Abstract
Abstract: :
Purpose:We have previously demonstrated that the basement membrane of the corneal epithelium possesses a rich nanoscale 3–dimensional surface topography. We have also shown that nanoscale surface features engineered into synthetic matrices modulate cell shape, orientation, adhesion and migration. Here, we report that topographic features of the substratum modulate proliferation in human primary corneal epithelial cells. Methods:X–ray lithography was used to pattern silicon wafers with six 2x2 mm areas with grooves and ridges ranging in pitch (groove width + ridge width) from 400nm to 4µm, as well as control planar silicon. Epithelial cells were harvested from cadaver globes as previously described and 10,000 cells were seeded into wells of a 24 well plate containing the patterned silicon chips. After seeding (day 0), cells were allowed to attach for four hours and counted. The cells were grown at 37°C and 5% CO2 for a period of 5 days. At this time, the cells were fixed with 4% paraformaldehyde/PBS and stained with DAPI. Cell number was determined by counting and proliferation was expressed as percent increase in cell number. Results:At feature sizes greater than 1200 nm, primary human corneal epithelial cells grew at a similar rate compared to cells grown on planar silicon. However, proliferation of primary human corneal epithelial cells was suppressed at feature sizes less than or equal to 1200 nm. Conclusions:Nanoscale topographic features modulate proliferation of corneal epithelial cells. These findings have relevance to the rational design of corneal and other prosthetics, evolving strategies in tissue engineering as well as interpretation of results from in vitro investigations.
Keywords: cornea: epithelium • wound healing • proliferation