Demonstration of Shared Epitopes between Bacterial Proteins and HLA Class-I Proteins Using Monoclonal Antibodies

Abstract
Monoclonal antibodies were used to identify the presence of epitopes on bacterial proteins which are cross-reactive with HLA-B27. Anti-HLA-B27 monoclonals, B27M2 and YE-2 reacted with a major protein of approximately 35 kDa, which was found to be OMPA. On some strains a 19 KDa protein was also seen. Anti-Shigella flexneri monoclonals were also developed which reacted with a 36 kDa protein and a 19 kDa protein. The 36 kDa protein was OMPF. These antibodies also reacted with a synthetic peptide representing amino acids 63-83 of the B*2705 sequence. These results support a potential role for molecular mimicry in the spondyloarthropathies.