丙烯醇致肝损伤微环境定向诱导骨髓干细胞向肝细胞分化

Differentiation of bone marrow derived Thy-1^+ β_2M^- cells into liver cells in AA induced liver injury microenvironment

目的探讨丙烯醇导致的肝损伤环境对大鼠骨髓来源的Thy-1+β2M-细胞(BDTCs)向肝脏细胞诱导分化的影响。方法用免疫磁分选方法分离雄性F344大鼠BDTCs,以PKH26标记后经门静脉输注入受者雌性F344大鼠体内。30只受者随机分为3组,A组:丙烯醇损伤+BDTCs移植组;B组:正常+BDTCs移植组;C组:丙烯醇损伤+等渗盐水对照组。术后不同时间行血清生物化学检测,经荧光标记细胞定位、原位杂交检测Y染色体sry基因表达和免疫组织化学等方法检测移植的BDTCs在受体肝脏内分布、增殖和分化情况。结果荧光显微镜和sry基因原位杂交均发现,供体BDTCs在丙烯醇所致的坏死汇管区附近呈片状或索条状分布;免疫组织化学结果显示,汇管区附近的部分新生细胞序贯性表达OV-6、甲胎蛋白、细胞角蛋白19和白蛋白,而B组肝内几乎未见阳性细胞出现;A组和C组血清生物化学指标恢复正常所需时间分别为(9.8±3.1)d和(13.7±4.2)d。结论丙烯醇致肝汇管区坏死的微环境有利于BDTCs整合至肝细胞板中并向成熟的肝细胞分化,BDTCs在向肝细胞分化的同时还可能促进内源性的肝细胞再生和修复。

Objective To investigate the differentiation of bone marrow derived Thy-1+β2M-cells (BDTCs) into liver cells in allyl alcohol (AA) induced liver injury micro-environment. Methods BDTCs of male F344 rats were isolated by two-step magnetic separation system (MACS) technique, and infused intraportally into female recipients after labeling with PKH26. Thirty recipients were divided randomly into 3 groups: (1) AA-injured liver + BDTCs infusion, (2) normal liver + BDTCs infusion and (3) AA-injured liver + NS infusion (control). Blood biochemical examination, fluorescence labeled cellular localization, Y-chromosome sry gene in-situ hybridization and immunohistochemistry were carried out to evaluate BDTCs distribution, differentiation and proliferation in recipients' livers after different intervals. Results Fluoromicroscopy and in situ hybridization suggested that BDTCs of donors were interspersed in pieces and cords among the necro-periportals induced by AA; immunohistochemistry indicated that those implanted cells expressed OV-6, AFP, CK19 and albumin successively, while positive cells were hardly seen in the normal liver + BDTCs infusion group. Compared with the controls, the blood biochemical restitution was more rapid in group (1), (9.8 d±3.1 d vs 13.7 d±4.2 d,P<0.05). Conclusion The injury micro-environment induced by AA facilitates BDTCs integration with hepatic cell plates and differentiation into mature liver cells. BDTCs differentiation into liver cells might accelerate endogenous liver cell regeneration and reparation.