Evidence of hydrophobic interaction in adhesion to tissue

Abstract

Reaggregation and agglutination of cells in vitro have served extensively as model systems in the evaluation of various adhesion phenomena that occur in vivo. Such studies have revealed factors that influence cell aggregation^1–3, but the mechanism involved at the molecular level has not been investigated fully. In the agglutination of trypsin-treated and virus-transformed cells by concanavalin A, intercellular cross-linking of receptors by the plant lectin is believed to be necessary after ionic repulsion^4,5. The adhesion of cells may not, however, depend exclusively on the formation of cross links⁶. Hydrophobic inieraction is known to be involved in the aggregation of cell surface components⁷, in the solution behaviour of proteins⁸ and in adsorption⁹, but its contribution to adhesion involving a biological surface has not been considered. This is chiefly because of the difficulty of demonstrating experimentally, by conventional techniques, that hydrophobic interaction can indeed contribute to any significant extent and result in adhesion. I describe here the use of a reactive polyurethane prepolymer to evaluate the conditions required for adhesion to the surface of connective tissue due to hydrophobic interaction.