Correlation of proliferation, morphology and biological responses of fibroblasts on LDPE with different surface wettability

In order to find a correlation between cell adhesion, growth and biological response with different wettability, NIH/3T3 fibroblast cells were cultured on plasma-treated low-density polyethylene (LDPE) film generated with radio frequency. Different surface wettabilities (water contact angle 90–40°) were created by varying the duration of plasma treatment between 0 and 15 s, respectively. Growth and proliferation rate of cells on LDPE surfaces was evaluated by MTT assay, and cell morphology, by means of spreading and adhesion, was characterized by scanning electron microscopy (SEM). The expression of particular genes in cells contacted on films with different wettability was analyzed by RT-PCR. Using the MTT assay, we confirmed that the amount of cell adhesion was higher on surface of film with a water contact angle of 60° than with other water contact angle. Also, the proliferation rate of cells was highest with a water contact angle of 60°. It was confirmed by SEM that the morphology of cells adhered with a water contact angle of 50–60° was more flattened and activated than on other surfaces. Furthermore, c-fos mRNA in cells showed maximum expression on the film with contact angle range of 50–60° and c-myc mRNA expressed highly on the film with a contact angle of 50°. Finally, p53 gene expression increased as wettability increase. These results indicate that a water contact angle of the polymer surfaces of 50–60° was suitable for cell adhesion and growth, as well as biological responses, and the surface properties play an important role for the morphology of adhesion, growth and differentiation of cells.