[Behçet's disease and streptococcal antigens]

Many studies have been carried out concerning microbial infections and the occurrence of Behçet's disease. Recently, attention has been focused on the streptococci. The serum antibody titer and delayed type hypersensitivity of patients with Behçet's disease against streptococcal antigens were significantly higher than those of controls. We also found that the oral flora of patients with Behçet's disease was dominated by Streptococcus sanguis, whose serotypes were different from controls. Recent studies have revealed that some streptococcal antigens are associated with heat shock protein and that human gamma delta T cell lines recognize streptococcal antigens. These results suggest that an autoimmune response might be implicated in the etiology of Behçet's disease. To make clear autoimmune mechanisms of Behçet's disease, we have analysed immunogenic antigens of S. sanguis.