小鼠胚胎与成体肝脏中干细胞变化的探讨

目的 依据干细胞生物学特性,探讨从胚胎到成体肝脏内具干细胞特性细胞的变化状况.方法 分离不同胎龄与日龄小鼠肝脏细胞进行体外培养,观察分离获得的细胞数、培养形成的集落数及生长状态,并对集落进行干细胞表面标记物(c-kit、c-Met、Nestin)、肝细胞表面标记物(AFP、ALB)及胆管上皮细胞表面标记物(CK19)的标记.结果 各组分离的细胞经体外培养均有集落形成,肝干细胞的表面标记提示形成的集落具有肝干细胞特性.其中以第15天胚胎肝脏分离所获的细胞数和培养形成的集落数最多、生长状态最好.15 d后观察的各项指标渐减,细胞生长状态渐差.结论 早期胚胎肝脏中大部分是具有干细胞特性的细胞,随胎龄增加,有干细胞特性的细胞逐渐减少,直至出生第5天仅有少数保持未分化状态的细胞存留在肝脏内.

Evolution of hepatic stem cells fetal to adult of Mouse

Objective To study the evolution of hepatic stem cells from fetal to adult of mouse. Methods Mice were divided into 5 groups according to the gestational (embryo duration, ED13, ED15 and ED19) or born age (day1 and 5).Hepatic stem cells were isolated and cultured in vitro.The amount of the stem cells as well as their growing situation were observed and compared among groups,and markers of stem cells (c-kit,c-Met,Nestin),hepatic cells (AFP,ALB) and biliary epithelial cells (CK19) were used to identify the cultures.Results All isolated cells of each group grew as colonies in vitro.Their expression of specific markers suggested that they were hepatic stem cells.Among groups,the maximum quantity of isolated stem cells and the best situation of growing (maximum growing colonies) were obtained from ED15 group.The growing status of cells and other markers decreased gradually after ED15.Conclusion It is suggested that a majority of cells have characteristics of hepatic stem cells in early age of fetal liver,and cells which have characteristics of hepatic stem cells decrease gradually,only a few cells keep undifferentiating state along with the gestational age until born age (day5).