THE HLA-A-ASTERISK-0207 PEPTIDE BINDING REPERTOIRE IS LIMITED TO A SUBSET OF THE A-ASTERISK-0201 REPERTOIRE

Quantitative A0207 peptide binding assays have been developed utilizi ng HLA transfected cells and affinity purified molecules. By using a p anel of single substitution analog peptides, it was demonstrated that A0207 binds peptides with main anchor specificity at position 2 and t he C-terminus similar to A0201. Previous data indicating that A*0207 (bur not A0201) also requires the presence of D or P in position 3 of its peptide ligands was confirmed by the analysis of additional singl e substituted analogs. Finally, by analyzing the A0201 and A*0207 bin ding capacities of panels of unrelated synthetic peptides, it was foun d that 8/15 (53.3%) A0201 binders with D or P in position 3 bound A*0 207, while only 5/72 (6.9%) A0201 binders without D or P in position 3 also bound A0207, Together, these data indicate that although A*020 7 may be included amongst A2 supertype alleles, its peptide binding re pertoire is largely limited to a subset of that bound by A0201. (C) A merican Society for Histocompatibility and Immunogenetics, 1997. Publi shed by Elsevier Science Inc.