摘要
目的：在杆状病毒昆虫细胞表达系统中表达结核分枝杆菌蛋白MPB64，并鉴定其免疫原性。方法：目的基因MPB64连接到pFastBac载体，获得pFastBac-MPB64质粒转化DH10 Bac感受态，通过Tn7转座片段将目的基因转座到Bacmid中，得到Bacmid-MPB64穿梭载体，脂质体包被后转染Sf 9细胞收获P1代病毒，重复转染Sf 9细胞三次获得高滴度的P4代病毒，收集细胞上清通过Q Sepharose FF和Ni亲和层析柱两步层析纯化得到目的蛋白MPB64。纯化的蛋白免疫BALB／c小鼠并检测血清中抗体滴度，ELISA检测MPB64蛋白刺激脾脏细胞产生IFN-γ的浓度，MTT法检测目的蛋白对免疫后小鼠脾脏细胞的增殖作用。结果：MPB64在昆虫细胞中成功表达，纯化后蛋白纯度达90％以上，蛋白产量为35 mg／L，纯化蛋白能有效刺激BALB／c小鼠产生抗体，提高小鼠脾脏细胞培养基中IFN-γ的含量，目的蛋白在0.2～100μg／ml之间对脾脏细胞有明显的促增殖作用。结论：成功在杆状病毒昆虫细胞表达系统中表达了具有免疫原性的MPB64蛋白，为生产结核病疫苗奠定了基础。
Objective：To express mycobacterium tuberculosis protein MPB 64 in baculovirus insect cell expression system ,and identify its immunogenicity.Methods：The target gene MPB64 was connected to pFastBac vector ,then the pFastBac-MPB64 plasmid which was harvested would transformed to DH10Bac competent,and the target gene was transposition into Bacmid by Tn7 transposase fragment,therefore Bacmid-MPB64 Shuttle vector was obtained.The shuttle vector was packaged by liposomes and transfected Sf 9 cells to harvest P1-generation virus ,then high titers of P4 generation virus was harvested by repeat transfected Sf 9 cells three times.The target protein MPB64 was purified from the supernatant by Q Sepharose FF and Ni affine chromatography ,which were used to immunize BALB/c mice.Antibody changes in serum would be detected ,and the proliferation of immunized mice spleen cells would be detected by MTT,detected the IFN-γsecretion by MPB64 stimulated spleen cells by ELISA method.Results： MPB64 successfully expressed in insect cells.The purity of target protein was over 90% and yield up to 35 mg/L after purification.Purified protein can effectively stimulate BALB/c mice to produce antibodies , increase the content of IFN-γmedium in mice spleen cells ,and significantly promoting proliferation in spleen cells between 0.2-100 μg/ml.Conclusion： MPB64 which has immunogenicity was successfully expressed in baculovirus insect cell expression system ,that open a new avenue for tuberculosis vaccine production.
出处
《中国免疫学杂志》
CAS
CSCD
北大核心
2014年第7期921-926,共6页
Chinese Journal of Immunology
基金
国家高新技术研究与发展计划项目(863项目)生物反应器重大专项资助(SQ2011AA100606)
2012年吉林省高层次创新创业引进人才项目
关键词
MPB64
杆状病毒表达系统
Sf
9细胞
结核分枝杆菌
MPB64
Baculovirus expression vector system
Sf 9 insect cells
Mycobacterium tuberculosis
