TNF and infection: Although it was impossible for us to measure the cytokine levels in the tumor microenvironment at the early days of infection(1–7 days post infection), our current results may be a reflection of our earlier report that Plasmodium infection upregulates the production of proinflammatory cytokines(IL-2, IFNγ and TNF-α) in peripheral blood during the early stage of infection, peaks at day 7, and declines to a minimal level 14 days post infection [63].