Synthetic IL9R signaling to rewire T cells for adoptive cell therapy of cancer

项目总结 使用工程T细胞的过继细胞治疗(ACT)--如嵌合抗原受体(CAR)或T细胞受体 (TCR)修饰的T细胞--是治疗恶性血液病的有效免疫疗法。ACT的成功有 对于实体肿瘤一直难以捉摸，实体肿瘤对T细胞构成了独特的挑战。表演也需要条件反射。 化疗耗尽患者的内源性T细胞，从而导致显著的毒性。我们的目标是 设计具有合成功能的T细胞，以克服实体肿瘤ACT的障碍，包括需要 条件化疗，这将极大地提高这种疗法的可行性和安全性。 在这项建议中，我们使用了由我们的合作者加西亚博士在 斯坦福大学。正交型IL2Rβ(O2R)只能被正交型IL2(O2R)细胞因子激活，而不能被野生型激活 IL2。当被激活时，o2R通过IL2Rβ的胞内区(ICD)发出信号，这涉及到合作 与天然公共伽马链(γc)结合。利用这种合作，我们研究了嵌合正交 受体，其中o2R的IL2RβICD被其他γc细胞因子受体的ICD取代，如OIL 2 引出相应的γc信号。在这些嵌合体中，通过IL9R ICD(O9R)发出的信号产生了一个独特的 STAT磷酸化图谱和分化轨迹，促使体内进一步探索。尽管有一个 增殖信号弱于o2R信号，o9R信号导致T细胞具有更好的抗肿瘤效果， 在没有淋巴耗竭的情况下，这种效果明显。 要将这一发现转化为治疗晚期实体瘤患者的可行方法，将需要 了解O9R信号T细胞的功能特性使其具有抗肿瘤作用，尤其是 在没有条件化疗的情况下。我们的初步数据让我们专注于其中的两个功能， 我们在目标1和目标2中解决了这些问题。在目标1中，我们专注于o9R信号在体内的外周效应，这些信号依赖于 关于与宿主的相互作用，特别是淋巴结归巢和启动。我们假设O9R信号 对外周T细胞进行重新编程，以实现高效的淋巴结归巢和促进启动的空间定位 这对于它们在体内的抗肿瘤作用至关重要。AIM 1将同时使用TCR和CAR同基因小鼠 ACT实体瘤模型。在目标2中，我们转向o9R信号对效应器能力的细胞内在效应。 面对慢性抗原的刺激。我们假设o9R信号干扰了表观遗传变化。 在慢性抗原刺激的背景下，这会导致T细胞功能障碍，从而产生优越的效应器能力。 AIM 2将主要使用人类T细胞，其中含有针对NY-ESO-1抗原的TCR，以及 PMEL模型。 我们互补的目标概述了一种方法来定义IL-9R信号在T细胞中的作用，这是其基础 在没有条件化疗的实体肿瘤中发挥抗肿瘤作用。我们的发现将为 携带IL9R信号的T细胞的治疗性翻译。

PROJECT SUMMARY Adoptive cell therapy (ACT) using engineered T cells – such as chimeric antigen receptor (CAR) or T cell receptor (TCR) modified T cells – is an effective immunotherapy for hematologic malignancies. Success with ACT has been elusive for solid tumors, which present unique challenges to T cells. ACT also requires conditioning chemotherapy to deplete a patient’s endogenous T cells, which results in significant toxicity. Our goal is to engineer T cells with synthetic functions to overcome hurdles of ACT for solid tumors including the need for conditioning chemotherapy, which would dramatically improve the feasibility and safety of this therapy. In this proposal we use the orthogonal IL2 cytokine-receptor pair developed by our collaborator Dr. Garcia at Stanford. Orthogonal IL2Rβ (o2R) is only activated by the orthogonal IL2 (oIL2) cytokine, and not by wildtype IL2. When activated, o2R signals through the intracellular domain (ICD) of IL2Rβ, which involves cooperation with the native common gamma chain (γc). Leveraging this cooperation, we studied chimeric orthogonal receptors in which the IL2Rβ ICD of o2R is replaced with ICDs of receptors for other γc cytokines, such that oIL2 elicits the corresponding γc signal. Of these chimeras, signaling through the IL9R ICD (o9R) generated a unique STAT phosphorylation profile and differentiation trajectory, prompting further exploration in vivo. Despite a weaker proliferative signal than o2R signaling, o9R signaling resulted in T cells with superior anti-tumor efficacy, an effect pronounced in the absence of lymphodepletion. To translate this finding into a viable treatment for patients with advanced solid tumors will require an understanding of the functional features of o9R signaling T cells that permit their anti-tumor efficacy, especially in the absence of conditioning chemotherapy. Our preliminary data led us to focus on two of these features, which we tackle in Aims 1 and 2. In Aim 1, we focus on the peripheral in vivo effects of o9R signaling that rely on interaction with the host, especially lymph node homing and priming. We hypothesize that the o9R signaling reprograms T cells in the periphery for efficient lymph node homing and spatial positioning that promotes priming that is critical for their anti-tumor effects in vivo. Aim 1 will use both TCR- and CAR- based syngeneic mouse solid tumor models of ACT. In Aim 2, we turn to the cell-intrinsic effects of o9R signaling on effector capacity in the face of chronic antigen stimulation. We hypothesize that o9R signaling interferes with the epigenetic changes that drive T cell dysfunction in the context of chronic antigen stimulation, resulting in superior effector capacity. Aim 2 will primarily use human T cells engineered with a TCR specific for the NY-ESO-1 antigen along with the pmel model. Our complementary aims outline an approach to define the effects of IL9R signaling in T cells that underlie their anti-tumor functions in solid tumors without conditioning chemotherapy. Our findings will set the stage for the therapeutic translation of T cells endowed with IL9R signaling.