幽门螺杆菌尿素酶减毒鼠伤寒杆菌疫苗诱导小鼠粘膜免疫应答的研究

目的:观察口服减毒鼠伤寒杆菌活菌重组疫苗后小鼠的粘膜免疫应答状况。方法:将已构建成功的表达幽门螺杆菌(H.pylori)尿素酶B亚单位(UreB)的重组减毒鼠伤寒杆菌SL3261/pTC01-UreB口服免疫Balb/c小鼠,12周后检测肠液和血清中的特异性抗体反应。结果:疫苗组小鼠的肠液和血清中可分别检测到针对UreB的特异性抗体IgA和IgG,病理学检查显示疫苗组小鼠较对照组小鼠胃粘膜炎症程度差异无统计学意义。结论:表达H.pyloriUreB的减毒鼠伤寒杆菌SL3261/pTC01-UreB能够诱导小鼠产生抗H.pylori的粘膜免疫,可用作抗H.pylori感染的口服疫苗。

Mucosal immune responses in mice to oral administration of attenuated Salmonella typhimurium expressing Helicobacter pylori urease B subunit

Objective:To evaluate whether attenuated Salmonella typhimurium producing Heli-cobacter pylori(H.pylori)urease subunit B(UreB)could induce mucosal immune responses against H.pylori infection.Methods:Attenuated Salmonella typhimurium SL3261was used as a live car-rier of plasmid pTC01-UreB,which encodes recombinant H.pylori UreB protein.Balb /c mice were immunizedith two oral doses of SL3261/pTC01-UreB at a3-week interval.Twelve weeks after immu-nization,anti-UreB IgA antibodies in the intestinal fluid and IgG antibodies in serum were deter-mined by ELISA.Re sults:The multiple oral immunizations with SL3261/pTC01-UreB could induce significantly H.pylori-specific mucosal IgA response as well as serum IgG responses.In addition,no obvious side effects for mice and no change in gastric inflammation were observed.Conclusion:The attenuated Salmonella typhimurium expressing H.pylori UreB may be used as oral vaccine a-gainst H.pylori infection.