Chondrogenic Differentiation of Human Adipose Tissue-Derived Stem Cells in Functional PLGA Scaffolds

Abstract

We evaluated the chondrogenic potential of human adipose tissue-derived stem cells (hADSCs) in a functional PLGA scaffold containing two chondrogenic factors, dexamethasone and transforming growth factor-alpha l. In the functional scaffold group, hADSCs were seeded into functional PLGA scaffolds and cultured with complete medium. In the positive control group, hADSCs were seeded into a conventional PLGA scaffold and cultured with chondrogenic medium. In the negative control group, cells in a conventional PLGA scaffold were cultured with complete medium. After four weeks of differentiation, the expression of cartilage-specific genes and proteins was evaluated by reverse transcriptase polymerase chain reaction (RT-PCR) and western blotting. Alcian blue and Safranin 0 stain were performed to confirm chondrogenic differentiation. Both functional PLGA scaffolds and conventional PLGA scaffolds seeded with hADSCs were also transplanted into the subcutaneous pockets of athymic mice. After four weeks, chondrogenesis was analyzed by RT-PCR and western blotting for collagen type II. Alcian blue stain was also performed. The results of our in vitro study show that a functional PLGA scaffold is as efficient at stimulating chondrogenic differentiation as the positive control. The results of our in vivo study show that chondrogenic differentiation is significantly up-regulated with functional PLGA scaffolds. In conclusion, we show that a functional PLGA scaffold can trigger the chondrogenic differentiation of hADSCs in vitro without chondrogenic factors. Furthermore, we show that chondrogenic differentiation of hADSCs can be maintained in vivo through the in situ release of chondrogenic factors.