Helper T-cells are a type of immune cell. They’re one of the main types of cells produced by your thymus. Helper T-cells sense when there’s an infection in your body. They activate other immune cells to fight the infection. These T-cells are an important part of your adaptive immune response.
Helper T-cells are one of the main types of immune cells. They detect infections and activate other immune cells to fight the infection.
Your thymus develops helper T-cells. The thymus is a small gland in the front of your chest. The other types of T-cells include:
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Helper T-cells are one of the most important parts of your adaptive immunity. They’re involved in almost all adaptive immune responses. They activate two types of cells:
When helper T-cells detect an infection, they form into one of two subtypes:
Helper T-cells activate other immune cells that attack and destroy foreign substances.
Helper T-cells have a receptor on their surface called a CD4 receptor. The CD4 receptor interacts with major histocompatibility complex (MHC) class II molecules. MHC class II molecules sense when there’s an infection or foreign substance in your body.
The CD4 receptor and MHC class II molecules activate the helper T-cells. The helper T-cells release molecules called cytokines. Cytokines send messages to other immune cells to start an immune response.
The cytokines released by helper T-cells help activate cytotoxic T-cells. Cytotoxic T-cells send out molecules to fight the infection. Cytotoxic T-Cells can also recognize cells that are infected and directly kill them to prevent further infection.
T-cells start in your bone marrow, the spongey substance that fills some of your bones. They move to your thymus while they’re developing. Your thymus helps your T-cells mature, and then circulates them throughout your body. Your thymus also teaches your T-cells how to know the difference between your body and the pathogen that’s infecting it.
You have numerous T-cells throughout your lymphatic system. You have high concentrations of helper T-cells 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
Helper T-cells are a type of immune cell. When they sense an infection, they activate other immune cells to fight it. They may activate cytotoxic T-cells or they may activate B-cells, which produce antibodies. Your helper T-cells are one the most important types of cells involved in your adaptive immune response.
Last reviewed by a Cleveland Clinic medical professional on 06/07/2022.
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