肝癌mRNA致敏的DC对SCID荷瘤鼠的抑瘤作用

目的通过重建人肝癌PBL-SCID嵌合模型来观察mRNA致敏的树突状细胞疫苗（mRNA DC）在体内的抑瘤效应并探讨机制。方法采用人外周血淋巴细胞腹腔注射法建立Hu-PBL-SCID鼠模型,尾静脉分别注射mRNA DC疫苗、抗CD4^＋、CD8^＋＋mRNA DC、未致敏的树突状细胞（DC）。每周1次,共两次,然后接种2×10^6HepG-2cells,观察鼠成瘤率、成瘤潜伏期、肿瘤体积以及测定特异性CTL活性。结果ELISA法可检测到鼠血清中人IgG水平,Hu-PBL-SCID嵌合模型重建成功,各组小鼠间成瘤率无明显差异,但mRNA DC组成瘤潜伏期延长,肿瘤生长缓慢,2周后肿瘤体积明显小于抗CD4^＋、CD8^＋＋mRNA DC组、DC组和PBS组,差异有统计学意义（P〈0.05）,实验组脾淋巴细胞对HepG-2细胞有特异性杀伤效应,而对胃癌SGC-7901细胞则无杀伤活性。结论mRNA致敏的树突状细胞疫苗体内能诱导产生明显的抑瘤作用。

The suppression of tumor growth induced by dendritic cell vaccine sensitized with HCC RNA in severe combined immune deficiency mice

Objective To reconstruct human hepatocellular carcinoma chimeric model of peripheral blood lymphocytes in severe combined immune deficiency in mice and investigate the inbibiting tumor action and mechanism of mRNA-dendritic cells（mRNA DC） vaccine. Methods HuPBL-SCID chimeric model was established by intraperitoneal injection of human peripheral blood lymphocytes. The mRNA DC vaccine,anti CD4^＋,CD8^＋ antibody＋mRNA DC,naive DC were injected respectively through taited vein, and then they were injected subcutaneously with 2×10^6 HepG-2 cells. Tumorigenic rate, latent period, and tumor volume were observed, and specific CTL activity were measured. Results The serum concentration of human IgG in Hu-PBL- SCID model was confirmed by Elisa. It suggested that the Hu-PBL-SCID model was established successfully. Tumorigenic rate was no significant difference among the four groups. However, tumors grew slowly in mRNA DC vaccine group, and its latent period was prolonged. Tumor volumes were significantly smaller than those in anti CD4^＋,CD8^＋ antibody ＋mRNA DC group, PBS group and naive DC group two week later. The splenic cells in mRNA DC vaccine group would specifically kill HepG-2 cells but not for SGC-7901 cells of gastric cancer. Conclusion mRNA DC vaccine can induce anti-tumor immune response in vivo.