Biosynthetic ( Recombinant ) Human Granulocyte - Macrophage Colony - Stimulating Factor : Effect on Normal Bone Marrow and Leukemia Cell

To examine the biologic properties of the molecule encoded by the human gene for granulocyte-macrophage colony-stimulating factor (GM-CSF), we expressed the cloned complementary DNA (cDNA) in transfected monkey COS cells and purified the resultant protein. Purified biosynthetic human GM-CSF was added to cultures of normal hematopoietic progenitor cells in semisolid media, and the resulting colonies were characterized cytochemically. Nonadherent light-density bone marrow cells from healthy adult volunteers were maximally stimulated with GM-CSF (approximately 250 pmol/i, and four types of colonies were consistently identified by aspirating the individual colonies and staining with a triple stain for specific and nonspecific esterases and eosinophilic granules. Pure neutrophilic granulocyte (Gh mixed granulocyte-macrophage (GM). pure macrophage (M). and pure eosinophil (EO)