T cell

One type of white blood cell that attacks virus-infected cells, foreign cells, and cancer cells. T cells also produce a number of substances that regulate the immune response. Also called T lymphocyte.

Lymphocytes which pass through the thymus gland during maturation. Different kinds of T cells play important roles in the immune response. Synonym: T lymphocyte. See: T-cell-mediated (cellular) immune response.

A type of lymphocyte responsible for attacking and destroying virus-infected cells, foreign tissue and tumor cells. Cytotoxic T- cells target a particular antigen and secrete toxic chemicals to kill the foreign cell or tissue. Other T-cells, called Helper T-cells, activate lymphocytes like B- cells and NK cells to help the body fight off invading viruses, micro- organisms and malignant cells.