大蜡螟感染模型在肺炎克雷伯菌毒力研究中的应用  

GaUeria mellonella infection model for evaluating the virulence of Klebsiella pneumoniae

作　　者：汤怡颖 胡仁静[1] Tang Yiying;Hu Renting(Department of Laboratory Medicine,Wuxi No.2 People＇s Hospital,Wuxi 214000,China)

机构地区：[1]无锡市第二人民医院检验科,214002

出　　处：《中华微生物学和免疫学杂志》2018年第8期611-615,共5页Chinese Journal of Microbiology and Immunology

基　　金：无锡市科技支撑项目（CSE31N1602）

摘　　要：目的 评价肝脓肿相关肺炎克雷伯菌的大蜡螟感染模型,建立肺炎克雷伯菌毒力检测的新方法.方法 收集无锡市第二人民医院2016年1月至2017年12月分离肝脓肿相关肺炎克雷伯菌12株,痰液、尿液中分离的20株肺炎克雷伯菌作为经典非高毒力肺炎克雷伯菌（经典组）;所有菌株进行黏液丝试验,PCR检测肺炎克雷伯菌常见的高毒力的荚膜血清型（K1、K2、K5、K16、K20、K54、K57）,大蜡螟毒力试验测定同一时间段不同血清荚膜型的80％致死量（80％lethal dose,LD80）以及在同一浓度下达到80％幼虫死亡的时间（80％lethal time,LT80）.结果 肝脓肿组荚膜血清型主要为K1、K2、K5、K20、K57,分别占41.7％（5/12）、8.3％（1/12）、8.3％（1/12）、8.3％（1/12）、33.4％（4/12）;经典组未检出高毒力荚膜血清型.肝脓肿组黏液丝试验阳性率为75％（9/12）,经典组的黏液丝试验的阳性率为10％（2/20）.大蜡螟毒力试验显示在浓度为1×105 CFU/ml至1×108 CFU/ml时,不同的菌株对大蜡螟幼虫的致死率呈现浓度依赖性,接种12 h后,K1、K57组的死亡幼虫数量显著高于K2、K5、K20组及经典组;接种96 h肝脓肿组的LD80分别为：1×106 CFU/ml（K1、K57）;1×107 CFU/ml（K2、K5、K20）.结论 我院分离的肝脓肿相关肺炎克雷伯菌均为高毒力菌株,大蜡螟模型菌液接种后12 h可进行肺炎克雷伯菌毒力的检测.Objective To establish a C, alleria rnellonella model of liver abscess-related Klebsiella pneumoniae （ K. pneumoniae ） infection and to evaluate its feasibility for virulence detection . Methods Twelve liver abscess-related K. pneumoniae strains were collected in Wuxi No. 2 People＇s Hospital from Janu- ary 2016 to December 2017. Twenty K. pneumoniae strains isolated from sputum and urine samples were used as classic strains. All isolates were analyzed by String test. Common capsular serotypes （ K1, K2, K5, K16, K20, K54 and K57） of highly virulent K. pneumoniae strains were detected by PCR. Virulence test was performed to measure 80% lethal doses （ LDs0 ） of different serotypes in the same time period and the lethal time for 80% of larvae （ LTs0 ） at the same concentration. Results The 12 strains of liver abscess-re- lated K. pneumoniae belonged to five serotypes, which were K1 （41.7%, 5/12）, K2 （8.3%, 1/12）, K5 （ 8.3 %, 1/12）, K20 （ 8.3 %, 1/12） and K57 （ 33.4%, 4/12 ）. High-virulence serotypes were not detec- ted in the classic group. The positive rates of String test in the liver abscess group and the classic group were 75% and 10% （2/20）, respectively. Results of the virulence test showed that when the concentration ranged from 1×10^5 CFU/ml to 1×10^8 CFU/ml, the lethal effects of different strains on Galleria mellonella larvae were in a concentration dependent manner. Twelve hours after infection, the numbers of dead larvae in K1 and K57 serotype groups were significantly higher than those in K2, KS, K20 and classic groups. The LD80 values of the liver abscess group at 96 hours after infection were as follows ： 1×10^6 CFU/ml （ K1, K57 ） and 1×10^7 CFU/ml （K2, K5, K20）. Conclusion The liver abscess-related K. pneumoniae isolates are all highly virulent strains. The virulence of K. pneumoniae can be detected at 12 hours after infection of Galleria mellonella.

关 键 词：肺炎克雷伯菌 荚膜血清型 毒力 黏液丝试验 大蜡螟 

分 类 号：R446.5[医药卫生—诊断学]