One of the most important actions of T cells is to lyse the cells expressing specific antigens. Most cells with such cytotoxic activity are CD8~+ T cells called cytotoxic T lymphocytes (CTLs).

• 具有这种细胞毒性作用的T细胞的表面抗原大部分是CD_8阳性，被称为细胞毒性T淋巴细胞(cytotoxic T lymphocytes，CTLs)。