Cytokine production by lymph node and spleen cells. (A) IL-2 production by Concanavalin-A (Con A)-stimulated inguinal lymph node (LN) cells. (B) IL-2 production by collagen type II (CII)-stimulated spleen cells. (C) IL-17 production by CII-stimulated spleen cells. (D) IFNγ production by CII-stimulated spleen cells. Mice were immunized at day 0 and challenged at day 21. Atorvastatin (A) or pravastatin (P) were given daily, either before (day -28 until day 20) or after (day 22 until day 42) collagen-induced arthritis induction. Mice were euthanized at day 42. Control mice (C) did not receive statins. In negative mice (N), arthritis was not induced and these mice did not receive statins. Inguinal LNs were excised and LN cells were cultured in the presence of Con A for 24 hours. Spleens were excised and spleen cells were cultured in the presence of CII for 72 hours. Cytokine content was measured in the supernatants. n = 12. *Significantly different (P < 0.05) from N; +significantly different (P < 0.05) from C. n = 12 per group. The effect of arthritis induction was assessed using an independent-samples t test; the effect of statin treatments was assessed using one-way analysis of variance, followed by the Bonferroni post hoc test.