人参皂苷Rg1联合重组大肠杆菌不耐热肠毒素rLTB作为滴鼻免疫佐剂在小鼠体内的作用研究

Effect of ginsenoside Rg1 in combination with recombinant Escherichia coli heat-labile enterotoxin rLTB as intranasal adjuvant in mice

为探究人参皂苷Rg1和重组大肠杆菌不耐热肠毒素rLTB联合滴鼻免疫小鼠的佐剂效果,本研究以卵清白蛋白(OVA)为模式抗原,分别将生理盐水、OVA、OVA+Rg1、OVA+rLTB、OVA+Rg1-rLTB滴鼻免疫小鼠,共免疫3次。利用血液细胞分析仪分析小鼠外周血中白细胞的变化;荧光定量PCR检测小鼠脾细胞中细胞因子mRNA转录水平;ELISA法检测小鼠血清、胆汁、肺泡支气管和阴道黏液中IgA和IgG抗体水平。结果显示,与OVA单独免疫组相比,Rg1-rLTB能够明显促进小鼠中性粒细胞和中间细胞数量的增加(p<0.05),显著上调Th1、Th2和Th17型细胞因子的转录水平(p<0.05),明显提高血清和局部黏膜中的OVA特异性IgA和IgG抗体水平(p<0.05),并且Rg1-rLTB的复合佐剂效果比单独Rg1或rLTB更具优势。因此,Rg-rLTB可以作为一种新型的滴鼻免疫佐剂,值得进一步的深入研究。

The aim of this study was to investigate the effect of ginsenoside Rg1 in combination with recombinant B subunit of Escherichia coli heat-labile enterotoxin rLTB as intranasal adjuvant in mice.In this study,ovalbumin(OVA)was used as an antigen model.Mice were intranasally immunized with saline,OVA,OVA mixed with Rg1,OVA with rLTB,or OVA with Rg1-rLTB for 3 times.The changes of white blood cells in peripheral blood were analyzed by blood cell analyzer;mRNA transcription levels of cytokines in splenocytes were detected using real-time PCR;the titers of IgA and IgG antibody in serum,bile,bronchoalveolar lavage fluid and vaginal fluid were measured by ELISA.The results showed that Rg1-rLTB significantly increased the numbers of neutrophils and intermediate cells(p<0.05),remarkably stimulatedthe transcription levels of Th1,Th2 and Th17 type cytokines(p<0.05),and enhanced OVA-specific IgA and IgG antibody responses in serum and local mucosa(p<0.05)of mice when compared with the OVA alone group.Furthermore,the combined adjuvant of Rg1 and rLTB has more advantageous effect than that of Rg1 or rLTB.Therefore,as a novel intranasal adjuvant,Rg1-rLTB deserves further study.