HLA-B27 misfolding: a solution to the spondyloarthropathy conundrum?

Compelling evidence indicates that HLA-B27 is directly involved in the etio pathogenesis of the spondyloarthropathies (SpAs). Several hypotheses based on its native antigenic structure, the peptides it presents and mimicry wit h bacterial epitopes, have been proposed. However, these potential mechanis ms remain largely unsupported by human studies and transgenic animal models . Recent work demonstrating that HLA-B27 misfolds offers a novel alternativ e hypothesis. Here, we review this new information on the folding and assem bly of HLA-B27, and discuss consequences of misfolding that could be releva nt to the pathogenesis of SpAs.