Katarzyna Okurowska, Peter N Monk, Esther Karunakaran
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引用次数: 0
Abstract
Introduction. Bacterial keratitis, particularly caused by Pseudomonas aeruginosa, is challenging to treat because of multi-drug tolerance, often associated with the formation of biofilms. Antibiotics in development are typically evaluated against planktonic bacteria in a culture medium, which may not accurately represent the complexity of infections in vivo.Hypothesis/Gap Statement. Developing a reliable, economic ex vivo keratitis model that replicates some complexity of tissue infections could facilitate a deeper understanding of antibiotic efficacy, thus aiding in the optimization of treatment strategies for bacterial keratitis.Methodology. Here we investigated the efficacy of three commonly used antibiotics (gentamicin, ciprofloxacin and meropenem) against Pseudomonas aeruginosa cytotoxic strain PA14 and invasive strain PA01 using an ex vivo porcine keratitis model.Results. Both strains of P. aeruginosa were susceptible to the MIC of the three tested antibiotics. However, significantly higher concentrations were necessary to inhibit bacterial growth in the minimum biofilm eradication concentration (MBEC) assay, with both strains tolerating concentrations greater than 512 mg l-1 of meropenem. When MIC and higher concentrations than MBEC (1024 mg l-1) of antibiotics were applied, ciprofloxacin exhibited the highest potency against both P. aeruginosa strains, followed by meropenem, while gentamicin showed the least potency. Despite this, none of the antibiotic concentrations used effectively cleared the infection, even after 18 h of continuous exposure.Conclusions. Further exploration of antibiotic concentrations and aligning dosing with clinical studies to validate the model is needed. Nonetheless, our ex vivo porcine keratitis model could be a valuable tool for assessing antibiotic efficacy.
期刊介绍:
We publish high-quality original research on bacteria, fungi, protists, archaea, algae, parasites and other microscopic life forms.
Topics include but are not limited to:
Antimicrobials and antimicrobial resistance
Bacteriology and parasitology
Biochemistry and biophysics
Biofilms and biological systems
Biotechnology and bioremediation
Cell biology and signalling
Chemical biology
Cross-disciplinary work
Ecology and environmental microbiology
Food microbiology
Genetics
Host–microbe interactions
Microbial methods and techniques
Microscopy and imaging
Omics, including genomics, proteomics and metabolomics
Physiology and metabolism
Systems biology and synthetic biology
The microbiome.