Granzyme

Granzyme is a type of serine protease found in the granules of cytotoxic T cells and natural killer cells. They play a crucial role in the immune response, specifically in the elimination of virus-infected and tumor cells.

Function

Granzymes are released by cytotoxic T cells and natural killer cells upon contact with a target cell. They enter the target cell and induce apoptosis, or programmed cell death. This is a key mechanism by which the immune system eliminates cells that are infected with viruses or have become cancerous.

Types

There are several types of granzymes, including Granzyme A, Granzyme B, and Granzyme K. Each has a slightly different function and target specificity.

Granzyme A

Granzyme A is a tryptase that induces target cell death by activating a set of intracellular caspases. It is also involved in the regulation of inflammation and immune responses.

Granzyme B

Granzyme B is a chymase that induces target cell death by cleaving key proteins in the cell, leading to apoptosis. It is the most potent of the granzymes and is often used as a marker for cytotoxic T cell and natural killer cell activity.

Granzyme K

Granzyme K is a tryptase that induces target cell death by cleaving key proteins in the cell, leading to apoptosis. It is also involved in the regulation of inflammation and immune responses.

Clinical significance

Granzymes have been implicated in a number of diseases, including autoimmune diseases, cancer, and viral infections. They are also being explored as potential therapeutic targets in these conditions.

See also

• Cytotoxic T cell
• Natural killer cell
• Apoptosis
• Serine protease
• Granules