Fig. 4

Adenoviral overexpression of Prok2 in joint tissues exacerbates post-traumatic OA cartilage destruction and hindpaw mechanical allodynia in mice. A, B Mice were IA injected with 1 × 10⁹ pfu of Ad-C (control), Ad-Prok2 (Ad-P), or Ad-HIF-2α (Ad-H) once a week for 3 weeks (n=10 mice per group). OARSI grade and osteophyte maturity were determined at 9 weeks after the first IA injection (A). Representative safranin-O staining images of joint sections at 6 weeks and 9 weeks after the first IA injection (B). C, D Sham- or DMM-operated mice were IA injected with 1 × 10⁹ pfu of Ad-C (control) or Ad-Prok2 (Ad-P) once a week for 3 weeks (n=13 mice per group). OARSI grade and osteophyte maturity were determined at 6 weeks after surgery (C). Representative safranin-O staining images of joint sections at 6 weeks after surgery (D). E von Frey assays were performed at the indicated weeks after DMM operation (n=22 mice per group). Data for OARSI grade and osteophyte maturity are presented as median ± interquartile range (IQR) and paw withdrawal threshold is presented as mean with s.e.m. Significance was evaluated by Kruskal-Wallis with post hoc Bonferroni (A), Mann-Whitney U test (B), and Student’s t test (E), respectively. Scale bar: 50μm