Epidermal growth factor stimulates integrin-mediated cell migration of cultured human corneal epithelial cells on fibronectin and arginine-glycine- aspartic acid peptide

Purpose. The aim of this work was to show epidermal growth factor (EGF)- dependent migration of human corneal epithelial cells to fibronectin and GRGDSP peptide. The authors assessed the role of cell surface integrin heterodimer α5/β1 in mediating haptotactic cell migration to fibronectin by the use of specific function-blocking integrin antibodies. Methods. A haptotactic cell migration assay in a Boyden chamber was used to compare the relative migration of the cultured human corneal epithelial cells in the presence of fibronectin and GRGDSP peptide-coated filters. Epithelial cells were incubated in the presence of function-blocking integrin antibodies or anti-EGF-receptor antibodies to determine their role in haptotactic cell migration. Results. Human corneal epithelial cells grown as primary cultures migrated in the presence of fibronectin or GRGDSP peptide, but only on stimulation with EGF. Antibodies to the EGF receptor blocked the EGF-mediated stimulation of haptotactic cell migration. Anti-β1 and anti-α5 antibodies each inhibited haptotactic cell migration to fibronectin and GRGDSP peptide. Conclusions. Epidermal growth factor provides an important stimulus of haptotactic cell migration of human corneal epithelial cells. Stimulation of cell migration by EGF was maximal in the range of 5 to 10 ng/nd; this response was completely blocked by incubation with an anti-EGF receptor antibody. Function-blocking integrin antibodies, specifically anti-β1 and anti-α5, inhibited integrin-mediated cell migration to fibronectin and GRGDSP peptide. These data suggest that EGF represents an essential initial stimulus for haptotactic cell migration of human corneal epithelial cells; furthermore, integrins are important in mediating cell migration to fibronectin and GRGDSP.