Synergy of tendon stem cells and platelet-rich plasma in tendon healing

Injured rat Achilles tendons were treated with botulism toxin to create a mechanically unloaded condition (unloaded) or left untreated (loaded), and then treated with phosphate-buffered saline (PBS), platelet-rich plasma (PRP), tendon stem cells (TSCs), or a combination (TSCs?+?PRP). mRNA and protein expression of collagen I, collagen III, tenascin C, and Smad 8 were determined by real time PCR and immunostaining, respectively. Loaded tendons treated with PBS, PRP, or TSCs for 3 or 14 days had higher collagen I mRNA expression than unloaded tendons. Loaded tendons treated with PBS for 3 or 14 days or with PRP for 3 days had higher collagen I protein levels than unloaded tendons. Loaded tendons treated for 3 days with PBS, for 14 days with PRP or TSCs or TSCs?+?PRP for 3 or 14 days had higher collagen III protein levels than unloaded tendons. Collagen I mRNA levels were higher in TSCs?+?PRP-treated loaded tendons compared to PBS-treated loaded tendons on day 3 of treatment. Based on changes in the expression of tendon-healing genes, our data suggest that the combination of TSCs and PRP has synergistic effects on tendon healing under both loaded and unloaded conditions, and loaded conditions improve tendon healing. (c) 2011 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:991997, 2012

用肉毒杆菌毒素处理受伤大鼠的跟腱以创造机械性卸载条件（卸载组），或不进行处理（加载组），然后分别用磷酸盐缓冲盐水（PBS）、富血小板血浆（PRP）、肌腱干细胞（TSCs）或联合使用（TSCs + PRP）进行治疗。通过实时聚合酶链反应和免疫染色分别测定Ⅰ型胶原蛋白、Ⅲ型胶原蛋白、腱生蛋白C和Smad8的信使核糖核酸（mRNA）及蛋白质表达。加载组的肌腱用PBS、PRP或TSCs处理3天或14天后，其Ⅰ型胶原蛋白mRNA表达高于卸载组肌腱。加载组肌腱用PBS处理3天或14天，或用PRP处理3天，其Ⅰ型胶原蛋白水平高于卸载组肌腱。加载组肌腱用PBS处理3天、用PRP或TSCs处理14天，或用TSCs + PRP处理3天或14天，其Ⅲ型胶原蛋白水平高于卸载组肌腱。在治疗第3天，与用PBS处理的加载组肌腱相比，用TSCs + PRP处理的加载组肌腱中Ⅰ型胶原蛋白mRNA水平更高。基于肌腱愈合相关基因表达的变化，我们的数据表明，在加载和卸载条件下，TSCs和PRP的联合使用对肌腱愈合具有协同作用，并且加载条件可促进肌腱愈合。（c）2011骨科研究学会。由威利期刊公司出版。《矫形外科学研究杂志》2012年30卷991 - 997页