HLA-E and the origin of immunogenic self HLA epitopes.

摘要

Sir,In a recent paper from the Terasaki Foundation (Mol. Immunol. 2009, doi:10.1016/j.molimm.2009.10.024), Ravindranath et al. report that mAb MEM-E/02 to non-classical (class Ib) HLA-E molecules widely crossreacts with acid-denatured classical (class la) heavy chains coated on microbeads, particularly with the B40, Cw5, Cw18, B35, Cw7, B13, B41, and B56 alleles. Using a set of competitor peptides, these authors map the MEM-E/02 epitope to the alpha2 domain of class la molecules, and claim the epitope is discontinuous, e.g., it arises due to the spatial proximity of two separate stretches: ~(115)QFAYDGKDY123 (encompassing strands S2 and S3 in the 3-sheet platform of the antigen binding groove, and including a connecting loop pointing toward the associated beta2m subunit) and ~(137)DTAQI~(142) (at the beginning of the alpha2 domain a helix, on the solvent-exposed top of the groove).