How lymphocytes kill.

Cytotoxic T lymphocytes and natural killer cells are potent killers of target cells. These lymphocytes have large cytoplasmic granules containing cytotoxic peptides and other factors. Several of these molecules have been isolated and their functions elucidated. These molecules may be directly involved in the killing of virus-infected and transformed cells as well as in the development of cell-mediated autoimmune disorders.