-subtype HIV-1 immuni ty are limited, subtype B specific cytolytic T lymphocyte (CTL) respon ses were measured in subtype C infected individuals. HIV-1 subtype B-s pecific CTLs, plasma viral load and absolute CD4 and CD8 lymphocyte nu mbers were measured in six HIV-1 subtype C infected individuals within a year of seroconversion, HIV-1 subtype B env, gag and nef-specific C TL precursor frequencies were measured by limiting dilution analysis. Three of the six subjects had demonstrable CTL directed at more than o ne HIV-1 subtype B antigens. One individual demonstrated CTL directed against all three HIV-1 subtype B antigens, while two individuals did not demonstrate CTL against HIV-2 subtype B antigens. The frequencies of CTL precursor were not associated with plasma viral load or absolut e CD4 cell counts in peripheral blood. These findings suggest that som e individuals recently infected with subtype C HIV-1 generate cross-re active CTL that are directed against HIV-1 subtype B.