Stimulation of epithelial tissue migration by certain porous topographies is independent of fluid flux

A surface with columnar pores 0.1 or 0.4 mum in diameter is shown to have a novel effect on the migration of corneal epithelial tissue sheets; migrati on is stimulated in a nondirectional manner with respect to migration over a planar, nonporous surface (Dalton, Evans, McFarland, and Steele, J Biomed Mater Res 1999;45:384-394; Steele, Johnson, McLean, Beumer, and Griesser, J Biomed Mater Res 2000;50: 475-482). By blind-ending the pores, we show th at this increase in tissue migration is not dependent on fluid flux through the pores and so appears to occur as a result of surface topography. From transmission electron micrographs, the migrating tissue appears to form eit her close contacts or focal adhesions at the edge of some pore channels; we speculate that this may provide a fulcrum for the enhanced migration. Scan ning electron micrographs suggest that within tissue that migrates over the surfaces that contain blind-ended pores, the cells are more extensively sp read than those in tissue migrating on a planar surface. The migration of d isaggregated epithelial cells is enhanced on surfaces that contain 0.1- or 0.4-mum-diameter pores (compared with a planar surface), and this is simila rly independent of fluid flux. (C) 2001 John Wiley & Sons, Inc.