目的：探讨HN基因在NDV抗肿瘤上发挥的作用。方法：以pVAX1为表达载体构建了含NDV HN基因的pVHN核酸疫苗，以脂质体介导方法在体外转染OS732细胞72 h后，用3，5 二羟基甲苯法测定OS732细胞膜唾液酸含量的变化。6周龄BALB/c鼠左后肢皮下接种2×10 6个S180肿瘤细胞，分别于肿瘤接种后的第7天（肿瘤直径为2～3 mm）和第17天瘤内注射100 μg核酸重组体，同时设pVAX1对照组和单纯荷瘤对照组。荷瘤鼠经治疗后框窦采血，分离血清，测定血清唾液酸含量。取脾，采用FACS方法测定淋巴细胞亚群数量的变化。结果：pVHN体外转染OS732细胞后，能显著降低细胞表面唾液酸含量(P<0.05)。pVHN应用于荷瘤鼠显著降低血清中唾液酸含量（P<0.05），引起CD8+T淋巴细胞亚群数量的增加（P<005）。结论：单独HN基因在体外转染能够降低肿瘤细胞表面唾液酸含量，体内表达后引起T淋巴细胞亚群数量改变。

Objective:To investigate the role of HN in NDV antitumor. Method: Nucleic recombinant plasmid pVHN was constructed with pVAX1 and NDV HN gene and transfected into OS732 cells in vitro. 72 h after transfection, OS732 cells were collected and the content of cell surface sialic acid was measured. 6 weeks old BALB/c mice were implanted with S180 sarcoma through the injection of 2×10 6 S180 cells. On 7th day and 17th day after tumor transplantation,100 μg pVHN recombinant plasmid was administered intratumorly in vivo respectively. Control group was treated with pVAX1 as the same method. Serum of BALB/c mice bearing S180 sarcoma was separated and measured the content of sialic acid. T lymphocyte subsets were detected by FACS combined with rat anti mouse CD3+, CD4+, CD8+ antibodies. Results:pVHN was constructed correctly and expressed in OS732 cell. pVHN reduced the surface sialic acid of OS732 cell significantly in vitro. Expression of pVHN in vivo augmented CD8+ T lymphocyte subset and decreased serum sialic acid content. Conclusion: HN gene plays an important role in the reduction of sialic acid and the augmentation of CD8+ T lymphocyte subset

本研究受自然科学基金重大项目（39893290-4-3）和国家“973”项目（G199011902）资助