ADPKD: Understanding immunosuppression mechanisms and discovering treatment

ADPKD：了解免疫抑制机制并发现治疗方法

• 批准号: 10468127
• 负责人: Xiaogang Li
• 金额: $ 46.51万
• 依托单位: MAYO CLINIC ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10468127
• 关键词: Address; Affect; Animal Model; Antibodies; Area; Autosomal Dominant Polycystic Kidney; Binding; Cell Communication; Cell physiology; Cells; Clinical; Collagen; Communication; Cyst; Cystic kidney; Data; Dendritic Cells; Development; Disease; Disease Progression; Epithelial Cell Proliferation; Epithelial Cells; Fibroblasts; Gel; Genetic; Growth; Human; Immune; Immune Evasion; Immune response; Immune system; Immunologic Surveillance; Immunosuppression; Immunosuppressive Agents; Immunotherapy; Inflammation; Investigation; Kidney; Knock-out; Knockout Mice; Ligands; Mediating; Migration Inhibitory Factor; Mus; Mutant Strains Mice; Patients; Play; Population; Publications; Reporting; Role; Signal Transduction; Stimulus; Structure; Surface; T-Cell Activation; T-Cell Receptor; T-Lymphocyte; TNF gene; Testing; Time; Tissues; Tumor Escape; Tumor-infiltrating immune cells; Up-Regulation; Urine; cancer cell; cytokine; exosome; human model; humanized antibody; improved; in vivo; inhibitor; interstitial; lymphocyte proliferation; macrophage; mouse model; mutant; mutant mouse model; neoplastic cell; novel therapeutic intervention; pre-clinical; programmed cell death ligand 1; programmed cell death protein 1; recruit; renal epithelium; tumor; tumor microenvironment; tumor-immune system interactions; urinary

Summary The immune system plays an important role in protecting us from disease. Interstitial inflammation has been consistently reported in human and animal models of ADPKD, and it may become worse during cyst expansion which results in more damages in renal parenchyma. In addition to the increase of macrophages in the interstitium and pericystic areas, T lymphocytes are also increased in cystic kidneys. However, whether and how PKD mutant cystic renal epithelial cells escapes immune attacks in cystic microenvironment during cyst initiation and expansion remains elusive. In this study, we investigate the roles of programmed cell death protein 1 (PD-1) and programmed death ligand-1 (PD-L1), a PD-1 ligand, in ADPKD. We found that, 1) PD-1 was upregulated on T cells in Pkd1 mutant kidneys; 2) PD-L1 was upregulated in Pkd1 mutant renal epithelial cells and tissues, and was increased in cystic cell derived exosomes; 3) knockout of Pd-l1 delayed cyst growth and increased the survival of Pkd1 knockout mice; 4) targeting PD1 and PD-L1 with antibodies delayed cyst growth in Pkd1 knockout kidneys; 5) treatment with exosomes isolated from cystic renal epithelial cells and urine of ADPKD patients increased Pkd1 wild type renal epithelial cell proliferation, and induced the activation of PKD associated signaling in these cells; 6) treatment with cystic renal epithelial cell derived exosomes promoted cyst growth in Pkd1 mutant kidneys; 7) renal epithelial cells (NRK-52E cells) treated with ADPKD urinary exosomes also developed cysts-like structures in collagen gels; and 8) inhibition of exosome secretion with GW4869 delays cyst growth in Pkd1 knockout kidneys. Our central hypothesis is that upregulation of PD-L1 on cystic renal epithelial cells and PD-1 on T cells results in immune evasion of cystic cells via inhibition of T cell function, and exosomes secreted by cystic renal epithelial cell regulate immunosuppression via adjacent T cells and the function of other neighboring cells, including renal epithelial cells and fibroblasts, contributing to cyst growth. We test this hypothesis with three specific aims. This study will determine for the first time whether PD-1 and PD-L1 are immune-suppressors in cystic kidneys, which helps cystic epithelial cells to escape immune attack in ADPKD, and whether exosomes secreted by cystic epithelial cells contribute to immune suppression and other cellular communication. In addition, we will determine whether PD1 and PD-L1 are effective targets to slow disease progression in preclinical setting. Accomplishing this study will lead to a better understanding of the mechanism of immune surveillance in renal cyst formation and the roles of cystic cell exosomes in regulating immunosuppression and other cell-to-cell communication, which will provide novel therapeutic strategy for ADPKD treatment.

概括 免疫系统在保护我们免受疾病侵害方面发挥着重要作用。间质炎症有 在 ADPKD 的人类和动物模型中得到一致报道，并且在囊肿期间情况可能会变得更糟 扩张导致肾实质更多损伤。除了巨噬细胞的增加 在间质和囊周区域，囊性肾中 T 淋巴细胞也增多。然而， PKD突变囊性肾上皮细胞是否以及如何逃避囊性肾中的免疫攻击 囊肿起始和扩张过程中的微环境仍然难以捉摸。在这项研究中，我们调查了角色 程序性细胞死亡蛋白 1 (PD-1) 和程序性死亡配体-1 (PD-L1)（一种 PD-1 配体） ADPKD。我们发现，1）Pkd1突变肾脏中T细胞上的PD-1表达上调； 2) PD-L1 是 Pkd1 突变肾上皮细胞和组织中表达上调，并且在囊性细胞来源中表达增加 外泌体； 3）Pd-l1的敲除延迟了囊肿的生长并增加了Pkd1敲除小鼠的存活率； 4） 使用抗体靶向 PD1 和 PD-L1 可延迟 Pkd1 敲除肾脏中囊肿的生长； 5) 治疗用 从 ADPKD 患者的囊性肾上皮细胞和尿液中分离的外泌体增加了 Pkd1 野生型 肾上皮细胞增殖，并诱导这些细胞中 PKD 相关信号的激活； 6） 用囊性肾上皮细胞来源的外泌体治疗可促进 Pkd1 突变肾脏中囊肿的生长； 7） 用 ADPKD 尿外泌体处理的肾上皮细胞（NRK-52E 细胞）也出现囊肿样 胶原蛋白凝胶的结构； 8) GW4869 抑制外泌体分泌可延迟 Pkd1 中的囊肿生长 敲除肾脏。我们的中心假设是 PD-L1 对囊性肾上皮细胞的上调和 T 细胞上的 PD-1 通过抑制 T 细胞功能和外泌体导致囊性细胞的免疫逃避 由囊性肾上皮细胞分泌，通过邻近的 T 细胞调节免疫抑制及其功能 其他邻近细胞，包括肾上皮细胞和成纤维细胞，有助于囊肿生长。我们测试 这一假设具有三个具体目标。这项研究将首次确定 PD-1 和 PD-L1 是否 是囊性肾中的免疫抑制剂，有助于囊性上皮细胞逃避免疫攻击 ADPKD，以及囊性上皮细胞分泌的外泌体是否有助于免疫抑制和 其他蜂窝通信。此外，我们将确定PD1和PD-L1是否是有效靶点 临床前环境中减缓疾病进展。完成这项研究将有助于更好地理解 肾囊肿形成中的免疫监视机制以及囊肿细胞外泌体在肾囊肿形成中的作用的研究 调节免疫抑制和其他细胞间通讯，这将提供新的治疗方法 ADPKD 治疗策略。