title: Transfer and co-amplification of a gene encoding a 96-kDa immune IFN-inducible human melanoma-associated antigen. Preferential expression by mouse melanoma host cells.
abstract: An immune IFN-inducible human melanoma-associated glycoprotein Ag, 96-kDa MAA, having preferential distribution on metastases has been defined by mouse mAb CL203.4. To initiate molecular genetic analysis of 96-kDa MAA, the gene encoding the Ag was transfected into mouse B16 melanoma cell clone B78H1. Formation of B78H1-transfectant colonies expressing a surface Ag reactive with mAb CL203.4 in an immunorosetting assay was dependent on addition of chromosomal DNA from human melanoma cells [primary (1 degree) transfer] or from Ag-expressing transfectant cells (2 degrees, 3 degrees, 4 degrees transfer). The mAb CL203.4-reactive species expressed by the transfectant cells is a glycoprotein with a molecular mass 93-kDa, within the range of 93 to 96-kDa observed for the endogenous human Ag. In the presence of tunicamycin, an inhibitor of N-linked glycosylation, both mouse melanoma transfectants and human melanoma cells express a 50- to 51-kDa antigenic species. Human alu family repeat sequences (h-alu) are present in the genomes of 3 degrees transfectant cells. Continued presence of these h-alu after dilution of extraneous human DNA by three cycles of transfection suggests their association with the transferred 96-kDa MAA gene. Use of a selective co-amplification procedure led to transfectant cells' increased expression of 96-kDa MAA and to commensurate increases in their content of presumed 96-kDa MAA gene-associated h-alu. Preferential DNA-mediated transferability of the 96-kDa MAA+ phenotype into B78H1 cells as compared with LMTK- mouse fibroblasts suggests host cell specificity of 96-kDa MAA gene expression.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D000937:Antigen-Antibody Reactions; D000951:Antigens, Neoplasm / Q000235:genetics*; D002460:Cell Line; D005784:Gene Amplification; D005796:Genes; D007150:Immunohistochemistry; D007371:Interferon-gamma / Q000494:pharmacology*; D008545:Melanoma / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D058950:Melanoma-Specific Antigens; D051379:Mice; D008970:Molecular Weight; D009363:Neoplasm Proteins / Q000235:genetics* / Q000276:immunology; D012091:Repetitive Sequences, Nucleic Acid; D014162:Transfection
chemical_list: D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D058950:Melanoma-Specific Antigens; D009363:Neoplasm Proteins; D007371:Interferon-gamma