双歧杆菌对Ⅰ+Ⅲ型二价脊髓灰质炎减毒活疫苗黏膜免疫的影响

Effect of bifidobacterium on mucosal immunity of bivalent oral poliomyelitis vaccine of types Ⅰ+ Ⅲ

目的探讨双歧杆菌对Ⅰ+Ⅲ型二价脊髓灰质炎(简称脊灰)减毒活疫苗(bivalent oral poliovirus vaccine,bOPV)黏膜免疫的影响。方法给脊灰受体转基因小鼠接种2剂bOPV,间隔28 d,试验组小鼠在每剂bOPV接种前7 d灌胃双歧杆菌,同时对照组小鼠喂PBS。每剂疫苗接种后第3和第7天采集当天小鼠粪便样本,测定其中脊灰特异的IgA水平和排毒水平。在bOPV接种后检测小鼠细胞因子分泌水平和肠道淋巴结的淋巴细胞分群。结果第1剂和第2剂bOPV接种后的第3天,试验组小鼠脊灰特异的黏膜IgA水平均显著高于对照组(P<0.05或<0.01),且第1剂接种第3天,试验组小鼠IgA阳转率显著高于对照组(P<0.05)。试验组小鼠接种第1剂bOPV后第3天,Ⅰ型脊灰病毒排毒量显著低于对照组(P<0.01)。试验组小鼠在bOPV免疫后能激活更多的B淋巴细胞(P<0.000 1)和Th1通路的细胞因子IL-1、TNF-α(P<0.05)。结论双歧杆菌用于bOPV接种前可提高脊灰特异的黏膜免疫IgA分泌水平,且具有一定的减缓排毒作用。

Objective To investigate the effect of bifidobacterium on mucosal immunity induced by bivalent oral poliomyelitis vaccine(bOPV)of types Ⅰ+ Ⅲ. Methods Polio receptor transgenic mice were inoculated with two doses of b OPV at an interval of 28 d. The mice in test group were inoculated with bifidobacteria 7 d before each dose of vaccine by gavage,while those in control group were fed with PBS. Stool samples were collected from the mice on days 3 and 7 after each dose of vaccine,in which the levels of polio-specific IgA and virus shedding were measured. Cytokine secretion level and lymphocyte subsets in intestinal lymph nodes of mice were determined after vaccination. Results The levels of poliospecific mucosal IgA in mice in test group on day 3 after immunization with the first and the second doses of vaccine were significantly higher than those in control group(P< 0. 05 or P< 0. 01). The positive conversion rate of IgA of mice in test group on day 3 after immunization with the first dose of vaccine was significantly higher(P< 0. 05),while the virus shedding level of typeⅠwas significantly lower(P< 0. 01),than those in control group. The immunization with bOPV activated more B lymphocytes(P< 0. 000 1)and more Th1 pathway cytokines IL-1 and TNF-α(P< 0. 05)in mice in test group. Conclusion Application of bifidobacteria before immunization with bOPV increased the secretion level of poliospecific mucosal immune IgA,which showed a certain ability in slowing down the virus shedding.