人牙源性间充质细胞构建牙本质-牙髓复合体样结构的实验研究

目的以复合生长因子的陶瓷化骨和Collagraft为载体建立人牙源性间充质细胞的体内立体培养模型，构建牙本质-牙髓复合体样结构。方法将经生长因子诱导的人牙源性间充质细胞接种于复合同种生长因子的陶瓷化骨和Collagraft复合材料上，将细胞-支架复合物移植到裸鼠皮下，建立牙源性间充质细胞的体内立体培养模型。4周和10周后取材，对移植物进行组织学观察和人牙本质涎蛋白（DSP）的免疫组化染色。结果10周的实验组标本中，植入细胞在复合生长因子支架上形成了较典型的牙本质-牙髓复合体样结构，人DSP在新生牙本质样组织中呈阳性表达。对照组及4周标本中未观察到此现象。结论用人牙源性间充质细胞和复合生长因子的陶瓷化骨或Collagraft支架材料在裸鼠体内可成功构建出牙本质-牙髓复合体样结构。

Tissue engineering of dentin-pulp complex-like structures by human dental mesenchymal cells

OBJECTIVE: To establish three-dimensional culture model of human dental mesenchymal cells and bioengineer in vivo with ceramic bovine bone (CBB) and Collagraft as scaffolds. METHODS: Human dental mesenchymal cells induced upon stimulation of bFGF and IGF-1 or TGF-beta(1) were implanted onto CBB and Collagraft containing the same kinds of growth factors respectively. Then cell/scaffold constructs were transplanted into nude mice to establish in vivo culture model of dental mesenchymal cells. Control groups were set up at the same time. After 4 weeks or 10 weeks, the implants were taken out for histological and immunohistochemical analysis. RESULTS: Within 10-week implant tissues, typical dentin-pulp complex-like structures were generated in scaffolds containing growth factors. Human dentin sialoprotein (DSP) was expressed in the newly formed dentin. This phenomenon wasn't observed in control groups and 4-week implants. CONCLUSIONS: Dentin-pulp complex-like structures could be bioengineered successfully with human dental mesenchymal cells and CBB or Collagrafts containing growth factors in nude mice.