A mixed co-culture of mesenchymal stem cells and transgenic chondrocytes in alginate hydrogel for cartilage tissue engineering.
Date of Issue2012
School of Chemical and Biomedical Engineering
Cartilage degeneration remains one of the challenging problems for clinicians worldwide due to the avascular nature and limited self-regeneration capacity of the cartilage tissue. In stem cell based therapy, stem cells are reprogrammed into chondrocytic cells under defined induction recipe, which can be implanted to the injured site for regeneration. Synovial mesenchymal stem cells (SMSCs) are considered as a good cell source due to their proliferation capacity and inclination to gain chondrocytic phenotype with proper inducing agents, e.g., transforming growth factor (TGF)-ß3. One of the strategies in stem cell-based therapy for cartilage degeneration is co-culture, whereby chondrocytes release a multitude of substances to induce the differentiation of stem cells into chondrocytic cells. In this study, we adopted the co-culture strategy in cartilage tissue engineering to construct cartilage tissue for regeneration. Chondrocytes were enhanced with recombinant adenoviral vector to deliver the TGF-ß3 gene and mixed with SMSCs for co-culture. Gene expression in both chondrocytes and SMSCs was characterized. Together with other biochemical assays either in vitro or in vivo, the results indicated that the expression of TGF-ß3 in chondrocytes via the adenoviral vector had not only induced SMSC differentiation into chondrocytic cells, but also reversed the chondrocyte dedifferentiation to regain the chondrocyte phenotype. Therefore, this co-culture strategy in conjunction with the TGF-ß3 gene delivery was proved to be a potential therapy for cartilage-related degeneration or trauma.