Trogocytosis has emerged as a key limitation of CAR-based immunotherapy, driving antigen loss, CAR downregulation, fratricide, and progressive exhaustion-associated functional impairment of engineered immune cells. This challenge is particularly critical in solid tumors, where sustained antigen engagement and repeated immune synapse formation are required for effective tumor control. Despite its significance, strategies that directly target the biophysical regulation of immune synapse dynamics remain limited.

Here, we engineered CAR-NK cells incorporating a CXCR2-derived VASP-binding motif (Vbm). Given the critical role of actin dynamics in immune synapse formation and maintenance, Vbm was designed to recruit VASP, a key regulator of actin remodeling. We hypothesized that Vbm-mediated cytoskeletal modulation could optimize effector–target cell interactions and mitigate trogocytosis-associated dysfunction.

Functionally, Vbm-engineered CAR-NK cells maintained phenotypic characteristics and short-term cytotoxic activity comparable to those of conventional CAR-NK cells. Notably, Vbm-CAR-NK cells exhibited reduced trogocytosis, fratricide, and exhaustion-associated phenotypes under prolonged stimulation conditions, resulting in enhanced long-term functional persistence in vitro. Furthermore, Vbm engineering translated into superior antitumor efficacy in vivo, supporting the therapeutic benefit of improving CAR-NK cell durability under chronic antigen exposure.

Collectively, our findings establish Vbm engineering as a novel strategy to enhance the functional durability of CAR-engineered immune cells through the mitigation of trogocytosis-associated dysfunction and highlight its potential to overcome key barriers in solid tumor immunotherapy.