插入结核抗原基因的重组痘苗病毒对结核分枝杆菌感染恒河猴模型的免疫保护性  

Immune protection of recombinant modified vaccinia virus Ankara with Ag85a and ESAT6 genes against Mycobacterium tuberculosis in infected rhesus macaques

作　　者：朱琳[1] 张群[1] 唐志佼[2] 张晶[2] 楼觉人[1] 

机构地区：[1]上海生物制品研究所有限责任公司,上海200052 [2]武汉大学ABSL-Ⅲ实验室,湖北武汉430071

出　　处：《中国生物制品学杂志》2015年第12期1245-1252,共8页Chinese Journal of Biologicals

摘　　要：目的重组亚牛痘病毒载体疫苗作为卡介苗的加强疫苗对结核病的免疫预防效果。方法将18只雌性中国恒河猴随机分为3组：BCG、BCG＋A和BCG＋AE组,每组6只,BCG＋A和BCG＋AE组用4×10^5 CFU的BCG经皮内初免后9周,分别用重组亚牛痘病毒MVA-Ag85a（A）或MVA-Ag85a-ESAT6（AE）,按1×10^9 PFU/只的剂量通过皮内加强免疫,BCG组仅用BCG免疫,另设未免疫组（Non-V组）：3只雄性中国恒河猴。加强免疫后9周,用结核分枝杆菌H37Rv株通过纤维支气管镜感染所有实验猴右肺下叶,攻毒剂量为41 CFU/只。经24周定期观察记录实验动物的临床表现,并采血进行血清学和免疫学检测。实验猴死亡或第24周处死后,全部尸检并进行病理学组织评分、组织细菌载量计数等检测。结果在实验终点,Non-V组仅存活1只实验猴,而免疫组3组的存活率均为100%。体外免疫试验中,经重组痘苗病毒免疫的试验组表现出抗原特异性IFNγ明显升高（P〈0.05）;组织病理总评分和细菌载量测定显示,BCG＋A组优于BCG组,而BCG＋AE与BCG组比较,未表现出优势。结论重组痘苗病毒MVA-Ag85a和MVA-Ag85a-ESAT6均能诱导抗原特异性IFNγ分泌,BCG＋A组较BCG单次免疫组有更好的免疫保护趋势;BCG＋AE组未表现出较BCG组更好的免疫保护效果。Objective To evaluate the preventive effect of recombinant modified vaccinia virus Ankara（MVA）as a boost vaccine of BCG. Methods Eighteen female Chinese rhesus macaques were randomly divided into three groups, i. e. BCG group, BCG ＋ A and BCG ＋ AE groups, six for each. Each macaque in BCG ＋ A and BCG ＋ AE groups were immunized i. d. with 4 × 10^5 CFU BCG, and boosted with 1 × 10^9 PFU recombinant MVA-Ag85a（A）and MVA-Ag85a-ESAT6（AE）9 weeks later, respectively. The macaques in BCG control group were only vaccinated with BCG, while another three macaques in Non-V control group were unimmunized. All the macaques were challenged with 41 CFU Mycobacterium tuberculosis H37 Rv through bronchofiberscope at lung right lower lobe 9 weeks after booster immunization and observed regularly for 24 weeks. The immunological, hematological and pathological parameters were detected and the clinical symptoms were monitored. The macaques which died within 24 weeks or were killed at week 24 after challenge were subjected to autopsy, scored for histopathology, and counted for bacterial load in tissue. Results At the endpoint of the study, there was only one macaque in Non-V group survived, while the survival rates in BCG, BCG ＋ A and BCG ＋ AE groups were 100%. In vitro immunization test showed that the antigen-specific IFNγ secretion levels in macaques boosted with recombinant vaccinia virus increased significantly（P〈0. 05）. As compared with BCG, BCG ＋ A showed advantage in decreasing the pathological score and bacterial load, while BCG ＋ AE showed no advantage. Conclusion Both MVAAg85 a and MVA-Ag85a-ESAT6 induced the secretion of antigen-specific IFNγ. BCG ＋ A showed a good trend of immune protection, while BCG ＋ AE showed no better immune effect, as compared with BCG alone.

关 键 词：结核 AG85A ESAT6 痘苗病毒 亚牛痘病毒Ankara株 恒河猴 

分 类 号：R378.911[医药卫生—病原生物学] R392-33[医药卫生—基础医学]