Lymphoproliferative response to the 30-kDa protein and a crude lysate from Salmonella typhimurium in patients with ankylosing spondylitis.

To determine the lymphoproliferative response to the 30-kDa protein (p30) of Salmonella typhimurium in patients with ankylosing spondylitis (AS). Lymphoproliferative response was determined in peripheral blood mononuclear cells (PBMCs) from 30 patients with AS and 40 healthy subjects. Cells were cultured with concanavalin A (Con A), a crude lysate of S. typhimurium (StCL), or p30. Lymphoproliferation was measured by the MTT assay. Our data show that the mitogenic response to Con A was similar in both groups studied; however, the lymphoproliferative response to StCL and p30 was statistically higher in AS patients than in healthy subjects. Our data strongly suggest that S. typhimurium, and particularly p30, are associated with AS.