Glycolysis and Glutaminase in CD8 T cell differentiation and anti-tumor immunity

总结 免疫疗法改变了癌症治疗并改善了临床结果，但它不能治愈大多数癌症。 患者抗PD 1单克隆抗体和嵌合抗原受体（CAR）T细胞等治疗 通过增强癌症特异性产生干扰素γ的Th 1 CD 4 T细胞的活性发挥作用， 细胞毒性CD 8 T细胞（CTL）。然而，效应器功能的增加必须与抗肿瘤能力相平衡。 癌症T细胞长期存在。免疫治疗的一个关键目标是增强效应子功能，同时 维持T细胞寿命和记忆力。从拉斯梅尔实验室的工作中可以清楚地看到，效应T细胞 利用高速率的糖酵解，而记忆细胞利用线粒体途径。在这里，我建议测试细胞 在免疫治疗中，作为增强效应和记忆T细胞群体的手段，可以使用代谢。T细胞 活化后根本改变其代谢，并增加糖酵解和谷氨酰胺氧化 （去乙酰氨基）以支持分化、效应器功能和最终产生长期记忆， 依赖于线粒体。调节T细胞谷氨酰胺代谢可以增强 免疫疗法通过增强T细胞效应器功能或记忆能力。拉斯梅尔实验室已经证明 代谢程序有氧糖酵解是炎症中效应T细胞（Teff）功能所必需的， 在肿瘤中。谷氨酰胺分解补充糖酵解，通过将谷氨酰胺转化为三羧酸 酸循环中间体α-酮戊二酸（aKG）。使用条件性敲除多巴胺分解酶 谷氨酰胺酶（GLS），其将谷氨酰胺转化为谷氨酸，以及目前临床上用于治疗的GLS抑制剂。 作为抗癌剂的试验中，我们发现GLS的抑制导致了GLS的代偿性增加， 糖酵解增强Th 1和CTL Teff功能和分化。除了增加效应器 然而，我发现GLS抑制也增加了抑制性受体的表达， GLS缺陷最终抑制T细胞。相反，短暂的GLS抑制增强Teff功能， 也引发线粒体代谢的记忆样分化，并导致改善T细胞的持久性 in vivo.在这个建议中，我将测试的假设，即短暂的GLS抑制可以增加Teff功能， 维持T细胞存活和记忆以增强抗癌免疫治疗功效，而慢性GLS 抑制将驱动代偿性糖酵解、终末Teff分化和衰竭。我会：（1）测试如何 瞬时与慢性GLS抑制通过确定记忆T细胞形成的差异来影响CTL命运， 评估代偿性糖酵解对Teff表型的贡献，并建立线粒体 （2）测试GLS抑制对免疫治疗功效的影响， 靶向CD 19的CAR T细胞和抗PD 1治疗。这些研究将展示一种新的方法， 改进抗癌免疫疗法并强调使用GLS抑制来调节T细胞的策略 代谢和分化。

Summary Immunotherapy has transformed cancer treatment and improved clinical outcomes, but it does not cure most patients. Treatments such as anti-PD1 monoclonal antibodies and chimeric antigen receptor (CAR) T cells function by boosting the activity of cancer-specific interferon gamma-producing Th1 CD4 T cells and cytotoxic CD8 T cells (CTL). Increased effector function, however, must be balanced with the ability of anti- cancer T cells to persist long-term. A key goal of immunotherapy is to enhance effector function while maintaining T cell longevity and memory. It is now clear from work in the Rathmell lab that effector T cells utilize high rates of glycolysis while memory cells utilize mitochondrial pathways. Here I propose to test cell metabolism as a means to enhance both effector and memory T cell populations in immunotherapy. T cells radically alter their metabolism upon activation and increase glycolysis and glutamine oxidation (glutaminolysis) to support differentiation, effector function, and eventual generation of long-term memory that depend on mitochondria. Modulation of T cell glutamine metabolism may augment the efficacy of immunotherapy by enhancing both T cell effector function or memory capacity. The Rathmell Lab has shown that the metabolic program aerobic glycolysis is essential for effector T cell (Teff) function in inflammation and in tumors. Glutaminolysis complements glycolysis to fuel T cells by converting glutamine to the tricarboxylic acid cycle intermediate alpha-ketoglutarate (aKG). Using a conditional knockout of the glutaminolysis enzyme Glutaminase (GLS), which converts glutamine to glutamate, and an inhibitor of GLS that is currently in clinical trials as an anti-cancer agent, we have found that inhibition of GLS leads to a compensatory increase in glycolysis that enhances Th1 and CTL Teff function and differentiation. In addition to increasing effector function, however, I found that GLS inhibition also increases expression of inhibitory receptors, and chronic GLS deficiency ultimately suppresses T cells. In contrast, transient GLS inhibition enhanced Teff function while also priming mitochondrial metabolism for a memory-like differentiation, and led to improved T cell persistence in vivo. In this proposal, I will test the hypothesis that transient GLS inhibition can augment Teff function and maintain T cell survival and memory to boost anti-cancer immunotherapy efficacy, whereas chronic GLS inhibition will drive compensatory glycolysis, terminal Teff differentiation, and exhaustion. I will: (1) Test how transient versus chronic GLS inhibition affects CTL fate by determining differences in memory T cell formation, assessing the contribution of compensatory glycolysis to Teff phenotypes, and establishing the mitochondrial consequences of GLS inhibition; and (2) Test the effect of GLS inhibition on the immunotherapy efficacy of CD19-targeted CAR T cells and anti-PD1 treatment. These studies will demonstrate a new approach to improve anti-cancer immunotherapy and highlight a strategy of using GLS inhibition to modulate T cell metabolism and differentiation.