富血小板血浆复合再生支架修复兔骨软骨缺损

Platelet rich plasma combined scaffold for the repair of osteochondral defect in rabbit knee

[目的]观察富血小板血浆(PRP)复合支架修复新西兰兔膝关节骨软骨缺损的效果。[方法]抽取成年新西兰兔静脉血,两次离心后获取PRP。采用10%Ca Cl2激活其中的血小板,ELISA法检测激活前后TGF-β的浓度。成年新西兰兔在股骨内髁软骨面上制备骨软骨缺损模型。按缺损置入处理,将动物分为三组,分别是空白对照组、单纯支架组和PRP-支架组。术后6、12周取材,进行大体观察和国际软骨修复协会(ICRS)大体形态评分,此外,采用HE染色和番红O-固绿染色进行组织观察评估。[结果]PRP激活后TGF-β的浓度显著高于未激活时(P<0.05)。术后6周,单纯支架组与PRP-支架组的ICRS评分显著高于空白对照组(P<0.05);术后12周,单纯支架组与PRP-支架组的ICRS评分仍显著高于空白对照组(P<0.05),且PRP-支架组的评分显著高于单纯支架组(P<0.05)。HE染色与番红O-固绿染色表明,单纯支架组和PRP-支架组的修复明显优于空白对照组,且PRP-支架组的修复较单纯支架组更优。[结论]单纯支架能够促进兔膝关节骨软骨缺损的修复,但修复效果有限。激活后的PRP能够明显提高支架的作用,PRP-支架是此动物实验中最佳的骨软骨修复方式。

[Objective] To assess the outcome of platelet rich plasma（PRP） combined scaffold for the repair of osteochondral defect in rabbit kne. [Methods] PRP from the venous blood of adult New Zealand rabbit was prepared after centrifugation twice, and then 10% solution of Ca Cl2 was added to PRP in proportion of 1：9 for platelet activation. The concentration of TGF-βwas tested by ELISA before and after the activation. After anaesthetization, a full-thickness cylindrical osteochondral defect was created on the medial condylar articular surface of the distal femur. In term of the osteochondral defect treated, the animals were divided into three groups, including blank control, the scaffold only and the PRP combined scaffold（PRP-scaffold） group.At 6 and 12 weeks after surgery the animals were sacrificed, gross evaluation with the International Cartilage Repair Society（ICRS） macromorphological scoring was conducted and compared among the three groups. In addition, histological assessment by Hematoxylin-eosin staining and safranin O-fast green staining were done. [Results] After activation, the concentration of TGF-β increased significantly（P〈0.05）. The ICRS scores of both the scaffold only group and the PRP-scaffold group were significantly higher than that of the blank control at 6 and 12 weeks after surgery（P〈0.05）, additionally, the score of the PRP-scaffold group was significantly higher than that of the scaffold only group at 12 weeks（P〈0.05）. Furthermore, the histological assessments with Hematoxylin-eosin staining and safranin O-fast green staining revealed significantly improved osteochondral regeneration in the PRP-scaffold group over the scaffold only group and the blank control group. [Conclusion] The scaffold does improve the repairing of the osteochondral defect, but the effect is limited. After activated PRP is added, the role of scaffold is significantly enhanced. PRP-scaffold may be the best choice for osteochondral regeneration in this animal experiment.