作　　者： ; ; ; ; ; ; ; ; (施远祥）; (阿曼古丽）;

机构地区： 中国农业科学院哈尔滨兽医研究所兽医生物技术国家重点实验室

出　　处： 《畜牧兽医学报》 2008年第4期466-471,共6页

摘　　要： 分泌性蛋白Ag85B、MPB64和ESAT-6为Mycobacterium bovis的主要保护性抗原,在诱导机体免疫反应和抵抗感染中发挥重要作用。本研究以pcDNA3.1(+)为载体,构建了由上述3种抗原基因构成的不同疫苗:3基因融合(pcDNA-MPB64-Ag85B-ESAT-6,pCMAE)DNA疫苗和三价(pcDNA-Ag85B+pcDNA-MPB64+pcDNA-ESAT-6)DNA疫苗,评价各种DNA疫苗诱导的体液免疫、细胞免疫及以BCG攻毒后的免疫保护水平。试验结果表明,多基因融合DNA疫苗免疫后的小鼠血清抗体水平、淋巴细胞增殖(SI值)、gamma interferon(IFN-γ)和interleukin-2(IL-2)水平明显高于其他各组(P<0.05),攻毒保护效果也优于多价DNA疫苗,达到了BCG疫苗的免疫保护水平,表明本研究制备的融合DNA疫苗具有良好的应用前景。 Mycobacterium boris is the etiological agent of bovine tuberculosis （BT）. The secretory proteins Ag85B, MPB64 and ESAT-6 are the major immunogenic antigens of M. boris, and they play important roles in inducing immune responses that confer resistance against infection. In the present study, using pcDNA3.1（＋） as vector, various DNA vaccines were constructed with the genes encoding the three antigens as follows; fusion of three genes （pcDNA-MPB64/Ag85B/ES- AT-6, pcDNA-MAE） and trivalent combinations （pcDNA-Ag85B ＋ pcDNA-MPB64 ＋ pcDNA- ESAT-6）. The immune efficacy of the DNA vaccines were evaluated based on serum antibody titers, lymphocyte proliferation assay and content of cytokine （interferon-γ and interleukin-2）titers. Protective efficacy following challenge with M. boris Bacille Calmette-Guerin （BCG） was evaluated based on lung tissue bacterial loads and histopathologic changes. The data demonstrated that immunization with fusion DNA vaccines （three genes） resulted in significantly higher serum antibody levels, lymphocyte proliferation （SI） values, IFN-γ and IL-2 levels than immunization with polyvalent DNA vaccines （P 〈0.05）. Additionally, fusion DNA vaccines provided superior protection than polyvalent DNA vaccines following BCG challenge. The protective efficacy of the fusion DNA vaccines was equivalent to that of the BCG vaccine, suggesting that fusion DNA vaccines provide a promising approach for the prevention of BT.

关 键 词： 牛分枝杆菌 融合 疫苗 多价 疫苗

领　　域： [农业科学] [农业科学] [农业科学]