Granulopoietic effects of colony-stimulating factor obtained from urine of patients with aplastic anemia on normal and cyclophosphamide-treated mice

Colony-stimulating factor (CSF) was partially purified from urine of patients with aplastic anemia using DEAE-cellulose and concanavalin A-Sepharose. This partially purified CSF caused significant neutrophilia in the peripheral blood of normal mice by (a) single or continual intraperitoneal injection(s) in vivo, and also revealed a specific activity of 1.4 x 10(3) U/absorbance unit (AU) at 280 nm in vitro, with less than 1 ng/AU endotoxin. In addition, this CSF induced faster recoveries of neutrophils in the peripheral blood and progenitor spleen cells of cyclophosphamide (CY)-treated mice. These findings suggest that the CSF used in this study accelerated the differentiation of the granulocytic cells and the proliferation of granulocyte colony-forming units in the spleen. These effects contributed to a rapid recovery from neutropenia in mice treated with CY.