Understanding Mechanisms Driving Lung Disease Caused by Environmental Particulate Matter

总的来说，呼吸系统疾病是世界范围内的主要死亡原因。因此，呼吸系统研究增加了500%，动物模型支持了这项研究的大约20%。仅在过去的十年里，就有90多万只小鼠被用来帮助了解人类的呼吸健康，然而，人类和小鼠肺之间的生理和解剖差异使得很难将研究成果转化为人类的疗法。吸入研究的重点是吸入的化学品、颗粒物、细菌、病毒、药物输送系统和污染对健康肺和患病肺的影响。最广泛使用的人类特定的人类肺模型是基于细胞的模型，这些模型侧重于肺上皮细胞，即构成肺表面的细胞。虽然这些模型对模拟上皮对吸入物质的反应是有用的，但整个肺的反应是极其重要的，包括复杂的细胞间相互作用和信号、免疫细胞和细胞外基质修饰，目前只有小鼠模型才能完全复制，因此它们被过度使用。我们将通过创建一个多细胞类型的、免疫活性的人肺泡模型来解决这个空白，该模型不含动物，能够伸展，适用于呼吸系统研究的许多领域。为了实现这一目标，我们将在我们的工业合作伙伴曼彻斯特生物凝胶公司开发的合成水凝胶中使用干细胞来源的II型肺泡上皮细胞与巨噬细胞、成纤维细胞和内皮细胞。我们将演示该模型的应用，以了解世界上最重要的环境污染物--大气颗粒物如何影响肺部健康。以下目标将为“下一代”人类肺泡模型提供机会，该模型能够模拟上皮反应、纤维化以及免疫系统的模型，并可在呼吸系统研究的许多领域提供重要的机制、诊断和治疗信息。1)：将hPSC来源的肺细胞类型结合到合成的无动物水凝胶中。我们将把我们的干细胞来源的II型肺泡上皮细胞与巨噬细胞、成纤维细胞和内皮细胞结合在一个合成水凝胶中，生成一个具有免疫活性的人肺泡三维多细胞类型的器官模型。我们将在不同的水凝胶配方中表征有机类物质的结构，这些水凝胶在有和没有拉力的情况下都能模拟纤维化。然后，我们将把单个细胞的行为与在同等条件下培养的人类精密切割肺切片进行比较和验证。2)了解颗粒物对肺泡组织的影响为了进一步演示模型的应用，我们将在目标1中确定的不同水凝胶和拉伸特性中将肺泡有机物暴露在环境颗粒物中。然后我们将表征每种细胞类型的响应，并使用目标1中的人类精密切割肺切片来比较和验证响应。3)教育和培训新用户开发和操作HiPSC衍生的肺泡有机物质。我们将主办一次会议，重点关注当前人类健康和疾病的无动物模型，以教育当前和未来使用和开发无动物人体健康模型的研究领导者。我们还将为想要采用和使用我们的模型用于自己的研究目的的研究人员举办为期一周的培训课程。这些目标将创建适用于许多不同呼吸道疾病的人类肺泡组织的“下一代”模型，可以减少和取代动物模型。重要的是，将向其他研究人员提供培训机会，使他们能够根据自己的实验需求采用和修改该模型，进一步增加该平台在减少研究中使用动物方面产生积极影响的可能性。

Collectively, respiratory diseases are the leading cause of death worldwide. As a consequence respiratory research has increased by 500% and animal models have supported approximately 20% of this research. More than 900,000 mice have been used in the last decade alone to help understand human respiratory health, however, the physiological and anatomic differences between the human and mouse lungs have made it difficult to translate research findings into human therapies. Inhalation research focuses on the effect of inhaled chemicals, particles, bacteria, viruses, drug delivery systems and pollution in both healthy lung and diseased lungs. The most widely used human specific models of the human lung are cell-based models that focus on lung epithelial cells, the cells that make up the surface of the lungs. While these models are useful to model the response of epithelium to inhaled substances, the whole lung response is extremely important and encompasses complex cell-to-cell interactions and signalling, immune cells and extracellular matrix modifications that currently only mouse models can fully replicate, hence their over-use.We will address this gap in model platforms by creating a multi-cell type, immune competent model of human lung alveoli that is animal-free, capable of stretching and applicable to many areas of respiratory research. To achieve this we will use stem cell derived type II alveoli epithelial cells with macrophages, fibroblasts and endothelial cells in a synthetic hydrogel developed by our industrial partner Manchester BIOGEL. We will demonstrate application of the model to understand how atmospheric particulate matter, the most significant environmental pollutant in the world, affects lung health. The objectives below will provide an opportunity for a "next-generation" model of the human lung alveoli, capable of modelling epithelial response, fibrosis as well as that of the immune system and could provide important mechanistic, diagnostic and therapeutic information across many areas of respiratory research. 1): Combine hIPSC derived lung cell types into synthetic animal-free hydrogels.We will bring together our stem cell derived type II alveoli epithelial cells, with macrophages, fibroblasts and endothelial cells in a synthetic hydrogel to generate a 3D multi-cell-type, immune competent organoid model of the human lung alveoli. We will characterise structure of the organoid in different hydrogel formulations that mimic fibrosis both with and without stretch forces. We will then compare and validate individual cell behaviour to human precision cut lung slices cultured under equivalent conditions. 2) Understand the impact of particulate matter on lung alveoli tissueTo further demonstrate application of the model we will expose the alveoli organoids to environmental particulate matter in different hydrogel and stretch characteristics identified in Obj 1. We will then characterise the response of each cell type and compare and validate the response using human precision cut lung slices as in Obj 1. 3) Educate and train new users in development and manipulation of hIPSC derived alveoli organoids.We will host a conference focussed on current animal free models of human health and disease to educate current and future research leaders in use and development of animal-free models of human health. We will also host a 1-week training course for researchers that would like to adopt and use our model for their own research purposes.Together these objective will create a "next generation" model of human alveoli tissue applicable that could reduce and replace animal models across many different respiratory diseases. Importantly, there will be training opportunities provided to other researchers that will allow them to adopt and modify the model to their own experimental needs, further enhancing the possibility that the platform will have a positive impact in reducing animal use in research.