GRANULOCYTE-COLONY-STIMULATING FACTOR INHIBITS THE ENDOGENOUS LEUKOTRIENE PRODUCTION IN TUMOR PATIENTS

Granulocyte colony-stimulating factor (G-CSF) is virtually devoid of inflammatory side-effects when given to patients in therapeutic doses. This is in contrast to other haemopoietic cytokines such as granulocyte-macrophage colony-stimulating factor (GM-CSF) or interleukin-3 (IL-3) which may promote inflammatory reactions by increasing the number and/or activity of monocytes, eosinophils, mast cells and basophils. Inflammatory reactions to GM-CSF and IL-3 appear to be related to an increased formation of leukotrienes, known as potent mediators of allergy and inflammation. Here we report that, in contrast to GM-CSP or IL-3, G-CSF has the potential to inhibit the leukotriene production in vivo. G-CSF may thus act as an anti-inflammatory agent. The differential effects bf G-CSF and other haemopoietins on endogenous leukotrienes may be of major clinical significance.