ENVELOPE PROTEIN AND P18(IIIB) PEPTIDE RECOGNIZED BY CYTOTOXIC T-LYMPHOCYTES FROM HUMANS IMMUNIZED WITH HUMAN-IMMUNODEFICIENCY-VIRUS ENVELOPE

Cytotoxic T cells are the main antigen-specific effector cells of the cellular immune system and MHC class I restricted cytotoxic T-lymphocy te (CTL) responses in mice, acting against the HIV-1 envelope protein, are known to be predominantly directed against an amino acid sequence in the third hypervariable domain. We have investigated the epitope s pecificity of anti-HIV-1 CTL in healthy human volunteers inoculated wi th a recombinant vaccinia expressing the HIV-1 gp160 envelope gene. Th eir isolated lymphocytes were stimulated in vitro with autologous HIV- 1 infected cells. Our results show that immunization with recombinant virus is able to generate virus-specific CTLs to the HIV-1 gp160 envel ope protein and to a 15-residue synthetic peptide corresponding to a h ighly variable region of the envelope p18(IIIB). The CTL response was restricted by class I MHC molecules HLA-A2 and A3 that commonly occur in the human population.