Second update of the International Registry of HLA Epitopes. I. The HLA-ABC Epitope Database

The International Registry of HLA Epitopes (http://www.epregistry.com.br) is a website-based resource for HLA epitopes important in transplant rejection and platelet transfusion refractoriness. Its primary goal is to document epitopes that are verified experimentally with specific antibodies. Such epitopes can be defined by single eplets and by eplets paired with certain polymorphic residues within a 15-A radius, the dimension of the corresponding structural epitope. This report is an update of the HLA-ABC repertoire including descriptions of 72 antibody-verifications of epitopes defined by eplets and/or eplet pairs. The newly updated version 2.0 EpRegistry shows also the polymorphic residue compositions of structural epitopes corresponding to eplets shared between groups of alleles. At present, 151 eplets have not been antibody-verified, and we ranked them with a so-called ElliPro score as a potential predictor of immunogenicity. Sixty eplets with low ElliPro scores might be considered non-epitopes incapable of inducing specific antibodies.