Within the scientific discipline of toxicology, Cytotoxic T lymphocytes (CTLs) are generated by immune activation of cytotoxic T cells (T c cells). They are generally CD8 +, which makes them MHC class I restricted. CTLs are able to eliminate most cells in the body since most nucleated cells express class I MHC molecules.

There are three main pathways that CTLs use to kill target cells: the death ligand pathway, production of cytokine interferon gamma (IFNγ), and the cytotoxic granule pathway.

Cytotoxic CD8 T cells carry out their killing function by releasing two types of preformed cytotoxic protein: the granzymes, which seem able to induce apoptosis in any type of target cell, and the pore-forming protein perforin, which punches holes in the target-cell membrane through which the granzymes can enter.

Cytotoxic T cells are a key part of the cellular immune response, killing cells that display foreign antigen on their surface, primarily virus-infected cells. Transformed cells can also be detected and eliminated by cytotoxic T cells.

Cellular cytotoxicity, the ability to kill other cells, is an important effector mechanism of the immune system to combat viral infections and cancer. Cytotoxic T cells and natural killer (NK) cells are the major mediators of this activity. Here, we …

Jul 16, 2010 · CTLs and NK cells use both a perforin-dependent and a death receptor-dependent pathway to exert their cytotoxic function. These pathways have key functions in both immune surveillance and...

May 9, 2017 · Cytotoxic T lymphocytes (CTLs) are critical in the elimination of infected or malignant cells and are emerging as a major therapeutic target. How CTLs recognize and kill harmful cells has been characterized in vitro but little is …

May 1, 2003 · Granzyme A, the most abundant granzyme, which is expressed by both innate and adaptive immune cytotoxic cells, activates a new caspase-independent cell-death pathway that targets a newly...

Apr 28, 2023 · The importance of this cytotoxic pathway in immune regulation is evidenced by the severe and often fatal condition, known as hemophagocytic lymphohistiocytosis (HLH) that occurs in mice and humans with inborn errors of lymphocyte cytotoxic function.

In this review, I discuss recent insights into the mechanisms of granule-mediated cytotoxicity, focusing on how granzymes A, B and C and granulysin activate cell death through caspase-independent pathways.