Clinical applications of colony-stimulating factors

Colony-stimulating factors (CSFs) are a family of regulatory glycoprotein hormones that promote the proliferation and differentiation of hemopoietic progenitor cells and augment the functions of mature effector cells in vitro. The recent cloning of human genes and the availability of sufficient quantities of recombinant purified growth factors have made it possible to evaluate their therapeutic potential in cytopenic states. Initial studies with GM-CSF have demonstrated its ability to increase neutrophil, monocyte, and eosinophil counts in patients with acquired immune deficiency syndrome (AIDS), myelodysplastic syndrome (MDS), and aplastic anemia. Both GM-CSF and G-CSF reduce the duration of neutropenia following chemotherapy and accelerate hematopoietic recovery in patients undergoing intensive chemotherapy and autologous bone marrow transplantation. Studies are now ongoing to determine the optimal dose, route, schedule of administration, and long-term effects. While the appropriate settings for the use of different CSFs remain to be determined, the initial results of clinical trials are of great interest and suggest that hematopoietic growth factors will play an important role in several clinical arenas.