EXTRACELLULAR-MATRIX CONSTITUENTS AFFECT SUPERFICIAL GASTRIC EPITHELIAL-CELL ADHESION

The interfoveolar and upper gastric pit cells become necrotic and slou gh off after superficial luminal injury to the gastric mucosa. The sub sequent rapid epithelial restitution of the wound is dependent on an i ntact basal lamina upon which viable mucous cells migrate. Several lin es of evidence suggest that migrating mucous cells recognize specific moieties in the basal lamina which would then affect restitution and t he ability of the gastric mucosa to be repaired. Therefore, this study examined the effect of three individual protein constituents of the e xtracellular matrix, laminin, fibronectin and type IV collagen as well as a synthetic basal lamina, Matrigel, on adherence of mucous cells i solated from guinea-pig stomach to these substrates in culture. After 3 h, approximately 40% of the cells adhered to Matrigel, 25% ts both c ollagen IV and fibronectin, but only about 10% to laminin and 3% to un coated plastic substrates. Disruption of protein synthesis by pre-incu bation with cyclohexamide significantly reduced adherence to Matrigel and collagen IV but not laminin, fibronectin or plastic substrates. Th ese results suggest that gastric mucous cells have multiple receptors for extracellular matrix proteins (ligands) which influence the adhere nce and probably the migration of these cells. Furthermore, some of th ese receptors are synthesized in response to moieties in the substrate itself.