基因编辑技术筛选乳腺癌免疫靶点
由于细胞毒性T淋巴细胞可以通过细胞膜表面的CD8受体杀死恶性肿瘤细胞、病毒感染细胞以及其他受损细胞，故CD8受体阳性T淋巴细胞对于抗肿瘤免疫应答具有重要作用。
2019年8月22日，全球自然科学三大旗舰期刊之一、美国《细胞》正刊发表耶鲁大学陈斯迪等青年学者的研究报告，通过基因编辑技术，对体内CD8受体阳性T淋巴细胞进行全基因组筛选，发现了三阴性乳腺癌全身免疫治疗的新靶点。
该研究在接受免疫治疗的三阴性乳腺癌小鼠模型体内，通过CRISPR基因编辑技术，直接对CD8受体阳性T淋巴细胞进行全基因组筛选，确定CD8受体阳性T淋巴细胞浸润肿瘤并分泌细胞毒性颗粒的调节因子。体内筛选既可以强有力地再次证实已知的免疫治疗经典靶点，例如细胞程序性死亡蛋白PD-1和T淋巴细胞免疫球蛋白和黏蛋白结构分子TIM-3，还可以发现T淋巴细胞尚未发现的靶基因。
结果，通过全基因组体内筛选发现，核糖核酸RNA解旋酶DHX37可以对CD8受体阳性T淋巴细胞浸润肿瘤并分泌细胞毒性颗粒进行调控。利用基因技术剔除DHX37编码基因，可以增强抗体特异性CD8受体阳性T淋巴细胞对体内三阴性乳腺癌的杀伤作用。小鼠和人类CD8受体阳性T淋巴细胞的免疫学特征分析表明，DHX37可以抑制效应分子的功能、细胞因子的产生、T淋巴细胞的活化。转录组学和生物化学的作用机制分析表明，DHX37可以与PDCD11发生相互作用，并且影响细胞核因子NF-κB基因转录活性。
因此，该研究结果表明，高通量体内基因筛选可以用于探索免疫治疗靶点，并且确定DHX37可以调节CD8受体阳性T淋巴细胞功能，可以作为三阴性乳腺癌全身免疫治疗靶点。
Cell. 2019 Aug 22;178(5):1189-1204.e23.
Systematic Immunotherapy Target Discovery Using Genome-Scale In Vivo CRISPR Screens in CD8 T Cells.
Matthew B. Dong, Guangchuan Wang, Ryan D. Chow, Lupeng Ye, Lvyun Zhu, Xiaoyun Dai, Jonathan J. Park, Hyunu R. Kim, Youssef Errami, Christopher D. Guzman, Xiaoyu Zhou, Krista Y. Chen, Paul A. Renauer, Yaying Du, Johanna Shen, Stanley Z. Lam, Jingjia J. Zhou, Donald R. Lannin, Roy S. Herbst, Sidi Chen.
Yale University School of Medicine, New Haven, CT, USA; Yale University, West Haven, CT, USA; The College, Yale University, New Haven, CT, USA; Smilow Cancer Hospital, New Haven, CT, USA.
HIGHLIGHTS
In vivo and in vitro genome-scale CD8 T cell CRISPR screen in immunotherapy contexts
Dhx37 knockout in CD8 T cells enhances adoptive transfer efficacy
Dhx37 modulates CD8 T cell activation, cytokine production, and cytotoxicity
DHX37 interacts with PDCD11 and influences NF-κB activity
CD8 T cells play essential roles in anti-tumor immune responses. Here, we performed genome-scale CRISPR screens in CD8 T cells directly under cancer immunotherapy settings and identified regulators of tumor infiltration and degranulation. The in vivo screen robustly re-identified canonical immunotherapy targets such as PD-1 and Tim-3, along with genes that have not been characterized in T cells. The infiltration and degranulation screens converged on an RNA helicase Dhx37. Dhx37 knockout enhanced the efficacy of antigen-specific CD8 T cells against triple-negative breast cancer in vivo. Immunological characterization in mouse and human CD8 T cells revealed that DHX37 suppresses effector functions, cytokine production, and T cell activation. Transcriptomic profiling and biochemical interrogation revealed a role for DHX37 in modulating NF-κB. These data demonstrate high-throughput in vivo genetic screens for immunotherapy target discovery and establishes DHX37 as a functional regulator of CD8 T cells.
KEYWORDS: in vivo CRISPR screen; CD8 T cell; tumor infiltration; DHX37; immunotherapy; target discovery; adoptive transfer; breast cancer; T cell effector function; lentiCRISPR
DOI: 10.1016/j.cell.2019.07.044
联系客服
