• Citer

An interfacial instability approach to erythrocyte adhesion by macromolecules

par Coakley, William Terence;Gallez, Dominique ;Thomas, N.E.;Baker, Amanda
Référence Colloids and surfaces. B, Biointerfaces, 2, 1-3, page (281-290)
Publication Publié, 1994-03

Article révisé par les pairs

• Détails
• Contenu

Résumé :

Models of cell plasma membrane interactions in the presence of adhesive macromolecules often follow the general principles initially formalised by Derjaguin, Landau, Verwey and Overbeek for colloidal particles in suspension. In this model the parallel membranes of mutually adhering cells are considered to lie in an energy minimum at an equilibrium separation distance which is determined by the relative size and range of attractive and repulsive interactions. In contrast, the interfacial instability model considered here directs attention to the dynamic processes which can result in deformation of a thin aqueous intermembrane film to give localised spatially periodic contact points. The contact seam of erythrocytes suspended in polycation, polysaccharide or lectin solutions has been examined in this work by light and electron microscopies. The seams formed by erythrocytes in solutions of the lectins concanavalin A and wheat germ agglutinin show spatial periodicity of contacts (range 0.8-0.5 μm). In normal cells the polycation-induced seam is always spatially periodic while it is usually continuous and parallel in dextran solutions. In the latter case, pretreatment of the cells by the protease pronase results in spatially periodic contacts on subsequent exposure of the cells to dextran. For both polycation- and polysaccharide-induced contact the experimental changes which increase or decrease membrane attraction consistently lead to a decrease or increase respectively in the lateral contact separation distance (range 3.4-0.8 μm). These changes in lateral contact separation distances are qualitatively consistent with the predictions of interfacial instability theory. The changes are discussed as particular examples of a general consequence of the form of membrane interaction profiles. © 1994.