Effect of h-2 genes on expression of HLA-b27 and yersinia-induced arthritis

HLA-B*2705 transgenic mice were continuously backcrossed to mice of the BIO background with various haplotypes. A high level of expression of the HLA-B27 protein was detected on peripheral blood lymphocytes (PBLs) from mice homozygous for H-2^b, H-2^f, H-2^s, H-2^p, H-2^r, and H-2^k haplotypes by FACS analysis with the ME-1 antibody. A lower level of expression of B27 was observed on PBLs from H-2^v mice. Little or no expression of B27 was detected on PBLs from H-2^q or H-2^d mice. We hypothesize that the HLA-B27 heavy chain is analogous to and competes with endogenous class I heavy chains in the H-2^d, H-2^q and H-2^v haplotypes. Interestingly, other studies in our laboratory have demonstrated that mice with the H-2^d and H-2^q haplotypes with deletions of certain T cell receptor subsets are more prone to Yersinia-induced arthritis (YIA). Therefore, the mouse model of YIA may provide insights into the mechanisms of HLA-B27-linked spondyloarthropathies in man.