Antibody-mediated targeting of Liposomes to erythocytes in whole blood

Abstract

F(ab)2 fragments derived from anti-rat erythocyte antibody or normal rabbit serum lgG were covalently attached to the surface of liposomes of equimolar amounts egg phoshatidylcholine and cholesterol. These liposomes were interacted with rat, monkey or mouse blood, and their binding to both red and white blood cells was determined. Results of these studies show that coupling of lopsomes to anti-rat erythocyte F(ab)2 considerably enhanched their binding to erythocyte in rat blood. However, no such increase in the binding was observed with rat leukocytes or monkey and mouse erythrocytes. Besides, the interaction between the liposomes and target cells did not affect the permeability properties of the liposome bilayer. these observations indicate that liposomes coupled to cell-specific antibodies may serve as highly useful carriers for homing of drugs/enzymes to specific cells in biophase.