混合信号诱导的大鼠骨髓间充质干细胞与支架材料复合成牙的体内研究

目的:研究经碱性成纤维细胞生长因子(bFGF)与骨形态发生蛋白2 (BMP-2)混合信号诱导的大鼠骨髓间充质干细胞(BMSCs)在体内环境中与不同支架材料复合后的成牙潜能。方法:将取自SD大鼠的BMSCs与牙胚细胞在bFGF和BMP-2混合信号诱导的微环境中共培养后分别接种于明胶海绵和3D打印的PVA/DCCP复合支架材料上,然后回植入同种异体大鼠肾被膜下。在回植后的第1、3、7、14、28天采集回植体样本,用实时定量PCR (RT-PCR) 检测各组样本成牙相关基因成釉蛋白 (AMBN)、牙本质基质蛋白1 (DMP1)、Ⅰ型胶原蛋白 (Collagen-Ⅰ)、以及同源异型盒基因1 (DLX1) mRNA水平。结果:各基因在不同时间点的表达量与完整牙胚(E组)均存在统计学差异(P＜0.05);上述4个成牙相关基因的表达水平在不同支架材料组之间具有显著性差异(P＜0.001);不同成牙诱导信号对各个基因的表达水平也有一定影响。结论:在体内模拟环境下,经bFGF与BMP-2混合信号诱导的大鼠BMSCs与3D打印支架材料复合后能提高成牙基因的表达水平,促进牙体组织的形成。优选支架材料并构建合适的组织工程牙模型对实现非牙胚源性细胞向牙源性细胞的转化同样具有重要意义

Tooth-forming Potential of Rat Bone Marrow Mesenchymal Stem Cells in the Milieus of Diverse Growth-Factor Induction and Scaffold in Vivo.

Objective: To investigate the tooth-forming potential of bone marrow mesenchymal stem cells (BMSCs) in the milieus of diverse growth-factor signaling inductions and scaffolds in vivo. Methods: BMSCs were inducted via either a single signaling mixed multi-signaling. The BMSCs were further co-cultured in GS or polyvinyl alcohol-double crystal ceramic powder (PVA-DCCP) scaffold constructed by a 3D printer. The re-implanted tissues were harvested and the RT-PCR of ameloblastin (AMBN), DMP1, Collagen-1, and DLX1 mRNA were performed at 1, 3, 7, 14 and 28 days after implantation to assess teeth-forming potential histologically and genetically. Results: With prolongation of culturing, the mRNA level increased in Collagen-1, whereas decreased in AMBN, DMP1 and DLX1 in the five groups; and the mRNA levels of four genes were significantly lower in group A-D than that in group E (P＜0.05). Furthermore, the mRNA levels were significantly different among tissue samples with diverse scaffolds (P<0.001). Conclusion: BMSCs induced by mixed multi-signaling could proliferate more quickly and differentiate more profoundly, compared to the single signaling induced ones. Moreover, these BMSCs expressed more corresponding odontogenic genes which promoted the formation of tooth tissue when combined with diverse scaffolds.