A peptide epitope from the gag protein of SIV and from HIV-1 is descri
bed which is presented by a cynomolgus macaque MHC molecule and with H
LA B14. Comparisons were drawn between recognition of this peptide and
that of a second peptide defined in SIV and HIV-2 which has been repo
rted to be presented by the rhesus macaque molecule MaMuA01 and HLA B5
3 respectively.