Effect of various cytokines and growth factors on the interleukin-2-dependent in vitro differentiation of natural killer cells from bone marrow.

We have studied the possible role of various cytokines and growth factors on the in vitro interleukin-2 (IL-2)-dependent development of natural killer (NK) cells from bone marrow precursors. Our results indicate that tumor necrosis factor alpha and lymphotoxin augment the generation of NK cells. In contrast, interleukin-4, transforming growth factor beta and granulocyte-macrophage colony-stimulating factor significantly inhibit this phenomenon. Other factors tested, such as epidermal growth factor and fibroblast growth factor, did not detectably influence the IL-2-dependent development of NK cells.