[Humoral regulation of eosinophilopoiesis by interleukin-3, granulocyte/macrophage colony-stimulating factor (GM-CSF) and interleukin-5].

In this communication, the humoral regulation of eosinophil production by interleukin-3 (IL-3), granulocyte/macrophage colony-stimulating factor (GM-CSF) and interleukin-5 (IL-5) or eosinophil differentiation factor (EDF) is described. IL-3 and GM-CSF supported early and intermediate stages of differentiation of eosinophilic progenitor cells. In contrast, IL-5 (EDF) primarily supported terminal proliferation and maturation of eosinophilic progenitor cells. Therefore, a combination of IL-3 plus IL-5, GM-CSF plus IL-5 or IL-3 plus GM-CSF plus IL-5 augmented proliferation and maturation of early and intermediate stages of eosinophilic progenitor cells. The signal transduction pathway, which explain this functional network among these three cytokines, will be elucidated in the near future.