Molecular biological analyses of cranio-maxillo-facial bone metabolism and application of the gene therapy

人模式充质干细胞（hMSCs）是一种具有高度增殖能力的细胞，其细胞周期受骨形态发生蛋白-2 （BMP-2）和碱性成纤维细胞生长因子（bFGF）的调控。BrDU、PCNA（增殖细胞核抗原）和PTTG（垂体肿瘤转化基因）等细胞周期的基因表达分别在整个、GO/G1和G2/M期得到很好的体现。超微结构分析表明，BMP-2通过改变细胞核（常染色质向异染色质）和细胞质（光滑内质网向颗粒内质网）的形态来分化hMSCs。在再生医学中，使用hMSCs和适当的支架（如天然明胶），伴随着BMP-2和bfgf_起始，颅骨再生速度加快。碱性磷酸酶（ALP）在含有地塞米松、抗坏血酸和β -甘油磷酸酯的成骨培养基培养中，在上清和细胞中均观察到高表达水平。移植骨髓间充质干细胞后4周，成骨细胞因子和人ALP、骨钙素的免疫组化表达显著，骨量增加。这些结果可以解释hMSCs在成骨谱系的再生医学中是有用的。未来，该方案可能与hMSCs基因治疗联合使用，以治疗严重的骨代谢异常。

The human modesenchymal stem cells,(hMSCs) are highly proliferative and cell-cycle regulated by applications of bone morphogenetic protein-2 (BMP-2) and basic fibroblast growth factor (bFGF). The gene expressions of the cell cycles such as BrDU, PCNA (proliferating cell nuclear antigen) and PTTG (pituitary tumor transforming gene) are well demonstrated at entire, GO/G1 and G2/M phase, respectively. Ultrastrucural analyses revealed that hMSCs are differentiated upon BMP-2 administration by changing the nuclear (of euchromatin to heterochromatin) and cytoplasmic (smooth endoplasmic reticulum to granular endoplasmic reticulum) morphology. In regenerative medicine using hMSCs and the proper scaffold such as a natural gelatin, there are accelerated cranial bone regeneration together with BMP-2 and bFGF_initiations. High expression levels of alkaline phosphatase (ALP) in osteogenic medium culture, which contains dexamethasone, ascorbic acid, and beta-glycerophosphate, observed in both supernatant and cells. In 4 weeks after transplanting hMSCs and osteogenic cytokines demonstrated the significant immunohistochemical expressions of human ALP and osteocalcin as well as increased bone mass. These results may explain that hMSCs are useful in regenerative medicine in osteogenic lineage. In future, this regimen may be used in conjunction with gene therapy on hMSCs for severe abnormal bone metabolism.