美国哥伦比亚大学Benjamin Izar课题组通过碱基编辑筛选，绘制出原代人类T细胞抗肿瘤特征的变异效应图谱。2024年5月23日，《自然—生物技术》杂志在线发表了这项成果。

研究人员进行了大规模并行碱基编辑筛选，在注释为已知或潜在临床相关性的基因位点上产生了数千个变异。研究人员发现了大量功能增益（GOF）和功能缺失（LOF）突变，包括PIK3CD及其调控亚基、PIK3R1、LCK、SOS1、AKT1和RHOA的编码基因。在具有黑色素瘤表位特异性工程T细胞受体的T细胞或不同代CD19嵌合抗原受体（CAR）T细胞中对PIK3CD和PIK3R1变体进行碱基编辑，结果表明，发现的GOF变体（而非LOF或沉默突变对照）可分别增强信号传导、细胞因子产生以及同源黑色素瘤和白血病细胞模型的裂解。

此外，研究人员还表明，利用PIK3CD GOF突变设计的几代CD19 CAR T细胞显示出更强的抗原特异性信号传导、细胞因子产生和白血病细胞杀伤能力，包括与其他最新策略进行比较时也是如此。

据悉，关键T细胞基因中的单核苷酸变异（SNV）可导致临床病理变化，并可重新用于改善细胞癌症免疫疗法。

附：英文原文

Title: Mapping variant effects on anti-tumor hallmarks of primary human T cells with base-editing screens

Author: Walsh, Zachary H., Shah, Parin, Kothapalli, Neeharika, Shah, Shivem B., Nikolenyi, Gergo, Brodtman, D. Zack, Leuzzi, Giuseppe, Rogava, Meri, Mu, Michael, Ho, Patricia, Abuzaid, Sinan, Vasan, Neil, AlQuraishi, Mohammed, Milner, Joshua D., Ciccia, Alberto, Melms, Johannes C., Izar, Benjamin

Issue&Volume: 2024-05-23

Abstract: Single-nucleotide variants (SNVs) in key T cell genes can drive clinical pathologies and could be repurposed to improve cellular cancer immunotherapies. Here, we perform massively parallel base-editing screens to generate thousands of variants at gene loci annotated with known or potential clinical relevance. We discover a broad landscape of putative gain-of-function (GOF) and loss-of-function (LOF) mutations, including in PIK3CD and the gene encoding its regulatory subunit, PIK3R1, LCK, SOS1, AKT1 and RHOA. Base editing of PIK3CD and PIK3R1 variants in T cells with an engineered T cell receptor specific to a melanoma epitope or in different generations of CD19 chimeric antigen receptor (CAR) T cells demonstrates that discovered GOF variants, but not LOF or silent mutation controls, enhanced signaling, cytokine production and lysis of cognate melanoma and leukemia cell models, respectively. Additionally, we show that generations of CD19 CAR T cells engineered with PIK3CD GOF mutations demonstrate enhanced antigen-specific signaling, cytokine production and leukemia cell killing, including when benchmarked against other recent strategies.

DOI: 10.1038/s41587-024-02235-x

Source: https://www.nature.com/articles/s41587-024-02235-x