神经中间丝蛋白Nestin在胎肝中的表达

Expression of nestin, an intermediate filament protein, in human fetal hepatic stem cells

目的采用免疫组织化学方法标记不同发育时期人胚胎肝干细胞中巢蛋白(Nestin)的表达,探讨肝干细胞新的表面标志蛋白。方法取材不同发育时期胎儿肝脏,固定并制成石蜡切片,ABC法标记神经前体细胞的特异性表面标记Nestin在胎肝干细胞中的表达。结果汇管区周边界板处卵圆样干细胞表达Nestin阳性,Nestin阳性细胞呈单层紧密排列成管,呈鞘样包绕着早期汇管区,部分包绕着初级汇管区,随着次级汇管区的成熟,Nestin阳性卵圆样干细胞逐渐局限于赫令管周围;此外胚胎发育不同时期可见Nestin阳性单个核样细胞散布在肝实质内。结论肝脏内有Nestin表达阳性的干细胞存在,其功能、来源需要进一步深入研究。

Objective To explore a new oval cell marker by examining the expression of nestin in human fetal hepatic stem cells in various stages during human fetal development. Methods Human fetal tissue samples of various developmental stages were obtained and fixed for preparation of paraffin sections. The expression of nestin, generally recognized as a specific marker for neural precursor cells, in fetal hepatic stem cells was detected using immunocytochemical staining (ABC method). Results Nestin-positive oval cells, characterized to be hepatic stem cells, were found in the limiting plate, which arranged tightly in monolayer to form ductules that encapsulated the early-stage portal area in a sheath-like fashion, and also partially encapsulated the primary portal area. With the development of the secondary portal areas, the nestin-positive oval cells gradually centered around the Hering canal. In addition, some nestin-positive mononuclear cells were found scattering in the hepatic cords and sinusoids, especially in the mesenchymal tissue of the portal areas. Conclusion Nestin-positive oval cells exist in human fetal liver and their origin and function await further investigation.