Electrospun nanofibrous alginate sulfate scaffolds promote mesenchymal stem cells differentiation to chondrocytes

Cartilage tissue engineering is one of the interesting approaches used for repairing cartilage injuries. This study reports the fabrication of polyvinyl alcohol/alginate sulfate (PVA/ALG-S) nanofibrous mats as a functional support for chondrogenic differentiation of human bone marrow mesenchymal stem cells (hBM-MSCs). The PVA/ALG-S nanofibers were obtained through electrospinning of PVA solutions containing 10, 20, and 30 wt% of ALG-S. The appearance of a band at 833 cm(-1)assigned to the symmetrical C-O-S vibration associated to a C-O-SO(3)group confirmed the presence of ALG-S in nanofibrous mat. The SEM images illustrated the bead-free and smooth morphology of PVA/ALG-S nanofibers with a mean diameter of 185 +/- 0.06 nm. The MTT assay of the hBM-MSCs seeded on scaffolds indicated the appropriate cytocompatibility of nanofibrous PVA/ALG-S scaffolds. Furthermore, the appropriate attachment and spreading of the hBM-MSCs based on SEM images, and their differentiation to the chondrocyte-like cells accompanied by a decrease in cell growth on MTT analysis and more color absorption in alician blue staining indicated the effective role of alginate sulfate on cell differentiation. Finally, the expression of Type II collagen by RT-PCR and immunocytochemistry analyses revealed the chondrogenic differentiation of hBM-MSCs on alginate sulfate nanofibers.