Application of liposomes to generation of monoclonal antibody to glycosphingolipid: production of monoclonal antibody to GgOse4Cer.

Liposomes were applied to the immunization with GgOse4Cer and screening for production of monoclonal antibody to GgOse4Cer. Four-week-old and 22-week-old Balb/c mice were immunized with GgOse4Cer and Salmonella minnesota R595 lipopolysaccharides incorporated liposomes which were composed of dipalmitoyl-phosphatidylcholine and cholesterol. Since antibody response to GgOse4Cer was higher in 22-week-old than 4-week-old Balb/c mice after immunization, 22-week-old Balb/c mice were used for the immunization prior to generation of the monoclonal antibodies to GgOse4Cer. The screening of monoclonal antibodies was performed by complement-dependent liposome immune lysis assay using GgOse4Cer-containing liposomes. Six kinds of monoclonal antibodies, AG-1, -2, -3, -4, -5, and -6, of the IgM class were established. The specificities of the monoclonal antibodies obtained were defined by complement-dependent liposome immune lysis assay using various glycosphingolipids incorporated in liposomes and by thin-layer chromatography (TLC) with immunostaining. All of the monoclonal antibodies reacted only with GgOse4Cer in the liposome immune lysis assay. In addition, the monoclonal antibodies reacted only with GgOse4Cer in the TLC immunostaining. However, none of the monoclonal antibodies obtained was capable of removing natural killer activity from C3H/He mice spleen cell suspensions in vitro. Liposomes may be useful in the procedures of immunization and screening for generation of antiserum and monoclonal antibody to GSLs.