免疫检查点阻断剂PD-1抗体在小鼠肝细胞癌治疗中的应用

Application of immune checkpoint blocker PD-1 antibody in the treatment of murine hepatocellular carcinoma

目的探讨PD-1抗体在小鼠原位肝癌中的治疗作用。方法通过肝脏原位注射Hepa1-6肝癌细胞株构建小鼠原位肝癌模型,随机分为治疗组(n=14)和模型组(n=14),每组8只取标本,6只观察生存状态。治疗组小鼠腹腔注射PD-1抗体200μg/只,每3 d一次,共注射3次;模型组给予相同体积的生理盐水;给药后每天观察小鼠生存状态。末次给药后第2天,流式细胞术检测肿瘤组织CD3^(+)T、CD4^(+)T、CD8^(+)T、B淋巴细胞和NK细胞比例,及外周血Th1类细胞因子(IL-2、IFN-γ、TNF-α)浓度。结果治疗组小鼠肿瘤直径明显小于模型组(t=3.74,P=0.002)。治疗组小鼠肿瘤组织CD3^(+)T细胞、CD4^(+)T细胞、CD8^(+)T细胞、B细胞和NK细胞比例均明显高于模型组(P<0.001)。治疗组小鼠外周血IL-2水平明显高于模型组(P<0.001),IFN-γ、TNF-α浓度在两组间差异无统计学意义(P>0.05)。治疗组小鼠中位生存时间显著长于模型组(P<0.05)。结论PD-1抗体治疗可以明显增强原位肝癌模型小鼠肿瘤微环境抗肿瘤免疫反应并显著延长小鼠生存期。

Objective To investigate the therapeutic effect of PD-1 antibody in orthotopic hepatocellular carcinoma mice.Methods Mouse orthotopic hepatocellular carcinoma models were established by the orthotopic injection of Hepa1-6 cells,and the tumor-bearing mice were randomly assigned into treatment group(n=14)and model group(n=14),of which,8 for sampling and 6 for observation of survival in each group.Mice in treatment group were intraperitoneally injected with PD-1 antibody 200μg per mouse every three days for three times,and mice in model group were given equal volume of normal saline.The survival time in the two groups was observed.At day 2 after the last treatment,flow cytometry was performed to detect the proportions of tumor infiltrating CD3^(+)T,CD4^(+)T,CD8^(+)T,B,NK cells and the concentrations of Th1 subtype cytokines(IL-2,IFN-γ,TNF-α)in peripheral blood.Results The tumor diameter in treatment group was significantly smaller than that in model group(t=3.74,P=0.002).The proportions of tumor infiltrating CD3^(+)T cell,CD4^(+)T cell,CD8^(+)T cell,B cell and NK cell were significantly higher in treatment group than those in model group(P<0.001).The concentration of IL-2 in treatment group was significantly higher than that in model group(P<0.001),but there was no significant difference in the concentrations of IFN-γand TNF-αbetween the two groups(P>0.05).Median survival time of mice in treatment group was significantly longer than that in model group(P<0.05).Conclusion PD1 antibody treatment can significantly enhance the tumor microenvironment anti-tumor immune response in orthotopic hepatocellular carcinoma model mice,and extend the survival time of mice.