Recombinant cytokines Colony-stimulating factors (CSF), such as erythropoietin, granulocyte CSF (G-CSF), and granulocyte-macrophage CSF (GM-CSF), are used in patients undergoing chemotherapy or transplantation for hematologic disorders and cancers and in patients with severe chronic neutropenia (see table Some Immunotherapeutic Agents in Clinical Use).