摘要
罗非鱼源无乳链球菌GD201008-001对小鼠的致死率极高,极低数量的细菌(10 CFU/只)攻毒12 h后小鼠即表现出临床症状,24 h内全部死亡。这一现象与人类感染链球菌后产生的中毒性休克综合征(STSS)症状相似,STSS是由链球菌超抗原引起,故推测GD201008-001在感染小鼠的过程中可能会分泌某种超抗原(superantigen,SAg)。通过对该菌基因组进行超抗原的生物信息学分析,并采用体外淋巴细胞增殖试验(MTS法)来检测是否存在超抗原物质。结果表明,在GD201008-001基因组中不含已知的超抗原或超抗原样蛋白基因,同时无乳链球菌在体外培养环境下和体内小鼠感染过程中,均未释放可使淋巴细胞明显增殖的超抗原物质,该强毒株对小鼠高致死率的致病机理仍需我们进一步的探索。
The lethality rate of tilapia-derived S.agalactiae GD201008-001 in mice is extremely high.After 12 hours of attack with a very low number of-bacteria (10 CFU/body),the mice begin to show various clinical symptoms,and subsequently all died within 24 hours.This phenomenon is similar to the,symptoms of Streptococcal toxic shock syndrome (STSS)produced by humans infected with hemolytic streptococci,and STSS is caused by streptococcal superantigens;therefore,it is speculated that GD201008-001 infectedrats may secrete a certain superantigeninthe process.We performed a bioinformatic analysis of superantigens on the bacterial genome and used an in vitro lymphocyte proliferation assay to detect the presence of superantigen substances.The results showed that no known superantigen or superantigen-like protein gene was found in the GD201008-001 genome,and that no S.agalactiae released in the in vitro culture medium,and thein vivo mouse infection release no superantigen either.The pathogenic mechanism of the virulent strains on the high lethality of mice still requires further exploration.
作者
高婷婷
刘广锦
姚火春
GAO Tingting;LIU Guangjin;YAO Huochun(College of Veterinary Medicine,Nanjing Agricultural University,Nanjing 210095,China)
出处
《畜牧与兽医》
北大核心
2018年第12期68-72,共5页
Animal Husbandry & Veterinary Medicine
基金
国家自然科学基金青年科学基金(31502085)
江苏省自然科学基金青年科学基金(BK20140703)
江苏省优势学科项目(PAPD)
关键词
无乳链球菌
超抗原
淋巴细胞
淋巴细胞增殖试验
Streptococcus agalactiae
superantigen
lymphocyte
lymphocyte proliferation assay
