Researchers at Washington University reported in Science that astrocytes engineered to express chimeric antigen receptors (CAR‑As) can target and clear amyloid‑β deposits in mouse models of Alzheimer’s disease. A single prophylactic injection prevented plaque formation, and a single therapeutic dose reduced established plaque burden by about half in treated animals. The team, led by Marco Colonna, showed CAR‑As can act as a sustained cellular immunotherapy in the brain, offering an alternative to repeated monoclonal antibody dosing. Chimeric antigen receptor astrocytes are engineered glial cells that combine a target‑binding receptor with effector functions; further work will be required to assess safety, delivery, and immune effects in larger models before clinical translation.