A Unified Theory for the Mechanism of the Lethal Hit by Cytotoxic T Lymphocytes (CTL) and Natural Killer (NK) Cells as Defined by Antisera Capable of Blocking the Lethal Hit Stage of Cytotoxicity
Understanding the mechanisms in which cytotoxic lymphocytes (particularly cytotoxic T lymphocytes (CTL) and natural killer (NK) cells) mediate the lysis of target cells has been a fundamental problem in molecular immunology. While these reactions involve complex biochemical and physiological processes the mechanism of cytotoxicity has been resolved into several operationally identifiable stages (1–4). In the most simplistic scheme, the effector lymphocyte must recognize and bind to the appropriate target. Subsequent to binding, the killer cell undergoes of series of physiological responses collectively termed activation. It is during this activation phase that the killer cell initiates infliction of the lethal hit on the target. Once the lethal hit has been completed the killer cell can detach and recycle to other targets. Target cells having received the lethal hit are “programmed to lyse” and will rapidly do so during the final stage of the lytic reaction known as the killer cell independent stage.
KeywordsNatural Killer Spleen Cell Murine Natural Killer Cell P815 Mastocytoma Target Cell Binding
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