探讨玉竹多糖(Polygonatum odoratun polysaccharides, POP)对流感病毒裂解疫苗黏膜免疫的佐剂效果。以BALB/c小鼠为模型, 将H7N9流感病毒裂解疫苗单独或者添加不同剂量的POP(400、600、800、1 000和1 200 μg)做佐剂一次性滴鼻免疫小鼠, 免疫三周后小鼠以致死剂量同源病毒攻击。实验结果表明, 当在疫苗中加入1 000 μg POP时, 与疫苗单独免疫相比, 单次滴鼻免疫就明显增强了小鼠抵抗致死量病毒感染的能力, 体重丢失减少, 肺部残余病毒滴度下降, 存活率提高; 血清中疫苗特异性IgG抗体和HI抗体以及鼻洗液中SIgA抗体都提高了; IgG亚类抗体检测显示, POP的加入显著增加了IgG1的抗体滴度, 但抑制了IgG2a的产生, 说明诱导的免疫应答偏向于Th2型。实验表明POP在一定剂量时能增强疫苗诱导的免疫应答, 显示出黏膜佐剂效应。

Mucosal adjuvant effect of Polygonatum odoratun polysaccharides (POP) was explored. BALB/c mice were immunized intranasally with influenza virus H7N9 split vaccine alone or together with POP at different amounts. Three weeks after the immunization, mice were challenged with lethal dose of homologous virus. The results showed that, when mice were administrated with the vaccine plus 1 000 μg POP, they could be well protected against the infection, with significantly reduced weight loss, low lung virus titers and increased survival rate, as compared with the vaccine-alone group; their specific IgG and HI antibody titers in sera and SIgA titers in nasal washes accordingly increased significantly. Moreover, the IgG subclass antibody detection revealed induction of Th2-biased immune response by addition of POP. The experiments initially indicated that POP has mucosal adjuvant effect on the split vaccine.