US-Australia Collaborative Research: Research Planning and proof-of-concept study of macrophage-scaffold interactions

在美国，每年发生600万例骨折，其中5-10%的骨折由于骨丢失、固定失败、感染和血管化不足而无法充分愈合。利用人体的优势，促进骨再生的生物材料的使用？它自身的自然愈合能力将绕过所有与自体移植和同种异体移植相关的问题。开发用于修复和再生承重应用中的大骨缺损的骨科植入物的关键挑战是在材料性能、植入物结构和生物活性之间取得适当的平衡，以满足骨组织的功能和再生要求。澳大利亚悉尼大学的Hala Zreiqat博士和Roohani-Esfahani博士在实现这一目标方面取得了重大进展，他们开发了一种新型多组分陶瓷，这种陶瓷可以在孔隙率（80-95%）、孔径（300- 500 μ m）和独特的机械强度方面模拟骨。这些支架在兔中引起了广泛的新骨形成，并完全桥接了临界尺寸的桡骨缺损。然而，将生物材料植入受损骨中会影响炎症反应细胞的行为，特别是巨噬细胞，从而影响新骨再生。该提案的主要研究重点是巨噬细胞的行为如何决定组织再生。鉴于巨噬细胞和炎症反应对所有组织修复的重要性，这项工作的结果广泛适用于任何组织的工程。此外，该项目将促进美国和澳大利亚工程专业学生和教师之间的跨文化交流。该项目的五名参与者中有三名是女工程师。

In the United States, 6 million bone fractures occur annually, and 5-10% of these fractures fail to heal adequately due to bone loss, failed fixation, infection, and inadequate vascularization. The use of biomaterials that can promote bone regeneration by taking advantage of the body?s own natural healing ability would bypass all of the problems associated with autografts and allografts. The key challenge in developing orthopedic implants for the repair and regeneration of large bone defects in load-bearing applications is to strike the right balance between material properties, implant architecture and bioactivity to satisfy the functional and regenerative requirements of bone tissue. Dr. Hala Zreiqat and Dr. Roohani-Esfahani at the University of Sydney in Australia have made major advances towards achieving this goal through the development of a new multi-component ceramic that can mimic bone in porosity (80-95%), pore diameter (300-500um) and, uniquely, mechanical strength. These scaffolds caused extensive new bone formation with complete bridging of critically sized radial defects in rabbits. However, implantation of biomaterials into injured bone affects the behavior of the cells of the inflammatory response, especially macrophages, with resulting effects on new bone regeneration. The main research focus of this proposal is how the behavior of macrophages dictates tissue regeneration.Given the importance of macrophages and the inflammatory response for the repair of all tissues, the results of this work are broadly applicable for engineering of any tissue. In addition, this project will promote cross-cultural exchange between American and Australian engineering students and faculty. Three of the five participants in this project are women engineers.