■脂肪来源的干细胞(ADSC)片已被证明可促进腱-骨愈合。然而,ADSC表的常规实验室制备方法耗时且风险大,这排除了它们多样化的临床应用。
■探索现成的冷冻保存的ADSC片(c-ADSC片)用于肩袖肌腱至骨愈合的实用性。
■对照实验室研究。
■将ADSC片冷冻保存并解冻以活/死双重染色,TdT介导的dUTP缺口标记(TUNEL)染色,扫描电镜观察,和生物力学测试。克隆形成,增殖能力,测定c-ADSC片内ADSCs的多谱系分化以探索冷冻保存对干细胞性质的影响。将67只家兔随机分为4组:正常组(无冈上肌腱撕裂;n=7),对照组(单独修复;n=20),新ADSC(f-ADSC)片材组(修复;n=20),和c-ADSC片材组(修复;n=20)。兔双侧冈上肌腱撕裂,建立慢性肩袖撕裂模型。Grossobservation,显微计算机断层扫描分析,组织学或免疫组织化学测试,修复后6周和12周进行生物力学测试。
■细胞活力没有明显受损,形态学,与f-ADSC板相比,c-ADSC板的机械性能。ADSC片的干细胞特性也通过冷冻保存来保存。修复后6周和12周,f-ADSC和c-ADSC片组显示出较好的骨再生,更高的组织学评分,较大的纤维软骨区域,更成熟的胶原蛋白,与对照组相比,生物力学结果更好。f-ADSC和c-ADSC片组在骨再生方面无明显差异,组织学评分,纤维软骨形成,和生物力学测试。
■c-ADSC表,一个现成的支架,具有很高的临床转化应用潜力,能有效促进肩袖肌腱-骨愈合。
■程序冷冻保存ADSC片是一种有效的现成支架,可用于肩袖肌腱至骨愈合。
Adipose-derived stem cell (ADSC) sheets have been shown to promote tendon-to-bone healing. However, conventional laboratory preparation methods for ADSC sheets are time-consuming and risky, which precludes their diverse clinical applications.
To explore the utility of off-the-shelf cryopreserved ADSC sheets (c-ADSC sheets) for rotator cuff tendon-to-bone healing.
Controlled laboratory study.
The ADSC sheets were cryopreserved and thawed for live/dead double staining, TdT-mediated dUTP Nick-End Labeling (TUNEL) staining, scanning electron microscopy observation, and biomechanical testing. Clone formation, proliferative capacity, and multilineage differentiation of ADSCs within the c-ADSC sheets were assayed to explore the effect of cryopreservation on stem cell properties. A total of 67 rabbits were randomly divided into 4 groups: normal group (without supraspinatus tendon tears; n = 7), control group (repair alone; n = 20), fresh ADSC (f-ADSC) sheet group (repair; n = 20), and c-ADSC sheet group (repair; n = 20). Rabbit bilateral supraspinatus tendon tears were induced to establish a chronic rotator cuff tear model. Gross observation, micro-computed tomography analysis, histological or immunohistochemical tests, and biomechanical tests were conducted at 6 and 12 weeks after repair.
No significant impairment was seen in the cell viability, morphology, and mechanical properties of c-ADSC sheets when compared with f-ADSC sheets. The stem cell properties of ADSC sheets also were preserved by cryopreservation. At 6 and 12 weeks after the repair, the f-ADSC and c-ADSC sheet groups showed superior bone regeneration, higher histological scores, larger fibrocartilage areas, more mature collagen, and better biomechanical results compared with the control group. No obvious difference was seen between the f-ADSC and c-ADSC sheet groups in terms of bone regeneration, histological score, fibrocartilage formation, and biomechanical tests.
c-ADSC sheets, an off-the-shelf scaffold with a high potential for clinical translational application, can effectively promote rotator cuff tendon-to-bone healing.
Programmed cryopreservation of ADSC sheets is an efficient off-the-shelf scaffold for rotator cuff tendon-to-bone healing.