A combinatorial variation in surface chemistry and pore size of three-dimensional porous poly(ε-caprolactone) scaffolds modulates the behaviors of mesenchymal stem cells.

Biomaterial properties play significant roles in controlling cellular behaviors. The objective of the present study was to investigate how pore size and surface chemistry of three-dimensional (3D) porous scaffolds regulate the fate of mesenchymal stem cells (MSCs) in vitro in combination. First, on poly(ε-caprolactone) (PCL) films, the hydrolytic treatment was found to stimulate the adhesion, spreading and proliferation of human MSCs (hMSCs) in comparison with pristine films, while the aminolysis showed mixed effects. Then, 3D porous PCL scaffolds with varying pore sizes (100-200μm, 200-300μm and 300-450μm) were fabricated and subjected to either hydrolysis or aminolysis. It was found that a pore size of 200-300μm with hydrolysis in 3D scaffolds was the most favorable condition for growth of hMSCs. Importantly, while a pore size of 200-300μm with hydrolysis for 1h supported the best osteogenic differentiation of hMSCs, the chondrogenic differentiation was greatest in scaffolds with a pore size of 300-450μm and treated with aminolysis for 1h. Taken together, these results suggest that surface chemistry and pore size of 3D porous scaffolds may potentially have a synergistic impact on the behaviors of MSCs.