Effect of honeycomb film on protein adsorption, cell adhesion and proliferation

This article describes novel methods for controlling of cell adhesion by using micro porous polymer films. Recently we found the highly ordered micro porous films were formed when poly(ɛ-caprolactone) (PCL) solution was cast on substrates at high atmospheric humidity. The micro porous film has regular honeycomb morphology with a size of 5 μm per cell (honeycomb film). Endothelial cells grew rapidly on the honeycomb film. After 24 h cell culture, the cell number on honeycomb films was lager than that on PCL flat films. In order to elucidate the effect of honeycomb films as a scaffold for cell culture, the adsorbed proteins on honeycomb films under cell culture condition were observed. After conditioning of the honeycomb film and the flat film in DMEM containing 10% foetal bovine serum (FBS) for 72 h at 37 °C in 5% CO2 atmosphere, the adsorbed fibronectin-FITC and albumin-Texasred on the honeycomb films was observed by using confocal laser scanning microscope (CLSM). The observation revealed that fibronectin showed site-selective adsorption behavior on the honeycomb film. Albumin adsorbed on the honeycomb film non site-selectively, while fibronectin mainly adsorbed on inside of honeycomb pores. On the flat film, fibronectin was hardly observed. Since the honeycomb film accelerate the adsorption of fibronectin which is a typical protein as a cell adhesion molecule, the film could be a scaffold with excellent cell adhesion properties.