Guanshu Liu1,2,
Chetan Bettegowda3, Assaf A. Gilad4,5, Michael T.
McMahon1,2, Kannie W. Y. Chan2,5, Kenneth W. Kinzler3,
Bert Vogelstein3, Jeff W. M. Bulte2,5, Shibin Zhou3,
Peter C. M. van Zijl1,2
1F. M. Kirby
center, Kennedy Krieger Institute, Baltimore, MD, USA; 2Department
of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD,
USA; 3Ludwig Center, Howard Hughes Medical Institute & Sidney
Kimmel Cancer Center, Johns Hopkins University School of Medicine, Baltimore,
MD, USA; 4Department of Radiology, Johns Hopkins University School
of Medicine, Baltimore, MD, USA; 5Institute for Cell Engineering,
Johns Hopkins University School of Medicine, Baltimore, MD, USA
Bacteriolytic therapy has recently emerged as a promising approach for cancer therapy, in which anaerobic bacteria are utilized to selectively destroy the hypoxic cores of solid tumors. To facilitate its clinical translation, we sought to develop a non-invasive MR imaging method that is capable of monitoring infection with Clostridium novyi-NT. An inherent Chemical Exchange Saturation Transfer (CEST) signal at 2.6 ppm from the water proton signal was found in cultures of this bacterium in vitro. Using this signal, we were able to detect the germination of the anaerobic bacteria in vivo.