Killer cell

Killer Cell

A Killer Cell is a type of white blood cell that is a key component of the immune system. These cells are known for their ability to kill cancer cells and cells infected with viruses. There are two main types of killer cells: Natural Killer Cells and Cytotoxic T Cells.

Natural Killer Cells

Natural Killer Cells (NK Cells) are a type of lymphocyte that play a major role in the host-rejection of both tumors and viral infections. They are named for their natural ability to kill cells that do not express the correct Major Histocompatibility Complex (MHC) class I molecules.

Cytotoxic T Cells

Cytotoxic T Cells (Tc Cells) are a type of T cell that kill cancer cells, cells that are infected (particularly with viruses), or cells that are damaged in other ways. They are also known as CD8+ T cells, because they express the CD8 glycoprotein at their surface.

Function

The primary function of killer cells is to fight off infections and diseases by killing the infected cells. They do this by releasing small cytoplasmic granules of proteins called perforin and granzyme that cause the target cell to die by apoptosis (cell death).

Clinical Significance

Killer cells have a significant role in the control and elimination of cancer. They are often used in immunotherapy, a type of cancer treatment that boosts the body's natural defenses to fight cancer.

See Also

• Immune System
• White Blood Cell
• Cancer
• Virus
• Immunotherapy