Memory CD8+ T cells mediate antibacterial immunity via CCL3 activation of TNF/ROI+ phagocytes.

ABSTRACT: Cytolysis, interferon gamma and tumor necrosis factor (TNF) alpha secretion are major effector mechanisms of memory CD8+ T cells that are believed to be required for immunological protection in vivo. By using mutants of the intracellular bacterium Listeria monocytogenes, we found that none of these effector activities is sufficient to protect against secondary infection with wild-type (WT) bacteria. We demonstrated that CCL3 derived from reactivated memory CD8+ T cells is required for efficient killing of WT bacteria. CCL3 induces a rapid TNF-alpha secretion by innate inflammatory mononuclear phagocytic cells (MPCs), which further promotes the production of radical oxygen intermediates (ROIs) by both MPCs and neutrophils. ROI generation is the final bactericidal mechanism involved in L. mo

SUBMITTER: Narni-Mancinelli E 

PROVIDER: S-EPMC2118695 | biostudies-literature | 2007 Sep

REPOSITORIES: biostudies-literature