A protein notorious for its role in Alzheimer’s disease may hold the key to supercharging the aging immune system, according to new research. As has been seen with some other health conditions, such as obesity, there exists a paradox between cancer and Alzheimer’s disease. That is, research has repeatedly shown that people with Alzheimer’s disease are less likely to develop cancer. They took T cells from Alzheimer’s mice and transferred them into non-Alzheimer’s mice with cancer to see if the immune cells alone could slow tumor growth. Cancers grew much more slowly in Alzheimer’s mice; even transferring T cells from Alzheimer’s mice into non-Alzheimer’s mice made tumors shrink, showing that the effect was immune-driven, not just due to Alzheimer’s factors.