Fig. 1
From: CCL17 blockade as a therapy for osteoarthritis pain and disease
Interferon regulatory factor 4 (IRF4) and chemokine (c-c motif) ligand 17 (CCL17), but not TNF, are required for collagenase-induced osteoarthritis (CiOA) pain and optimal disease development. CiOA was induced in wild-type (WT), Tnf−/−, Irf4−/− and Ccl17E/E mice by intra-articular collagenase injection (see “Methods”). a Pain (change in weight distribution; see “Methods”) was monitored over time. b Representative histologic pictures of knee joints (Safranin O/fast green stain, original magnification ×100) and quantification of arthritis at day 42. c Representative histologic pictures of osteophytes (indicated by arrow) (Safranin O/fast green stain; original magnification ×100) and quantification of osteophyte size. Results are expressed as the mean ± SEM; n = 5–10 mice per strain (from two independent experiments). i.a., intra-articular; LT, lateral tibia; LF, lateral femur; MT, medial tibia; MF, medial femur. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001, WT vs. Irf4−/− mice. #p < 0.05, ##p < 0.01, ###p < 0.001, WT vs. Ccl17E/E mice