A new culture system for studying in vitro human dental pulp repair

在这项研究中，我们研究了厚切片的行为，从人类牙齿钻孔后立即提取和培养3天至1个月，结果表明，损坏的牙髓下的腔是能够发展，在体外，一些典型的方面与组织愈合，证明细胞增殖，新生血管，和功能立方细胞的存在接近受伤的区域。培养30天后，可以看到细长的梭形细胞沿着相关牙本质壁的边缘排列，而健康区域下方的成牙本质细胞功能良好。组织修复使我们相信，这种培养模型将是一个有用的系统，用于测试调控牙髓修复的因素。神经递质肽P物质（SP）广泛分布于中枢和外周神经系统，也已发现在非神经组织中。据报道，它在许多生理功能中发挥免疫调节作用。SP刺激大鼠牙本质牙髓复合体中的T细胞增殖，刺激人单核细胞产生炎性细胞因子，包括白细胞介素（IL）-1、IL-6、IL-10、IL-12、肿瘤坏死因子-α。我们的研究结果表明，VR 1增强LPS诱导的人类牙本质牙髓复合体培养系统中炎症分子基因的表达。此外，我们的数据表明，LPS诱导VR 1在这些文化中的表达。以上结果提示，在人牙本质牙髓复合体培养中，LPS上调了细胞对VR 1的反应，VR 1在牙本质牙髓复合体的炎症和敏感性中起重要作用。

In this study, we investigated the behavior of thick slices from human teeth drilled immediately after extraction and cultured from 3 days to 1 month, Results shows that the damaged pulp beneath the cavity is able to develop, in vitro, some typical aspects correlated to tissue healing, evidenced by cell proliferation, neovascularization, and the presence of functional cuboidal cells close to the injured area. After 30 days of culture, elongated spindle-shaped cells can be seen aligned along the edges of the relevant dentin walls, whereas sound functional odontoblasts are well-preserved beneath healthy areas. Tissue recovery leads us to believe that such a culture model will be a useful system for testing factors regulating pulp repair.The neurotransmitter peptide substance P (SP) is widely distributed in the central and peripheral nervous systems and also has been found in nonneural tissues. This one has been reported to play an immunoregulatory role in many physiological functions. SP stimulates T-cell proliferation in rat dentin-pulp complex and stimulates human monocytes to produce inflammatory cytokines, including interleukin (IL) -1, IL-6, IL-10, IL-12,tumor necrosis factor-α. Our results demonstrate that VR1 enhances LPS-induced expression of genes for inflammatory molecules in human dentin-pulp complex culture systems. In addition, our data show that LPS induces expression of VR1 in these cultures. This results suggest that LPS up-regulates the cellular response to VR1 in human dentin-pulp complex cultures.In summary, our findings show that VR1 plays important role in dentin-pulp complex inflammation and sensitivity.