Effect of ONO-8815Ly in the early stages of OA (tibia). Histological findings and grade of degeneration, scored using Mankin's system, in (a) medial and (b) lateral tibial condyles at two weeks after the operation. Sections were prepared from samples of (a and f) G-S, (b and g) G-C, (c and h) G-0, (d and i) G-80, and (e and j) G-400, and stained with (a to e) H&E or (f to j) safranin-O. Magnification, 200× (H&E) and 40× (safranin-O). Scale bar, 200 μm (H&E) and 2.0 mm (safranin-O). *P < 0.05. Values are the mean ± standard deviation. OA, osteoarthritis.