Functional human hepatocytes xenografted into the liver of mice can be used as a model system to study pharmacokinetics,infection of hepatitis viruses,and the efficacy of hepatitis vaccines.Significant levels of liver xeno-repopulation have been reported in Fah-/-Rag2-/-Il2rg-/-mice.However,the high mortality and low breeding rate of this model may hinder its application.A new model,termed Fah-/-Nod/Scid mice,which combines the advantages of liver repopulation in Fah-/-mice with the ease of xenotransplantation in Nod/Scid mice was obtained by gradual cross-breeding.Fah-/-Nod/Scid mice were easily maintained in breeding colonies and in adult animal care facilities.FK506 treatment combined with gradual withdrawal of NTBC before cell transplantation ensured that Fah-/-Nod/Scid mice were susceptible to liver xeno-repopulation by human hepatocytes;the proportion of engrafted human hepatocytes reached 33.6%.The function of the expanded human hepatocytes within the chimeric liver was confirmed by weight curve analysis,the expression of characteristic proteins,and the biochemical analysis of liver function.These results show that Fah-/-Nod/Scid mice are an ideal humanized liver mouse model with many useful applications.
背景与目的:采用体外获得性表达外源发状分裂相关增强子-1(hairy and enhancer of split1,Hes1)基因的方法,探讨Hes1在肝干细胞分化以及胆管上皮细胞发育中的作用。材料与方法:通过PCR方法从小鼠基因组中克隆Hes1基因片段,构建表达载体pEGFP-C1-Hes1和pcDNA3.1-Hes1,将2种表达载体分别转染肝原始细胞系(LEPCs),应用RT_PCR和Real-timePCR技术检测胆管细胞分子标志物CK19、GGT,胆管上皮细胞相关转录因子HNF6、HNF1β,肝细胞分子标志物GS、BGP和肝卵圆细胞的分子标志物Thy-1的表达,并在荧光显微镜下观察EGFP标记的LEPCs细胞系荧光强度的变化。结果:成功构建表达载体pEGFP-C1-Hes1和pcDNA3.1-Hes1。RT-PCR和Real_timePCR检测均表明胆管细胞分子标志CK19、GGT表达量上调;胆管上皮细胞相关转录因子HNF6、HNF1β表达上调;肝细胞分子标志GS、BGP表达量下调;卵圆细胞的分子标志Thy-1表达量下调;LEPCs细胞系绿色荧光增强。结论:初步证明小鼠肝原始细胞经Hes1的表达诱导后可向胆管上皮细胞方向分化,推测Hes1为胆管上皮细胞分化的转录调控因子。
