CELL INTELLIGENCE · 肿瘤细胞治疗研究

BACKGROUND: Diffuse middle glioma (DMG or DIPG) is a fatal pediatric brain tumor. Although chimeric antigen receptor (CAR) T-cell therapy shows promise, clinical outcomes remain inconsistent due to premature exhaustion, underscoring a critical need to improve CAR-T persistence. A major barrier to CAR-T efficacy is antigen-independent tonic signaling, yet the extent to which tonic signaling shapes CAR-T durability and clinical outcomes, particularly in DMG, remains incompletely defined. METHODS: Using a clinically investigated B7-H3 MGA271-based CAR as a reference platform, we generated alternative B7-H3 CARs incorporating either a human codon-optimized 376.96 (B7H3.BC) or Hu8H9 scFv antigen binding domain to systematically assess scFv-dependent effects on tonic signaling and therapeutic efficacy. CAR-T cells were evaluated using integrated in vitro and in vivo functional assays, alongside multi-omics profiling and computational modeling. We further derived a tonic signaling-associated gene signature and evaluated its predictive performance across independent clinical datasets. RESULTS: B7H3.BC CAR-T cells exhibit markedly restrained tonic signaling compared with MGA271- and Hu8H9-based counterparts, accompanied by superior antitumor activity and enhanced persistence across patient-derived DMG cells. Integrated multi-omics and single-cell profiling further identified a tonic signaling-associated gene signature that outperforms conventional T-cell exhaustion signatures in predicting therapeutic efficacy across multiple clinical trials, including DMG and other tumors. CONCLUSIONS: Our findings establish that scFv-dependent modulation of tonic signaling critically governs CAR-T persistence and antitumor efficacy in DMG. By linking CAR design to transcriptional and epigenetic programs, our study provides a principle-based and predictive framework to inform rational CAR engineering and improve therapeutic outcomes. Diffuse midline glioma (DMG) is a deadly childhood brain tumor with limited treatment options. CAR-T cell therapy has shown promise, but its effectiveness is often reduced because the engineered immune cells become exhausted too quickly. In this study, we found that reducing unwanted background activation, known as tonic signaling, allows CAR-T cells to persist longer and destroy tumors more effectively. We also identified a gene signature linked to tonic signaling that better predicts patient response than existing biomarkers. These findings provide a strategy to design more durable CAR-T therapies and improve outcomes for children with DMG and other difficult-to-treat cancers.