中文摘要：

为研究表达产肠毒素性大肠埃希菌（ETEC）耐热性肠毒素STa与粘附素K99融合蛋白重组腺病毒rAd.STa-K99的免疫学特性,本实验将rAd.STa-K99经肌肉注射免疫小鼠,采用ELISA法分别检测了特异性IgG、SIgA、脾脏淋巴细胞增殖活性水平及CD4^＋、CD8^＋T淋巴细胞分型比值;并通过攻毒保护试验对其免疫效果进行评价.结果表明,免疫后小鼠特异性IgG、SIgA及脾脏淋巴细胞增殖活性水平显著升高;CD4＋/CD8＋值显著增大;动物攻毒保护率达到70％.结果表明rAd.STa-K99可以刺激小鼠机体产生较高水平的体液免疫、特异性细胞免疫和肠道粘膜免疫反应,并对小鼠提供有效保护.本实验为研制预防由ETEC引起的新生动物腹泻重组腺病毒疫苗奠定了基础.

英文摘要：

To evaluate the immunological characteristics of the recombinant adenovirus of rAd.STa-K99 expressing heat stable enterotoxin STa and adhesion K99 （STa-K99） fusion protein of enterotoxigenic Escherichia coli （ETEC）,the mice were intramuscularly immunized with the recombinant adenovirus,which were subsequently subjected to the ETEC challenging and the detections of humoral and cellular immune responses in the mice by ELISAs,respectively.The results showed that the titers of specific IgG and mucosal SIgA,proliferation of spleen lymphocyte and CD4^ ＋/CD8^ ＋ ratio significantly increased in immunized mice,and the immuoprotection rate reached to 70% for the mice.In conclusion,the rAd.STa-K99 was capable to elicit higher levels of humoral,mucosal,and cellular immune response in the mice,resulting in effectively protection of the mice against ETEC challenge,which demonstrated that adenovirus based recombinant virus was potential to be used as the vaccine for the newborn animals to prevent the diarrhea caused by ETEC infection.