NDV-HN经非依赖IFN途径上调NK细胞TRAIL表达增强抗瘤作用的新机制研究

我们前期的研究工作证实了NDV-HN可通过诱导IFN-r 分泌上调NK细胞TRAIL表达来增强抗瘤作用，然而IFN受体缺陷小鼠的NK细胞经NDV-HN刺激后TRAIL仍能上调表达，此结果提示可能存在NDV-HN经"非依赖IFN途径"上调NK细胞TRAIL表达的新机制，国内外对此尚无报道。所以本项目拟以"非依赖IFN途径"为研究切入点，用酵母双杂交等技术方法开展如下研究：首先明确NK细胞在"非依赖IFN途径"下识别并结合的NDV-HN的氨基酸位点，接着研究参与NK细胞"非依赖IFN途径"上调TRAIL的胞内信号调控分子，最后探讨"NDV-HN-TRAIL"信号通路中关键分子经刺激或阻断处理后效应NK细胞膜上TRAIL等功能性表型及对肝癌细胞杀伤的变化。项目的完成可望进一步阐明NDV-HN活化NK细胞的抗肿瘤免疫机制，也为基于"NDV-HN-NK细胞"输注的肿瘤生物治疗提供新的理论依据。

It is showed that Newcastle disease virus(NDV) can directly and indirectly kill tumor cells in vitro and in vivo, but its mechanisms are not completely clear. Natural killer (NK) cell is one of important killing cells, which can induce apoptosis of target cells through TNF-related apoptosis-inducing ligand-death receptor(TRAIL-DR) pathway. Our privious study shows that NDV can upregulate the TRAIL expression of NK cells through induction of IFN-γ,but TRAIL expression also can be detected on NDV-stimulated NK cell from IFN R-/- mice (fuctional inactivation of the IFN receptor gene, cells from IFNR-/- mice were insensitive to the antiviral activity of IFN).This result reminds us that it is likely that NDV can upregulate the TRAIL expression of NK cells through other pathways without IFN dependance. So we will use molecular biology and other techniques to perform the following work: ①Verify the primary binding site of NKp46 to virual HN through IFN-independance pathway. ②Demonstrate that Syk tyrosine kinase and NF-κB factor have taken part in the regulation of TRAIL in HN-stimulated NK cells through IFN-independance pathway. ③Investigate the effect on effectors and tumoricidal activity of NK cells on hepatoma cell lines by inducing or blocking of molecular involved in IFN-independence pathway. This project will further elucidate the mechanism that NDV kills tumor cells and will provide the new foundamentional theory for the aplication of anti-tumoral therapy based on NDV-HN- stimulated NK cell transfusion.