Rapidly fatal leishmaniasis in resistant C57BL/6 mice lacking TNF.

The resolution of infections with the protozoan parasite Leishmania major in mice requires a Th1 response that is closely associated with the expression of IL-12, IFN-gamma, and inducible NO synthase. Previous Ab neutralization studies or the use of mice deficient for both TNF receptors suggested that TNF plays only a limited role in the control of parasite replication in vivo. In this study we demonstrate that resistant C57BL/6 (B6.