FIG. 4.

Effect of late drug treatment on in vitro engineered cartilage formation. Gross view, histology, safranin O staining, and collagen II immunohistochemistry of the in vitro engineered cartilages without or with drug treatment at various drug concentrations started at either 1 week or 2 weeks post-cell seeding. 1 W and 2 W, respectively, represents post-cell seeding times at 1 week and 2 weeks, and 1×, 2×, and 4×, respectively, represent 1 time, 2 times, and 4 times of drug concentrations. Bar=100 μm. The experiment was repeated with 4 tissue samples. Color images available online at www.liebertpub.com/tec