[Effect of cytokines on eosinophil differentiation and proliferation]

IL-3, IL-5, and GM-CSF are eosinopoietic cytokines that induce the proliferation and differentiation of eosinophils. However, the regulatory mechanism of eosinopoiesis is largely unknown. A combination of IL-3 and IL-5 induces selective proliferation and differentiation of eosinophils from mononuclear cell fractions of human cord blood. IFN-gamma decreases the IL-3- and IL-5-induced eosinophil differentiation in a dose-dependent manner. IL-4 and IL-2 also decrease the IL-3- and IL-5-induced eosinophil differentiation. These observations indicate that IL-2, IL-4, and IFN-gamma have a direct or indirect inhibitory effect on eosinopoiesis.