Department of Orthopaedic Surgery, National University of Singapore, Singapore.
Tissue Eng Part A. 2010 Apr;16(4):1123-41. doi: 10.1089/ten.TEA.2009.0471.
Conventional clinical therapies are unable to resolve osteochondral defects adequately; hence, tissue engineering solutions are sought to address the challenge. A biphasic implant that was seeded with mesenchymal stem cells (MSCs) and coupled with an electrospun membrane was evaluated as an alternative. This dual phase construct comprised of a polycaprolactone (PCL) cartilage scaffold and a PCL-tricalcium phosphate osseous matrix. Autologous MSCs were seeded into the entire implant via fibrin and the construct was inserted into critically sized osteochondral defects located at the medial condyle and patellar groove of pigs. The defect was resurfaced with a PCL-collagen electrospun mesh, which served as a substitute for periosteal flap in preventing cell leakage. Controls without either implanted MSCs or resurfacing membrane were included. After 6 months, cartilaginous repair was observed with a low occurrence of fibrocartilage at the medial condyle. Osteochondral repair was promoted and host cartilage degeneration was arrested as shown by superior glycosaminoglycan maintenance. This positive morphological outcome was supported by a higher relative Young's modulus, which indicated functional cartilage restoration. Bone ingrowth and remodeling occurred in all groups, with a higher degree of mineralization in the experimental group. Tissue repair was compromised in the absence of the implanted cells or the resurfacing membrane. Moreover, healing was inferior at the patellar groove when compared with the medial condyle and this was attributed to the native biomechanical features.
传统的临床疗法无法充分解决骨软骨缺损问题；因此，人们寻求组织工程解决方案来应对这一挑战。一种双相植入物，其中接种了间充质干细胞（MSCs）并结合了电纺膜，被评估为一种替代方法。这种双相结构由聚己内酯（PCL）软骨支架和 PCL-磷酸三钙骨基质组成。通过纤维蛋白将自体 MSCs 接种到整个植入物中，然后将构建体插入位于猪的内侧髁和髌骨沟的临界大小的骨软骨缺损处。用 PCL-胶原电纺网覆盖缺陷部位，该网可替代骨膜瓣，防止细胞渗漏。包括没有植入 MSC 或覆盖膜的对照。6 个月后，在内侧髁处观察到软骨修复，纤维软骨的发生率较低。促进了骨软骨修复，并通过保持较高的糖胺聚糖维持来阻止宿主软骨退化。这种积极的形态学结果得到了相对较高的杨氏模量的支持，表明功能软骨得到了恢复。所有组均发生了骨内生长和重塑，实验组的矿化程度更高。在没有植入细胞或覆盖膜的情况下，组织修复受到损害。此外，与内侧髁相比，髌骨沟处的愈合情况较差，这归因于其固有生物力学特征。
