title: Myeloperoxidases of human myeloid leukemia cells HL-60 grown in culture and in nude mice.
abstract: Human myeloid leukemia HL-60 cells were grown either in suspension culture or in nude mice. The two types of myeloperoxidase, the small and the large type, in crude extracts of these cells were analyzed by sucrose density gradient centrifugation. The proportions of the small and the large myeloperoxidase varied markedly depending on the growth conditions of cells. In cells in culture, the small myeloperoxidase amounted to 80% of the total myeloperoxidase, whereas in the solid tumors it amounted to only about 30% of the total. Both in cultured cells and solid tumors, 40% of the total myeloperoxidase was found in the soluble fraction and the rest in the granule fraction. However, adult and fetal blood granulocytes contained only the large myeloperoxidase, which was mainly recovered in the granule fraction. Antiserum prepared against purified large myeloperoxidase of HL-60 solid tumors reacted with the small myeloperoxidase as well as the large enzyme of HL-60 cells in culture. The antiserum also precipitated myeloperoxidase of adult and fetal blood granulocytes. An Ouchterlony double immunodiffusion test also revealed their immunological identity.
mesh_terms: D000818:Animals; D002460:Cell Line; D006098:Granulocytes / Q000201:enzymology; D006801:Humans; D007942:Leukemia, Experimental / Q000201:enzymology; D015470:Leukemia, Myeloid, Acute / Q000201:enzymology*; D007962:Leukocytes / Q000201:enzymology; D051379:Mice; D008819:Mice, Nude; D009195:Peroxidase / Q000032:analysis* / Q000276:immunology; D010544:Peroxidases / Q000032:analysis*; D013347:Subcellular Fractions / Q000201:enzymology
chemical_list: D010544:Peroxidases; D009195:Peroxidase