Biological activities of interleukins and colony-stimulating factors

The complementary DNAs encoding interleukins (interleukins 1, 2, 3, 4, 5 and 6) and colony-stimulating factors (granulocyte-macrophage, granulocyte, and macrophage colony-stimulating factors) have been cloned. These DNA clones have allowed the large-scale production of recombinant forms of these cytokines and the extensive studies of their biological activities. These advances have led to a much better understanding of the role of these cytokines in regulation of immune responses and hematopoiesis, and have clarified that these cytokines have multiple effects on various types of cells.