Killer T Cell

A cytotoxic T cell (also known as TC, cytotoxic T lymphocyte, CTL, T-killer cell, cytolytic T cell, CD8+ T-cell or killer T cell) is a T lymphocyte (a type of white blood cell) that kills cancer cells, cells that are infected (particularly with viruses), or cells that are damaged in other ways.

What do they do?
Killer T-cells find and destroy infected cells that have been turned into virus-making factories. To do this they need to tell the difference between the infected cells and healthy cells with the help of special molecules called antigens. Killer T-cells can find cells with viruses and destroy them.

How long do they live?
These methods were later used to confirm that memory T cells live for six months or less in healthy humans (Westera et al., 2013), whereas naive T cells can live for up to nine years (Vrisekoop et al., 2008). Thus, long life is not a key characteristic of memory T cells.