The production of proinflammatory cytokines IL-1β, IL-6, IL-12, TNF-α, and IFN-γ and the presence of parasite-specific T cells generating predominantly IFN-γ and low levels of IL-10 were associated with an increased efficiency of 5-LO−/− mice to control the infection within the blood and tissue compartments. This evidence concerns the gene TNF and infection.