Elder Steven, Clune John, Walker Jaylyn, Gloth Paul
Agricultural & Biological Engineering, Mississippi State University, Mississippi State, MS 39762, USA.
J Funct Biomater. 2017 Sep 23;8(4):43. doi: 10.3390/jfb8040043.
As a non-crosslinked osteochondral xenograft would be mechanically inferior to native cartilage and vulnerable to premature degradation, we seek a safe and effective method of xenograft stabilization. The purpose of this study was to evaluate the capacity for epigallocatechin gallate (EGCG) to stabilize a decellularized porcine osteochondral xenograft through collagen crosslinking. Our objectives were to assess the effects of EGCG on the degree of crosslinking, mechanical properties, collagenase resistance, cytotoxicity, and in vitro biocompatibility. EGCG is a green tea polyphenol that acts as a collagen crosslinker. Porcine osteochondral plugs were decellularized and then crosslinked by soaking in EGCG. The degree of crosslinking, cartilage compressive stiffness, cartilage-bone interface strength, coefficient of friction, and residual mass after collagenase exposure all increased with an increasing EGCG concentration. With the exception of the coefficient of friction, EGCG treatment could restore mechanical properties to levels equal to, or exceeding those, of native cartilage. EGCG treatment profoundly increased the enzymatic resistance, and 1% EGCG provided protection equivalent to 1% glutaraldehyde. EGCG up to 0.5 mM was essentially not cytotoxic to chondrocytes embedded in alginate, and autologous chondrocytes attached to decellularized, EGCG-fixed cartilage were all viable five days after seeding. Results demonstrate that EGCG has many beneficial effects on a decellularized osteochondral xenograft, and may be suitable for use in stabilizing such a graft prior to implantation for the repair of a defect.
由于非交联的骨软骨异种移植物在力学性能上不如天然软骨，且易过早降解，因此我们寻求一种安全有效的异种移植物稳定方法。本研究的目的是评估表没食子儿茶素没食子酸酯（EGCG）通过胶原交联来稳定脱细胞猪骨软骨异种移植物的能力。我们的目标是评估EGCG对交联程度、力学性能、抗胶原酶能力、细胞毒性和体外生物相容性的影响。EGCG是一种绿茶多酚，可作为胶原交联剂。将猪骨软骨栓脱细胞，然后通过浸泡在EGCG中进行交联。随着EGCG浓度的增加，交联程度、软骨压缩硬度、软骨-骨界面强度、摩擦系数以及胶原酶处理后的残余质量均增加。除摩擦系数外，EGCG处理可将力学性能恢复到等于或超过天然软骨的水平。EGCG处理显著提高了酶抗性，1%的EGCG提供了与1%戊二醛相当的保护作用。高达0.5 mM的EGCG对包埋在藻酸盐中的软骨细胞基本无细胞毒性，接种五天后，附着在脱细胞、EGCG固定软骨上的自体软骨细胞均存活。结果表明，EGCG对脱细胞骨软骨异种移植物有许多有益作用，可能适用于在植入修复缺损前稳定此类移植物。
