The ultimate goal is the development of tissue-specific, or directed magnetic resonance imaging (MRI) contrast agents. These agents will consist of peptides attached to small, biodegradable superparamagnetic iron oxide colloids. The biodistribution of the superparamagnetic iron oxide label will be determined by the peptide on the surface of the iron oxide and by the presence of specific receptors in a target tissue. The development of such agents will increase the already considerable diagnostic power of MRI. In Phase I, peptide hormones with receptors in pancreatic tissue will be attached to superparamagnetic iron oxide particles and successful targeting of the pancreas will be demonstrated. The pancreas is our initial target organ because it possesses receptors for a number of low molecular weight peptide hormones (e. g. somatostatin, cholecystokinin, vasoactive intestinal peptide, secretin, and CRP/bombesin). Pancreatic cancer has a high mortality rate due in part to difficulties in assessing the pathology of the pancreas using standard imaging methods, such as CT or MRI.Awardee's statement of the potential commercial applications of the research:This research will lead to the development of a family of new MRI contrast agents targeted to specific organs/tissues. While the initial target organ is the pancreas, the approach developed here can be used in conjunction with many receptors, allowing imaging of a wide variety of organs and tumoral tissues. Receptor directed MRI contrast agents will greatly extend the utility of MR imaging in clinical practice.National Cancer Institute (NCI)
