Immunochemical studies of lipids. IV. Reactions of anti-sulfatide antibodies with sulfatide in liposomal and myelin membranes.

Antibodies against sulfatide (3-sulfogalactopyranosylceramide) were raised in rabbits by an intradermal injection of a mixture of sulfatide and bovine serum albumin in Freund's complete adjuvant followed by three to five booster injections in complete adjuvant. Complement fixation assays done with liposomes containing lecithin-cholesterol-hapten (1 : 0.75:0.1, by mol) demonstrated the reactivity of the antibodies with sulfatide, but not with galactosylceramide. The antibody activity was found entirely in the IgM fraction after Sephadex G-200 gel filtration. Anti-sulfatide antibodies were purified with liposomes as the immunoadsorbent. Sulfatide in artificial and natural membranes could react with these antibodies to cause complement-dependent release of a fluorogenic marker from liposomes and resealed myelin membrane vesicles.