Production of monoclonal antibodies directed to Hanganutziu-Deicher active gangliosides, N-glycolylneuraminic acid-containing gangliosides

We have established three kinds of monoclonal antibodies against gangliosides containing N-glycolylneuraminic acid (NeuGc) by immunization of BALB/c mice with the purified gangliosides inserted into liposomes comprising Salmonella minnesota R595 lipopolysaccharides, and fusion of spleen cells with a mouse myeloma cell line. One monoclonal antibody, SHS-1, which was generated by immunizing mice with purified i-active ganglioside(NeuGc), reacted specifically with the i-active ganglioside(NeuGc) used as an immunogen. Structurally related gangliosides, such as GM3(NeuGc), sialosylparagloboside (SPG) (NeuGc), or I-active ganglioside(NeuGc), corresponding gangliosides [GM3 containing N-acetylneuraminic acid (NeuAc), SPG(NeuAc), i-active ganglioside(NeuAc), and I-active ganglioside(NeuAc)], other gangliosides, or neutral glycosphingolipid (GSL) were not recognized by the monoclonal antibody. These findings indicate that the SHS-1 monoclonal antibody may be specific for NeuGc-containing i-active ganglioside. On the other hand, the other two monoclonal antibodies, MSG-1 and SPS-20, which were generated by immunizing mice with purified ganglioside GM3(NeuGc) and SPG(NeuGc), respectively, showed cross-reactivity to structurally related gangliosides. The MSG-1 monoclonal antibody exhibited reactivity to ganglioside GM3(NeuAc). The SPS-20 monoclonal antibody also cross-reacted with SPG(NeuAc), i-active ganglioside(NeuGc), and i-active ganglioside(NeuAc). Neither MSG-1 nor SPS-20 reacted with corresponding gangliosides, other gangliosides, or neutral GSLs tested. Using the SHS-1 antibody specific for i-active ganglioside(NeuGc), we studied the expression of NeuGc-containing antigen in human colon cancer tissue. An NeuGc-containing glycoconjugate was detected in the colon cancer tissue.