Department of Biomedical Science, University of Foggia Medical School, Foggia, Italy.
J Biol Regul Homeost Agents. 2010 Apr-Jun;24(2):167-75.
Stem cells are a promising tool for bone tissue regeneration. Dental pulp stem cells (DPSCs) can be easily obtained even in human young adults. In this study we investigated the capability of DPSCs, to express the osteoblastic phenotype when cultured with osteogenic medium. DPSCs isolated from the dental pulp of impacted third molar teeth were cultured with appropriate medium to induce osteoblast differentiation. Using Western-Blot, RT-PCR and microarray analysis, we studied the expression of osteoblastic parameter, and by Von Kossa staining we evaluated the production of mineralized matrix nodules. The results were compared with controls represented by undifferentiated DPSCs. DPSCs, differentiated into osteoblast-like cells, express large amount of alkaline phosphatase (ALP), collagen I (Coll I), osteopontin (OPN) and osteocalcin (OCN), all these parameters characterizing the osteoblastic phenotype. Differentiated DPSCs express Runx2 and JunB, a member of the AP-1 complex; both the transcription factors are associated with osteoblast differentiation and skeletal morphogenesis. Moreover, DPSCs express insulin growth factor-binding protein 5 (IGFBP-5), one of the regulating proteins of IGFs function. Finally, DPSCs can form mineralized matrix nodules that are a feature exclusive to osteoblasts. DPSCs could represent a potential source of osteoblasts to be used for bone regeneration.
干细胞是骨组织再生的有前途的工具。牙髓干细胞（DPSCs）即使在人类年轻成年人中也可以很容易地获得。在这项研究中，我们研究了 DPSCs 在与成骨培养基一起培养时表达成骨细胞表型的能力。从阻生第三磨牙牙髓中分离的 DPSCs 用适当的培养基培养以诱导成骨细胞分化。通过 Western-Blot、RT-PCR 和微阵列分析，我们研究了成骨细胞参数的表达，并通过 Von Kossa 染色评估矿化基质结节的产生。将结果与未分化的 DPSCs 代表的对照进行比较。分化为成骨样细胞的 DPSCs 表达大量碱性磷酸酶（ALP）、胶原 I（Coll I）、骨桥蛋白（OPN）和骨钙素（OCN），所有这些参数均表征成骨细胞表型。分化的 DPSCs 表达 Runx2 和 JunB，AP-1 复合物的成员；这两种转录因子都与成骨细胞分化和骨骼形态发生有关。此外，DPSCs 表达胰岛素样生长因子结合蛋白 5（IGFBP-5），IGF 功能的调节蛋白之一。最后，DPSCs 可以形成矿化基质结节，这是成骨细胞特有的特征。DPSCs 可以成为用于骨再生的成骨细胞的潜在来源。
