Granzymes

Definition

Granzymes are serine proteases released by cytotoxic T cells and natural killer (NK) cells. These enzymes induce apoptosis in target cells, thereby playing a crucial role in immune defense.

5 Must Know Facts For Your Next Test

1. Granzymes enter target cells through pores formed by perforin.
2. Granzyme B is the most studied and is involved in cleaving proteins to initiate apoptosis.
3. They contribute to the elimination of virus-infected and cancerous cells.
4. Granzymes can activate caspases, which are key enzymes in the apoptotic pathway.
5. In addition to their role in killing infected or malignant cells, granzymes also help regulate inflammation.

Review Questions

• How do granzymes enter target cells?
• What is the primary function of granzyme B?
• Which types of immune cells release granzymes?

Related terms

Perforin: A protein that forms pores in the membranes of target cells, allowing granzymes to enter.

Apoptosis: A programmed cell death process essential for removing unwanted or dangerous cells.

Cytotoxic T Cells: A subset of T lymphocytes that kill cancer cells, virus-infected cells, and damaged cells.