Augmented IL-1β in the IL-10KO mice following antigen-induced arthritis (AIA). (A) Expression of inflammatory cytokines; Il6, Tnf and Il1b were examined in the synovial mRNA of WT (closed circles) and IL-10KO (open circles) mice 3 and 28 days after AIA induction and made relative to the values for 18S ribosomal RNA (n = 4-7, *P <0.05). (B) Representative immunohistochemistry (left) and computer-quantified scoring (right) of IL-1β staining in joint sections (scale bar: 100 μm) for WT and IL-10KO joints. Results show individual joints taken over the course of disease in AIA-challenged mice (n = 3-6). (C) Representative immunohistochemical staining for areas of focal IL-1β secretion in IL-10KO bone 28 days post AIA (scale bar: 300 μm). (D) Il18 and Il33 were examined in synovial mRNA from WT and IL-10KO mice taken three days after AIA induction. Values were made relative to 18S ribosomal RNA (n = 5-11, ***P <0.001). IL-10KO, interleukin-10-deficient; WT, wild-type.