目的　以EB病毒潜伏膜蛋白 2 (latentmembraneprotein 2 ,LMP2 )为靶基因 ,构建EBV LMP2的侯选DNA疫苗 ;并初步探讨其在小鼠体内诱导特异性细胞毒方面的作用 ,为研制鼻咽癌 (na sopharyngealcarcinoma ,NPC)等EB病毒相关肿瘤的治疗性疫苗提供有益资料。方法　将EB病毒LMP2全cDNA片段克隆至含CMV早期启动子的真核表达载体pcDNAⅢ上 ,构建CMV启动子EB病毒LMP2DNA疫苗。在体外将重组质粒转染COS细胞 ,以RT PCR和间接免疫荧光法检测重组质粒在转染的COS细胞中的转录和表达。采用 5 0 μg、10 0 μg、2 0 0 μg 3种质粒剂量进行初步的小鼠免疫试验。结果　重组质粒可在真核细胞中有效地转录和表达LMP2。免疫接种小鼠后可诱发机体产生针对LMP2蛋白的特异性体液免疫和细胞免疫。 5 0 μg、10 0 μg、2 0 0 μg 3种免疫剂量产生的抗体水平差异不大。在免疫接种 6周后 ,重组质粒免疫的小鼠产生针对LMP2的特异性CTL均明显高于空载体免疫小鼠。 3种剂量的CTL结果显示 :在 10 0 μg、2 0 0 μg免疫组 ,小鼠诱导产生的CTL水平要略高于 5 0 μg免疫组。结论　EB病毒重组质粒LMP2免疫小鼠可以诱发小鼠产生特异的体液和细胞免疫应答。这些结果为研制鼻咽癌DNA疫苗提供有益的资料 OBJECTIVE: To construct EBV LMP2 candidate DNA vaccine targeting latent membrane protein 2 (LMP2) as a target gene and to explore its role in inducing specific cytotoxicity in mice. na sopharyngealcarcinoma, NPC) and other Epstein-Barr virus-related therapies provide useful information. Methods The complete cDNA fragment of Epstein-Barr virus LMP2 was cloned into the eukaryotic expression vector pcDNAⅢ containing CMV early promoter to construct CMV promoter EBV LMP2 DNA vaccine. The recombinant plasmids were transfected into COS cells in vitro, and the transcription and expression of recombinant plasmids in transfected COS cells were detected by RT PCR and indirect immunofluorescence. Initial mouse immunization tests were performed using three plasmid doses of 50 μg, 100 μg, and 200 μg. Results Recombinant plasmids could efficiently transcribe and express LMP2 in eukaryotic cells. Immunization of mice can induce the body to produce specific humoral and cellular immunity against LMP2 protein. The antibody levels produced by the three immunized doses of 50 μg, 100 μg and 200 μg did not differ significantly. After 6 weeks of immunization, the recombinant plasmid-immunized mice produced significantly higher specific CTLs against LMP2 than the empty vector-immunized mice. Three doses of CTL results show that: in the 100 μg, 200 μg immunization group, mice induced CTL levels slightly higher than the 50 μg immunization group. Conclusion The EBV recombinant plasmid LMP2 immunized mice can induce specific humoral and cellular immune responses in mice. These results provide useful information for the development of nasopharyngeal DNA vaccine