Chondrogenesis of Human Mesenchymal Stem Cells by Local Transforming Growth Factor-Beta Delivery in a Biphasic Resorbable Carrier

Little is known about the potential of growth factor-augmented biphasic implants composed of a gel and a solid scaffold to enhance chondrogenesis of mesenchymal stem cells (MSCs). We analyzed whether a collagen type I/III carrier and fibrin glue (FG) combined to a biphasic construct support in vitro chondrogenesis of MSCs and allow for local release of bioactive transforming growth factor-beta1 (TGF-β1). Further, a possible advantage of partial autologous fibrin glue (PAF) over commercial FG was assessed. Collagen carriers seeded with 5 × 105 human MSCs with or without FG, PAF, or TGF-β1–upgraded FG were cultured for 6 weeks in chondrogenic medium with or without TGF-β1. Pellets with or without FG/PAF served as controls. FG and collagen carriers allowed strong upregulation of COL2A1, AGC, and COL10A1 mRNA, deposition of collagen-type II, and mediated a significantly higher proteoglycan content compared with biomaterial-free pellets. Collagen-carrier groups contained significantly more proteoglycan than FG...