NK 细胞上清液提高CTL 细胞对肝癌细胞杀伤力的研究

目的：研究用白细胞介素2（IL‐2）联合IL‐12、IL‐18以及三者共同活化NK细胞所提取的上清液与肝癌细胞共培养是否能提高AFP特异性的细胞毒性T细胞（CTL）对小鼠肝癌细胞的杀伤性。方法提取NK 细胞，分别用IL‐26000 IU／mL、IL‐26000 IU／mL＋ IL‐1210 ng／mL、IL‐26000 IU／mL＋IL‐l8100 ng／mL、IL‐26000 IU／mL＋IL‐1210 ng／mL＋IL‐18100 ng／mL活化NK细胞，3 d后提取上清液，ELISA检测上清液IFNγ表达量，然后将上清液与Hepa1‐6细胞培养过夜，流式细胞仪检测肿瘤细胞表面I类组织相容性抗原（M HC I）表达，以其为靶细胞检测AFP特异性的CTL细胞对 Hepa1‐6细胞杀伤率。结果NK＋IL‐2＋IL‐12、NK＋IL‐2＋IL‐18、NK＋IL‐2＋IL‐12＋IL‐18上清液的IFNγ含量高于NK＋IL‐2上清液的IFNγ含量（P＜0．05），并且上述三组能有效提高小鼠 Hepa1‐6细胞表面M HC I的表达（P＜0．05），从而显著提高了AFP特异性的CTL细胞对靶细胞的杀伤活性，然而阻断IFNγ分泌，AFP特异性的CTL细胞对靶细胞的杀伤活性降低。结论 NK 细胞上清液能够增强AFP特异性的CTL对肝癌细胞的杀伤作用。

Supernatants of activated natural killer cells enhance the capability of CTL cells for killing hepatoma cells

Objective To investigate whether supernatants of natural killer (NK)cells activated with IL‐12 ,IL‐18 ,and both with IL‐2 ,can endows AFP specific CTL cells on hepatoma cells function .Methods NK cells were cultured and activated with IL‐12 ,IL‐18 ,and both with IL‐2 ,3 days later extract supernatants of NK cells ,and together culture with hepa1‐6 tumor cells overnight .Then M HC class I expression of hepa1‐6 tumor cells were assayed with flow cytometry ,and as targets for AFP specific CTL cells for cy‐totoxic assay .Results The IFNγ concentrations of NK cells in the supernatants activated with IL‐12 ,IL‐18 ,and both with IL‐2 , were significantly more than NK cells activated with IL‐2(P< 0 .05) ,and which could effectively increase the expression of M HC class I on hepa1‐6 tumor cells to further enhance the capability of CTL cells for killing target cells (P< 0 .05) .However ,blocking the secretion of IFNγdoes the opposite .Conclusion Supernatants from NK cells will induce increased M HC class I expression on target cells and will enhance the fuctionality of killing hepatoma cells on AFP specific CTL cells .