T-Lymphocyte and Natural Killer Cell

**Semantic type:** Cell

**Definition:** Group of lymphocytes. A T-lymphocyte is a white blood cell differentiated in the thymus that possesses highly specific cell-surface antigen receptors. A natural killer cell resembles a T-lymphocyte, but it does not express markers of either T or B cell lineage. Its cytotoxic activity is not antibody dependent.

**Synonyms:** - T-Lymphocyte and NK-Cell