cytotoxic T lymphocytes
(CTL) differentiated T lymphocytes that can recognize and lyse target cells bearing specific antigens recognized by their antigen receptors. Recognition is MHC restricted; the foreign antigen is recognized only in association with self MHC antigens. The cytotoxic activity requires firm binding of the lymphocyte to the target cell to produce holes in the plasma membrane of the target cell, loss of its cell content, and osmotic lysis. These lymphocytes are important in graft rejection and killing of tumor cells and virus-infected host cells. Murine killer T cells are marked by the Ly-2 and Ly-3 antigens, human cells by the CD4 and CD8 antigens. Called also killer or killer T cells.
Medical dictionary.
2011.