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T-lymphocytes

1:55

Killer T Cell: The Cancer Assassin

3:18

Q & A: How do T-cells recognize antigens?

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Mechanism of T-CELL ACTIVATION

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Memory T Cells and Long-Term Immunity

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T Lymphocytes Overview - MCAT Mnemonic for MCAT

A T cell, or T lymphocyte, is a type of lymphocyte that plays a central role in cell-mediated immunity. T cells can be distinguished from other lymphocytes, such as B cells and natural killer cells, by the presence of a T-cell receptor on the cell surface. They are called T cells because they mature in the thymus from thymocytes. The several subsets of T cells each have a distinct function. The majority of human T cells rearrange their alpha and beta chains on the cell receptor and are termed alpha beta T cells and are part of the adaptive immune system. Specialized gamma delta T cells,, have invariant T-cell receptors with limited diversity, that can effectively present antigens to other T cells and are considered to be part of the innate immune system.