Immunohistochemical profiling of bone-destructive markers in CAIA joints. (A) Wild-type CAIA joints showed threefold higher expression of RANKL at Day 10 of disease than did those from KO CAIA mice. (B) CAIA WT and KO mice expressed C5aR in the infiltration area and in the bone. Properdin-deficient mice with CAIA had lower STAT1 (C) and STAT3 (D) expression in the infiltration area compared with the WT CAIA group. (E) TGF-β expression was decreased in the inflammatory area and the cartilage in properdin-deficient CAIA joints. The findings shown in (A) through (E) are representative of 10 sample sections from five mice/group; magnification ×40. The graphs show the mean ± SD of positive cell numbers (A, for RANKL expression) or intensity expression (B through E), for STAT1, 3 and TGF-β3 expression) calculated after assessment of 10 sections from five mice/group. P values are according to the statistical analyses with Student t test.