Inability of newt epidermal cells to migrate over concanavalin A-coated substrates

Pieces of coverslip glass coated with various proteins were implanted under one edge of a fresh skin wound on adult newt hind limbs so that the implant served as wound bed for migrating epidermal cells as they attempted to form a wound epithelium. Despite the fact that concanavalin A (Con A) receptors could be demonstrated on newt epidermal cells with fluorescein isothiocyanate (FITC)-conjugated lectin, Con A-coated implants supported practically no migration, an even poorer response than the modest amount of migration that occurred on uncoated glass. Coomassie blue staining verified that the lectin formed a complete film over the glass, and peroxidase binding assays showed that even after several hours in the wound, the Con A binding sites for mannose were still available. Migration on fibrinogen-coated glass (a good migration substrate) was not affected by placing the implants next to Con A-coated implants. Thus, the failure to migrate on Con A cannot be explained by soluble Con A effects from lectin leaching off the implants. These data suggest that linkages between cell surface mannose and the substrate are not part of the strategy by which newt epidermal cells migrate.