Specially engineered ‘young’ immune cells could help to reverse the effects of aging and the damage to brain cells caused by diseases such as Alzheimer’s, according to a new study in mice.

In their natural state, these immune cells are known as mononuclear phagocytes, and they flow around the body, cleaning up waste.

As we get older, however, these immune-cell cleaners get a bit sloppy, clearing away less cellular debris and triggering more inflammation than before. Inflammation and protein aggregation are features of many age-related diseases, including Alzheimer’s.