Stimulation of human cytotoxic T cells with HIV-1-derived peptides presented by recombinant HLA-A2 peptide complexes

HLA-A2 heavy chain and beta 2-microglobulin were expressed in Escherichiacoli, and refolded in the presence of peptides derived from HIV-1 RT andgag proteins. When recombinant HLA-A2 molecules were attached to cellslacking HLA-A2, the cells became susceptible to lysis by HLA-A2-restrictedcytotoxic T lymphocyte (CTL) clones specific for peptides derived from RTand gag proteins. Limiting dilution analyses of peripheral bloodmononuclear cells from HIV-1-infected individuals showed that therecombinant HLA-A2 peptide complexes covalently immobilized on microspheresstimulated the development of HLA-A2 peptide-specific CTL. PreformedHLA-peptide complexes may provide an alternative to immunization proceduresthat depend upon intracellular processing of antigen to elicit T cellresponses.