The mechanisms by which CD8+ T cells mediate immunity against bacterial pathogens remain largely unknown. Perforin-dependent cytolysis plays a role, but is not required for CD8+ T cell-mediated immunity against Listeria monocytogenes. TNF is essential for CD8+ T cell immunity to L. monocytogenes, but the cellular source of TNF is undefined. TNF-deficient and TNF/perforin double-deficient mice w...