Fabrication of gelatin-micropatterned surface and its effect on osteogenic differentiation of hMSCs.

Studies of the effect of surface chemistries on cell functions on a single surface with different surface chemistry areas have been achieved by micropatterning technology. In this study, a gelatin-micropatterned surface was prepared and used for direct comparison of the effect of different surface chemistries on the osteogenic differentiation of stem cells under the same culture environment. The micropattern was prepared by UV-irradiating photo-reactive azidobenzoyl-derived gelatin-coated surface on a polystyrene plate through a photomask with 200 μm-width stripes. Human bone marrow-derived mesenchymal stem cells (hMSCs) were cultured on the gelatin-modified or micropatterned surfaces in osteogenic differentiation induction medium. Alkaline phosphatase (ALP) staining, alizarin red S staining and real-time PCR analysis were performed to detect the effect of surface chemistry on the osteogenic differentiation of hMSCs. The cells on both the polystyrene area and the gelatin-micropatterned area showed positive ALP staining. Alizarin red S staining results showed that the gelatin-micropatterned area promoted the deposition of minerals. Real-time PCR results indicated that the gelatin-modified surface promoted the expression of osteogenic specific genes encoding ALP and bone sialoprotein. The results suggested the promotive effect of gelatin on the osteogenic differentiation of hMSCs.