title: In vivo assessment of drug efficacy against Mycobacterium abscessus using the embryonic zebrafish test system.
abstract: Mycobacterium abscessus is responsible for a wide spectrum of clinical syndromes and is one of the most intrinsically drug-resistant mycobacterial species. Recent evaluation of the in vivo therapeutic efficacy of the few potentially active antibiotics against M. abscessus was essentially performed using immunocompromised mice. Herein, we assessed the feasibility and sensitivity of fluorescence imaging for monitoring the in vivo activity of drugs against acute M. abscessus infection using zebrafish embryos. A protocol was developed where clarithromycin and imipenem were directly added to water containing fluorescent M. abscessus-infected embryos in a 96-well plate format. The status of the infection with increasing drug concentrations was visualized on a spatiotemporal level. Drug efficacy was assessed quantitatively by measuring the index of protection, the bacterial burden (CFU), and the number of abscesses through fluorescence measurements. Both drugs were active in infected embryos and were capable of significantly increasing embryo survival in a dose-dependent manner. Protection from bacterial killing correlated with restricted mycobacterial growth in the drug-treated larvae and with reduced pathophysiological symptoms, such as the number of abscesses within the brain. In conclusion, we present here a new and efficient method for testing and compare the in vivo activity of two clinically relevant drugs based on a fluorescent reporter strain in zebrafish embryos. This approach could be used for rapid determination of the in vivo drug susceptibility profile of clinical isolates and to assess the preclinical efficacy of new compounds against M. abscessus.
authors.affiliation: Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, CNRS UMR5235, Université Montpellier 2, Montpellier, France.
authors.forename: Audrey
authors.initials: A
authors.lastname: Bernut
authors.affiliation: EA3647-EPIM, UFR des Sciences de La Santé, Université de Versailles St. Quentin, Montigny le Bretonneux, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Le Moigne
authors.affiliation: Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, CNRS UMR5235, Université Montpellier 2, Montpellier, France.
authors.forename: Tiffany
authors.initials: T
authors.lastname: Lesne
authors.affiliation: Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, CNRS UMR5235, Université Montpellier 2, Montpellier, France.
authors.forename: Georges
authors.initials: G
authors.lastname: Lutfalla
authors.affiliation: EA3647-EPIM, UFR des Sciences de La Santé, Université de Versailles St. Quentin, Montigny le Bretonneux, France.
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Herrmann
authors.affiliation: Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, CNRS UMR5235, Université Montpellier 2, Montpellier, France Inserm, DIMNP, Montpellier, France laurent.kremer@univ-montp2.fr.
authors.forename: Laurent
authors.initials: L
authors.lastname: Kremer
mesh_terms: D000818:Animals; D001922:Brain Abscess / Q000188:drug therapy / Q000382:microbiology; D017291:Clarithromycin / Q000627:therapeutic use*; D024901:Drug Resistance, Multiple, Bacterial; D004359:Drug Therapy, Combination; D015378:Imipenem / Q000627:therapeutic use*; D007814:Larva / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008826:Microbial Sensitivity Tests; D009165:Mycobacterium Infections, Nontuberculous / Q000188:drug therapy* / Q000382:microbiology; D009170:Nontuberculous Mycobacteria / Q000187:drug effects*; D061848:Optical Imaging / Q000379:methods*; D015027:Zebrafish / Q000382:microbiology
chemical_list: D015378:Imipenem; D017291:Clarithromycin