HLA class I epitopes: A and B loci.

After our initial report on the HLA class I epitopes, we continue to demonstrate the power of the HLA recombinant single antigens in identifying the specificities of mouse monoclonal antibodies and alloantibodies that were absorbed to and eluted from single HLA antigens expressed by recombinant HLA single antigen cell lines (rHLA cell lines). We have expanded the list of HLA class I epitopes to 94, including the 58 reported earlier. Groups of as many as 58 HLA antigens can apparently share a single epitope. All positive antigens, identified by a mAb or an eluted alloantibody, shared unique amino acids (aa) at one to four positions on the alpha chain of the HLA antigen. The shared aa's were considered a distinguishing characteristic of the epitope.