胚胎干细胞源性肝干细胞在治疗性肝再生中的应用

Application of ESC-derived hepatic stem cells in therapeutic liver repopulation

目的:应用治疗性肝再生模型进行胚胎干细胞(ESC)源性肝干细胞肝内移植,观察其在肝组织替代、体内的生长分化及成瘤性等情况,为ESC移植在难治性肝病治疗中的临床应用提供实验依据。方法:倒千里光碱+70%肝部分切除建立BALB/c小鼠的治疗性肝再生模型。用荧光示踪剂CFDASE标记移植细胞,将经淤胆血清"病理微环境"筛选体系筛选出的ESC源性肝干细胞经门静脉移植入治疗性肝再生模型小鼠肝内。然后荧光显微镜下观察,检测移植细胞体内分布、整合与肝细胞替代、体内生长分化等情况。2周后行白蛋白荧光免疫组化(双荧光染色)、血清白蛋白水平检测其功能状况。并通过观察其体内成瘤性对筛选出的ESC源性肝干细胞的安全性进行评估。结果:CFDASE标记的ESC源性肝干细胞肝内移植1周,受体小鼠肝实质内可见散在绿色荧光分布。2周后,肝实质内绿色荧光分布区域明显扩大,且可见类似肝索样结构排列。共焦白蛋白荧光免疫组化(双荧光染色)结果表明,受体小鼠肝组织内可见标记细胞表达白蛋白阳性信号(呈黄色荧光),血清白蛋白水平则无明显差异(P>0.05)。6周内未见畸胎瘤形成,而将未分化的ESC移植入小鼠腋区皮下6周后则可见畸胎瘤形成。结论:经淤胆血清"病理微环境"筛选体系筛选出的ESC源性肝干细胞移植入治疗性肝再生模型小鼠肝内后可有效整合入宿主肝板、在肝内能进一步生长分化并部分表达肝细胞功能。其安全性较好,6周内未见畸胎瘤形成。

AIM ： To study the proliferation, differentiation and the capacity of forming teratomas of ESC - derived hepatic stem cells in mouse pre - treated with retrorsine and 70% partial hepatotomy. METHODS： The ESC - derived hepatic stem cells, labelled with CFDA SE, were transplanted into BALB/c mouse liver. The distribution, incorperation and proliferation of transplanted cells were observed under fluorescent microscopy. Hepatic function was assayed by detecting albumin level in serum. The situation of forming teratomas in vivo was also evaluated. RESULTS- 1 week post transplantation, some scattered region was green under fluorescent microscopy. The aera of green region increased apparently in 2 weeks, and cord -like. structure was observed. Immunofluorescent staining of albumin demonstrated some positve cells, but there was no significant difference for albumin level in serum （ P 〉 0. 05 ）. No teratoma was formed in the experimental group, while a large teratoma was observed in control group in 6 weeks post - transplantation. CONCLUSION ： The ESC - derived hepatic stem cells are normally incorporated into mouse liver parenchymal structure, proliferate and differentiate further in vivo and possess some hepatic functions without forming teratomas.