Combination of ascorbate and growth factor (TGF beta-3) in thermo-reversible hydrogel constructs embedded with rabbit chondrocytes for neocartilage formation

This study evaluated the potential of using poly(NiPAAm-co-AAc) as an injectable drug delivery carrier and a cell therapeutic agent in the form of a supporting matrix for the chondrogenic differentiation of rabbit chondrocytes. In particular, rabbit chondrocytes were embedded in hydrogels containing a combination of ascorbate and transforming growth factor beta-3 (TGF beta-3). Hydrogel constructs containing embedded cells either without ascorbate or a combination of ascorbate and TGF beta-3 were used as controls to determine the effects of ascorbate and TGF beta-3 on chondrogenic differentiation. The level of cartilage associated ECM proteins was examined using immunohistochemical staining for collagen type II as well as by Safranin-O and Alcian blue (GAG) staining. The results showed that ascorbate is an important factor for preparing cartilage constructs because of its action on chondrocyte phenotype modulation and proliferation.