OipA DNA疫苗抗螺旋形和球形幽门螺杆菌免疫保护作用及其机制  

The immunological protection and mechanism of OipA DNA vaccine protecting against the infection of helical and coccoid forms of Helicobacter pylori

作　　者：佘菲菲[1] 吴小茜[1] 陈豪[1] 陈月秀[1] 

机构地区：[1]福建医科大学分子医学微生物学实验室,福州350004

出　　处：《中华微生物学和免疫学杂志》2006年第4期328-333,共6页Chinese Journal of Microbiology and Immunology

基　　金：福建省自然科学基金重大项目(2001F003)

摘　　要：目的探讨pcDNA3．1-oipA DNA疫苗在抗螺旋形与球形幽门螺杆菌(Hp)感染中的作用及其机制。方法抽提并纯化可表达OipA蛋白的重组质粒pcDNA3．1-oipA,以金粉包裹后,用基因枪接种BALB／c小鼠,5μg/只,接种2次,以pcDNA3．1(空载组)作对照。对免疫小鼠进行:(1)免疫保护实验: 于末次免疫后8周,分别给予螺旋形及球形HpSS1攻击4次,于末次攻击4周后取胃组织做细菌学(组织尿素酶试验、细菌培养)及病理学检测。(2)小鼠免疫指标检测:分别于末次免疫后2、8、12周采集小鼠血清,用ELISA法检测其抗Hp OipA IgA、IgG、IgG1抗体。于末次免疫后12周,取脾细胞,用ELISA法检测 IFN-γ、IL-2的含量;用流式细胞术检测CD4^+／CD8^+T淋巴细胞的比值。结果以螺旋形及球形Hp攻击的免疫小鼠,快速尿素酶实验阳性率分别为20％和10％;细菌培养阳性率分别为60％和50％,与空载组比较P<0．05。空载组小鼠胃黏膜均出现轻度或重度糜烂,而以螺旋形Hp攻击的实验组小鼠50％胃黏膜正常,以球形Hp攻击的实验组小鼠60％胃黏膜正常,与空载组比较P<0．050小鼠免疫指标检测结果:免疫后8周,产生了抗OipA的特异性IgA、IgG、IgG1抗体,抗体滴度比对照组高2倍以上;脾细胞中 CD4^+／CD8^+T淋巴细胞的比值升高;脾细胞培养上清液IFN-γ、IL-2的含量明显高于对照组(P<0．05)。结论pcDNA3．1-oipA DNA疫苗能有效诱导免疫小鼠产生体液与细胞免疫并使小鼠兼具一定的抗螺旋形及球形Hp感染的能力。Objective To investigate the immunological protection and mechanism induced by DNA vaccine expressing Hdlicobacter pylori（Hp） OipA. Methods The recombinant plasmid peDNA3.1-oipA was inoculated to BALB/e mice. Eight weeks after last immunization, the part of immunized mice was given orogastricly with helical or coccoid forms of Hp Sydney strain four times （0.5 × 10^9 CFU/ml, 0.5 ml each mouse）. Four weeks after challenge, mice were sacrificed, histological change and the colonization of Hp in the gastric mucesa were detected by urease test and culture of Hp. Detection of immunological index of iunnunized mice. The sera of immunized mice were collected at 2, 8, 12 weeks after the last immunization. Titer of anti Hp OipA IgA, IgG, IgG1 antibodies was detected by ELISA to understand the level of generated humoral immunity. Twelve weeks after last immunization, the splenic cells were raked and detected the contents of IFN-γ, IL-2 by ELISA. The ratio of CD4^＋/CD8^＋ T lymphocyte was detected by flow cytometry to understand the level of generated cellular immunity. Results The positive rates of urease test of gastric mucesa were as follow： the experimental group challenged with helical forms of Hp 20% （2/10）, the experimental group challenged with coccoid forms of Hp 10%（1/10）. The positive rates of cultures of Hp were as follow： the experimental group challenged with helical forms of Hp 60% （6/10）, the experimental group challenged with coccnid forms of Hp 50%（5/10）, lower than the control group（ P 〈0.05）. The different degree of erosion was observed in control group, but 50% and 60% of gastric mucosa were normal in immunized mice challenged with helical or coccoid forms of Hp（P 〈0.05）. Eight weeks after last immunization, BALB/c mice inoculated with pcDNA3.1-oipA DNA vaccine had been induced anfi-OipA IgA, IgG, IgG1 antibodies, titers of antibodies were two times highs than the control group. The ratio of CD4^＋/CD8^＋ T lymphocyte was improved. The contents of IFN-γ, IL

关 键 词：幽门螺杆菌 OIPA DNA疫苗 免疫保护 

分 类 号：R392[医药卫生—免疫学]