Porous gelatin-chondroitin-hyaluronate tri-copolymer scaffold containing microspheres loaded with TGF-β1 induces differentiation of mesenchymal stem cells in vivo for enhancing cartilage repair

The aim of the study was to produce a novel porous gelatin-chondroitin-hyaluronate scaffold in combination with a controlled release of transforming growth 0 factor beta 1 (TGF-beta 1), which induced the differentiation of mesenchymal stem cells (MSCs) in vivo for enhancing cartilage repair. Gelatin microspheres loaded with TGF-beta 1 (MSTGF beta 1) showed a fast release at the initial phase (37.4%,), and the ultimate accumulated release,vas 83.1%, by day 18. The autologous NMSCs seeded on MS-TGF beta 1/scaffold were implanted to repair full-thickness cartilage defects in rabbits as in vivo differentiation repair group, while MSCs differentiated in vitro were seeded on scaffold without MS-TGF beta 1 to repair the contra lateral cartilage defects (n = 30). Fifteen additional rabbits without treatment for defects were used as control. Histology observation showed that the in vivo differentiation repair group had better chondrocyte morphology, integration, continuous subchondral bone, and much thicker newly formed cartilage layer when compared to in vilro differentiation repair group 12 and 24 weeks, postoperatively. There was a significant difference in histological grading score between these two experimental groups, and both showed much better repair than that of the control. The present study implied that the novel scaffold with MS-TGF beta 1 might serve as a new way to induce the differentiation of MSCs in vivo to enhance the cartilage repair. (c) 2006 Wiley Periodicals, Inc.