Objective: To investigate the effects of natural killer group 2 member D (NKG2D) and its ligands major histocompatibility complex class Ⅰ chain-related molecules A(MICA) on DNT cell killing pancreatic carcinoma. Methods: Antibodies adsorption was used to separate DNT cell from human peripheral blood. Human pancreatic tumor models were established via implanting BXPC-3 cells into nude mice, and then mice were randomly divided mice into 3 groups, blank group, gemcitabine group and DNT group. Mice weights and mice tumor volumes were measured every 5 days. After 40 days mice were euthanized at cervical dislocation method. Tumor weights were measured. Relative tumor volume and tumor inhibition rate were calculated. Western blot and qPCR were used to detect the expressions of NKG2D and MICA in the transplanted tumors of the three groups. Results: The blank group tumor volume and weight of blank group were significantly larger than those of gemcitabine group and DNT group (858.7±35.7 mg, 251.1±19.7 mg, 278.5±17.3 mg, P<0.001), but there were no significantly difference between DNT group and gemcitabine group. The tumor inhibition rate of gemcitabine and DNT cell were 40.4% and 35.5%. Western blot and qPCR showed that MICA mRNA and protein levels in blank group were significantly higher than those in DNT group (P=0.001, P=0.003). NKG2D mRNA and protein levels in blank group were significantly lower than those in DNT cells group (P<0.001, P=0.001). Conclusion: DNT cell can significantly inhibit the growth of pancreatic carcinoma in vivo, and the mechanism may be involved in abnormal expressions of MICA and NKG2D.
目的： 探讨NKG2D受体及其相关配体MICA在DNT细胞过继免疫治疗胰腺癌裸鼠移植瘤模型中的作用。 方法： 采用抗体吸附法培养从健康志愿者外周血中分离的DNT细胞，将人胰腺癌细胞株BXPC－3注入30只BALB/c裸鼠腋窝皮下建立裸鼠胰腺癌移植瘤模型。将裸鼠随机分为空白组、吉西他滨组和DNT组，每组10只。运用抗体吸附法从人外周血中分离出的DNT细胞培养、扩增后通过鼠尾静脉治疗。每5天测量裸鼠重量和肿瘤体积测量。40 d后在使用颈椎脱位法处死裸鼠取出肿瘤组织。称重，计算相对肿瘤体积和肿瘤抑制率。运用Western印迹法和qPCR法检测NKG2D和MICA在3组裸鼠胰腺癌移植瘤中的表达。 结果： 空白组肿瘤重量明显高于吉西他滨组和DNT组[(858.7±35.7)mg，(251.1±19.7)mg和(278.5±17.3)mg，P<0.001]，而吉西他滨组和DNT组间无明显差异。吉西他滨组和DNT组肿瘤抑制率分别为40.4%和35.5%。Western印迹和qPCR检测结果显示空白组裸鼠瘤体中MICA的mRNA和蛋白表达水平要明显高于吉西他滨组和DNT组(P＝0.001, P＝0.003)，然而NKG2D的mRNA和蛋白表达水平要明显低于吉西他滨组和DNT组(P<0.001, P＝0.001)。 结论： DNT细胞对胰腺癌裸鼠种植瘤具有显著的抑瘤作用，发挥作用的机制与NKG2D－MICA通路相关。.
Keywords: DNT cell; MICA; NKG2D; Pancreatic carcinoma.