人肝癌HepG2细胞小鼠荷瘤模型的建立及免疫耐受的探讨

Establishment of a tumor-bear mouse model carrying human HepG2 cells and exploration of immune tolerance

目的建立正常免疫背景小鼠的人肝癌荷瘤模型,探讨人肿瘤细胞与胎鼠异种嵌合产生的免疫耐受。方法用绿色荧光蛋白(GFP)标记人肝癌细胞系Hep G2,将GFP-Hep G2细胞注射入孕16.5d的胎鼠腹腔内,观察新生小鼠腹腔内荷瘤情况及酶联免疫吸附法(ELISA)检测荷瘤小鼠血清人甲胎蛋白(AFP)含量;小鼠成年后进行皮下成瘤实验及流式细胞术检测小鼠脾脏T淋巴细胞亚群变化。结果观察到经胎鼠腹腔注射的人GFPHep G2细胞在新生鼠体内种植并生长于肝脏,分泌人甲胎蛋白;皮下荷瘤实验观察到经胎体注射GFP-Hep G2细胞诱导免疫耐受后,部分小鼠成年后仍可支持皮下Hep G2细胞荷瘤,流式细胞术检测表明,诱导耐受后的小鼠免疫系统仍对人肝癌细胞保留有较弱的攻击。结论通过胎鼠腹腔注射人GFP-Hep G2细胞可以建立人肝癌细胞小鼠荷瘤模型,部分荷瘤后的小鼠具有免疫耐受的能力。

Objective To establish an in vivo human hepatoma model carried by mice with normal immune background and to investigate the effect of immune tolerance. Methods We firstly generated green fluorescent protein（ GFP） expressed HepG2 cells and intrauterine injected these cells into the peritoneal cavities of E16. 5 day mouse fetus.Then we observed the change in newborn mice with bearing cancer and detect the human alpha fetoprotein（ AFP）expression in mouse serum by elisa analysis. We subcutaneously injected the HepG2 cells into the adult mice and detected the lymphocyte subgroup ratio of spleen cells by flow cytometry. Results GFP-HepG2 cells were grown in fetus liver and secreted human AFP. After injection of GFP-HepG2 cells in fetus liver,some adult mice developed subcutaneous tumors.Flow cytometry analysis indicated that immune system of tumor-bear mice remained weak attack to human live cancer cells.Conclusion The tumor-bear model carrying human HepG2 cells may be established by injecting the GFP-Hep G2 cells into the peritoneal cavities of mouse fetus,parts of which acquire the ability of immune tolerance.