In a recent paper published in Immunity, Xu and colleagues demonstrate that enhancing chimeric antigen receptor(CAR)clustering via liquid-liquid phase separation, particularly through the inclusion of CD3ε, improves immunological synapse(IS)formation, antigen sensitivity, and long-term cytotoxicity. Their optimized CAR design (E_B6I28Z) mimics key features of TCR-based IS, reducing exhaustion and improving responses against both hematological and solid tumors.