Cytotoxic T-cells are one of the main types of immune cells produced in your thymus. When you have an infection, your helper T-cells activate the cytotoxic T-cells. The cytotoxic T-cells fight the infection. These T-cells are an important part of your adaptive immunity.
Cytotoxic T-cells are a type of immune cell. They destroy cells infected with viruses. Another name for cytotoxic T-cells is killer T-cells.
Cytotoxic T-cells are one of the three main types of cells developed in your thymus. The thymus is a small gland in the front of your chest. The other types of T-cells include:
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No. Cytotoxic T-cells play a role in cell-mediated immunity, a type of adaptive immunity. Innate immunity is the immunity already present in your body. You develop adaptive immunity when you’re exposed to infections or other foreign substances.
Cytotoxic T-cells attack viruses when activated by an antigen. Natural killer cells don’t need activation to attack harmful cells. Cytotoxic T-cells are part of your adaptive immune response. Natural killer cells are part of your innate immune response.
The surface of a cytotoxic T-cell has something called a CD8 receptor. The CD8 receptor interacts with cells called major histocompatibility complex (MHC) Class I molecules to recognize when healthy cells are infected.
When the CD8 receptor recognizes an infected cell, it activates the cytotoxic T-cells. The cytotoxic T-cells create molecules designed to destroy the infection.
Helper T-cells aid other cells in the immune response. When they sense an infection, they release cytokines, molecules that send messages to other immune cells. These cytokines help activate cytotoxic T-cells to fight the infection.
T-cells begin to form first in your bone marrow. They move to your thymus while they’re developing. Your thymus helps your T-cells mature and then circulates them throughout your body.
You have numerous T-cells in your lymphatic system. The highest concentrations of cytotoxic T-cells are in your:
Several types of autoimmune diseases affect your T-cells. Other conditions that affect your T-cells include:
Some lifestyle changes can keep your immune system healthy. You may:
A note from Cleveland Clinic
Cytotoxic T-cells are a type of immune cell. They are one of the main types of cells developed in your thymus. Cytotoxic T-cells help fight infections. These cells, along with helper T-cells, are an important part of your adaptive immunity. Several autoimmune diseases and other conditions can affect your T-cells.
Last reviewed by a Cleveland Clinic medical professional on 07/26/2022.
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