Hematologic growth factors are hormones that increase blood cell production. Commercially
available since the late 1980s,
they are used to raise blood counts in a variety of medical situations. Genetically engineered erythropoietin, which
stimulates red blood cell growth in the bone marrow, is
available for treatment of anemias associated with kidney failure, cancer chemotherapy, and certain AIDS medications. Neutrophil growth factors are available to help increase low white blood cell counts associated with,cancer chemotherapy and bone marrow transplantation and are also used in the harvest of stem cells from bone marrow donors. Uses for these agents are constantly increasing. Clinical trials are in progress for stem cell factor, which stimulates more primitive bone marrow cells, and thrombopoietin, which stimulates platelet production. Other types of growth factors include the interleukins, some of which are used to stimulate blood cell growth, and others of which are used to treat certain types of cancer.