FIG. 5.

Effect of mitomycin C treatment on chondrogenic differentiation of MSCs. (A) MSCs in monolayer or at days 1, 7, 10, 14, 21, and 28 of chondrogenic differentiation were treated with 10 μg/mL mitomycin C for 2 h to induce irreversible growth arrest and chondrogenic culture was continued up to day 42. Untreated control pellets (insets) were harvested at the time of mitomycin C treatment in order to assess the degree of differentiation before growth arrest by collagen type II immunohistochemistry. (B) Semiquantitative evaluation of the relative collagen type II–negative area of mitomycin C–treated pellets (day 42) compared with the day 42 untreated control pellets set as 0% blocking (full differentiation). Color images available online at www.liebertonline.com/scd