T cells

T cells belong to a group of white blood cells known as lymphocytes and play a central role in cell-mediated immunity. They can be distinguished from other lymphocyte types, such as B cells and NK cells by the presence of a special receptor on their cell surface that is called the T cell receptor (TCR). The abbreviation "T", in T cell, stands for thymus since it is the principal organ for their development.
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White blood cells involved in the immune response.

A subgroup of T lymphocytes characterized by having T-cell receptor (TCR) complex and CD3 surface marker. T cells are roughly subdivided into CD4+ helper t cells and CD8+ cytotoxic and suppressor T cells.