Development of vessel-on-chip device to study mechanisms of deep vein thrombosis

深静脉血栓形成(DVT)是一种危及生命的疾病，死亡率超过乳腺癌、艾滋病毒和交通事故的总和。目前研究深静脉血栓形成机制的方法在很大程度上是建立在动物模型的基础上的，因此，发展包括整个复杂因素的体外方法来研究这种疾病是及时和非常可取的。DVT发生在静脉内的一个特殊位置：瓣膜腔，这是一个具有非常特殊的血液流动几何形状的区域，在那里总的血流速度会显著降低。这会导致血管壁的炎症样变化，导致血栓形成。现有的大多数流动室/微流控装置要么根本没有阀门，要么有带有固定固定小叶的阀门。我们最近开发了一种独特的微流体室，其中包含灵活的瓣叶，它允许完全重现人类的静脉血流动力学。此外，我们还能够开发出一种在这种腔体的表面覆盖人类内皮的方法。在拟议的项目中，我们计划继续这一研究方向，并通过在细胞培养中加入平滑肌细胞、肥大细胞、成纤维细胞和细胞外基质蛋白来进一步模拟血管壁的复杂性。特别是，基于我们之前的研究(Schofield等人)。Commun Mater 2020；Baksamawi等人。我们将与医疗技术研究所(Healthcare Technologies Institute，第二主管Liam Grover教授)合作，追求以下目标：开发一种包括微流体室内静脉壁主要成分的多细胞培养，并将其与动物研究中已公布的数据进行比较，验证该模型。确定每种血管壁细胞类型在DVT中的作用。探索/验证主要抗血栓药物的效果。因此，我们将创建一个完整的“芯片上血管”模型，并用它来探索DVT的启动机制。该模型将具有以下优势：1)表示人体静脉模型，根据定义，它消除了由动物和人类之间的差异引起的问题2)比任何动物模型更标准化、更具重复性和更便宜4)技术简单，并允许测试多个因素5)允许与所有细胞组件进行简单快速的基因操作以评估单独基因的影响6)允许检测患者的血液，这在动物模型中无法实现7)可能是预测患者DVT可能性的有用的临床工具8)不需要内政部的伦理批准。

Deep vein thrombosis (DVT) is a life-threatening disease with mortality exceeding that from breast cancer, HIV, and traffic accidents, combined. Current methods to study mechanisms of DVT are heavily based on animal models and, therefore, development of in vitro approaches that would include the entire complexity of factors to study the disease is timely and highly desirable. DVT develops in a special location inside the veins: valve pockets, a region with a very specific blood flow geometry, where overall flow rate is strongly reduced. This results in inflammation-like changes in the vessel wall leading to thrombosis. Most of the existing flow chamber/microfluidic devices either don't have valves at all or have valves with fixed immobile leaflets. We have recently developed a unique microfluidic chamber containing flexible valve leaflets, which allows for full recapitulation of venous hemodynamics in humans. Moreover, we were able to develop a method to coat the surface of such chamber with human endothelium. In the proposed project, we plan to continue this research direction and further mimic the complexity of the vessel wall by including smooth muscle cells, mast cells, fibroblasts, and extracellular matrix proteins, into cell culture. In particular, based upon our previous studies (Schofield et al. Commun Mater 2020; Baksamawi et al. Front Cardiovasc Med 2023) and in collaboration with the Healthcare Technologies Institute (Prof. Liam Grover, the second supervisor), we will pursue the following objectives:To develop a multi-cell culture including major components of the venous wall inside the microfluidic chamber, and validate the model comparing it to published data obtained in animal-based research.Determine the role of each vessel wall cell type in DVT.Explore/verify the effects of major antithrombotic drugs.As a result, we will create a complete "vessel-on-chip" model and use it to explore mechanisms of DVT initiation. The model will have the following advantages: 1) represent a model of human vein, which by definition removes issues originating from differences between animals and humans 2) better standardized, more reproducible and cheaper than any animal model 4) technically simple and allows for testing of multiple factors 5) allows for easy and fast genetic manipulations with all cellular components to evaluate the impact of separate genes 6) allows for testing blood of patients, which cannot be implemented in animal models 7) may represent a useful clinical tool for predicting the likelihood of DVT in patients 8) does not require Home Office ethical approval.