The therapeutic effects of basic fibroblast growth factor contained in gelatin hydrogel microspheres on experimental osteoarthritis in the rabbit knee

Objective. To investigate the therapeutic effects of basic fibroblast growth factor (bFGF) contained in gelatin hydrogel microspheres on osteoarthritis (OA) development in rabbit knee joints. Methods. I-125-labeled bFGF contained in gelatin hydrogel microspheres was administered to the knee joints of normal rabbits to confirm the sustained-release kinetics of bFGF in the knee joint. In addition, the expression of proteoglycan core protein messenger RNA was examined using real-time polymerase chain reaction to confirm the anabolic effects on the cartilage treated with the sustained release of bFGF. The bFGF in gelatin hydrogel microspheres was administered to the knee joint once every 3 weeks (a total of twice) from 4 weeks after anterior cruciate ligament transection (ACLT). Ten weeks after ACLT, gross morphologic and histologic examinations were performed. Results. Sustained release of bFGF in the knee joint continued for > 7 days and induced the anabolic effects on the cartilage. Intraarticular injections of bFGF contained in gelatin hydrogel microspheres suppressed the progression of OA in the ACLT rabbit model. Conclusion. Our findings demonstrated that sustained release of bFGF into the joint had therapeutic effects on OA development in a rabbit model. Our results suggest the potential feasibility of a new conservative treatment for OA.