Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, QLD 4059, Australia.
J Biomater Appl. 2013 May;27(8):979-89. doi: 10.1177/0885328211431310. Epub 2012 Jun 8.
The repair of articular cartilage typically involves the repair of cartilage-subchondral bone tissue defects. Although various bioactive materials have been used to repair bone defects, how these bioactive materials in subchondral bone defects influence the repair of autologous cartilage transplant remains unclear. The aim of this study was to investigate the effects of different subchondral biomaterial scaffolds on the repair of autologous cartilage transplant in a sheep model. Cylindrical cartilage-subchondral bone defects were created in the right femoral knee joint of each sheep. The subchondral bone defects were implanted with hydroxyapatite-β-tricalcium phosphate (HA-TCP), poly lactic-glycolic acid (PLGA)-HA-TCP dual-layered composite scaffolds (PLGA/HA-TCP scaffolds), or autologous bone chips. The autologous cartilage layer was placed on top of the subchondral materials. After 3 months, the effect of different subchondral scaffolds on the repair of autologous cartilage transplant was systematically studied by investigating the mechanical strength, structural integration, and histological responses. The results showed that the transplanted cartilage layer supported by HA-TCP scaffolds had better structural integration and higher mechanical strength than that supported by PLGA/HA-TCP scaffolds. Furthermore, HA-TCP-supported cartilage showed higher expression of acid mucosubstances and glycol-amino-glycan contents than that supported by PLGA/HA-TCP scaffolds. Our results suggested that the physicochemical properties, including the inherent mechanical strength and material chemistry of the scaffolds, play important roles in influencing the repair of autologous cartilage transplants. The study may provide useful information for the design and selection of proper subchondral biomaterials to support the repair of both subchondral bone and cartilage defects.
关节软骨的修复通常涉及软骨-软骨下骨组织缺损的修复。尽管已经使用了各种生物活性材料来修复骨缺损，但这些生物活性材料在软骨下骨缺损中如何影响自体软骨移植的修复仍然不清楚。本研究旨在探讨不同软骨下生物材料支架对羊模型自体软骨移植修复的影响。在每只羊的右膝关节股骨髁上创建圆柱形软骨-软骨下骨缺损。将软骨下骨缺损植入羟基磷灰石-β-磷酸三钙（HA-TCP）、聚乳酸-羟基乙酸（PLGA）-HA-TCP 双层复合支架（PLGA/HA-TCP 支架）或自体骨屑。将自体软骨层放置在软骨下材料的顶部。3 个月后，通过研究机械强度、结构整合和组织学反应，系统研究了不同软骨下支架对自体软骨移植修复的影响。结果表明，HA-TCP 支架支撑的移植软骨层具有更好的结构整合和更高的机械强度，优于 PLGA/HA-TCP 支架支撑的移植软骨层。此外，HA-TCP 支架支撑的软骨表现出更高的酸性粘多糖和糖胺聚糖含量的表达，优于 PLGA/HA-TCP 支架支撑的软骨。我们的结果表明，支架的物理化学性质，包括固有机械强度和材料化学，在影响自体软骨移植修复方面起着重要作用。该研究可能为设计和选择合适的软骨下生物材料以支持软骨下骨和软骨缺损的修复提供有用的信息。
