Low dosages of interleukin 1 protect mice against lethal cerebral malaria

Abstract

In cerebral malaria, pathological changes can be found in the brain of infected people and in the brain of Plasmodium berghei-infected mice. The pathogenesis of cerebral malaria in mice is believed to be due to an immunopathological reaction giving rise to an excessive production of cytokines such as interferon γ (IFN-γ) and tumor necrosis factor (TNF). We find that low doses of interleukin 1 (IL-1) protect mice against cerebral malaria; IL-1 also inhibits parasitemia. The IL-1 effect on parasitemia was not observed in nude mice and was at least partly reversed in mice treated with IL-1 in combination with antibody to IFN-γ, indicating the involvement of T cells. Mice protected against development of cerebral malaria by IL-1 treatment developed the syndrome when TNF was given as observed in control infected mice or infected mice treated with inactivated IL-1.