Redesigning the T cell: Using Synthetic Biology to Engineer Therapeutic Cells

描述(申请人提供)：工程细胞具有作为强大的“智能”治疗剂的潜力，但我们缺乏工程细胞的系统框架来优化其疗效并将其不良影响降至最低。例如，表达人工肿瘤导向受体(嵌合抗原受体-CARS)的T细胞在治疗某些白血病方面取得了意想不到的成功。但工程细胞缺乏天然T细胞的精确度和可控性：非靶点细胞杀伤以及免疫系统的过度激活会导致大多数患者出现严重的不良反应。实现对这些工程T细胞的控制仍然是一个重大挑战，要使这种疗法成为一种安全可靠的疗法，可以推广到更广泛的疾病。我们建议应用合成生物学的方法来系统地设计治疗性免疫细胞，使其具有更定制和更精确控制的行为。我们将应用我们对细胞信号的知识来设计模块化开关和电路，这些开关和电路可以用来控制这些治疗性细胞。我们的项目将跨越两个互补的方法，表现为以下目标：目标1.开发用于CAR T细胞精确控制的电路模块工具箱。我们将构建可以与CARS结合的模块，以提高它们的特异性和安全性，包括：a.通过小分子或光远程控制T细胞。为医生提供安全开关，以控制移植的治疗细胞的活动。B.可调反馈电路。通过调整剂量-反应阈值、动力学校对和反应幅度/持续时间来优化CAR T细胞反应。C.多抗原触发激活。加大对癌细胞靶向的甄别。D.用户引导的细胞迁移。将T细胞定位于特定的作用部位，提高了精确度。E. 人工合成的细胞间通讯。工程师自分泌和多细胞决策电路。目标2.重构T细胞：确定T细胞反应网络中可用于构建定制反应程序的子模块。目前的CARS复制了T细胞激活的原生程序，但对新的输入做出了反应。我们假设，有许多替代方法可以插入T细胞信令网络并生成定制的响应。我们将扫描重新连接的T细胞信号蛋白的组合库，以确定可通过诱导复杂组装(光或药物)激活的替代控制点。这种网络重布线文库应该揭示可用作构建定制响应程序的构建块的模块化的子网络，包括：a.对以下各项的单独的可诱导的控制：i)T细胞增殖，ii)肿瘤细胞杀伤，以及iii)记忆细胞的建立b.诱导用于癌症治疗的替代细胞因子反应程序(例如，诱导Th1计划)c.诱导针对癌症治疗优化的定制的“点菜”杂交细胞因子反应程序。

DESCRIPTION (provided by applicant): Engineered cells have the potential to serve as powerful "smart" therapeutic agents, but we lack a systematic framework for engineering cells to optimize their efficacy and minimize their adverse effects. For example, T cells expressing artificial tumor-directed receptors (Chimeric Antigen Receptors - CARs) have achieved unexpected success in treating certain leukemias. But the engineered cells lack the precision and control of native T cells: off-target cell killing as well as hyperactivation of the immune system lead to severe adverse effects in most patients. Achieving control over these engineered T cells remains a major challenge to making this a safe and reliable therapy that can be extended to a wider range of diseases. We propose to apply the approaches of synthetic biology to systematically engineer therapeutic immune cells with far more tailored and precisely controlled behaviors. We will apply our knowledge of cell signaling to engineer modular switches and circuits that can be used to control these therapeutic cells. Our project will span two complementary approaches, represented by the following aims: Aim 1. Develop toolbox of circuit modules for precision control of CAR T cells. We will construct modules that can be combined with CARs to increase their specificity and safety, including: a. Remote control of T cells via small molecules or light. Provide physicians with safety switches for controlling activiy of transplanted therapeutic cells. b. Tunable feedback circuits. Optimize CAR T cell responses by tuning dose-response thresholds, kinetic proofreading, and the amplitude/duration of response. c. Multi-antigen triggered activation. Increase discrimination of cancer cell targeting. d. User-guided cell migration. Target T cells to specific sites of action, increasing precision. e. Synthetic cell-cell communication. Engineer autocrine and multi-cell decision-making circuits. Aim 2. Refactoring T cells: identify submodules in the T cell response network that can be used to construct custom response programs. Current CARs replicate the native program of T cell activation, but in response to a novel input. We postulate that there are many alternative ways to plug into the T cell signaling network and to generate custom tailored responses. We will scan combinatorial libraries of rewired T cell signaling proteins to identify alternative control points that can be activated through induced complex assembly (light or drugs). This network-rewiring library should reveal modular subnetworks that can be used as building blocks to construct custom response programs, including: a. Separate inducible control of: i) T cell proliferation, ii) tumor cell killing, and iii) memory cell establishment b. Induction of alternatie cytokine response programs ideal for cancer treatment (e.g. induce Th1 program) c. Induction of custom "a la carte" hybrid cytokine response programs that are optimized for cancer treatment.