Effect of Membrane Lipid Composition on Mobility of Lymphocyte Surface Immunoglobulins

Abstract

Some types of cellular regulation are known to be associated with changes in membrane fluidity. For example, it has been shown that the neoplastic transformation of cells from a variety of origins is accompanied by a marked increase in cell surface fluidity (Inbar et al., 1973; Shinitzky and Inbar, 1974; Ben-Bassat et al., 1977; Inbar et al., 1977a). Both cell cycle regulation (deLatt et al., 1977) and contact inhibition of cells in vitro (Inbar et al., 1977b) are also known to be linked with membrane fluidity changes. These changes in fluidity have been demonstrated to be a function of the membrane cholesterol/phospholipid (c/p) ratio (Shinitizky and Inbar, 1974; Chen et al., 1975; Borochov and Shinitzky, 1976; Cooper et al., 1978), so that the relatively low ratios are associated with increased fluidity. The c/p ratio in cell membranes can be experimentally manipulated by mixing the cells with liposomes of various cholesterol content (Borochov and Shinitzky, 1976; Cooper et al., 1978; Inbar and Shinitzky, 1974; Alderson and Green, 1975; Dunnick et al., 1976; Chen and Keenan, 1977).