Schelker Roland C, Fioravanti Jessica, Mastrogiovanni Fabio, Baldwin Jeremy G, Rana Nisha, Li Peng, Chen Ping, Vadász Timea, Spolski Rosanne, Heuser-Loy Christoph, Slavkovic-Lukic Dragana, Noronha Pedro, Damiano Giuseppe, Raccosta Laura, Maggioni Daniela, Pullugula Sree, Lin Jian-Xin, Oh Jangsuk, Grandinetti Patrick, Lecce Mario, Hesse Leo, Kocks Emilia, Martín-Santos Azucena, Gebhard Claudia, Telford William G, Ji Yun, Restifo Nicholas P, Russo Vincenzo, Rehli Michael, Herr Wolfgang, Leonard Warren J, Gattinoni Luca
Division of Functional Immune Cell Modulation, Leibniz Institute for Immunotherapy, Regensburg, Germany.
Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
Signal Transduct Target Ther. 2024 Aug 9;9(1):199. doi: 10.1038/s41392-024-01915-z.
High frequencies of stem-like memory T cells in infusion products correlate with superior patient outcomes across multiple T cell therapy trials. Herein, we analyzed a published CRISPR activation screening to identify transcriptional regulators that could be harnessed to augment stem-like behavior in CD8 T cells. Using IFN-γ production as a proxy for CD8 T cell terminal differentiation, LMO4 emerged among the top hits inhibiting the development of effectors cells. Consistently, we found that Lmo4 was downregulated upon CD8 T cell activation but maintained under culture conditions facilitating the formation of stem-like T cells. By employing a synthetic biology approach to ectopically express LMO4 in antitumor CD8 T cells, we enabled selective expansion and enhanced persistence of transduced cells, while limiting their terminal differentiation and senescence. LMO4 overexpression promoted transcriptional programs regulating stemness, increasing the numbers of stem-like CD8 memory T cells and enhancing their polyfunctionality and recall capacity. When tested in syngeneic and xenograft tumor models, LMO4 overexpression boosted CD8 T cell antitumor immunity, resulting in enhanced tumor regression. Rather than directly modulating gene transcription, LMO4 bound to JAK1 and potentiated STAT3 signaling in response to IL-21, inducing the expression of target genes (Tcf7, Socs3, Junb, and Zfp36) crucial for memory responses. CRISPR/Cas9-deletion of Stat3 nullified the enhanced memory signature conferred by LMO4, thereby abrogating the therapeutic benefit of LMO4 overexpression. These results establish LMO4 overexpression as an effective strategy to boost CD8 T cell stemness, providing a new synthetic biology tool to bolster the efficacy of T cell-based immunotherapies.
在多项T细胞治疗试验中，输注产品中高频率的干细胞样记忆T细胞与患者的优异预后相关。在此，我们分析了一项已发表的CRISPR激活筛选，以确定可用于增强CD8 T细胞干细胞样行为的转录调节因子。使用IFN-γ产生作为CD8 T细胞终末分化的替代指标，LMO4在抑制效应细胞发育的顶级命中基因中出现。一致地，我们发现Lmo4在CD8 T细胞激活后下调，但在促进干细胞样T细胞形成的培养条件下维持。通过采用合成生物学方法在抗肿瘤CD8 T细胞中异位表达LMO4，我们实现了转导细胞的选择性扩增和增强的持久性，同时限制了它们的终末分化和衰老。LMO4过表达促进了调节干性的转录程序，增加了干细胞样CD8记忆T细胞的数量，并增强了它们的多功能性和回忆能力。在同基因和异种移植肿瘤模型中进行测试时，LMO4过表达增强了CD8 T细胞的抗肿瘤免疫力，导致肿瘤消退增强。LMO4不是直接调节基因转录，而是与JAK1结合并增强对IL-21的STAT3信号传导，诱导对记忆反应至关重要的靶基因（Tcf7、Socs3、Junb和Zfp36）的表达。Stat3的CRISPR/Cas9缺失消除了LMO4赋予的增强记忆特征，从而消除了LMO4过表达的治疗益处。这些结果确立了LMO4过表达作为增强CD8 T细胞干性的有效策略，为增强基于T细胞的免疫疗法的疗效提供了一种新的合成生物学工具。
