Cytotoxic T cell

Cytotoxic T cells (also known as Tc, T cytotoxic cells or CD8+ T cells) are a type of T cell that play a key role in the immune system, particularly in the eradication of cancer cells and cells infected by viruses. These cells are known for their ability to kill malignant cells and cells infected by viruses, as well as their role in autoimmune diseases.

Function

Cytotoxic T cells are part of the adaptive immune system. Their main function is to kill cells that are infected with viruses, or that are otherwise damaged or dysfunctional. They do this by recognizing small pieces of the virus (known as antigens) on the surface of infected cells. Once they recognize these antigens, they bind to the infected cell and release chemicals that kill the cell.

Activation

Cytotoxic T cells are activated when they encounter a dendritic cell presenting an antigen that their T cell receptor (TCR) recognizes. This interaction, along with additional signals from cytokines, leads to the activation and proliferation of the cytotoxic T cell.

Mechanism of action

Once activated, cytotoxic T cells seek out and kill cells presenting the same antigen that led to their activation. They do this through a process called apoptosis, or programmed cell death. The cytotoxic T cell releases granzymes and perforin, which enter the target cell and trigger apoptosis.

Role in disease

Cytotoxic T cells play a crucial role in the control of viral infections. They are also important in the immune response against certain types of cancer. However, they can also contribute to autoimmune diseases when they mistakenly target and kill the body's own cells.

See also

• T cell
• Immune system
• Antigen
• Dendritic cell
• Apoptosis

Cytotoxic T cell

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  Antigen presentation
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  Intrathymic T Cell Differentiation
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  Killer T cells surround a cancer cell