自杀基因作为一种“安全性开关”控制CAR-T细胞毒性的临床前研究

目的：探讨小分子化学诱导药AP1903能否在体内外终止过表达iCasp9自杀基因的CD19靶向嵌合抗原受体修饰T（CD19CAR-T）细胞毒性功能。方法：构建过表达iCasp9的CD19CAR-T（iCasp9-CD19CAR-T）细胞并和AP1903共孵育，采用流式细胞术检测细胞表型及凋亡的方法，分别在K562和T细胞上验证iCasp9/CID自杀基因系统，在体内（观察荷Raji细胞移植瘤NCG小鼠的生存率）和体外（流式细胞术检测细胞的杀伤功能）检测AP1903给药情况下iCasp9-CD19CAR-T细胞的杀伤功能。结果：和 CD19CAR-T 细胞相比，iCasp9-CD19CAR-T 细胞的增殖能力、表型及体内外杀伤功能均无显著差异（均 P>0.05）。AP1903给药2 h后双表达iCasp9和CD19CAR的K562和T细胞分别有（33.8±0.9）%和（27.95±0.35）%的细胞出现凋亡，AP1903给药 24 h 后双表达 iCasp9 和 CD19CAR 的 K562 和 T 细胞均已经全部死亡。检测 AP1903 给药和未给药两种条件下的 iCasp9-CD19CAR-T细胞体外杀伤效率，前者明显低于后者（P<0.01）；iCasp9-CD19CAR-T细胞治疗荷Raji细胞移植瘤NCG小鼠，其60 d 生存率同样是AP1903给药的明显低于未给药的（P<0.01）。结论：小分子化学诱导药物AP1903能在体内外有效终止iCasp9-CD19CAR-T细胞毒性功能。     

Augmenting TCR signal strength and ICOS costimulation results in metabolically fit and therapeutically potent human CAR Th17 cells

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CAR-T新型联用策略治疗实体瘤研究进展

近年来，嵌合抗原受体T细胞（chimeric antigen receptor T-cell，CAR-T）疗法在血液肿瘤的治疗中取得了突破性进展，但是在实体瘤的治疗中仍然存在着诸多问题，例如CAR-T细胞渗透性差，易发生T细胞耗竭现象、脱靶效应等，故实体瘤的CAR-T疗法需要提出新的治疗策略来提升治疗效果。与单一CAR-T治疗方式相比，CAR-T联合其他肿瘤治疗手段已经在临床前及临床研究中展现出优异疗效。本篇综述总结了CAR-T联用不同肿瘤治疗方法：抗体药物、溶瘤病毒、肿瘤疫苗、纳米药物应对实体瘤治疗的研究进展，以期为开发新的CAR-T联用策略治疗实体瘤提供理论依据和新思路。     

FEN1 inhibitor SC13 promotes CAR-T cells infiltration into solid tumours through cGAS–STING signalling pathway

It is well known that chimeric antigen receptor T-cell immunotherapy (CAR-T-cell immunotherapy) has excellent therapeutic effect in haematological tumours, but it still faces great challenges in solid tumours, including inefficient T-cell tumour infiltration and poor functional persistence. Flap structure-specific endonuclease 1 (FEN1), highly expressed in a variety of cancer cells, plays an important role in both DNA replication and repair. Previous studies have reported that FEN1 inhibition is an effective strategy for cancer treatment. Therefore, we hypothesized whether FEN1 inhibitors combined with CAR-T-cell immunotherapy would have a stronger killing effect on solid tumours. The results showed that low dose of FEN1 inhibitors SC13 could induce an increase of double-stranded broken DNA (dsDNA) in the cytoplasm. Cytosolic dsDNA can activate the cyclic GMP–AMP synthase–stimulator of interferon gene signalling pathway and increase the secretion of chemokines. In vivo, under the action of FEN1 inhibitor SC13, more chemokines were produced at solid tumour sites, which promoted the infiltration of CAR-T cells and improved anti-tumour immunity. These findings suggest that FEN1 inhibitors could enable CAR-T cells to overcome poor T-cell infiltration and improve the treatment of solid tumours.     

Optimized CAR-T therapy based on spatiotemporal changes and chemotactic mechanisms of MDSCs induced by hypofractionated radiotherapy

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What drives CAR-T emergent cytopenia?

Prolonged cytopenia after CAR-T cell therapy is an acknowledged problem. At present, the causes and implications of prolonged cytopenia are unclear. The paper by Kitamura et al identified that prolonged cytopenia is associated with alterations in the bone marrow niche identified before CAR-T therapy, indicating a potential predictor of this serious side-effect of treatment. Commentary on: Kitamura et al. Bone marrow microenvironment disruption and sustained inflammation with prolonged haematologic toxicity after CAR T-cell therapy? Br J Haematol 2023;202:294-307.     

Derivation and validation of a novel score for early prediction of severe CRS after CAR-T therapy in haematological malignancy patients: A multi-centre study

Chimeric antigen receptor T (CAR-T) cell therapy is highly effective in inducing complete remission in haematological malignancies. Severe cytokine release syndrome (CRS) is the most significant and life-threatening adverse effect of this therapy. This multi-centre study was conducted at six hospitals in China. The training cohort included 87 patients with multiple myeloma (MM), an external validation cohort of 59 patients with MM and another external validation cohort of 68 patients with acute lymphoblastic leukaemia (ALL) or non-Hodgkin lymphoma (NHL). The levels of 45 cytokines on days 1–2 after CAR-T cell infusion and clinical characteristics of patients were used to develop the nomogram. A nomogram was developed, including CX3CL1, GZMB, IL4, IL6 and PDGFAA. Based on the training cohort, the nomogram had a bias-corrected AUC of 0.876 (95% CI = 0.871–0.882) for predicting severe CRS. The AUC was stable in both external validation cohorts (MM, AUC = 0.907, 95% CI = 0.899–0.916; ALL/NHL, AUC = 0.908, 95% CI = 0.903–0.913). The calibration plots (apparent and bias-corrected) overlapped with the ideal line in all cohorts. We developed a nomogram that can predict which patients are likely to develop severe CRS before they become critically ill, improving our understanding of CRS biology, and may guide future cytokine-directed therapies.     

CD30 as a therapeutic target in adult haematological malignancies: Where are we now?

CD30 is a transmembrane protein from the tumour necrosis factor receptor superfamily. It is expressed on a small subset of activated T and B lymphocytes, and various lymphoid neoplasms. CD30 is a particularly interesting treatment target because its levels are high in tumours but low in healthy tissues. Several therapeutic strategies targeting CD30 have been developed, including monoclonal antibodies, conjugated antibodies (combination of brentuximab vedotin with chemotherapy or immunotherapy), bispecific antibodies and cell and gene therapies, such as anti-CD30 CAR-T cells in particular. We briefly review the biology of CD30 which makes it a good therapeutic target, and we describe all of the anti-CD30 therapies that have emerged to date.