1Department
of Medical Biophysics, Robarts Research Institute, London, Ontario, Canada; 2Department
of Chemistry, Western University, London, Ontario, Canada; 3Imaging
Research Laboratories, Robarts Research Institute, London, On, Canada; 4Imaging
Research Laboratories, Robarts Research Institute, London, Ontario, Canada; 5Department
of Chemistry, Western University, London, On, Canada; 6Department
of Clinical Neurological Sciences, Robarts Research Institute, London,
Ontario, Canada; 7Department of Physiology and Pharmacology,
Schulich School of Medicine, Western University, London, Ontario, Canada; 8Imaging
Research Laboratories, Robarts Research Institute, London, Onta, Canada
Programmed cell death (apoptosis) is an important feature for studies of cancer therapy as well as ischemia and neurological pathologies. Recently, we have synthesized a novel MRI and fluorescent contrast agent containing a cleavage site specific to Caspase 3. Prostate cancer cells were either irradiated with ultraviolet radiation or maintained without insult. 24 hour incubation with our contrast agent permitted differentiation of irradiated versus control cells with both confocal microscopy and PARACEST MRI. This work provides a proof-of-principle of PARACEST imaging for the detection of apoptotic cell population following ionizing radiation.