MIT scientists find a way to rejuvenate the immune system as we age

As the immune system weakens with age, scientists have found a way to restore some of its lost strength. By delivering mRNA to the liver, they created a temporary source of immune-boosting signals that normally come from the thymus. Older mice treated this way produced more effective T cells and responded far better to vaccines and cancer treatments. The strategy could one day help extend healthy years of life.