Reciprocal effects of Schistosoma mansoni infection on spontaneous autoimmune arthritis in IL-1 receptor antagonist-deficient mice.

Schistosome infections have been shown to prevent inflammation in induced-type arthritis models. However, its effects on spontaneous arthritis remain unknown. We here investigated the effects of Schistosoma mansoni (Sm) infection on spontaneous autoimmune arthritis in IL-1 receptor antagonist (IL-1Ra)-deficient mice. Sm infection partially reduced the severity of arthritis in male IL-1Ra-deficient mice. The splenic responses of IL-17 and TNF-α were reduced, while those of IL-4 and IL-10 were enhanced by the infection. However, Sm infection increased IgG rheumatoid factor and anti-dsDNA IgG serum levels. These results suggest that Sm infection has both ameliorating and exacerbating effects on autoimmunity in IL-1Ra-deficient mice.