HBV preS2-S DNA免疫诱导小鼠体液免疫应答

Specific homoral immune response in mice induced by HBV preS2-S gene DNA immunization

目的:构建HBV表面抗原preS2 S 基因表达质粒,并探讨其在小鼠体内的表达及诱导体液免疫应答的能力。方法:采用PCR方法,以PBR322 HBV2.0(adr亚型)质粒DNA为模板获得HBV preS2 S 基因,并将其重组进入pcDNA3.0表达载体中,转染7721细胞系进行稳定表达;以此重组质粒免疫小鼠,ELISA方法检测免疫小鼠抗HBs抗体浓度。结果:构建了HBV preS2 S 基因的表达质粒pcDNAS2 S,该表达质粒可在7721 细胞中稳定高效表达;免疫接种小鼠2 周后抗HBs抗体浓度明显升高,接种后第4周布比卡因处理组小鼠抗HBs抗体的浓度达到峰值161.4 mIU/ml,布比卡因非处理组第5周抗HBs抗体的浓度可达133.7 mIU/ml。结论:所构建的pcDNAS2 S表达质粒能有效表达并诱导小鼠体液免疫应答。

Objective:To construct HBV preS2-S gene expression vector and evaluate its efficacy for inducing humoral immune response in mice. Methods: The PBR322-HBV2.0 (adr subtype) plasmids, which contains 2 copies of HBV genomic DNA, were used as template and HBV S2-S fragment was extended by PCR. The target gene was subcloned into pcDNA3.0 vector and transfected into 7721 cells. The serum anti-HBsAg antibody of DNA-mediated mice was deteced by ELISA after immunization of the plasmid through intramuscular administration. Results: The pcDNAS2-S expression vector was constructed successfully and expressed preS2-S protein effectively in 7721 cell line. The level of anti-HBsAg antibody, which was detected firstly 1 week after the injection of the pcDNAS2-S expression vector, increased to a peak (161.3 mIU/ml ) at 4 weeks in the group treated with bupivacaine and to 133.7 mIU/ml at 5 weeks in the group without bupivacaine treatment. Conclusion: The pcDNAS2-S expression vector can be expressed effectively and it can induce the humoral immune response in mice.