HSP90B2P and immune system disorder: Since then, sporadic reports on findings of autoantibodies in this disease have been described, such as antibodies to retinal antigen(s), heat shock protein (HSP) of some strains of Streptococcus sanguis cross-reactive with human HSP polypeptide [3], antibodies to endothelial cell antigens (AECA) and antibodies to α-tropomyosin [4,5], attesting to the complicated humoral immune disorders in this disease.