UCL research shows that T cells behave differently in older people

T cells are part of adaptive immunity, the part of the immune system that is trained to recognise specific foreign invaders. It is this branch of immunity that we train when we vaccinate. For years, scientists believed that T cells from older people stopped functioning properly as a result of a process called “senescence” – essentially the loss of a cell’s ability to replicate. The Akbar lab has now discovered that instead of becoming useless, old T cells switch their focus by acquiring functions not usually associated with them. These functions help T cells combat stresses more frequently encountered in ageing organs – older, damaged and pre-cancerous cells.

The researchers went on to discover that a family of stress-sensing proteins, called sestrins, drive this altered T cell function by causing expression on the cell surface of proteins usually associated with natural killer cells. These allow killer T cells to target cells for death using different cellular machinery than is conventional.

Prof. Akbar adds: “It is now hoped that the combination of sestrins and natural killer receptors can provide what may well be tractable therapeutic targets to improve traditional T cell function in older people.”