Establishment of in vitro culture system for evaluating dentin-pulp complex regeneration with special reference to the differentiation capacity of BrdU label-retaining dental pulp cells
Establishment of in vitro culture system for evaluating dentin-pulp complex regeneration with special reference to the differentiation capacity of BrdU label-retaining dental pulp cells
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DOI：
10.1007/s00418-014-1200-7
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发表时间：
2014-09-01
影响因子：
2.3
通讯作者：
Ohshima, Hayato
中科院分区：
文献类型：
--
作者：
Ida-Yonemochi, Hiroko;Nakatomi, Mitsushiro;Ohshima, Hayato
我们提出了新的假设，即牙髓干细胞与祖细胞合作，在外源刺激后的牙髓愈合过程中发挥着至关重要的作用。本研究旨在建立评估牙本质-牙髓复合体再生的体外培养系统，特别是慢循环长期标记保留细胞（LRC）的分化能力。对怀孕的 ICR 小鼠进行 3 次腹腔注射 BrdU，以绘制出生动物成熟组织中的 LRC。拔出3周龄小鼠双侧第一磨牙，分成两块，用镘刀法培养0、1、3、5和7天。我们成功建立了评估牙本质-牙髓复合体再生的体外培养系统，其中大多数成牙本质细胞偶尔会退化并失去巢蛋白免疫反应性，因为体外培养开始时细胞体与牙本质基质中的细胞过程分离。在整个实验期间，大量致密的LRC主要位于与血管相关的牙髓中心。术后第1-3天，包括成牙本质细胞层在内的牙髓组织周边出现退行性特征。到第7天，巢蛋白阳性的成牙本质细胞样细胞沿着牙髓-牙本质边界排列，并且致密的LRC在成牙本质细胞样细胞中定型。这些结果表明，牙髓中心与血管相关的致密LRCs被认为是牙髓干/祖细胞，具有形成新分化的成牙本质细胞样细胞的再生能力。
We have proposed the new hypothesis that dental pulp stem cells play crucial roles in the pulpal healing process following exogenous stimuli in cooperation with progenitors. This study aimed to establish an in vitro culture system for evaluating dentin-pulp complex regeneration with special reference to the differentiation capacity of slow-cycling long-term label-retaining cells (LRCs). Three intraperitoneal injections of BrdU were given to pregnant ICR mice to map LRCs in the mature tissues of born animals. The upper bilateral first molars of 3-week-old mice were extracted and divided into two pieces and cultured for 0, 1, 3, 5 and 7 days using the Trowel's method. We succeeded in establishing an in vitro culture system for evaluating dentin-pulp complex regeneration, where most odontoblasts were occasionally degenerated and lost nestin immunoreactivity because of the separation of cell bodies from cellular processes in the dentin matrix by the beginning of in vitro culture. Numerous dense LRCs mainly resided in the center of the dental pulp associating with blood vessels throughout the experimental periods. On postoperative days 1-3, the periphery of the pulp tissue including the odontoblast layer showed degenerative features. By Day 7, nestin-positive odontoblast-like cells were arranged along the pulp-dentin border and dense LRCs were committed in the odontoblast-like cells. These results suggest that dense LRCs in the center of the dental pulp associating with blood vessels were supposed to be dental pulp stem/progenitor cells possessing regenerative capacity for forming newly differentiated odontoblast-like cells.