title: Five new epitope-defined monoclonal antibodies reactive with GM2 and human glioma and medulloblastoma cell lines.
abstract: In order to investigate GM2 expression in gliomas, the GM2-positive human glioma cell line (HGL) D-54 MG, which contains 0.6 nmol GM2/mg protein, representing 77% of the total monosialoganglioside fraction, was used as an immunogen for the production of anti-GM2 monoclonal antibodies. For ganglioside designations, see IUPAC-IUB (Eur. J. Biochem., 79: 11-21, 1977) and Svennerholm (J. Neurochem., 10: 613-623, 1963). Five IgM monoclonal antibodies (DMAb-1 through DMAb-5) specifically recognizing the GalNAc beta1-4(NeuAc alpha 2-3)Gal-terminal epitope common to GM2 and GalNAC-GD1a are reported. The antibodies did not react with GM1, GM3, GD2, GD3, GD1a, GD1b, and GQ1b. Purified anti-GM2 MAbs were used to define the expression of the "GM2" terminal epitope by cultured human malignant and normal cells by radioimmunoassay and membrane immunofluorescence. Among neuroectodermal tissue-derived cell lines, DMAb-3, at an optimal concentration of 5 micrograms/ml, showed high reactivity (radioimmunoassay binding ratios greater than 20) with 9 of 19 HGLs, 3 of 5 medulloblastoma, 4 of 5 neuroblastoma, and 1 of 3 melanoma lines. Moderate reactivity (binding ratio, 10-20) was exhibited by 3 HGL, 2 medulloblastoma, and 1 neuroblastoma lines and low reactivity (binding ratio, 3-10) by 5 HGL lines; no reactivity was detected with 2 HGL and 2 melanoma lines. Densitometric evaluation of monosialoganglioside extracts from human glioma and medulloblastoma cell lines in conjunction with immunostaining on thin-layer chromatograms showed that GM2 represents the major monosialoganglioside in 8 of 10 HGL and in 3 of 4 Med lines. In these lines the amount of GM2 ranged from less than 0.1 to 0.6 nmol/mg protein. These results indicate that GM2 represents a proportionally increased ganglioside of most glioma, medulloblastoma, and neuroblastoma cells in vitro.
authors: Department of Pathology, Duke University Medical Center, Durham, North Carolina 27710.
authors: F D
authors: FD
authors: Vrionis
authors: C J
authors: CJ
authors: Wikstrand
authors: P
authors: P
authors: Fredman
authors: J E
authors: JE
authors: Månsson
authors: L
authors: L
authors: Svennerholm
authors: D D
authors: DD
authors: Bigner
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology*; D000912:Antibodies, Neoplasm / Q000276:immunology; D000918:Antibody Specificity; D000951:Antigens, Neoplasm / Q000276:immunology*; D004306:Dose-Response Relationship, Immunologic; D000939:Epitopes; D005678:G(M2) Ganglioside / Q000276:immunology*; D005732:Gangliosides / Q000276:immunology*; D005910:Glioma / Q000276:immunology*; D006801:Humans; D008527:Medulloblastoma / Q000276:immunology*; D008545:Melanoma / Q000276:immunology; D009447:Neuroblastoma / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D000912:Antibodies, Neoplasm; D000951:Antigens, Neoplasm; D000939:Epitopes; D005732:Gangliosides; D005678:G(M2) Ganglioside