Novel fucolipids accumulating in human adenocarcinoma. III. A hybridoma antibody (FH6) defining a human cancer-associated difucoganglioside (VI3NeuAcV3III3Fuc2nLc6).

A new fucoganglioside, 6B, which accumulates in human colonic adenocarcinoma but is absent in normal colonic mucosa, was isolated from a monosialoganglioside fraction of colonic adenocarcinomas. The structure of this ganglioside was identified as shown below by methylation analysis, direct probe mass spectrometry, and enzymatic degradation followed by examination of the degradation products with specific monoclonal antibodies. (formula; see text) The hybridoma (FH6) secreting a monoclonal IgM antibody directed to this glycolipid was selected by reactivity of the antibody with this ganglioside and lack of reactivity with other glycolipids having a closely related structure, such as sialosyllactoneotetraosylceramide (IV3NeuAcnLc4), sialosyllactofucopentaosy(III)ceramide (IV3NeuAcIII3FucnLc4), sialosyllactofucopentaosy(II)ceramide (sialosyl-Lea glycolipid; IV3NeuAcIII4FucLc4), and 6C fucoganglioside (sialosyl 2 leads to 6 fucoganglioside; VI6NeuAcIII3FucnLc6). The antibody was highly reactive with a large variety of human cancer cells, but was less reactive or did not react with a variety of normal cells.