小鼠牙乳头间充质细胞自发牙向分化及相关基因表达分析  

Spontaneous Odontogenic Differentiation and Critical Gene Expression of Mouse Dental Papilla Mesenchymal Cell in vitro

作　　者：朱锋[1] 聂蓉蓉[2] 吴凌[1] 刘磊[1] 汤炜[1] 田卫东[1] 

机构地区：[1]四川大学华西口腔医院口腔疾病研究国家重点实验室 [2]南京大学医学院附属口腔医院修复科

出　　处：《四川大学学报（医学版）》2008年第2期286-289,297,共5页Journal of Sichuan University(Medical Sciences)

基　　金：国家自然科学基金(批准号30471904);中国博士后科学基金(20060391019);教育部重点研究项目(106134)资助

摘　　要：目的观察小鼠牙乳头间充质细胞在血清培养基中的自发牙向分化,并对其特异性牙向和骨向分化的相关转录因子的基因表达进行分析。方法获取孕16.5 d(E16.5 d)胎鼠的原代牙乳头间充质细胞,分别在含血清培养基和添加白血病抑制因子(LIF)的血清培养基中传代培养,观察细胞是否出现成牙本质细胞表型分化,并检测牙向分化表型和维持未分化表型的细胞的特异性转录因子的mRNA表达情况。结果单纯血清培养基培养的牙乳头间充质细胞可在第4代后自发分化为成牙本质细胞表型;而添加106U/L LIF的含血清培养基,可使小鼠牙乳头间充质细胞的未分化表型稳定至第9代。无论细胞是否出现牙向分化,表现成牙间充质细胞特性的Msx1/Msx2、Pax9、Lhx6/Lhx7均有表达;而成牙本质细胞表型分化后尚能检测到DSPP、Sox9、Cbfα1、Osx等启动向矿化组织细胞终末分化的特异性基因表达。结论牙乳头间充质细胞的自发牙向分化模型可作为诱导其他成体间充质干细胞牙向分化时的阳性对照,其基因表达模式可为研究其他成体干细胞牙向分化后在基因水平上的变化提供佐证。Objective To observe the spontaneous odontogenic differentiation of mouse dental papilla mesenchymal cells in blood serum medium. And to detect the critical gene expression of correlated transcription factors what are specific to odontogenic and osteogenic differentiation. Methods The primary dental papilla mesenchymal cells what had been obtained from E16.5 d murine embryo were serially subcultivated in the simple serum medium and the serum medium supplemented with LIF（leukocyte inhibitory factor） respectively. It was observed whether the dental papilla mesenchymal cells differentiated into odontoblast phenotype or kept the undifferentiation phenotype. The mRNA expression of specific transcription factors were detected in cells with or without odontogenic differentiation. Results The fourth generation and behind of mouse dental papilla mesenchymal cells what were cultured in simple serum medium could spontaneously differentiate to odontoblast, while the undifferentiation phenotype of dental papilla mesenchymal cells could be lasting to ninth generation when they cultured in medium supplemented with 10^6 U/L LIF. Whether the dental papilla cells differentiate to odontogenic phenotype or not, the members of HOX gene family such as Msx1/Msx2, Pax9 and Lhx6/Lhx7 got completely expression. These transcription factors were specific to odontogenic mesenchymal cells. Also the specific gene of mineralized tissue cells such as DSPP, Sox9, Cbfα1 and Osx initiated to express after the odontoblast differentiation. Conclusion Not only this spontaneous odontogenic differentiation model of mouse dental papilla mesenehymal cells can be the positive control, but also the mode of gene expression can provide an evidence for studying how gene changes when adult stem cells are induced to odontogenie differentiation.

关 键 词：小鼠牙乳头间充质细胞 白血病抑制因子 牙向分化 基因表达 

分 类 号：R78[医药卫生—口腔医学]