Histopathological assessment. The histopathological analysis was performed on formalin-fixed arthritic hind paws by Bolder BioPATH Inc. (Boulder, CO, USA). (a) Individual histological scores of ankle joints on a scale of 0 to 5 for inflammation, bone resorption, pannus formation, and cartilage damage with a maximal histology score of 20 per foot. (b) Representative photomicrographs (16x) of the ankle closest to the (c) mean summed histological score. (d) Dorsal to ventral paw thickness for each group. Notably, the arthritic control animal showed very severe inflammation (S), bone resorption (arrowhead) with mild pannus (small arrow), and cartilage damage (large arrow). *P < 0.05 when compared with the arthritic control group. MTX, methotrexate.
Lu et al. Arthritis Research & Therapy 2011 13:R56 doi:10.1186/ar3304