title: Alkaline phosphatase in hematopoietic tumor cell lines of the mouse: high activity in cells of the B lymphoid lineage.
abstract: Alkaline phosphatase (EC 3.1.3.1) was assayed in a large number of cultured mouse tumor cell line using p-nitrophenylphosphate as the substrate. Of 19 lines of the B lymphoid lineage, including Abelson pre-B, B lymphoma, and plasma cell tumor lines, all but 1 had substantial activity averaging 407 nmol/min/mg protein (with a range from 5 to 900). Nine T lymphoid and 9 nonlymphoid hematopoietic lines examined had low activity of 0.7 to 4.2 nmol/min/mg protein. The enzyme was markedly enriched in plasma membrane preparations from the B lymphoid cells, but not in those from most T lymphoma cells. The activity of another plasma-membrane-bound enzyme, gamma-glutamyl transferase, did not vary systematically with the type of cell line but was exceptionally high in 1 T lymphoma line. Investigation of pH dependence and susceptibility to inhibition by L-phenylalanine and L-homoarginine indicated similarity of the alkaline phosphatase from B cell lines to the enzyme recoverable from normal mouse kidney, placenta, bone marrow, and lymphoid organs. The enzyme seems to provide a useful marker for tumor lines of the B lymphoid lineage and for their plasma membranes.
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism*; D000818:Animals; D001402:B-Lymphocytes / Q000201:enzymology*; D002460:Cell Line; D002462:Cell Membrane / Q000201:enzymology; D005260:Female; D006412:Hematopoietic Stem Cells / Q000201:enzymology*; D006709:Homoarginine / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D007668:Kidney / Q000201:enzymology; D051379:Mice; D009374:Neoplasms, Experimental / Q000201:enzymology*; D010649:Phenylalanine / Q000494:pharmacology; D010920:Placenta / Q000201:enzymology; D011247:Pregnancy
chemical_list: D006709:Homoarginine; D010649:Phenylalanine; D000469:Alkaline Phosphatase