Human hepatocellular carcinoma-associated changes of glycosphingolipids detected by two monoclonal antibodies FH2 and IB9

The changes of minor glycosphingolipids associated with human hepatocellular carcinomas were studied using monoclonal antibodies. Glycosphingolipids of twelve patients were isolated from the tumor tissues and their adjacent cirrhotic liver tissues. The immunoreactivities of glycosphingolipids with two monoclonal antibodies FH2 and IB9, that define x-structure (Gal beta 1-4[Fuc alpha 1-3]GlcNAc) and sialosyl alpha 2-6galactosyl residue, respectively, were studied by a solid phase enzyme-linked immunosorbent assay and a chromatogram immunobinding assay. X-structure was detected in the upper-phase neutral glycosphingolipids from both the cirrhotic liver tissues and the tumor tissues, but was generally expressed more strongly in the latter tissues. The thin-layer chromatography patterns of x-active glycosphingolipids were more complex in the tumor tissues. Sialosyl alpha 2-6galactosyl residue was detected in two ganglioside fractions. One ganglioside with faster migration on a thin-layer chromatogram was found in both the non-tumorous tissues and the tumor tissues. Another ganglioside with slower migration was more often detected in the tumor tissues. It was concluded that some of minor glycosphingolipids detected by monoclonal antibodies FH2 and IB9 could be the 'tumor-associated' antigens.