Induction of tenogenic differentiation in human adipose stem cells by manipulating culture medium supplements

The limited ability of tendon to self-repair and the limitation of treatment regimes have hastened the motivation to develop cell-based strategies for tendon repair. Growth factors (GFs) such as EGF, FGF, PDGF and TGF-b participate in tendon formation, ECM synthesis or healing, and may assist tenogenic differentiation. Thus, this work aims to establish culturing conditions that induce tenogenic differentiation of human adipose stem cells (hASCs) using these GFs. Materials&Methods: hASCs were isolated and expanded in a-MEM basic medium. Both freshly isolated and cryopreserved hASCs (P3) were further cultured with different supplements namely basic medium with glutamine (2 mM) and ascorbic acid (0.2 mM) plus i) EGF (10 ng/ ml), ii) FGF (10 ng/ml), iii) PDGF (10 ng/ml) or iv) TGF-b (10 ng/ ml) for 7, 14, 21 or 28 days. hASCs differentiation into tenocytes was assessed by real time PCR analysis of the expression of collagen type I and type III, decorin, and scleraxis. Results: In i) and ii) media, hASCs showed a tenocyte-like aligned distribution after 14 days, while in iii) and iv) it was only observed by 21 days. Overall, hASCs showed a higher gene expression in media i) and ii)