Local anaesthetics increase susceptibility of untransformed cells to agglutination by concanavalin A

CELL agglutination by concanavalin A (con A) is accompanied by redistribution of con A receptors on the cell surface from a random pattern to form patches^1-5. Differences in the susceptibility of untransformed and transformed cells to agglutination by con A may therefore reflect differences in the ability of receptors to move laterally within the membrane to form patches. For example, it has been suggested^6-8 that the higher susceptibility of transformed cells to agglutination by low doses of con A might be associated with a more fluid lipid plasma membrane matrix. Enhanced fluidity of the bilayer matrix would allow greater lateral movement of receptors within the membrane and favour formation of patches of receptors after binding of con A to the cell surface. The increased susceptibility of L cell nutritional auxotrophs to agglutination by con A after enrichment of their membranes with fluid phospholipids⁹ supports this view. We report here that local anaesthetics which increase the fluidity of phospholipids in model membranes also cause a significant increase in the susceptibility of untransformed cells to agglutination by low doses of con A.