Histological analysis of the hindpaws. (a) Representative haematoxylin and eosin stained section from a control mouse shows normal cartilage and absence of infiltrate in the synovium. (b) Section from mouse with collagen-induced arthritis (CIA) indicates marked infiltration of leukocytes along with disruption and loss of articular cartilage. (c) Section from THR0921 treated CIA mouse showing nearly intact articular cartilage and subchondral bone, and less synovial hyperplasia. (d) Mean ± standard error of the mean of histological scores (n = 10/group; asterisks indicate p < 0.001).