Specific glycolipid antigen(s) in SV40-transformed cell membranes

A glycolipid extract was prepared from an SV40-transformed hamster cell line (EH-SV) according to the Folch partition procedure. The glycolipids from the aqueous layer were incorporated in liposomal membranes composed of lecithin/sphingomyelin/cholesterol (1:1:2 by weight). This liposomal preparation was inoculated in Syrian hamsters to raise immune sera. The sera were absorbed with trypsinized "normal" hamster cells (EH-N) and tested on various cell lines by the indirect immunofluorescence technique. When used for staining living cells, the immune serum produced a distinct cell-surface fluorescence with SV40-transformed cell lines regardless of the cell origin (e.g., rat or hamster). No reaction was observed with heterologous Py-transformed cell lines, spontaneously transformed cells, or sera from non-immunized hamsters. When used for staining acetone-fixed cells, the antiglycolipid serum reacted specifically with a thermostable antigen in the nuclear envelope and the cytoplasm of SV40-transformed cells. The sera lack interfering SV40 T reactivity. The results indicate the presence of related SV40-specific glycolipid antigen(s) in the plasma membrane, the nuclear membrane and probably other endomembranes of SV40-transformed cells.