Regeneration of nasal and articular cartilage with collagen scaffolds from decellularised cartilage

由于软骨再生能力有限，鼻和关节软骨缺损的治疗仍然是一个主要的治疗挑战。目前的治疗方案包括应用自体细胞和组织进行重建。可获得性有限、供体部位发病率以及再生组织的整合度和质量不足是当前技术的主要缺点。一种有希望的替代方案是使用异种来源的脱细胞基质，这种基质提供软骨特有的结构成分和生物活性因子。在这个项目中，我们计划研究猪鼻中隔软骨(NDECM)脱细胞基质在有和没有生长因子增强的情况下是否能够实现局部软骨前体细胞的原位募集和软骨分化，以再生软骨缺损。最近，我们开发了一种生产nDECM的新工艺。这一化学过程维持了天然的胶原蛋白网络，同时可靠地去除了细胞成分。因此，这种材料在体内只会引起最小的刺激性反应。此外，我们还能够在鼻骨和关节软骨中鉴定出具有迁移活性的软骨生成前体细胞(CPC)，它们都具有在体外重新填充nDECM的能力。因此，我们的目标是在生化分析的帮助下，研究脱细胞过程后哪些功能活性成分仍然存在，哪些成分被修饰。然后，将建立将生长因子附着到nDECM上的程序，并将测量分布、释放和吸附动力学。进一步，我们将研究在nDECM中加入生长因子是否会促进CPC和骨髓间充质干细胞的附着和迁移以及向软骨细胞的分化。将分析nDECM对巨噬细胞依赖的炎症反应和蛋白分解基质降解的影响。最后，关于移植到临床，nDECM在鼻骨和关节软骨修复的模型中进行了测试。为此，将采用兔鼻软骨和关节软骨骨软骨缺损的原位模型，移植含有和不含生长因子的nDECM。综上所述，本项目结合了耳鼻咽喉科、骨科和生物过程工程学的专家，在良好的体外和体内分析的基础上建立了一种新的软骨修复治疗方法。

The treatment of cartilage defects of the nose and joints is, due to the limited regeneration capacity of cartilage, still a major therapeutic challenge. Current treatment options include the application of autologous cells and tissues for reconstruction. Limited availability, donor site morbidity as well as insufficient integration and quality of the regenerated tissue are major drawbacks of the current techniques. A promising alternative is the use of decellularised matrices of xenogenic origin, which provide cartilage-specific structural components as well as biologically active factors. Within this project we plan to investigate whether decellularised cartilage matrices from porcine nasal septal cartilage (nDECM) with and without growthfactor augmentation can enable in-situ recruitment and chondrogenic differentiation of local chondrogenic progenitor cells in order to regenerate cartilage defects. Recently, we developed a novel process for the production of nDECM. This chemical process maintains the natural collagen network while at the same time removing cellular components reliably. Therefore, the material evokes only minimally irritating reactions in-vivo. Also, we were able to identify migratory active chondrogenic progenitor cells (CPC) in nasal as well as in articular cartilage, which both had the capacity to repopulate nDECM in-vitro. We therefore aim to investigate with the help of biochemical analyses which functionally active components remain after the decellularisation process and which components are modified. Afterwards, a procedure to attach growth factors to the nDECM will be established, distribution, release and adsorption kinetics will be measured. Further, we will investigate whether attachment and migration as well as chondrogenic differentiation of CPC and bone marrow derived mesenchymal stem cells are enhanced by augmentation of the nDECM with growth factors. The influence of nDECM on macrophage-dependent inflammatory reactions and proteolytic matrix degradation will be analysed. Finally, with respect to translation to the clinic, nDECM is tested in models of nasal and joint cartilage repair. For this purpose orthotopic models of nasal cartilage defects and articular cartilage osteochondral defects in the rabbit will be used in which nDECM with and without growthfactor augmentation will be transplanted. In summary, the current project combines expertises from otorhinolaryngology, orthopedics and bioprocess engineering to establish a novel therapeutic approach for cartilage repair based on sound in-vitro and in-vivo analyses.