Irreversible electroporation (IRE) is a nonthermal ablation modality used clinically for treating unresectable tumors while preserving vital structures through controlled application of pulsed electric fields. Previous data suggest that patient outcomes are enhanced with the induction of an anti-tumor immune response, but current research focuses on using immune checkpoint inhibitors, which function through conventional immune pathways that may be down-regulated by cancer or dysregulated by chemo-induced lymphodepletion. Chimeric antigen receptor (CAR) T cells overcome this limitation, as they are engineered with synthetic receptors that redirect lymphocytes to recognize and target cells expressing tumor-specific structures. CARs are engineered to have an increased binding affinity compared to in situ T-cell binding, amplify internal stimulation cascades, and release pro-inflammatory cytokines that can modulate the endogenous immune system. However, there are still major limitations for adoptive cell therapies in solid tumors, including life-threatening on-target off-tumor cytotoxicity, antigen escape, and failure to infiltrate and persist in solid tumors. Given the substantial evidence that IRE overcomes many of the challenges associated with immune infiltration and persistence in solid tumors, there is a strong premise for using targeted cell therapies following IRE, which would then target residual cancer that could repopulate the lesion. Here, we present the first proof-of-concept combination of IRE with CAR T cells. We validated that the cell membrane CAR target is not affected in electroporated cells that survive IRE, allowing for subsequent binding and elimination of residual tumor. The research demonstrates the feasibility and synergy of a novel combination of 2 clinically used techniques.
Jacobs et al. (Thu,) studied this question.