Fig. 1.

Identification of an unconventional HLA-B*51:01 subpeptidome that has neither proline nor alanine at position 2. Peptides bound to HLA-B*51 were eluted from HLA-B*51 complexes, purified from HeLa.ABC-KO.B51 cells using the W6/32 antibody. Length and mass of peptides identified are shown in (A) and (B) respectively. Amino acid usage of HLA-B*51 peptidome at position 2 is shown in (C) and (D). Two independent experiments are shown. The predominant residues (>2%) at P2 of non-Pro/Ala2 peptides were labeled using up arrow. Broken horizontal lines indicate 2% of total peptides in each group.