Development of a novel biomaterial model of collagen mediated genetic disease for study of collagen organisation and drug development

成骨不全（OI）是一组17种遗传性结缔组织疾病，由胶原基因突变介导，导致骨变形和脆性。目前，体内测试是治疗的标准实践，有超过20种动物模型代表OI。这些模型在技术上是有限的，但也涉及胶原蛋白排列和组织的可访问性和再现性。骨髓间充质干细胞（MSC）可以分化为骨形成细胞，并产生骨样胶原细胞外基质。Reilly教授小组的工作表明，胶原蛋白的组织和质量可以以组织特异性的方式建模。我们提出，导致OI的基因突变也会影响细胞正确组织胶原蛋白的能力，使用这种支架细胞系统将为OI的发病机制提供重要的见解。该项目的目的是开发特征化和验证的OI胶原病理学体外模型。这将通过使用电纺丝来生产聚己内酯支架来实现，细胞将按照既定的方案在该支架上生长。支架纤维特性和胶原结构之间的关系将使用光学显微镜和SEM进行支架特性的映射，并使用组织学和二次谐波发生显微镜进行细胞和细胞外因子的映射。机械试验将用于确定胶原组织在组织结构中的作用。从患者群体中鉴定的OI突变将使用CRISPR内源性基因编辑引入MSC细胞，从而能够比较健康与OI胶原蛋白。这将允许研究分子途径和测试治疗剂。将开发使用ImageJ的高通量图像分析协议，用于大型数据集的系统分析。

Osteogenesis imperfecta (OI) is a group of 17 inherited connective tissue disorders mediated by mutations in collagen genes that lead to bone deformation and fragility. Currently, in vivo testing is the standard practice for treatments, with over 20 animal models representing OI. These models are technically limited, but also with regards to accessibility and reproducibility of collagen alignment and organisation. A validated in vitro method would allow for accurate preclinical modelling.Mesenchymal stem cells (MSC) can differentiate into bone forming cells and create a bone-like collagen extracellular matrix. Work in Prof. Reilly's group has demonstrated that the organisation and quality of the collagen can be modelled in a tissue specific manner. We propose that the genetic mutations that cause OI will also affect the ability of cells to organise collagen correctly, and that using this scaffold-cell system will provide important insight into OI pathogenesis. The aim of this project is to develop characterised and validated in vitro model of OI collagen pathology. This will be achieved by using electo-spinning to produce polycaprolactone scaffolds on which cells will be grown following established protocols. The relationship between scaffold fibre characteristics and collagen structure will be mapped using light microscopy and SEM for scaffold characteristics, and histology and second harmonic generation microscopy for cellular and extracellular factors. Mechanical testing will be used to determine the role of collagen organisation in tissue structure. OI mutations identified from patient populations will be introduced to MSC cells using CRISPR endogenous gene editing enabling comparison between healthy vs OI collagen. This will allow for investigation of the molecular pathways and testing of therapeutic agents. A high throughput image analysis protocol using ImageJ will be developed for systematic analysis of large data sets.