Anti-inflammatory CAR-microglia targeting Aβ for Alzheimer's disease therapy

Alzheimer's disease (AD) is characterized by the accumulation of amyloid-β (Aβ) plaques and chronic neuroinflammation, which together drive progressive neuronal loss and cognitive decline. In recent years, monoclonal antibodies targeting Aβ have demonstrated encouraging clinical benefits in Alzheimer's disease (AD). However, their therapeutic efficacy remains limited by insufficient and unsustained clearance of Aβ, as well as treatment-associated neuroinflammatory responses. These limitations highlight the need for alternative strategies that can achieve efficient Aβ elimination while maintaining immune homeostasis. To overcome these challenges, we developed a novel anti-inflammatory CAR-Microglia (CAR-Mic) incorporating a construct based on the TAM receptor family (TYRO3, AXL, and MERTK), which are key regulators of efferocytosis and anti-inflammatory responses. The resulting Aβ-targeted CAR-Mics showed enhanced Aβ engulfment and reduced proinflammatory cytokines release. Among the constructs tested, AXL-CAR demonstrated the most favorable overall performance and was therefore selected for the generation of human induced pluripotent stem cell (iPSC)-derived CAR microglia-like cells (CAR-iMGLs). In an AD mouse model, AXL-CAR-iMGLs exhibited enhanced Aβ clearance without evidence of severe adverse effects. Collectively, these findings establish TAM receptor-based CAR-iMGLs as a promising cell therapy model for AD and potentially other neurodegenerative disorders characterized by chronic neuroinflammation and defective pathological protein clearance.