It is known that mutant mice of the beta-1,3-N-acetylglucosaminyltransferase gene (beta3Gn-T5) respond well to T-cell dependent and independent
antigens. Here, we examined the effectiveness of anti-
ganglioside antibody generation by immunization of
beta3Gn-T5 mutant mice with
liposome-embedded
glycosphingolipids such as GD1a and GT1b. Consequently, the mutant mice showed a more efficient generation of anti-GD1a or anti-GT1b
antibodies than wild-type mice in an
enzyme-linked
immunosorbent assay using sera during immunization. Thus, the
beta3Gn-T5 deficient mutant mice proved more responsive than wild-type mice to not only
protein antigens, but also to
carbohydrates in
glycolipids. Furthermore, about 50% of
monoclonal antibodies generated using splenocytes of the immunized mutant mice were of the
IgG class. Besides general high responsiveness to
proteins and
glycolipids, it could be expected that the mutant mice of
beta3Gn-T5 would be useful in the generation of
monoclonal antibodies towards lacto-/neolacto-series
glycolipids, since these mutants lack lacto-/neolacto-series
glycolipids. In fact, they showed a good serum response in immuno-fluorescence assay with cultured living cells when immunized by
glycolipids extracted from
ovarian cancer cell lines. These results suggested that
beta3Gn-T5 mutant mice are useful for the generation of anti-
glycolipid antigens with lacto-/neolacto-core structures expressed in
cancer cells.