Improving on Nature by Re-Engineering Hematopoietic Growth Factors

The hematopoietic cytokines or growth factors belong to a superfamily of proteins that regulate a variety of physiological conditions. They function as regulatory mediators by interacting with specific receptors expressed on the surface of hematopoietic and inflammatory target cells. Binding and activation of the receptors triggers a cascade of intracellular events that eventually elaborates their biological effect. Cytokines often act on a number of different cell types, frequently in concert with one another. Thus, they can have a wide-range of complex, and sometimes overlapping biological functions. In addition to playing essential roles in the growth, differentiation, and maturation of the hematopoietic cells and their precursors, cytokines have effects on inflammation, immunomodulation, angiogenesis, and apoptosis (see ref. 1).