Publisher Summary In the last decade, several clonal techniques have been developed for
studying hemopoietic cells in vitro. It was reported that mouse bone marrow cells would form
colonies of granulocytes and macrophages when plated in a soft gel medium, provided a
suitable source of colony-stimulating factor was present. These granulocyte colony-forming
cells (or CFU,) have since been detected in a variety of species, including man. More
recently, it has been shown that under suitable conditions and using appropriate stimulating …