Cytotoxic T cell responses to intracellular pathogens.

Host defense against intracellular pathogens is thought to require cytotoxic T cells. Recent studies have investigated the impact of host cell lysis and cytokine production by cytotoxic T lymphocytes on the fate of intracellular pathogens. The identification of two mechanisms of lysis induced by cytotoxic T lymphocytes--the granule exocytosis pathway and the Fas-FasL interaction--have provided new insight into the role of cytotoxic T lymphocyters in immunity to infection.