The effects of PD-1 on tumor-mediated “emergency” myelopoiesis and fate commitment of myeloid cells: Implications for anti-tumor immunity

PD-1 对肿瘤介导的“紧急”骨髓生成和骨髓细胞命运决定的影响：抗肿瘤免疫的意义

• 批准号: 10330481
• 负责人: VASSILIKI A BOUSSIOTIS
• 金额: $ 59.12万
• 依托单位: BETH ISRAEL DEACONESS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-02-10 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10330481
• 关键词: ATAC-seq; Ablation; Affect; Antibodies; B-Lymphocytes; Biogenesis; Blocking Antibodies; CD8-Positive T-Lymphocytes; Cancer Patient; Cell Differentiation process; Cell Lineage; Cell physiology; Cells; ChIP-seq; Clinical Trials; Dendritic Cells; Emergency Situation; Environment; Epigenetic Process; FRAP1 gene; Generations; Genes; Genetic; Growth Factor Receptors; Hematopoietic; Hematopoietic stem cells; ITGAM gene; Immune; Immune system; Immunity; Immunologics; Immunotherapy; Innate Immune System; Interferons; Interleukin-17; Knockout Mice; Knowledge; Lead; Ligands; Malignant Neoplasms; Mediating; Metabolic; Metabolism; Mitochondria; Modeling; Molecular; Mus; Myelogenous; Myeloid Cells; Myeloid Progenitor Cells; Myeloid-derived suppressor cells; Myelopoiesis; Outcome; Output; PD-1 blockade; PD-1 pathway; PDL1 pathway; Pathway interactions; Patients; Peroxisome Proliferator-Activated Receptors; Pharmacology; Phosphorylation; Property; Regulatory T-Lymphocyte; Role; Signal Transduction; Stress; T cell response; T-Lymphocyte; Training; Tumor Immunity; Work; anti-cancer therapeutic; cancer cell; cancer therapy; cholesterol biosynthesis; glucose uptake; granulocyte; immune activation; improved outcome; inhibitor; macrophage; metabolomics; mevalonate; monocyte; myeloid cell development; novel; pathogen; preservation; prevent; progenitor; programmed cell death ligand 1; programmed cell death protein 1; programs; response; stable isotope; success; terminally differentiated effector memory (TEM) T cells; transcriptome sequencing; tumor; tumor growth; tumor microenvironment

PD-1 blocking agents have achieved significant success as anti-cancer therapeutics. The mechanism(s) of how PD-1 compromises anti-tumor function remain poorly understood. We generated an antibody that recognizes PD-1pY248 that is required for PD-1 inhibitory signaling. In three mouse tumor models, we identified PD-1 expression and phosphorylation in CD4+ and CD8+ T cells of the tumor microenvironment (TME) but more prominently in myeloid cells. These findings prompted us to examine the role of PD-1 in myeloid cell differentiation and function in cancer immunity. The rapid change in hematopoietic cell output that occurs in response to immunologic stress is known as “emergency” myelopoiesis”. During continuous low-level stimulation mediated by cancer-derived factors, common myeloid progenitors (CMP) and granulocyte/macrophage progenitors (GMP), undergo modest but continuous expansion with hindered differentiation leading to the output of immature myeloid-derived suppressor cells (MDSC). We analyzed the myeloid compartment of tumor-bearing mice and determined that myeloid cells that expand during cancer-driven emergency myelopoiesis express PD- 1 and PD-L1. Using PD-1 KO mice or WT mice treated with PD-1 blocking antibody we determined that PD-1 deletion or blockade prevented the accumulation of immature myeloid progenitor cells and stimulated differentiation and output of Ly6Chi effector monocytes, macrophages and dendritic cells (DC). To determine whether these outcomes were mediated by a myeloid-intrinsic impact of PD-1 ablation or by the effects of PD- 1neg T cells on myeloid cells, we generated mice with conditional targeting of the Pdcd1 gene (PD-1f/f) and selectively eliminated PD-1 in myeloid cells or T cells. Compared to T cell-specific, myeloid cell-specific PD-1 ablation more effectively decreased tumor growth. Cancer-driven emergency myelopoiesis was differentially affected. Both myeloid-specific and T cell-specific PD-1 ablation resulted in expansion and accumulation of CMP but only myeloid-specific PD-1 ablation prevented the accumulation of GMP and switched the myeloid cell fate from MDSCs to differentiated effector monocytes, macrophages, DC. Our findings reveal a previously unidentified role of the PD-1: PD-L1 pathway and support the novel hypothesis that switch of myeloid cell fate commitment might be a key mechanism by which PD-1 blockade mediates its anti-tumor function. To investigate this, we will pursue the following specific aims to determine: 1. How PD-1 signaling mediates lineage fate determination of myeloid progenitor cells in response to emergency myelopoiesis. 2. How PD-1 targeting impacts the metabolic and epigenetic program of myeloid cells. 3. How PD-1 affects anti-tumor immunity by regulating the crosstalk between innate and tumor- associated T cells.

PD-1 阻断剂作为抗癌疗法取得了巨大成功。 PD-1 损害抗肿瘤功能的情况仍知之甚少，我们生成了一种可识别的抗体。 PD-1 抑制信号传导所需的 PD-1pY248 在三种小鼠肿瘤模型中，我们鉴定出了 PD-1。 肿瘤微环境 (TME) 中 CD4+ 和 CD8+ T 细胞的表达和磷酸化，但更多 这些发现促使我们研究 PD-1 在骨髓细胞中的作用。 癌症免疫中的分化和功能发生在造血细胞输出的快速变化。 在持续低水平刺激期间对免疫应激的反应被称为“紧急”骨髓生成。 由癌症衍生因子、髓系祖细胞 (CMP) 和粒细胞/巨噬细胞介导 祖细胞（GMP），经历适度但持续的扩张，分化受阻，导致输出 我们分析了荷瘤的骨髓区室。 小鼠并确定在癌症驱动的紧急骨髓生成过程中扩张的骨髓细胞表达 PD- 使用PD-1阻断抗体处理的PD-1 KO小鼠或WT小鼠，我们确定PD-1.1和PD-L1。 缺失或阻断阻止了未成熟骨髓祖细胞的积累并刺激 Ly6Chi 效应单核细胞、巨噬细胞和树突状细胞 (DC) 的分化和输出。 这些结果是由 PD-1 消融的骨髓固有影响介导的，还是由 PD-1 的影响介导的？ 1neg T 细胞在骨髓细胞上，我们生成了有条件靶向 Pdcd1 基因 (PD-1f/f) 的小鼠， 与 T 细胞特异性、骨髓细胞特异性 PD-1 相比，选择性消除骨髓细胞或 T 细胞中的 PD-1。 消融更有效地减少了癌症驱动的紧急骨髓细胞生成。 骨髓特异性和 T 细胞特异性 PD-1 消融都会导致 CMP 的扩张和积累。 但只有骨髓特异性 PD-1 消融才能阻止 GMP 的积累并改变骨髓细胞的命运 从 MDSC 到分化的效应单核细胞、巨噬细胞、DC。 PD-1：PD-L1 通路的未知作用并支持骨髓细胞命运转换的新假设 承诺可能是 PD-1 阻断介导其抗肿瘤功能的关键机制。 为此，我们将确定以下具体目标： 1. PD-1信号如何介导骨髓祖细胞的谱系命运决定 紧急骨髓生成。 2. PD-1 靶向如何影响骨髓细胞的代谢和表观遗传程序。 3. PD-1如何通过调节先天免疫和肿瘤免疫之间的串扰影响抗肿瘤免疫 相关 T 细胞。