Skip to Main content Skip to Navigation
New interface
Journal articles

Inhibition of the β-Lactamase Bla Mab by Avibactam Improves the In Vitro and In Vivo Efficacy of Imipenem against Mycobacterium abscessus

Abstract : Mycobacterium abscessus pulmonary infections are treated with a macrolide (clarithromycin or azithromycin), an aminoglycoside (amikacin), and a β-lactam (cefoxitin or imipenem). The triple combination is used without any β-lactamase inhibitor, even though Mabscessus produces the broad-spectrum β-lactamase BlaMab We determine whether inhibition of BlaMab by avibactam improves the activity of imipenem against M. abscessus The bactericidal activity of drug combinations was assayed in broth and in human macrophages. The in vivo efficacy of the drugs was tested by monitoring the survival of infected zebrafish embryos. The level of BlaMab production in broth and in macrophages was compared by quantitative reverse transcription-PCR and Western blotting. The triple combination of imipenem (8 or 32 μg/ml), amikacin (32 μg/ml), and avibactam (4 μg/ml) was bactericidal in broth (<0.1% survival), with 3.2- and 4.3-log10 reductions in the number of CFU being achieved at 72 h when imipenem was used at 8 and 32 μg/ml, respectively. The triple combination achieved significant intracellular killing, with the bacterial survival rates being 54% and 7% with the low (8 μg/ml) and high (32 μg/ml) dosages of imipenem, respectively. In vivo inhibition of BlaMab by avibactam improved the survival of zebrafish embryos treated with imipenem. Expression of the gene encoding BlaMab was induced (20-fold) in the infected macrophages. Inhibition of BlaMab by avibactam improved the efficacy of imipenem against M. abscessusin vitro, in macrophages, and in zebrafish embryos, indicating that this β-lactamase inhibitor should be clinically evaluated. The in vitro evaluation of imipenem may underestimate the impact of BlaMab, since the production of the β-lactamase is inducible in macrophages.
Document type :
Journal articles
Complete list of metadata
Contributor : Vincent LE MOIGNE Connect in order to contact the contributor
Submitted on : Sunday, May 29, 2022 - 9:01:49 PM
Last modification on : Tuesday, October 18, 2022 - 4:30:35 AM
Long-term archiving on: : Tuesday, August 30, 2022 - 6:16:43 PM


Files produced by the author(s)



Anne-Laure Lefebvre, Vincent Le Moigne, Audrey Bernut, Carole Veckerlé, Fabrice Compain, et al.. Inhibition of the β-Lactamase Bla Mab by Avibactam Improves the In Vitro and In Vivo Efficacy of Imipenem against Mycobacterium abscessus. Antimicrobial Agents and Chemotherapy, 2017, 61 (4), pp.e02440-16. ⟨10.1128/aac.02440-16⟩. ⟨hal-03680922⟩



Record views


Files downloads