IL4 and infection: Interferon-gamma (IFN-γ) and tumor necrosis factor (TNF) -α and -β, from the Th1 profile, are known to be involved in the resistance and elimination of the parasites, while Th2 cytokines such as IL-4 and IL-10 are linked to susceptibility to infections by Leishmania (Von Stebut, 2007; de Assis Souza et al., 2013).