TNF and parasitic infectious disease: Studies in murine models indicate that interleukin-6 (IL-6) mediates protective immunity against the pre-erythrocytic stage of malaria by inducing interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), and enhances specific immunoglobulin G (IgG) antibodies to control blood-stage parasitemia during the erythrocytic phase (Pied et al., 1992).