PO.IM01.11 · 免疫学
单细胞RNA-seq揭示免疫检查点抑制剂效应的新见解
Single-cell RNA-seq reveals insights into the effects of immune checkpoint inhibitors
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
免疫检查点抑制剂（ICI）已显示出卓越的临床疗效，在多种癌症中显著延长患者生存。然而，ICI调节免疫系统和记忆功能的机制仍需持续探索。单细胞RNA测序（scRNA-seq）为肿瘤学研究与开发提供了强有力的工具。在本研究中，我们在小鼠结肠腺癌模型中使用抗PD-1抗体治疗后进行了scRNA-seq。给小鼠接种MC38肿瘤细胞，用ICI治疗，随后在肿瘤消退后用相同的肿瘤细胞再次攻击。分离肿瘤浸润淋巴细胞（TIL）和外周血单个核细胞（PBMC），并结合流式细胞术使用scRNA-seq进行分析。使用10x Genomics Chromium平台处理单细胞悬液。构建、测序并预处理单细胞文库，包括去多重化和比对至参考基因组。过滤后的数据经过降维和聚类，并根据经典标志物将细胞注释为不同的细胞群。在肿瘤微环境（TME）内，我们观察到CD4⁺和CD8⁺ T细胞的显著激活、免疫抑制性CD4⁺ Treg细胞的减少以及Th1细胞的增加。在CD8⁺ T细胞中，细胞毒性效应（Teff）和记忆（Tem）亚群升高，提示有效的T细胞激活和增强的抗肿瘤免疫。同样，PBMC分析显示CD4⁺群中初始T细胞和Th1细胞增加，而CD8⁺ T细胞则表现出Tem亚群的扩增以及Teff细胞的轻微增加。总体而言，我们的发现表明，检查点阻断通过记忆T细胞的扩增和分化以及在基因和外周层面增强的免疫细胞浸润，促进了持久的抗肿瘤应答。抗PD-1治疗直接增强了TIL的肿瘤杀伤能力，促进了向有利于肿瘤清除亚型的转变。同时，治疗重塑了PBMC中的T细胞亚群，改善了分化潜能，从而强化了有效的抗肿瘤免疫应答。
查看英文原文 English abstract
Immune checkpoint inhibitors (ICIs) have demonstrated superior clinical efficacy, significantly prolonging patient survival across various cancers. However, the mechanisms by which ICIs modulate the immune system and memory function require continued exploration. Single-cell RNA sequencing (scRNA-seq) offers a powerful tool for oncology research and development. In this study, we performed scRNA-seq following treatment with an anti-PD-1 antibody in a murine colon adenocarcinoma model. Mice were inoculated with MC38 tumor cells, treated with ICIs, and subsequently re-challenged with the same tumor cells after tumor regression. Tumor-infiltrating lymphocytes (TILs) and peripheral blood mononuclear cells (PBMCs) were isolated and analyzed using scRNA-seq alongside flow cytometry. Single-cell suspensions were processed using the 10x Genomics Chromium platform. Single-cell libraries were constructed, sequenced, and pre-processed, including demultiplexing and mapping to the reference genome. Filtered data underwent dimensionality reduction and clustering, and cells were annotated into distinct populations based on classical markers. Within the tumor microenvironment (TME), we observed notable activation of CD4⁺ and CD8⁺ T cells, a reduction in immunosuppressive CD4⁺ Treg cells, and an increase in Th1 cells. Among CD8⁺ T cells, cytotoxic effector (Teff) and memory (Tem) subsets were elevated, indicating effective T-cell activation and enhanced anti-tumor immunity. Similarly, PBMC analysis revealed increased naive T cells and Th1 cells within the CD4⁺ population, while CD8⁺ T cells exhibited expansion of Tem subsets with a slight increase in Teff cells. Overall, our findings demonstrate that checkpoint blockade promotes durable anti-tumor responses through expansion and differentiation of memory T cells and enhanced immune cell infiltration at both genetic and peripheral levels. Anti-PD-1 therapy directly potentiated the tumor-killing capacity of TILs, promoting a shift toward subtypes favorable to tumor clearance. Concurrently, treatment reprogrammed T-cell subsets in PBMCs, improving differentiation potential and thereby strengthening effective anti-tumor immune responses.
利益披露 Disclosure
J. Lu, None..
J. Xiu, None..
C. Zhong, None..
W. Li, None..
W. Yun, None..
T. Pang, None..
J. Huang, None.