OBJECTIVE Recent studies suggest xenogeneic extracellular matrices as potential regenerative tools in dental pulp regeneration. This study aimed to fabricate and characterize a novel three-dimensional macroporous pulp-derived scaffold that enables the attachment, penetration, proliferation and differentiation of mesenchymal stem cells. METHOD Bovine pulp was decellularized and characterized with histological and DNA content methods. This scaffold was prepared using finely milled lyophilized decellularized pulp extracellular matrix (ECM) digested with pepsin. Three different concentrations of ECM (1.50, 2.25 and 3.00mg/ml) were freeze-dried and were tested with/without chemical crosslinking. The specimens were subjected to physicochemical characterization, cell viability and quantitative real time polymerase chain reaction assessments with human bone marrow mesenchymal stem cells (hBMMSCs). All scaffolds were subcutaneously implanted in rats for two weeks and histological and immunostaining analyses were performed. RESULTS Histological and DNA analysis confirmed complete decellularization. All samples demonstrated more than 97% porosity and 1.50mg/ml scaffold demonstrated highest water absorption. The highest cell viability and proliferation of hBMMSCs was observed on the 3.00mg/ml crosslinked scaffolds. The gene expression analysis showed a significant increase of dmp-1 and collagen-I on 3.00mg/ml crosslinked scaffolds compared to the other scaffolds. Histological examination of subcutaneous implanted scaffolds revealed low immunological response, and enhanced angiogenesis in cross-linked samples compared to non-crosslinked samples. SIGNIFICANCE The three-dimensional macroporous pulp-derived injectable scaffold developed and characterized in this study displayed potential for regenerative therapy. While the scaffold biodegradability was decreased by crosslinking, the biocompatibility of post-crosslinked scaffold was significantly improved.

中文翻译：

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纸浆ECM衍生的大孔支架，用于刺激牙髓再生过程。

目的最近的研究表明异种细胞外基质是牙髓再生中潜在的再生工具。这项研究旨在制造和表征新颖的三维大孔纸浆衍生的支架，使间充质干细胞的附着，渗透，增殖和分化成为可能。方法采用组织学和DNA含量方法对牛牙髓进行脱细胞和鉴定。使用经胃蛋白酶消化的细磨的冻干脱细胞果肉细胞外基质（ECM）制备此支架。将三种不同浓度的ECM（1.50、2.25和3.00mg / ml）冷冻干燥，并在有/无化学交联的情况下进行测试。对标本进行了理化鉴定，人骨髓间充质干细胞（hBMMSC）的细胞活力和定量实时聚合酶链反应评估。将所有支架皮下植入大鼠中两周，并进行组织学和免疫染色分析。结果组织学和DNA分析证实完全脱细胞。所有样品均显示出超过97％的孔隙率，而1.50mg / ml支架显示出最高的吸水性。在3.00mg / ml的交联支架上观察到hBMMSC的最高细胞活力和增殖。基因表达分析表明与其他支架相比，在3.00mg / ml交联支架上dmp-1和I型胶原蛋白显着增加。皮下植入支架的组织学检查显示免疫反应低，与非交联样品相比，交联样品中的血管生成增强。意义本研究中开发和表征的三维大孔髓衍生注射支架显示了再生疗法的潜力。尽管通过交联降低了支架的生物降解性，但后交联支架的生物相容性却得到了显着改善。