摘要目的 以乙基亚硝基脲(ENU)诱变技术建立小鼠葡萄球菌性角膜感染模型,探讨其主要条件致病菌的生物学特性.方法 以ENU(150mg/kg)腹腔注射10周龄雄性C57BL/6小鼠,60d后与其同品系雌性小鼠配种,F1代小鼠中发现角膜混浊小鼠,以具有角膜混浊表型小鼠与C57BL/6小鼠回交的方式繁育.对角膜混浊小鼠角膜感染菌进行分离、培养、纯化、鉴定,并使用不同抗生素进行药物敏感试验.结果 建立了稳定的小鼠葡萄球菌性角膜感染模型.从自发性角膜混浊(B6-Co)小鼠眼部成功分离纯化了松鼠葡萄球菌,筛选出了对该菌敏感及耐药的抗生素.对该菌敏感的抗生素有阿奇霉素、克林霉素、氯霉素、庆大霉素、利福平、四环素、阿米卡星、复方新诺明、米诺环素、左氟沙星、头孢噻吩、头孢噻肟、呋喃唑酮;对该菌耐药的抗生素有头孢西丁、青霉素、氨苄西林、新生霉素;属于中间态的抗生素为呋喃妥因.结论 C57BL/6小鼠葡萄球菌性角膜感染模型为自发性动物模型,系凝固酶阴性葡萄球菌感染所致,以松鼠葡萄球菌为主.

abstractsBackground An ethylnitrosourea(ENU)-induced mutant strain C57BL/6 mouse model has been established by our research group.This model is proved to have the spontaneous phenotype of corneal opacity and the typical pathological process similar to human keratitis.Therefore,this model is expected to be a good animal model in the research of the mechanism,hereditary property,and development of drugs for corneal infectious diseases.Objective The present study is to investigate the biological features of opportunistic pathogens using a mouse Staphylococcus-infected corneal model(C57BL/6 mouse) induced by N-ethyl-N-nitrosourea(ENU),and offers an evidence of stability in this animal model.Methods Ten-week-old male C57BL/6 mice were treated with ENU at 150mg/kg by intraperitoneal injection,and then mated with female mice after 60 days.Corneal opacity mutant mice in the F1 generation were selected to backcross with C57BL/6 mice.The bacteria were isolated from the eyeballs of the mutants and cultivated,purified and identified.Drug sensitivity assay was carried out to screen for effective antibiotics for clinic medical care.Results The staphylococcus-infected corneal mouse model(B6-Co) was established successfully,and the Staphylococcus sciuri strain was separated and purified,and then the sensitive antibiotics were distinguished from resistant ones.The sensitive drugs for Staphylococcus sciuri included azithromycin,clindamycin,chloramphenicol,gentamicin,rifampicin,tetracycline,amikacin,sulfamethoxazole compound sinomin,minocycline,levofloxacin,cephalothin,cefotaxime,and furazolidone;whereas this Staphylococcal strain was resistant to cefoxitin,penicillin,ampicillin,novobiocin.Nitrofurantoin showed an intermediate sensitivity.Conclusion The C57BL/6 mouse model is a spontaneous-derived animal model that is infected by coagulase-negative staphylococci,among which the most abundant strain is Staphylococcus sciuri.