Defining a cross-primed anti-tumor T cell signature to guide immunotherapy development

定义交叉引发的抗肿瘤 T 细胞特征来指导免疫疗法的开发

• 批准号: 10537849
• 负责人: Gabrielle Lubitz
• 金额: $ 4.52万
• 依托单位: ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-11 至 2025-07-10
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10537849
• 关键词: Address; Adoptive Transfer; Agonist; Allogenic; Animal Model; Antigen Presentation; Antigen-Presenting Cells; Antigens; Autoantigens; Automobile Driving; Breast Cancer Model; CD8-Positive T-Lymphocytes; CXCL9 gene; Cross Presentation; Cross-Priming; Dendritic Cells; Development; Exhibits; FLT3 ligand; Failure; Flow Cytometry; Immune response; Immunologic Monitoring; Immunotherapy; Inbred BALB C Mice; Interferon Type II; Interleukin-12; Interleukin-2; Intrinsic factor; Knock-out; Luciferases; Lymphoma; Measures; Mediating; Methods; Modeling; Monitor; Mus; Mutation; Outcome; Outcome Study; PD-1 blockade; Patients; Phenotype; Radiation therapy; Resistance; Role; T cell response; T cell therapy; T-Cell Activation; T-Lymphocyte; Techniques; Tissues; Tumor Antigens; Tumor-infiltrating immune cells; Vaccination; anti-PD-1; antigen-specific T cells; antitumor effect; base; cancer therapy; chemokine; cytotoxicity; design; effective therapy; immune checkpoint blockade; improved; in situ vaccination; in situ vaccine; in vivo; malignant breast neoplasm; mouse model; neoantigens; neoplastic cell; new therapeutic target; novel; patient subsets; pre-clinical; predicting response; programs; receptor; recruit; response; success; targeted treatment; therapy design; tool; transcriptome sequencing; transcriptomics; treatment response; tumor; tumor growth

PROJECT SUMMARY/ABSTRACT Immunotherapies such as checkpoint blockade have revolutionized cancer therapy, but responses are seen only in a subset of patients. Though tumor-intrinsic factors such as tumor mutational burden (TMB) or IFNγ “inflamed” signature partially predict sensitivity to checkpoint blockade, these correlations are limited—most patients with “inflamed” tumors or high TMB still fail to respond. A critical step for efficacy of T cell-mediated immunotherapies, including checkpoint blockade, is dendritic cell cross-presentation of tumor antigen (Ag) to CD8+ T cells. Cross- presentation in vivo requires Batf3-expressing type 1 dendritic cells (cDC1), though these DC have additional functions, including secretion of T cell-recruiting chemokines, driving tumor-reactive T cell (TRT) responses. Because patients with cDC1-enriched tumors have improved responses to anti-PD1, we developed an in situ vaccination (ISV) combining FLT3L, radiotherapy (XRT), and TLR agonism to enhance cDC1 cross-priming of TRT and observed that ISV potentiated anti-tumor effects of PD1 blockade and induced systemic tumor regressions in treated patients. Additionally, we have shown that adoptive transfer of tumor-specific T cells into syngeneic RAG-/- mice clears tumors, while transfer into allogeneic RAG-/- mice fails to control tumor growth, highlighting that APC cross-priming of CD8+ T cells is required for efficacy of antitumor T cells. Despite the critical role of cDC1 cross-priming of CD8+ T cells for effective therapy, there is no established method for measuring T cell cross- or direct-priming in vivo. Consequently, there is a critical need for methods to directly measure CD8+ T cell cross-priming for identifying novel therapeutic targets to enhance cross-priming, and to understand mechanisms of therapy resistance. We hypothesize that cross- and direct-primed T cells, and ISV-primed vs untreated T cells, will harbor distinct signatures, mirroring their differential antitumor efficacy. In Aim 1, we will develop mouse models of cross- and direct-priming using H2Kd knockout, H2Kb-transfected, GFP/OVA- expressing lymphoma and breast cancers and transfer of Ag-specific T cells into syngeneic and allogeneic RAG-/- mice. We will sort tumor-reactive T cells and perform bulk RNA-seq and spectral flow cytometry to identify a cross-primed CD8+ T cell signature. In Aim 2, we will use bulk RNA-seq and spectral flow cytometry to characterize the T cell response to ISV and checkpoint blockade across tumors (lymphoma, breast cancer), model antigens (GFP, OVA, luciferase), and endogenous tumor antigens. The outcome of this study will be elucidation of a cross-primed CD8+ T cell phenotype and a novel immune monitoring technique that allows targeted design of novel immunotherapies by targeting novel checkpoints or costimulators to increase cross- priming of tumor-reactive T cells.

项目摘要/摘要 诸如检查点封锁之类的免疫疗法彻底改变了癌症治疗，但仅看到反应 在一部分患者中。尽管肿瘤内部因素，例如肿瘤突变烧伤（TMB）或IFNγ“发炎” 签名部分预测了对检查点封锁的敏感性，这些相关性是有限的 - 大多数患者 “发炎”肿瘤或高TMB仍然无法做出反应。 T细胞介导的免疫疗法效率的关键步骤， 包括检查点封锁，是肿瘤抗原（Ag）至CD8+ T细胞的树突状细胞横向呈递。叉- 在体内呈现需要表达BATF3型的1个树突状细胞（CDC1），尽管这些DC具有额外 功能，包括分泌T细胞促进趋化因子，驱动肿瘤反应性T细胞（TRT）反应的功能。 由于富含CDC1的肿瘤患者对抗PD1的反应改善了，我们开发了原位 疫苗接种（ISV）结合了FLT3L，放射疗法（XRT）和TLR激动剂，以增强CDC1的交叉宣传 trt并观察到ISV潜在的PD1阻断和诱导全身肿瘤的抗肿瘤效应 治疗患者的回归。此外，我们已经表明肿瘤特异性T细胞的自适应转移 合成抹布 - / - 小鼠清除肿瘤，而转移到同种异体抹布 - / - 小鼠无法控制肿瘤生长， 强调CD8+ T细胞的APC交叉染色是抗肿瘤T细胞有效性所必需的。尽管很关键 CDC1 CD8+ T细胞的CDC1交叉染色在有效治疗中，没有确定的方法来测量T 细胞交叉或直接裂化体内。因此，对于直接测量CD8+的方法至关重要 T细胞交叉染色，用于识别新型热目标以增强交叉染色并了解 治疗抗性的机制。我们假设该跨和直接提交的T细胞，以及ISV引发的VS 未处理的T细胞将带有不同的特征，以反映其差异抗肿瘤效率。在AIM 1中，我们将 使用H2KD敲除，H2KB转染，GFP/OVA-开发跨和直接染色的小鼠模型 表达淋巴瘤和乳腺癌以及将Ag特异性T细胞转移到同种异体和同种异体中 抹布 - / - 小鼠。我们将对肿瘤反应性T细胞进行排序，并执行大量的RNA-seq和光谱流式细胞仪以识别 交叉染色的CD8+ T细胞特征。在AIM 2中，我们将使用散装RNA-seq和频谱流式细胞仪到 表征T细胞对ISV的反应和检查点跨肿瘤（淋巴瘤，乳腺癌）， 模型抗原（GFP，OVA，荧光素酶）和内源性肿瘤抗原。这项研究的结果将是 阐明交叉染色的CD8+ T细胞表型和一种新型免疫监测技术，该技术允许 通过靶向新的检查点或costoimulators来增加新型免疫疗法的目标设计，以增加交叉 肿瘤反应性T细胞的启动。