Liposomes in immunology: multilamellar phosphatidylcholine liposomes as a simple, biodegradable and harmless adjuvant without any immunogenic activity of its own.

Multilamellar phosphatidylcholine liposomes were coated with the antigens human serum albumin (HSA) or bovine gamma globulin (BGG) simply by suspending the liposomes in a solution of the antigens. Antigen coated phosphatidylcholine liposomes showed nearly the same adjuvant activity after intravenous injection as liposomes of a more complex phospholipid composition. Since phosphatidylcholine liposomes are biodegradable, harmless, easily obtainable, have no immunogenic activity of their own and may be administered intravenously, they seem to be a promising immunoadjuvant.