CIK细胞对裸鼠人肝癌移植瘤生长的抑制作用

Inhibitory effect of CIK cells on the growth of human hepatoma xenografts in nude mice

目的探讨细胞因子诱导的杀伤细胞(CIK细胞)对裸鼠人肝癌移植瘤生长的抑制作用,为肝癌的生物治疗提供实验依据。方法提取健康人外周血单个核细胞,加入不同的细胞因子(抗CD3单克隆抗体、重组人白细胞介素2、重组人γ干扰素)促进CIK细胞成熟,采用流式细胞术检测CIK细胞表型,合格标准为CD3^(+)CD56^(+)CIK细胞达20%以上。用SMMC-7721人肝癌细胞建立裸鼠皮下移植瘤模型,随后将30只模型鼠随机分为CIK细胞组(A组,15只)、空白对照组(B组,15只),A组给予尾静脉注入3×10^(7)个检测合格的CIK细胞,每周1次,共4次,B组不予处理。在治疗前及治疗后每4天测量两组肿瘤体积;采用苏木精-伊红染色检测两组肿瘤病理组织学变化;采用免疫组织化学法检测两组肿瘤组织Ki-67蛋白表达情况;采用脱氧核苷酸末端转移酶介导的dUTP缺口末端标记(TUNEL)法检测两组肿瘤细胞凋亡情况。结果治疗前,A、B组肿瘤体积比较,差异无统计学意义(P>0.05);治疗至第32天时,A组肿瘤体积明显小于B组,差异有统计学意义(P<0.05)。治疗至第32天时,CIK细胞抑瘤率为43.06%。A组肿瘤组织Ki-67蛋白表达的吸光度值为0.68±0.11,低于B组的0.80±0.11,差异有统计学意义(P<0.05)。A组凋亡细胞的吸光度值为0.52±0.05,高于B组的0.40±0.05,差异有统计学意义(P<0.05)。结论CIK细胞免疫治疗在体内可抑制裸鼠人肝癌移植瘤生长,其机制可能与活化的CIK细胞抑制肿瘤细胞增殖,促进其凋亡有关,CIK细胞免疫治疗有望成为肝癌的治疗手段之一。

Objective To investigate the inhibitory effect of cytokine-induced killer cells(CIK cells)on the growth of human hepatoma xenografts in nude mice,and to provide experimental evidence for the biological treatment of hepatic carcinoma.Methods Extracted healthy human peripheral blood mononuclear cells,added different cytokines(anti-CD3 monoclonal antibody,recombinant human interleukin 2,recombinant humanγinterferon)to promote the maturation of CIK cells.CIK cells phenotype was detected by flow cytometry,and more than 20%CD3^(+)CD56^(+)CIK cells were qualified.The model of subcutaneous transplantation of SMMC-7721 human hepatoma cell was established in nude mice.Then 30 model mice were randomly divided into CIK cells group(group A,15 mice)and blank control group(group B,15 mice).Group A was given tail vein injection of 3×10^(7)qualified CIK cells,once a week,for a total of 4 times,and group B was not treated.Tumor volumes were measured in both groups before treatment and every 4 d after treatment.Hematoxylin-eosin staining was used to detect the histopathological changes of the two groups of tumors.The expression of Ki-67 protein in two groups of tumor tissues was detected by immunohistochemistry.TUNEL method was used to detect the apoptosis of tumor cells in the two groups.Results Before treatment,there was no significant difference in tumor volume between groups A and B(P>0.05).On the 32nd day of treatment,the tumor volume in group A was significantly smaller than that in group B,and the difference was statistically significant(P<0.05).On the 32nd day of treatment,the tumor inhibition rate of CIK cells was 43.06%.The absorbance value of Ki-67 protein expression in tumor tissue in group A was 0.68±0.11,which was lower than 0.80±0.11 in group B,and the difference was statistically significant(P<0.05).The absorbance value of apoptotic cells in group A was 0.52±0.05,which was significantly higher than 0.40±0.05 in group B,and the difference was statistically significant(P<0.05).Conclusion CIK cells immunotherapy can inhibit the growth of human hepatoma xenografts in nude mice in vivo,and the mechanism may be related to the inhibition of tumor cells proliferation and promotion of apoptosis by activated CIK cells,CIK cells immunotherapy is expected to become one of the treatment methods for hepatic carcinoma.