How do colony-stimulating factors control the production of white blood cells?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Illustration of a blood vessel with a cutaway view showing red blood cells, white blood cells, platelets, and plasma, each labeled to highlight the main components of blood. — white blood cell Blood is made up of multiple components, including red blood cells, white blood cells, platelets, and water-rich plasma.

Colony-stimulating factors (CSFs) are a group of cytokines that regulate the formation of white blood cells by acting on hematopoietic stem cells within the bone marrow. These proteins facilitate communication between cells to encourage stem cells to differentiate into specific types of mature white blood cells needed to combat infection and inflammation.1

Different types of CSFs target specific lineages of cells:

Granulocyte colony-stimulating factor (G-CSF): Promotes the development of neutrophils, which are vital for fighting bacterial infections.1
Granulocyte-macrophage colony-stimulating factor (GM-CSF): Stimulates the production of both granulocytes and monocytes, which mature into macrophages.1
Macrophage colony-stimulating factor (M-CSF): Primarily encourages the formation and function of monocytes and macrophages.1
Interleukin-3 (IL-3): Often called multi-CSF, this molecule binds to specific receptors on stem cells to support the growth of a broader range of cells, including white blood cells, red cells, and platelets.1

By guiding this development, CSFs ensure the body maintains an adequate immune response.1