Also called killer T cells. T cells that have been created by stimulated helper T cells. The T refers to cells of the cellular system rather than to cells of the humoral system (B cells). Cytotoxic T cells detect and destroy infected body cells by use of a special type of protein. The protein attaches to the infected cell’s membrane and forms holes in it. This allows the uncontrolled leakage of ions out of and water into the cell, causing cell death. In general, the loss of the integrity of the cell membrane leads to death. The cytotoxic T cells also transmit a signal to the (leaking) infected cells that causes the cell to “chew up” its DNA. This includes its own DNA as well as that of the virus.
A subset of T lymphocytes that carry the T8 marker and can kill body cells infected by viruses or transformed by cancer.
T lymphocyte that can destroy microorganisms directly through the release of perforin and proteolytic enzymes. They are particularly important in the defense against viruses, rejection of allografts, and, possibly, new malignant cells.