Lactate transporter MCT1 is required for the high suppressive function of tumor infiltrating regulatory T cells

肿瘤浸润调节性 T 细胞的高抑制功能需要乳酸转运蛋白 MCT1

基本信息

批准号：
10199740
负责人：
McLane Watson
金额：
$ 4.07万
依托单位：
UNIVERSITY OF PITTSBURGH AT PITTSBURGH
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-02-01 至 2021-11-15
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10199740
关键词：
Address Amino Acids Autoimmunity Biological Assay CD4 Positive T Lymphocytes CD8-Positive T-Lymphocytes CD8B1 gene Carbon Cell Differentiation process Cell Line Cell Respiration Cell physiology Cells Cellular Metabolic Process Citric Acid Cycle Clonal Expansion Colorectal Cancer Communication Data Environment Eragrostis Exhibits FOXP3 gene Genus Hippocampus Glucose Glycolysis Homeostasis Hypoxia Immune In Vitro Interferon Type II Isotopes Knock-out Knowledge Lactate Transporter Lactic acid Link Lymphoid Tissue Malignant Neoplasms Measures Melanoma Cell Metabolic Metabolism Methods Modeling Mus Patients Peripheral Phenotype Positioning Attribute Postdoctoral Fellow Production Propionates Regulatory T-Lymphocyte Research Research Personnel Role Shapes T cell differentiation Testing Training Tumor Immunity Tumor-infiltrating immune cells Volatile Fatty Acids cancer immunotherapy conditioning cytotoxic effector T cell feeding genetic signature glucose uptake gut microbiota improved knock-down melanoma metabolic profile migration neoplastic cell prevent programmed cell death protein 1 recruit resistance mechanism skills success systemic autoimmunity therapy design transcription factor tumor tumor growth tumor metabolism tumor microenvironment tumor progression

项目摘要

Lactate transporter MCT1 is required for the high suppressive function of tumor infiltrating regulatory T cells Abstract Cancer immunotherapy has revolutionized the way we treat cancer, but most patients fail to respond due to several resistance mechanisms including the recruitment, proliferation, and differentiation of regulatory T (Treg) cells in the tumor microenvironment (TME). While cytotoxic effector T (Teff) cells are rendered dysfunctional by the TME, the natural immunosuppressive function of Treg cells remains intact. Treg and Teff cells exhibit distinct metabolisms which may explain the discrepancy in their function within the TME. Metabolically, the TME is characterized by hypoxia, low pH, and limiting metabolites such as glucose and amino acids. While the highly glycolytic Teff cells are in direct competition with the tumor for glucose, recent evidence suggests Foxp3, the lineage defining transcription factor of Treg cells, can reprogram metabolism of Treg cells to function in high lactate, low glucose environments. Hypothesizing that Treg cells were supported by lactic acid within the TME, we bred a mouse with a Treg specific deletion of the lactate transporter MCT1 (Slc16a1f/f Foxp3YFPCre) and inoculated them with B16 melanoma. Treg specific loss of MCT1 resulted in slowed tumor growth and increased survival without leading to systemic autoimmunity. Measuring lactic acid concentration, we observed high levels within B16 tumors relative to peripheral lymphoid tissues. While MCT1 is predominantly recognized to transport lactate, it has several other substrates, such as propionate and studies on colonic Treg cells suggest propionate enhances Treg cell function and differentiation. Preliminary data from our lab corroborate these results, showing Treg cells conditioned in propionate increased expression of Treg markers Nrp1 and Helios. However, from these observations two questions arise, 1) is MCT1 required for Treg cell function only in lactate high TMEs, and 2) how do non-lactate MCT1 substrates influence Treg cell metabolism? We hypothesize that MCT1 is required for intratumoral Treg cell function in lactate rich TMEs and that its substrates promote an oxidative metabolism and the expression of Treg cell signature genes. To address this hypothesis, first we will (1) determine the requirement of MCT1 for intratumoral Treg cell function in metabolically distinct TMEs. We will inoculate Slc16a1f/f Foxp3YFPCre mice with metabolically distinct melanoma cell lines and measure the impact on intratumoral Treg cell metabolism via Seahorse, and function via suppression assay. Second, we will (2) determine the impact of non-lactate MCT1 substrate propionate on Treg cell metabolism. Using Foxp3YFPCre mice we will isolate Treg cells then condition them in media containing propionate and measure the impact on metabolism via Seahorse and apply isotopic flux analysis to identifying how Treg cells utilize propionate. By understanding the role of MCT1 and its substrates for Treg cell metabolism and function we can better design therapies that specifically dampen intratumoral Treg cells and improve cancer immunotherapies. This training will prepare me for an academic post-doctoral and ultimately independent investigator position by enhancing my research and communication skills and deepening my knowledge of Treg cells in cancer.

乳酸转运蛋白MCT1是肿瘤浸润调节T细胞的高抑制作用所必需的抽象的癌症免疫疗法彻底改变了我们治疗癌症的方式，但大多数患者无法做出应有的反应到几种电阻机制，包括调节t的募集，增殖和分化（Treg）肿瘤微环境（TME）中的细胞。而细胞毒性效应t（teff）细胞通过 TME Treg细胞的自然免疫抑制功能保持完整。 Treg和Teff细胞表现出不同的可以解释其功能中TME的差异的代谢。代谢，TME是以缺氧，低pH值和限制代谢物（如葡萄糖和氨基酸）为特征。而高度最近的证据表明，糖酵解的Teff细胞与葡萄糖的肿瘤直接竞争，表明Foxp3，定义Treg细胞转录因子的谱系可以重新编程Treg细胞的代谢，以在高乳酸中起作用，低葡萄糖环境。假设Treg细胞在TME内得到乳酸支持，我们繁殖了具有乳酸转运蛋白MCT1（SLC16A1F/F FOXFPCRE）的Treg特异性缺失的小鼠并接种他们患有B16黑色素瘤。 Treg的特异性MCT1损失导致肿瘤生长减慢和生存增加没有导致系统性自身免疫性。测量乳酸浓度，我们观察到高水平 B16肿瘤相对于周围淋巴组织。虽然MCT1主要被认为可以运输乳酸，但它还有其他几个底物，例如丙酸和对结肠Treg细胞的研究表明丙酸酯增强 Treg细胞功能和分化。我们实验室的初步数据证实了这些结果，显示了Treg细胞以丙酸酯为条件增加了Treg标记NRP1和HELIOS的表达。但是，从这些观察出现了两个问题，1）仅在乳酸高TME中需要Treg细胞功能MCT1，以及2）如何非乳酸MCT1底物会影响Treg细胞代谢吗？我们假设MCT1是必需的富含乳酸的TME中的肿瘤内Treg细胞功能，其底物促进氧化代谢和Treg细胞特征基因的表达。为了解决这一假设，首先我们将（1）确定MCT1对代谢不同TME中肿瘤内Treg细胞功能的需求。我们将接种slc16a1f/f foxp3yfpcre小鼠具有代谢不同的黑色素瘤细胞系并测量撞击在肿瘤内Treg细胞中通过海马代谢，并通过抑制测定功能。第二，我们将（2）确定非乳酸MCT1底物丙酸对Treg细胞代谢的影响。使用foxp3yfpcre 小鼠我们将隔离treg细胞，然后在含有丙酸酯的培养基中调节它们，并测量对通过海马代谢，并应用同位素通量分析以识别Treg细胞如何利用丙酸酯。经过了解MCT1及其底物对Treg细胞代谢和功能的作用，我们可以更好地设计专门抑制肿瘤内Treg细胞并改善癌症免疫疗法的疗法。这个培训将通过增强我研究和沟通技巧，加深我对癌症中Treg细胞的了解。