Peng Gordon, McNary Sean M, Athanasiou Kyriacos A, Reddi A Hari
Lawrence Ellison Center for Tissue Regeneration and Repair, Department of Orthopaedic Surgery, School of Medicine, University of California, Davis, Sacramento, CA, USA.
Lawrence Ellison Center for Tissue Regeneration and Repair, Department of Orthopaedic Surgery, School of Medicine, University of California, Davis, Sacramento, CA, USA; Department of Biomedical Engineering, University of California, Davis, CA, USA.
Cartilage. 2016 Jul;7(3):256-64. doi: 10.1177/1947603515612190. Epub 2015 Oct 26.
Previous work has shown that increasing the production of boundary lubricant, superficial zone protein (SZP), did not reduce the friction coefficient of self-assembled articular cartilage constructs and was possibly due to poor retention of the lubricant. The aim of this investigation was to reduce the friction coefficient of self-assembled articular cartilage constructs through enhancing SZP retention by the exogenous addition of extracellular matrix (ECM) extracted from the superficial zone of native articular cartilage.
Superficial zone cartilage was shaved from juvenile bovine femoral condyles using a dermatome, minced finely with razor blades, extracted with 4 M guanidine-hydrochloride, buffer exchanged with culture medium, and added directly to the culture medium of self-assembled articular cartilage constructs at low (10 µg/mL) and high (100 µg/mL) concentrations for 4 weeks. Biochemical and biomechanical properties were determined at the conclusion of 4 weeks culture.
ECM treatment increased compressive and tensile stiffness of self-assembled articular cartilage constructs and decreased the friction coefficient. Glycosaminoglycan content decreased and collagen content increased significantly in self-assembled constructs by the ECM treatment.
Friction coefficients of self-assembled articular cartilage constructs were reduced by adding extracted superficial zone ECM into the culture medium of self-assembled articular cartilage constructs.
先前的研究表明，增加边界润滑剂即表面区蛋白（SZP）的产生，并不能降低自组装关节软骨构建体的摩擦系数，这可能是由于润滑剂保留不佳所致。本研究的目的是通过外源添加从天然关节软骨表面区提取的细胞外基质（ECM）来增强SZP的保留，从而降低自组装关节软骨构建体的摩擦系数。
使用皮刀从幼年牛股骨髁上刮下表面区软骨，用剃须刀片精细切碎，用4 M盐酸胍提取，与培养基进行缓冲液交换，然后以低浓度（10 µg/mL）和高浓度（100 µg/mL）直接添加到自组装关节软骨构建体的培养基中，持续4周。在4周培养结束时测定生化和生物力学特性。
ECM处理增加了自组装关节软骨构建体的压缩和拉伸刚度，并降低了摩擦系数。通过ECM处理，自组装构建体中的糖胺聚糖含量降低，胶原蛋白含量显著增加。
通过向自组装关节软骨构建体的培养基中添加提取的表面区ECM，可降低自组装关节软骨构建体的摩擦系数。
