Immunologic response to protein immobilized on the surface of liposomes via covalent azo-bonding.
A new method for immobilizing protein on the surface of liposomes is described. Inclusion of N-(p-aminophenyl) stearylamide in the lipid composition of vesicles resulted in liposomes that could be 'activated' by diazotization with NaNO2/HCl, and subsequently coupled with protein. Using this method 39.7 +/- 7.5 micrograms egg albumin/mumol phospholipid has been coupled to multilamellar vesicles composed of phosphatidylcholine, cholesterol, and N-(p-aminophenyl) stearylamide in a molar ratio of 15:75:1.1. Furthermore, when the immunologic response of mice to egg albumin that was encapsulated in, nonspecifically absorbed, or covalently linked to liposomes was investigated, only the covalent protein-liposome conjugates elicited pronounced and sustained elevations in antibody titers. These results suggest that the immunoadjuvant effects of liposomes can be maximized by covalently linking protein antigens to their surface.
D000418:Albumins / Q000276:immunology; D000818:Animals; D000917:Antibody Formation; D000941:Antigens / Q000276:immunology*; D001391:Azo Compounds; D055598:Chemical Phenomena; D002621:Chemistry; D005260:Female; D008081:Liposomes; D008563:Membrane Lipids; D051379:Mice; D011506:Proteins / Q000276:immunology*; D013229:Stearic Acids
D000418:Albumins; D000941:Antigens; D001391:Azo Compounds; D008081:Liposomes; D008563:Membrane Lipids; D011506:Proteins; D013229:Stearic Acids; C041713:N-(4-aminophenyl)stearylamide