Modulation of adhesive properties of DEAE-dextran with laminin

Abstract

Human squamous epithelial cells produce lower amounts of laminin and fibronectin when cultured on DEAE-dextran than when cultured on gelatin-coated polystyrene ( Biotechnol. Bioeng. , 33:1235). The epithelial cells also spread much more slowly on DEAE-dextran than they do on gelatincoated polystyrene. To determine if the low level of matrix production by cells grown on DEAE-dextran contributed to the slowness of cell spreading on this substrate, microcarriers made from DEAE-dextran were treated with exogenous laminin (10 Μg/cm 2 of surface area) and then examined for ability to support cell adhesion. Squamous epithelial cells spread as rapidly on the laminin-treated DEAE-dextran as they did on gelatin-coated polystyrene (much more rapidly than on untreated DEAE-dextran). This indicates (1) that laminin can bind to DEAE-dextran in a fashion that is biologically usable by anchorage-dependent cells, and (2) that when laminin is bound to DEAE-dextran, the failure of squamous epithelial cells to rapidly spread is overcome. These data support the hypothesis that failure of the cells to synthesize an intact extracellular matrix on DEAE-dextran is responsible, at least in part, for the slowness with which cells spread on this substrate. © 1995 John Wiley & Sons, Inc.