title: High-sensitivity MALDI-MRM-MS imaging of moxifloxacin distribution in tuberculosis-infected rabbit lungs and granulomatous lesions.
abstract: MALDI-MSI is a powerful technology for localizing drug and metabolite distributions in biological tissues. To enhance our understanding of tuberculosis (TB) drug efficacy and how efficiently certain drugs reach their site of action, MALDI-MSI was applied to image the distribution of the second-line TB drug moxifloxacin at a range of time points after dosing. The ability to perform multiple monitoring of selected ion transitions in the same experiment enabled extremely sensitive imaging of moxifloxacin within tuberculosis-infected rabbit lung biopsies in less than 15 min per tissue section. Homogeneous application of a reference standard during the matrix spraying process enabled the ion-suppressing effects of the inhomogeneous lung tissue to be normalized. The drug was observed to accumulate in granulomatous lesions at levels higher than that in the surrounding lung tissue from 1.5 h postdose until the final time point. MALDI-MSI moxifloxacin distribution data were validated by quantitative LC/MS/MS analysis of lung and granuloma extracts from adjacent biopsies taken from the same animals. Drug distribution within the granulomas was observed to be inhomogeneous, and very low levels were observed in the caseum in comparison to the cellular granuloma regions. In this experiment the MALDI-MRM-MSI method was shown to be a rapid and sensitive method for analyzing the distribution of anti-TB compounds and will be applied to distribution studies of additional drugs in the future.
authors.affiliation: Novartis Institutes for BioMedical Research, Basel, Switzerland. brendan.prideaux@novartis.com
authors.forename: Brendan
authors.initials: B
authors.lastname: Prideaux
authors.forename: Véronique
authors.initials: V
authors.lastname: Dartois
authors.forename: Dieter
authors.initials: D
authors.lastname: Staab
authors.forename: Danielle M
authors.initials: DM
authors.lastname: Weiner
authors.forename: Anne
authors.initials: A
authors.lastname: Goh
authors.forename: Laura E
authors.initials: LE
authors.lastname: Via
authors.forename: Clifton E
authors.initials: CE
authors.lastname: Barry
authors.forename: Markus
authors.initials: M
authors.lastname: Stoeckli
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics*; D001372:Aza Compounds / Q000493:pharmacokinetics*; D005260:Female; D024841:Fluoroquinolones; D015769:Granuloma, Respiratory Tract / Q000378:metabolism* / Q000473:pathology; D008168:Lung / Q000378:metabolism / Q000382:microbiology* / Q000473:pathology; D057054:Molecular Imaging / Q000379:methods* / Q000592:standards; D000077266:Moxifloxacin; D011804:Quinolines / Q000493:pharmacokinetics*; D011817:Rabbits; D012015:Reference Standards; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods* / Q000592:standards; D014397:Tuberculosis, Pulmonary / Q000378:metabolism* / Q000473:pathology
chemical_list: D000900:Anti-Bacterial Agents; D001372:Aza Compounds; D024841:Fluoroquinolones; D011804:Quinolines; D000077266:Moxifloxacin