| abstract |
PURPOSE: To produce human differentiation including factor BUF-3 in high efficiency, by culturing an animal cell capable of producing human differentiation inducing factor BUF-3 in a culture medium and producing and accumulating BUF-3 in the medium. n CONSTITUTION: An animal cell capable of producing human differentiation including factor BUF-3 such as HL-60 of human acute promyelocytic leukemia cell, U-937 of human acute monocytic leukemia cell, etc., is cultured in a culture medium to effect the production and accumulation of BUF-3 in the medium. The culture medium (liquid) is concentrated by ultrafiltration, proteins are separated from the concentrate by salting-out and BUF-3 is produced therefrom by ion exchange chromatography. The culture of the above microorganism is usually carried out at a cell density of about 1W5×10 6 cells/ml at about 35W38°C in about 4W6% carbon dioxide gas stream under slow agitation. n COPYRIGHT: (C)1988,JPO&Japio |