小鼠对结核分枝杆菌Ag85B-Esat6-HspX融合基因的免疫反应

目的研究结核分枝杆菌Ag85B-Esat6-HspX融合基因的免疫原性。方法将40只BALB/c小鼠随机分成4组,NS组、BCG组、pcDNA-HspX组和pcDNA-Ag85B-Esat6-HspX组,每组10只。BCG组只在0周时皮内注射卡介苗1次。NS组、pcDNA-HspX组及融合基因组分别于0、2、4周肌肉注射生理盐水和重组质粒DNA,共免疫3次。在免疫的第2周,4周及最后一次免疫后2周检测体血清中的总IgG水平。同时,最后一次免疫后2周,取脾细胞检测细胞免疫反应。结果构建的融合基因重组质粒DNA免疫动物后能产生针对结核杆菌特定抗原的特异性细胞免疫和体液免疫应答,具有较强的免疫原性。结论结核分枝杆菌Ag85B-Esat6-HspX融合基因可作为DNA疫苗进行保护作用的研究。

Immune Response to Recombinant Plasmid Expressing the Ag85BEsat6-HspX Fusion Protein in Mice

Objective To study immunogenicity of fusion gene Ag85B-Esat6-HspX of Mycobacterium tuberculosis.Methods Forty BALB/c mice were randomly divided into four groups（10 per group）： the plasmid pcDNA-HspX group,the pcDNA-Ag85B-Esat6-HspX plasmid group,the BCG group and the saline group.The immunization was repeated three times two weeks apart.A single dose of BCG（1×106 CFU/mouse） was injected subcutaneously.Mice in other three groups were administered intramuscularly in the hind limb.Total IgG levels were detected at 2,4 and 6 weeks after immunization.Meanwhile,cell-mediated immunity responses were examined two weeks after the final immunization as well.Result Mice immunized with recombinant plasmid expressing the Ag85B-Esat6-HspX fusion protein generated specific cellular and humoral immunologic response to the stimulation of Ag85B,Esat6 and HspX.Conclusion The fusion gene Ag85B-Esat6-HspX of Mycobacterium tuberculosis could be DNA vaccine to carry out the further research of protective efficacy.