TFM-C inhibits the mast cell activation in CAIA. CAIA was induced in B6 mice and the mice were then treated with 10 μg/g TFM-C, celecoxib or vehicle as described in Figure 2. A. Quantification of degranulated mast cells in synovium of joints 12 days after induction of CAIA. * P < 0.05, compared with vehicle-treated group. * P < 0.05, compared with celecoxib-treated group. Results shown are the mean + SEM of six mice per group and were pooled from two experiments. B. Hisopathologic features of degranulated or intact mast cells in joints of representative vehicle-, celecoxib- and TFM-C- treated mice (toluidine blue stained; original magnification, × 100). White arrows indicate intact mast cells and black arrows indicate degranulated mast cells.