Specific Imaging of Bacterial Infection Using 6″-18F-Fluoromaltotriose: A Second-Generation PET Tracer Targeting the Maltodextrin Transporter in Bacteria

J Nucl Med. 2017 Oct;58(10):1679-1684. doi: 10.2967/jnumed.117.191452. Epub 2017 May 10.

Abstract

6″-18F-fluoromaltotriose is a PET tracer that can potentially be used to image and localize most bacterial infections, much like 18F-FDG has been used to image and localize most cancers. However, unlike 18F-FDG, 6″-18F-fluoromaltotriose is not taken up by inflammatory lesions and appears to be specific to bacterial infections by targeting the maltodextrin transporter that is expressed in gram-positive and gram-negative strains of bacteria. Methods: 6″-18F-fluoromaltotriose was synthesized with high radiochemical purity and evaluated in several clinically relevant bacterial strains in cultures and in living mice. Results: 6″-18F-fluoromaltotriose was taken up in both gram-positive and gram-negative bacterial strains. 6″-18F-fluoromaltotriose was also able to detect Pseudomonas aeruginosa in a clinically relevant mouse model of wound infection. The utility of 6″-18F-fluoromaltotriose to help monitor antibiotic therapies was also evaluated in rats. Conclusion: 6″-18F-fluoromaltotriose is a promising new tracer that has significant diagnostic utility, with the potential to change the clinical management of patients with infectious diseases of bacterial origin.

Keywords: 6″-18F-fluoromaltotriose; PET/CT imaging; bacteria; infection imaging.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Bacterial Infections / diagnostic imaging*
  • Bacterial Infections / metabolism*
  • Biological Transport
  • Membrane Transport Proteins / metabolism*
  • Mice
  • Mice, Nude
  • Polysaccharides / metabolism*
  • Positron-Emission Tomography / methods*
  • Radioactive Tracers
  • Trisaccharides*
  • Wound Infection / diagnostic imaging
  • Wound Infection / metabolism

Substances

  • 6''-fluoromaltotriose
  • Membrane Transport Proteins
  • Polysaccharides
  • Radioactive Tracers
  • Trisaccharides
  • maltotriose
  • maltodextrin