In the murine model of invasive pulmonary aspergillosis, resistance to the infection was associated with the activation of CD4+ Th1 cells mainly producing Interferon-γ (IFN-γ), while the production of Interleukin-4 (IL-4) and Interleukin-10 (IL-10), by Th2 and Treg cells respectively, favor disease progression [8–10]. This evidence concerns the gene IL4 and infection.