Figure 3.

SOXC gene inactivation protects against tumor necrosis factor (TNF)–induced joint degeneration in mice. A, Schematic representation of the timeline of the experiment. Tamoxifen was injected at 3–4 weeks of age, and doxycycline (dox) treatment began at 5 weeks of age. B and C, Safranin O/fast green (B) and hematoxylin and eosin (H&E) (C) staining of sections from the distal interphalangeal joint of forepaw digit III. The boxed areas in the left panels (original magnification × 2.5) indicate the areas that are shown at higher magnification (original magnification × 20) in the middle and right panels. Arrowhead shows loss of Safranin O–stained cartilage‐specific proteoglycans. Arrows indicate invasion the joint cavity by synovial tissue. Asterisk indicates synovial hyperplasia. D, Fold change in the intensity of Safranin O staining in articular cartilage. E, Fold change in the size of the synovial pannus. Cartilage staining intensity and synovial pannus size were measured in 3 sections per mouse (30 μm apart), using ImageJ software. In D and E, symbols represent individual mice (n = 5 per group); bars show the mean ± SD. See Figure 2 for other definitions.