title: Galleria mellonella as an in vivo model for assessing the efficacy of antimicrobial agents against Enterobacter cloacae infection.
abstract: OBJECTIVE
  Enterobacter cloacae is a well-recognized nosocomial pathogen. Use of a rapid, in vivo infection model for E. cloacae that can determine the efficacy of antibiotic therapies could help facilitate screening for new treatments. Nonmammalian model systems of infection, such as Galleria mellonella, have significant logistical and ethical advantages over mammalian models.
  
  
  METHODS
  We utilized G. mellonella larvae to determine the utility of this infection model to study antibacterial efficacy. G. mellonella killing with heat-killed or live clinical isolates (E. cloacae GN1059 and GN0791) was tested. We also investigated the effect of postinoculation incubation temperature on the survival of infected larvae. The protection of administration of antibiotics to infected larvae was investigated. Finally, we determined the G. mellonella hemolymph burden of E. cloacae after administration of different antibiotics.
  
  
  RESULTS
  With live bacterial inocula, G. mellonella killing was significantly dependent on the number of E. cloacae cells injected in a dose-dependent manner. Further, we observed that survival was reduced with increasing the postinoculation temperature. Treatment of a lethal E. cloacae infection with antibiotics that had in vitro activity significantly prolonged the survival of larvae compared with treatment with antibiotics to which the bacteria were resistant. The therapeutic benefit arising from administration of antibiotic correlated with a reduced burden of E. cloacae cells in the hemolymph.
  
  
  CONCLUSIONS
  The G. mellonella infection model has the potential to be used to facilitate the in vivo study of host-pathogen interactions in E. cloacae and the efficacy of antibacterial agents.
authors: Department of Infectious Disease, the First Affiliated Hospital of Anhui Medical University, Hefei, China.
authors: Hai-Fei
authors: HF
authors: Yang
authors: Intensive Care Unit, Anhui Provincial Hospital, Hefei, China.
authors: Ai-Jun
authors: AJ
authors: Pan
authors: Department of Infectious Disease, the First Affiliated Hospital of Anhui Medical University, Hefei, China.
authors: Li-Fen
authors: LF
authors: Hu
authors: Institute of Bacterium Resistance, Anhui Medical University, Hefei, China; Anhui Center for Surveillance of Bacterial Resistance, Hefei, China.
authors: Yan-Yan
authors: YY
authors: Liu
authors: Department of Infectious Disease, the First Affiliated Hospital of Anhui Medical University, Hefei, China.
authors: Jun
authors: J
authors: Cheng
authors: Department of Infectious Disease, the First Affiliated Hospital of Anhui Medical University, Hefei, China; Institute of Bacterium Resistance, Anhui Medical University, Hefei, China; Anhui Center for Surveillance of Bacterial Resistance, Hefei, China.
authors: Ying
authors: Y
authors: Ye
authors: Department of Infectious Disease, the First Affiliated Hospital of Anhui Medical University, Hefei, China; Institute of Bacterium Resistance, Anhui Medical University, Hefei, China; Anhui Center for Surveillance of Bacterial Resistance, Hefei, China; Department of Infectious Disease, Chaohu Hospital of Anhui Medical University, Hefei, China. Electronic address: younghaifei@gmail.com.
authors: Jia-Bin
authors: JB
authors: Li
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000494:pharmacology*; D058491:Bacterial Load; D001431:Bacteriological Techniques / Q000379:methods*; D001681:Biological Assay; D004195:Disease Models, Animal; D016972:Enterobacter cloacae / Q000187:drug effects*; D004756:Enterobacteriaceae Infections / Q000382:microbiology*; D004772:Entomology / Q000379:methods*; D006458:Hemolymph / Q000382:microbiology; D007814:Larva / Q000187:drug effects; D007915:Lepidoptera / Q000382:microbiology*; D016019:Survival Analysis
chemical_list: D000890:Anti-Infective Agents
keywords: Enterobacter cloacae; antibacterial; antimicrobial; drug resistance; insect infection model