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New pathogen-specific immunoPET/MR tracer for molecular imaging of a systemic bacterial infection.

ABSTRACT: The specific and rapid detection of Enterobacteriaceae, the most frequent cause of gram-negative bacterial infections in humans, remains a major challenge. We developed a non-invasive method to rapidly detect systemic Yersinia enterocolitica infections using immunoPET (antibody-targeted positron emission tomography) with [64Cu]NODAGA-labeled Yersinia-specific polyclonal antibodies targeting the outer membrane protein YadA. In contrast to the tracer [18F]FDG, [64Cu]NODAGA-YadA uptake co-localized in a dose dependent manner with bacterial lesions of Yersinia-infected mice, as detected by magnetic resonance (MR) imaging. This was accompanied by elevated uptake of [64Cu]NODAGA-YadA in infected tissues, in ex vivo biodistribution studies, whereas reduced uptake was observed following blocking with unlabeled anti-YadA antibody. We show, for the first time, a bacteria-specific, antibody-based, in vivo imaging method for the diagnosis of a Gram-negative enterobacterial infection as a proof of concept, which may provide new insights into pathogen-host interactions.

SUBMITTER: Wiehr S

PROVIDER: S-EPMC4905453 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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New pathogen-specific immunoPET/MR tracer for molecular imaging of a systemic bacterial infection.

Wiehr Stefan S Warnke Philipp P Rolle Anna-Maria AM Schütz Monika M Oberhettinger Philipp P Kohlhofer Ursula U Quintanilla-Martinez Leticia L Maurer Andreas A Thornton Christopher C Boschetti Frederic F Reischl Gerald G Autenrieth Ingo B IB Pichler Bernd J BJ Autenrieth Stella E SE

Oncotarget 20160301 10

The specific and rapid detection of Enterobacteriaceae, the most frequent cause of gram-negative bacterial infections in humans, remains a major challenge. We developed a non-invasive method to rapidly detect systemic Yersinia enterocolitica infections using immunoPET (antibody-targeted positron emission tomography) with [64Cu]NODAGA-labeled Yersinia-specific polyclonal antibodies targeting the outer membrane protein YadA. In contrast to the tracer [18F]FDG, [64Cu]NODAGA-YadA uptake co-localized ...[more]

PMID: 26934329

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Dataset Information

New pathogen-specific immunoPET/MR tracer for molecular imaging of a systemic bacterial infection.

Publications

New pathogen-specific immunoPET/MR tracer for molecular imaging of a systemic bacterial infection.

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