幽门螺杆菌Hp1188蛋白的免疫保护效果

Immune protective effect of Hp1188 protein of Helicobacter pylori

目的研究幽门螺杆菌(Helicobacter pylori,H.pylori)重组Hp1188蛋白免疫反应性及口服免疫后对小鼠的保护效果,以探讨其在制备预防性疫苗中的价值。方法纯化H.pylori重组Hp1188蛋白,Western blot鉴定其免疫反应性。将纯化的重组Hp1188蛋白作为H.pylori抗原,ELISA法检测100例临床病例血清样本的相应抗体,并与尿素呼气试验(urea breath test,UBT)和快速尿素酶试验(rapid urease test,RUT)结果进行比较,评价其临床应用的可行性。将纯化的重组Hp1188蛋白免疫小鼠后,用H.pylori悉尼株1(Sydney strain 1,SS1)攻击感染,ELISA法检测小鼠血清和小肠黏液中抗Hp1188抗体(IgG、IgA和sIgA)产生情况;胃黏膜H.pylori培养、RUT、病理组织学检查观察H.pylori定植量及炎症情况。结果重组Hp1188蛋白纯化后纯度达90%,浓度为1.0 mg/mL。Western blot分析显示,该蛋白能被H.pylori患者血清识别。血清学结果显示,Hp1188抗体试剂检测的敏感性为93.8%,特异性为94.3%。经重组Hp1188蛋白免疫后,小鼠体内IgG、IgA、sIgA含量均明显高于PBS对照组(P<0.05),H.pylori活菌定植量、RUT及病理学检查指标均明显低于PBS对照组(P<0.05),对小鼠的保护率为70%。结论Hp1188蛋白对小鼠具有免疫保护作用,本研究为研制H.pylori相关疫苗提供了试验依据。

Objective To investigate the immunoreactivity of Hp1188 protein of Helicobacter pylori and its protection in mice immunized by oral route and explore its significance in preparation of preventive vaccine.Methods Recombinant Hp1188 protein of H.pylori was purified and identified for immunoreactivity by Western blot.The corresponding antibodies in 100 clinical serum samples were determined by ELISA using the purified recombinant HP1188 protein as H.pylori antigen,of which the results were compared with those of urea breath test(UBT)and rapid urease test(RUT)to evaluate the feasibility of clinical application of the protein.Mice were immunized with purified Hp1188 protein,challenged with H.pylori Sydney strain 1(SS1),and determined for IgG,IgA and sIgA against Hp1188 in serum and intestinal mucus by ELISA.H.pylori culture,RUT and pathological examination were performed on gastric mucosa of mice to observe the quantity of H.pylori colonization and inflammation.Results The purified Hp1188 protein reached a purity of 90%and a concentration of 1.0 mg/mL after purification,which could be recognized by sera of patients with H.pylolri infection as proved by Western blot.The results of serological test showed that the sensitivity and specificity of Hp1188 antibody kits were 93.8%and 94.3%respectively.The contents of IgG,IgA and sIgA in mice immunized with Hp1188 protein were significantly higher,while the count of clonized live H.pylori as well as the indexes in RUT and pathological examination were significantly lower,than those in PBS control group(each P<0.05),and the protective rate was 70%.Conclusion Hp1188 protein showed immune protective effect on mice,which provided an experimental basis for the development of H.pylori related vaccines.