The peptide length specificity of some HLA class I alleles is very broad and includes peptides of up to 25 amino acids in length

Abstract

The major ligands presented by MHC class I molecules after natural antigen processing are peptides of eight to ten residues in length, and it is widely accepted that the binding preferences of MHC class I molecules play a dominant role in dictating this classic feature of antigen presentation. In this report, we have reassessed the peptide size specificity of class I human leukocyte antigens (HLAs). By lengthening previously defined T cell epitopes by central amino acid insertion, we demonstrate that the peptide length specificity of some common HLA class I alleles (HLA-B*3501, B*0702 and A*2402) is very broad, and includes peptides of up to 25 residues. These data suggest that the length li..