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Updated: May 28, 2026

Immunopeptidomics: Isolation of Mouse and Human MHC Class I- and II-Associated Peptides for Mass Spectrometry Analysis
Published on: October 15, 2021
Position 45 influences the peptide binding motif of HLA-B*44:08
Soumya Badrinath1, Trevor Huyton, Heike Schumacher
1Institute for Transfusion Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
Abstract:
Position 45 represents a highly polymorphic residue within HLA class I alleles, which contacts the p2 position of bound peptides in 85% of the peptide-HLA structures analyzed, while the neighboring residues 41 and 46 are not involved in peptide binding. To investigate the influence of residue 45 at the functional level, we sequenced peptides eluted from recombinant HLA-B*44:08(41Ala/45Met/46Ala) molecules and compared their features with known peptides from B*44:02(41Thr/45Lys/46Glu). While HLA-B*44:02 has an anchor motif of E at the p2 anchor position, HLA-B*44:08 exhibits Q and L as anchor motif. The 45(Met/Lys) polymorphism contributes to the alteration in the peptide-binding motif and provides further evidence that mismatches at position 45 should be considered as nonpermissive in a transplantation setting.
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