Histologic images (alcian blue stain) of repair tissue and normal, adjacent cartilage (magnification, 10 × ). (A) Three-week placebo (repair), (B) 3-week TP-508 (repair), (C) 6-week placebo (repair), (D) 6-week TP-508 (repair), (E) 3-week placebo (normal/adjacent), (F) 3-week TP-508 (normal/adjacent), (G) 6-week placebo (normal/adjacent), and (H) 6-week TP-508 (normal/adjacent). At 3 weeks, defect fill was barely observed for both placebo and TP-508, and evidence of PLGA was present in the mesh-like structure under the articular surface. At the 6-week time point, hyaline-like repair tissue was present in the TP-508 group, but the placebo group repair tissue was more similar to fibrocartilage. Color images available online at www.liebertonline.com/ten.