School and Hospital of Stomatology, Wuhan University, Wuhan 430079, Hubei Province, People's Republic of China.
J Biomed Mater Res A. 2010 Apr;93(1):247-57. doi: 10.1002/jbm.a.32535.
The aim of current study is to investigate the in vitro and in vivo behavior of dental pulp stem cells (DPSCs) seeded on electrospun poly(epsilon-caprolactone) (PCL)/gelatin scaffolds with or without the addition of nano-hydroxyapatite (nHA). For the in vitro evaluation, DNA content, alkaline phosphatase (ALP) activity and osteocalcin (OC) measurement showed that the scaffolds supported DPSC adhesion, proliferation, and odontoblastic differentiation. Moreover, the presence of nHA upregulated ALP activity and promoted OC expression. Real-time PCR data confirmed these results. SEM micrographs qualitatively confirmed the proliferation and mineralization characteristics of DPSCs on both scaffolds. Subsequently, both scaffolds seeded with DPSCs were subcutaneously implanted into immunocompromised nude mice. Scaffolds with nHA but without cells were implanted as control. Histological evaluation revealed that all implants were surrounded by a thin fibrous tissue capsule without any adverse effects. The cell/scaffold composites showed obvious in vivo hard tissue formation, but there was no sign of tissue ingrowth. Further, the combination of nHA in scaffolds did upregulate the expression of specific odontogenic genes. In conclusion, the incorporation of nHA in nanofibers indeed enhanced DPSCs differentiation towards an odontoblast-like phenotype in vitro and in vivo.
本研究旨在探究种植于静电纺丝聚己内酯（PCL）/明胶支架上的牙髓干细胞（DPSCs）的体外和体内行为，这些支架添加或不添加纳米羟基磷灰石（nHA）。体外评估结果显示，DNA 含量、碱性磷酸酶（ALP）活性和骨钙素（OC）测量表明支架支持 DPSC 黏附、增殖和成牙本质分化。此外，nHA 的存在上调了 ALP 活性并促进了 OC 的表达。实时 PCR 数据证实了这些结果。SEM 微观照片定性证实了 DPSCs 在两种支架上的增殖和矿化特征。随后，将种植有 DPSCs 的两种支架分别皮下植入免疫缺陷裸鼠体内。未种植细胞但含有 nHA 的支架作为对照进行植入。组织学评估显示所有植入物均被一层薄的纤维组织囊包围，没有任何不良反应。细胞/支架复合物显示出明显的体内硬组织形成，但没有组织向内生长的迹象。此外，支架中 nHA 的组合确实增强了 DPSCs 向成牙本质细胞样表型的体外和体内分化。综上所述，纳米纤维中添加 nHA 确实增强了 DPSCs 的体外和体内向成牙本质细胞样表型的分化。
