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Where do T cells originate and mature?
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white blood cell
Blood is made up of multiple components, including red blood cells, white blood cells, platelets, and water-rich plasma.
T cells are a type of white blood cell that play a vital role in the immune system. They originate from stem cells located in the bone marrow.21
Following their initial formation, these prospective T cells migrate to the thymus, a pyramid-shaped lymphoid organ situated beneath the breastbone, where they undergo maturation. Within the thymus, T cells multiply and differentiate into specialized subsets—such as helper T cells, cytotoxic T cells, and regulatory T cells—before being released into the bloodstream and lymphatic system to provide immune defense.231