DurImplant - Analysis of implant behavior after bioreactor maturation in vitro

P05项目的目的是开发一种体外方法，用于研究生物杂交种植体的耐久性，重点是钙化倾向作为植入体寿命和功能的决定性限制因素。钙化倾向及其预测和预防已成为生物瓣膜研究的重要课题。为了解决这个问题，我们提出了一个假设，即具有重要的、功能活跃的内皮细胞的生物杂交型心脏瓣膜假体是钙化的天然屏障。我们将在尽可能接近现实的仿生测试环境中测试这一假设。CVE已经有了一套动态耐久性测试系统，用于测试AVITAL生物人工心脏瓣膜，但这是基于纯粹的机械和物理化学基础上的，因此无论从生理还是从细胞毒理学的角度来看，都不能为细胞化材料提供合适的测试环境。在第一个项目阶段，开发了与细胞相容的流体以及关于pH、温度和流动条件的生理测试环境，这也允许在线检测生物杂化植入物上新出现的钙化。在第二个项目阶段，第一个项目阶段已经开发的流动室将进一步扩大和增强细胞分析。这将使在小范围内评估种植体的稳定性和钙化趋势成为可能。为此，已经建立的胎球蛋白-A成像将进一步改进，以便能够对钙化做出定量声明。此外，还将分析细胞的健康状况以及生物杂交植入物的内皮化情况。从细胞分析中获得的知识将用于改进测试。这将为项目合作伙伴提供有关所开发植入物行为的直接反馈，以及这些植入物顶部的细胞。在进一步开发流室测试系统的同时，还在开发全尺寸生物混合植入物测试系统。这将允许在与体内情况相似的无菌环境中测试完整的全尺寸植入物的疲劳强度和钙化倾向。植入物在无菌条件下安装在实验室中，并填充测试室。此外，测试系统还将进一步开发，以允许对植入物进行在线成像和连续分析。

The aim of project P05 is the development of an in vitro methodology for the investigation of the durability of biohybrid implants with focus on the propensity to calcification as a decisive limiting factor of the implant lifetime and function. The issue of calcification propensity and its prediction and prevention is already of great importance in avital bioprosthetic heart valves. Addressing this issue, we pose the hypothesis that biohybrid heart valve prostheses with a vital, functionally active endothelium are a natural barrier for calcification. We will test this hypothesis in a biomimetic test environment as close to reality as possible. CVE already has a dynamic durability test system for testing avital bioprosthetic heart valves, which is however premised on a purely mechanical and physicochemical basis, and therefore does not offer a suitable test environment for cellularized material, neither from a physiological nor cytotoxicological point of view. In the first project phase, cell-compatible fluids as well as a physiological test environment with regard to pH, temperature and flow conditions were developed, which also allows the online detection of emerging calcifications on biohybrid implants.In the second project phase, the flow chamber already developed in the first project phase will be further expanded and enhanced with cell assays. This will make it possible to assess implant stability and calcification tendency on a small scale. For that, the already established Fetuin-A-imaging will be further refined in order to be able to make quantitative statements on calcification. In addition, the health of the cells as well as the endotheliazation of the biohybrid implants will be analyzed. The knowledge gained from the cell analyses will be used to improve the testing. This will provide the project partners with direct feedback on the behavior of the developed implants as well as cells on top of these implants. In parallel with the further development of the flow chamber test system, a test system for full-size biohybrid implants is also being developed. This will allow testing of fatigue strength and calcification tendency of complete, full-size implants in a sterile environment with conditions similar to the in vivo situation. Implants are installed in the laboratory under sterile conditions and the test chamber is filled. Furthermore, the test system will be further developed to also allow online imaging and continuous analysis of the implant.