Mice unresponsive to GM-CSF are unexpectedly resistant to cutaneous Leishmania major infection

Abstract

Granulocyte-macrophage colony-stimulating factor (GM-CSF) has been shown to play a protective role in leishmanial infection. Mice with a null mutation in the gene for the beta common (βc) chain of the receptors for GM-CSF, interleukin(IL)-3 and IL-5 (βc-null mice) display normal steady state hemopoiesis and develop lung disease similar to the human condition, alveolar proteinosis, due to a lack of signaling by GM-CSF. We therefore expected to observe a heightened sensitivity to Leishmania major in the βc-null mice. Surprisingly, the βc-null mice were more resistant to cutaneous infection than wild-type (wt) mice. Upon intradermal injection of L. major promastigotes, fewer βc-null mice develo..