The Function of Hematopoietic Growth Factors
1. Growth factors that induce proliferation of hematopoietic precursor cells often enhance the functional activity of the terminally differentiated progeny of those precursor cells.
2. Factors that stimulate hematopoiesis can do so directly or indirectly.
3. Most of the hematopoietic growth factors and cytokines function synergistically with other growth factors and/or cytokines.
4. The hematopoietic regulatory cytokine network is organized hierarchically.
5. The network exhibits many signal amplification circuits.
6. Colony-stimulating factors act by binding to specific cell surface receptors that then induce the cell to proliferate or differentiate.