In vitro adhesion of human dermal fibroblasts on iron cross-linked alginate films

We evaluated the potential of alginate film incorporating ferric ions as a gelling agent (Fe-alginate) in comparison with that incorporating calcium ions (Ca-alginate) as a scaffold for culturing normal human dermal fibroblasts (NHDF). NHDF adhered to Fe-alginate and proliferated well, but no growth of the cells was observed on Ca-alginate. Since vitronectin and fibronectin play pivotal roles in cellular adhesion, their participation in NHDF behavior on alginate surfaces was investigated. We found that vitronectin was a critical element for initial attachment and spreading of NHDF on Fe-alginate. The surface properties of both alginate films were characterized in terms of protein adsorption ability and surface wettability, and it was revealed that Fe-alginate film adsorbed a significantly higher amount of proteins, including vitronectin and fibronectin, and had a higher surface hydrophobicity than Ca-alginate film. Moreover, under serum-free conditions, only a small number of NHDF were able to attach to the surface of Fe-alginate. Fe-alginate appeared to provide an appropriate surface for cellular attachment by adsorption of serum proteins such as vitronectin. These results suggest that Fe-alginate can serve as a scaffold for human fibroblasts and may be useful for tissue engineering research and other biomedical applications.