Granulocyte Colony-Stimulating Factor (G-CSF)-Deficient Mice

Granulocyte colony-stimulating factor (G-CSF) is a glycoprotein hemopoietic growth factor that regulates the survival, proliferation, differentiation, and function of neutrophils and their precursors (for a review, see ref. 1). Neutrophils are the most common granulocytic cell found in the blood and hemopoietic tissues. G-CSF was first purified from other granulopoietic activities in 1983 (2) and the human and murine G-CSF cDNAs and genes were cloned in 1986–1987 (3–7). G-CSF was implicated as a major regulator of murine granulopoiesis in vivo by studies of the effects of administering pharmacological doses of recombinant protein (8, 9), and of the consequences of the reconstitution of lethally irradiated mice with marrow cells infected with a recombinant retrovirus expressing G-CSF (10).