Conserved MHC class I peptide binding motif between humans and rhesus macaques

Since the onset of the HIV pandemic, the use of nonhuman primate models of infection has increasingly become important. An excellent model to study HIV infection and immunological responses, in particular cell-mediated immune responses, is SIV infection of rhesus macaques, CTL epitopes have been mapped using SIV-infected rhesus macaques, but, to date, a peptide binding moth has been described for only one rhesus class I MHC molecule, Mamu-A*01. Herein, we have established peptide-live cell binding assays for four rhesus MNC class I molecules: Mamu-A*11, -B*03, -B*04, and -B*17. Using such assays, peptide binding motifs have been established for all four of these rhesus MHC class I molecules. With respect to the nature and spacing of crucial anchor positions, the motifs defined for Mamu-B*04 and -B*17 present unique features not previously observed for other primate species, The motifs identified for Mamu-A*11 and -B*03 are very similar to the peptide binding moths previously described for human HLA-B*44 and -B*27, respectively, Accordingly, naturally processed peptides derived from HLA-B*44 and HLA-B*27 specifically hind Mamu-A*11 and Mamu-B*03, respectively, indicating that conserved MHC class I binding capabilities exist between rhesus macaques and humans. The definition of four rhesus MHC class I-specific moths expands our ability to accurately detect and quantitate immune responses to MHC class I-restricted epitopes in rhesus macaques and to rationally design peptide epitope-based model vaccine constructs destined for use in nonhuman primates.