Cellular and Humoral Mechanisms of Cytotoxicity: Structural and Functional Analogies

Target cell (TC) killing, however, is not restricted to immune cells and has been documented for various cell types, including bacteria, fungi, yeast, plant cells, and protozoan parasites. Perhaps one denominator common to all these different cytotoxic cell types and their killing machineries is the involvement of soluble cytotoxic mediators that are secreted by the killer cell and used to lyse the target. The increased interest in these soluble mediators of cell killing, generally referred to as “cytotoxins,” has been greatly stimulated in part by the feasibility of their isolation in the laboratory in high yields and their further characterization by conventional biochemical techniques. This chapter focuses on the molecular mechanisms of membrane. The surprising functional analogies between the cytotoxin released by lymphocytes and the better known toxins found in certain bacteria and insects, for example, should greatly stimulate and aid future studies on the cytotoxic reaction mediated by immune cells.