Effect of Fibroblast Growth Factor-2 and Serum on Canine Mesenchymal Stem Cell Chondrogenesis

Damaged articular cartilage has limited healing capacity due to the lack of blood supply. Tissue engineering using the chondrogenic potential of mesenchymal stem cells (MSCs) is a promising approach for cartilage regenerative therapy. Canines are a relevant animal model for cartilage regeneration, as they suffer from spontaneous cartilage injury similar to humans. However, the chondrogenic capacity and optimal conditions for chondrogenesis in canine MSCs have not been documented. In this study, we investigated the effect of preconditioning with fibroblast growth factor-2 (FGF-2) and fetal bovine serum (FBS) in chondrogenic induction medium on canine MSC chondrogenesis. Our results show that treatment with FGF-2 promoted cell proliferation and the expression of SOX2. Biochemical and histological analyses revealed that higher concentrations of FBS decreased chondrogenesis of canine MSCs expanded without FGF-2. However, cells expanded with FGF-2 showed substantial chondrogenic potential and produced abundant cartilage matrix, even on FBS addition. Quantitative polymerase chain reaction showed that chondrogenic genes were highly expressed in spheroids, when cells were expanded with FGF-2 under serum-free conditions. Thus, the combination of FGF-2 preconditioning and serum-free chondrogenic induction medium enabled efficient chondrogenic differentiation of canine MSCs and contributed to cartilage regeneration research.