Multi-organ culture and pumping systems for ex vivo models of immunity in hybrid tissue-chips

用于混合组织芯片中的离体免疫模型的多器官培养和泵送系统 更好地了解淋巴结（LN）和器官之间的细胞和分子通讯， 排水系统对公众健康至关重要。这些事件决定了我们对抗感染和应对 疫苗，新生肿瘤是否被识别和摧毁，以及我们自己的组织是否仍然安全， 自身免疫然而，淋巴结与外周器官的动态相互作用一直是困难的 在体内或体外进行研究，难以预测免疫反应，了解疾病机制，或 设计疫苗和免疫疗法。在这里，我们将开发一个微流控培养和泵送系统 专门设计用于模拟淋巴结和周围器官之间的通信，以模拟多- 组织免疫该模型将建立在我们先前建立的用于两种细胞共培养的微流体系统的基础上。 在培养基的再循环下的切片，这在捕获肿瘤诱导的 淋巴结的免疫抑制（Shim，Lab Chip 2019）。我们将在此基础上创建第一个 组织切片共培养系统，专门设计用于免疫学家和其他生物医学 研究人员在易于使用的精确流量控制和组织之间的白色血细胞循环方面。 首先，我们将开发一系列3D打印的多器官微型设备，用于在3D打印条件下培养完整的组织切片。 横向或侧向灌注，有或没有空气/液体界面（例如，用于脑和皮肤切片），以及支持 白色血细胞通过多个组织的再循环。同时，我们将改进流体控制系统， 强大且用户友好的多切片共培养和淋巴细胞再循环，可扩展至数十个切片 cultures.我们将从我们最近的原型片上基于磁力叶轮的泵开始，该泵与 细胞培养箱和细胞再循环（Cook，Lab Chip 2022）。结合先进的流体动力学 模拟与实验测试，我们将简化泵，以减少死体积，确保一致性， 流动控制和保持循环白色血细胞的活力。其他实验室的用户测试将进一步 完善设计。利用现有的流量控制，我们将测试淋巴结组织 功能对液体流速敏感，并确定多器官淋巴结培养的最佳流动模式。 最后，我们将利用我们强大的团队在疫苗免疫学方面的专业知识， 引流和淋巴结对疫苗接种的反应，作为系统的原理证明。最终 这里开发的用户友好的多器官免疫功能模型平台将使生物医学研究 更好地预测对疫苗接种和免疫治疗的反应，肿瘤免疫的发生， 在自身免疫过程中，脑、肠或关节炎关节与淋巴结的接合。

Multi-organ culture and pumping systems for ex vivo models of immunity in hybrid tissue-chips A better understanding of cellular and molecular communication between the lymph node (LN) and the organs it drains is imperative for public health. These events determine how well we fight infections and respond to vaccines, whether a nascent tumor is recognized and destroyed, and whether our own tissues remain safe from autoimmunity. However, the dynamic interactions of the lymph node with peripheral organs have been difficult to study in vivo or in vitro, making it difficult to predict immune responses, understand disease mechanisms, or design vaccines and immunotherapies. Here, we will develop a microfluidic culture and pumping system specifically designed to model communication between the lymph node and surrounding organs, to model multi- tissue immunity. This model will build on our prior establishment of a microfluidic system for co-culture of two slices under a recirculating loop of media, which showed promise in capturing tumor-induced immunosuppression of the lymph node (Shim, Lab Chip 2019). We will build on this concept to create the first tissue slice co-culture system that is specifically designed for use by immunologists and other biomedical researchers in terms of ease of use for precise flow control and circulation of white blood cells between tissues. First, we will develop a series of 3D printed multi-organ microdevices for culture of intact tissue slices under transverse or lateral perfusion, with or without an air/liquid interface (e.g. for brain and skin slices), and supporting recirculation of white blood cells through multiple tissues. In parallel, we will refine the fluidic control system for robust and user-friendly multi-slice co-cocultures and lymphocyte recirculation, with scale up to dozens of slice cultures. We will start from our recent prototype on-chip magnetic impeller-based pump, which is compatible with cell culture incubators and cell recirculation (Cook, Lab Chip 2022). Combining advanced fluid dynamic simulations with experimental tests, we will miniaturize the pump to reduce dead volume, ensure consistency of flow control, and preserve viability of circulating white blood cells. User tests in other laboratories will further refine the design. Making use of the available flow control, we will test the hypothesis that lymph node tissue function is sensitive to fluid flow rate, and determine the optimal flow mode for multi-organ lymph node culture. Finally, we will build on our strong team’s expertise in vaccine immunology to generate a simple model of vaccine drainage and response of the lymph node to vaccination, as a proof-of-principle for the system. Ultimately, the user-friendly platform developed here to model multi-organ immune function will enable the biomedical research community to better predict the response to vaccination and immunotherapy, onset of tumor immunity, and engagement of brain, gut, or arthritic joints with the lymph node during autoimmunity.