温度敏感的水凝胶与富血小板血浆复合体对大鼠前交叉韧带部分损伤愈合的作用

摘要

目的:探讨温度敏感的水凝胶与富血小板血浆(platelet-rich plasma,PRP)对大鼠前交叉韧带(anterior cruciate ligament,ACL)部分损伤的愈合是否有促进作用.方法:按照既往文献报道的方法制备PRP,将其与温度敏感的水凝胶——单甲氧基聚乙二醇-聚乳酸乙醇酸嵌段共聚物(mPEG-PLGA)在特定条件下混合,制备成复合体.共采用110只12周龄雄性Sprague-Dawley大鼠右侧膝关节,其中10只作为完整对照组(n=10,ACL无损伤),其余100只随机分为2组:损伤对照组(n=60,ACL部分损伤后用生理盐水处理损伤部位)、实验组(n=40,ACL部分损伤后将mPEG-PLGA-PRP复合体注射于损伤部位).共观察三个时间点:手术后即刻、术后2周和术后6周.观察并比较组间与组内的组织学与生物力学变化.结果:组织学结果表明,实验组术后6周组织学观察可见ACL损伤已出现部分愈合,炎性细胞减少,出现新生纤维组织,但走行与正常ACL组织仍有差异,可见新生血管形成.韧带成熟度评分,实验组显著高于损伤对照组(20.6±4.9 vs 4.7±1.0,P＜0.01).生物力学实验结果表明,术后6周拉断强度实验组显著高于对照组(52.7±11.2 vs 30.3±8.8,P＜0.05).结论:在大鼠模型下采用mPEG-PLGA-PRP复合体治疗ACL部分损伤,术后6周在组织学与生物力学方面与对照组相比均有显著改善,但是尚未恢复到损伤前的水平.%Objective To explore the effect of the temperature-sensitive hydrogel and platelet-rich plasma(PRP)complex on the healing of anterior cruciate ligament (ACL)partial tear in a rat model.Method PRP was processed according to an established method and then mixed with poly(ethylene glycol)monomethyl ether and poly(lactic-co-glycolic acid)(mPEG-PLGA).A total of 110 right knees of Sprague-Dawley male rats (12-week old)were included and randomly divided into a healthy control group (n=10),a lesion control group(n=60)and a study group(n=40).The saline and mPEG-PLGA-PRP complex was applied at the lesion site respectively.Samples were harvested 0,2 weeks and 6 weeks post-operatively and the histological and biomechanical changes were observed and compared among the 3 groups.Results Histologically,at 6 weeks after surgery,the torn ACL of the study group had been partially healed,with decreased number of inflammatory cells and new fibrous tissues and micro-vessels appearing.The ligament maturity index revealed a significantly higher score in the study group than the lesion control group(20.6 ± 4.9 vs.4.7 ± 1.0,P＜0.01).Biomechanically,at 6 weeks after surgery,the tensile strength of the study group was significantly higher than the contro] groups(52.7 ± 11.2 vs.30.3 ± 8.8,P＜0.05).Conclusion At six weeks after surgery,the mPEG-PLGA-PRP complex can enhance the healing of ACL partial tear,ahhough the ligament was not recovered to the norma] state.