title: An IgM-producing tumor with biochemical characteristics of a small B lymphocyte.
abstract: A lymphocytic tumor, 38C-13, induced by the chemical carcinogen 7, 12-dimethylbenz(a)anthracene in C3H/eB mice and adapted to tissue culture, produces 7-8 S IgM with "core" carbohydrates (N-acetylglucosamines, mannoses), but not "branch" carbohydrates (neuraminic acids, fucoses, galactoses) attached to the mu heavy, but not to the light chains. Turnover of the 7-8 S 38C-13 IgM is slow (half disappearance time = 10-15 h). The IgM is released from the cells as 7-8 S IgM. The ratio of IgM synthesis to the synthesis of all cellular glycoproteins is 0.005-0.01. After comparison of these data with data obtained with normal B lymphocytes before and after mitogenic stimulation, we conclude that 38C-13 tumor cells are transformed counterparts very near or within the population of small, mitogen-sensitive, resting B lymphocytes.
mesh_terms: D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D055598:Chemical Phenomena; D002621:Chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D007075:Immunoglobulin M / Q000096:biosynthesis* / Q000378:metabolism; D007930:Leucine / Q000378:metabolism; D008358:Mannose / Q000378:metabolism; D051379:Mice; D009374:Neoplasms, Experimental / Q000032:analysis / Q000276:immunology* / Q000378:metabolism; D010455:Peptides
chemical_list: D007075:Immunoglobulin M; D010455:Peptides; D015127:9,10-Dimethyl-1,2-benzanthracene; D007930:Leucine; D008358:Mannose