Injectable shear-thinning hydrogels used to deliver endothelial progenitor cells, enhance cell engraftment, and improve ischemic myocardium.
Injectable shear-thinning hydrogels used to deliver endothelial progenitor cells, enhance cell engraftment, and improve ischemic myocardium.
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DOI：
10.1016/j.jtcvs.2015.07.035
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发表时间：
2015-11
期刊：
影响因子：
--
通讯作者：
Atluri P
中科院分区：
文献类型：
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作者：
Gaffey AC;Chen MH;Venkataraman CM;Trubelja A;Rodell CB;Dinh PV;Hung G;MacArthur JW;Soopan RV;Burdick JA;Atluri P
由于缺血心肌的细胞保留率低（<1%）和对缺血心肌的靶向性差，基于细胞的缺血性心脏病治疗的临床转化受到限制。为了解决这些问题，我们开发了一种可注射剪切薄化透明质酸水凝胶（STG）和内皮祖细胞构建物（STG- epc）。STG的组装是由于金刚金和β-环糊精修饰的透明质酸的相互作用。它是剪薄的，允许通过注射器输送，并在缺血心肌内注射后自愈。这种针对缺血心肌边界区的定向治疗使直接细胞递送能够解决心肌梗死后的不良重构。我们假设该系统将在临床可翻译治疗的背景下增强血管生成以改善心肌稳定。从成年雄性Wistar大鼠中收集EPCs (DiLDL+ VEGFR2+ CD34+)，培养，然后悬浮在STG中，使用活死染色法定量EPCs的体外活力。在大鼠急性心肌梗死（左冠状动脉前降支结扎术）后缺血心肌交界区注射STG-EPC构建物。荧光显微镜观察eGFP+ EPCs从构建体向缺血心肌的迁移。观察对照组（PBS注射）、心肌内单独注射EPCs （EPC）、单独注射STG （STG）和凝胶-EPC构建组（STG-EPC）的血管发生、心肌重构和血流动力学功能。采用超声心动图和多普勒血流分析定量血流动力学和心室几何形状。EPCs在STG内表现出活力。注射后1周，与单独注射EPCs相比，凝胶给药心肌内EPCs的植入明显增加（17.2±0.8个细胞/HPF vs. 3.5±1.3个细胞/HPF， p = 0.0002）。与对照组（p < 0.0001）、EPC组（p < 0.0001）和STG组（p < 0.0001）相比，STG-EPC组的血管生成（15.3±5.8支/HPF）有统计学意义的增加。与对照组相比，STG-EPC治疗后心室功能、疤痕分数和几何形状也有统计学上的显著改善。一种新型的可注射剪切薄化透明质酸水凝胶植入内皮祖细胞后，可增强缺血心肌的细胞保留和血管生成。这种疗法限制了不良的心肌重塑，同时保持了收缩性。
The clinical translation of cell based therapies for ischemic heart disease has been limited due to low cell retention (<1%) within and poor targeting to ischemic myocardium. To address these issues, we developed an injectable shear-thinning hyaluronic acid hydrogel (STG) and endothelial progenitor cell construct (STG-EPC). The STG assembles due to interactions of adamantine and β-cyclodextrin modified hyaluronic acid. It is shear-thinning to permit delivery via a syringe, and self-heals upon injection within the ischemic myocardium. This directed therapy to the ischemic myocardial borderzone enables direct cell delivery to address adverse remodeling after myocardial infarction. We hypothesize that this system will enhance vasculogenesis to improve myocardial stabilization in the context of a clinically translatable therapy. EPCs (DiLDL+ VEGFR2+ CD34+) were harvested from adult male Wistar Rats, cultured, and then suspended in the STG. In vitro viability was quantified using a live-dead stain of EPCs. STG-EPC constructs were injected at the borderzone of ischemic rat myocardium after acute myocardial infarction (left anterior descending coronary artery ligation). The migration of the eGFP+ EPCs from the construct to ischemic myocardium was analyzed using fluorescent microscopy. Vasculogenesis, myocardial remodeling, and hemodynamic function were analyzed in 4 groups: control (PBS injection), intramyocardial injection of EPCs alone (EPC), injection of the STG alone (STG), and treatment with the gel-EPC construct (STG-EPC). Hemodynamics and ventricular geometry were quantified using echocardiography and Doppler flow analysis. EPCs demonstrated viability within the STG. A marked increase in EPC engraftment was observed one-week post-injection within the treated myocardium with gel delivery when compared to EPC injection alone (17.2 ± 0.8 cells/HPF vs. 3.5 cells ± 1.3 cells/HPF, p = 0.0002). A statistically significant increase in vasculogenesis was noted with the STG-EPC construct (15.3 ± 5.8 vessels/HPF) when compared to control (p < 0.0001), EPC (p < 0.0001), and STG (p < 0.0001) groups. Statistically significant improvements in ventricular function, scar fraction, and geometry were also noted after STG-EPC treatment compared to the control. A novel injectable shear-thinning hyaluronic acid hydrogel seeded with EPCs enhanced cell retention and vasculogenesis after delivery to ischemic myocardium. This therapy limited adverse myocardial remodeling while preserving contractility.