Patrick Winter1, John Pearce1, Zhengtao Chu2, Jing-Huei Lee3, Xiaoyang Qi2
1Radiology, Cincinnati Children's Hospital, Cincinnati, OH, United States; 2Hematology and Oncology, University of Cincinnati, Cincinnati, OH, United States; 3Center for Imaging Research, University of Cincinnati, Cincinnati, OH, United States
Saposin C (SapC) preferentially binds to phosphatidylserine, which is expressed on tumor cells, but not normal tissues. A novel targeted MRI contrast agent was produced by incorporating paramagnetic gadolinium chelates onto SapC vesicles. The targeting ability of paramagnetic SapC vesicles was studied in vitro with cultured cancer cells and in vivo with a tumor bearing mouse model. These experiments demonstrate that paramagnetic SapC vesicles can target tumors in vivo, providing noninvasive mapping of the cancer biomarker phosphatidylserine.