Influence of bFGF on in vitro expansion and chondrogenic construction of articular cartilage-derived progenitor cells

BACKGROUND: Articular cartilage-derived progenitor cells (ACPCs) possess the properties of both chondrocytes and bone marrow mesenchymal stem cells (BMSCs). However, the number of ACPCs in articular cartilage is low, and an effective culture system is needed for their expansion. Basic fibroblast growth factor (bFGF) promotes the expansion of chondrocytes and BMSCs, as well as the chondrogenic differentiation of BMSCs. Therefore, the aim of this study was to clarify whether bFGF could be used for in vitro expansion of ACPCs and whether bFGF promoted chondrogenic construction of ACPCs. METHODS: We applied the fibronectin adhesion method to sort mice ACPCs and compared the proliferative, osteogenic, and chondrogenic abilities of ACPCs by adding various concentration of bFGF (0, 2, and 5 ng/mL) to the cell culture medium. Then used the best system to construct cartilage with ACPCs in vitro and in vivo. RESULTS: The results indicated that bFGF promoted ACPCs proliferation, inhibited osteogenesis, and promoted chondrogenesis, and that a cell culture system containing 2 ng/mL bFGF was optimal for these effects. ACPCs constructed cartilage using the filtered culture system presented homogeneous cartilaginous histological structure in vitro and in vivo. CONCLUSIONS: By applying this cell culture system, homogenous cartilage tissue was constructed in vitro and in vivo by chondrogenic induction, which provides a stable cell expansion culture method for the application of ACPCs in cartilage repair.