Bacteria tracking by in vivo magnetic resonance imaging

Background: Different non-invasive real-time imaging techniques have been developed over the last decades to study bacterial pathogenic mechanisms in mouse models by following infections over a time course. In vivo investigations of bacterial infections previously relied mostly on bioluminescence im...

Authors: Hörr, Verena
Tuchscherr de Hauschopp, Lorena
Hüve, Jana
Nippe, Nadine
Loser, Karin
Glyvuk, Nataliya
Tsytsyura, Yaroslav
Holtkamp, Michael
Sunderkötter, Cord
Karst, Uwe
Klingauf, Jürgen
Peters, Georg
Löffler, Bettina
Faber, Cornelius
Division/Institute:FB 05: Medizinische Fakultät
FB 12: Chemie und Pharmazie
Document types:Article
Media types:Text
Publication date:2013
Date of publication on miami:21.02.2014
Modification date:16.04.2019
Edition statement:[Electronic ed.]
Source:BMC Biology 11 (2013) 63
Subjects:Bacterial cell labeling; Bacteria tracking; Infectious diseases; Mouse models of infection; Cellular and molecular MRI
DDC Subject:610: Medizin und Gesundheit
License:CC BY 2.0
Language:English
Notes:Finanziert durch den Open-Access-Publikationsfonds 2013/2014 der Deutschen Forschungsgemeinschaft (DFG) und der Westfälischen Wilhelms-Universität Münster (WWU Münster).
Format:PDF document
URN:urn:nbn:de:hbz:6-24319454654
Permalink:http://nbn-resolving.de/urn:nbn:de:hbz:6-24319454654
Other Identifiers:DOI: 10.1186/1741-7007-11-63
Digital documents:1741-7007-11-63.pdf

Background: Different non-invasive real-time imaging techniques have been developed over the last decades to study bacterial pathogenic mechanisms in mouse models by following infections over a time course. In vivo investigations of bacterial infections previously relied mostly on bioluminescence imaging (BLI), which is able to localize metabolically active bacteria, but provides no data on the status of the involved organs in the infected host organism. In this study we established an in vivo imaging platform by magnetic resonance imaging (MRI) for tracking bacteria in mouse models of infection to study infection biology of clinically relevant bacteria. Results: We have developed a method to label Gram-positive and Gram-negative bacteria with iron oxide nano particles and detected and pursued these with MRI. The key step for successful labeling was to manipulate the bacterial surface charge by producing electro-competent cells enabling charge interactions between the iron particles and the cell wall. Different particle sizes and coatings were tested for their ability to attach to the cell wall and possible labeling mechanisms were elaborated by comparing Gram-positive and -negative bacterial characteristics. With 5-nm citrate-coated particles an iron load of 0.015 ± 0.002 pg Fe/bacterial cell was achieved for Staphylococcus aureus. In both a subcutaneous and a systemic infection model induced by iron-labeled S. aureus bacteria, high resolution MR images allowed for bacterial tracking and provided information on the morphology of organs and the inflammatory response. Conclusion: Labeled with iron oxide particles, in vivo detection of small S. aureus colonies in infection models is feasible by MRI and provides a versatile tool to follow bacterial infections in vivo. The established cell labeling strategy can easily be transferred to other bacterial species and thus provides a conceptual advance in the field of molecular MRI.