Mohammed Salman Shazeeb1,2, Christopher
Howard Sotak, 1,3, Alexei Bogdanov3
1Department of Biomedical Engineering,
Worcester Polytechnic Institute, Worcester, MA, United States; 2Graduate
School of Biomedical Sciences, University of Massachusetts Medical School, Worcester,
MA, United States; 3Department of Radiology, University of
Massachusetts Medical School, Worcester, MA, United States
Targeted
EGF receptor imaging in Gli36 tumor xenografts implanted in the rat brain was
achieved using monoclonal antibody (mAb) conjugates that facilitate local
binding of a paramagnetic molecular substrate diTyr-DTPA(Gd) at the EGFR
expression sites. Following mAb
conjugate administration, diTyr-DTPA(Gd) was retained for a significantly longer
period of time as compared to the administration of the contrast agent
without mAb conjugate pre-treatment.
The increased retention of diTyr-DTPA(Gd) following mAb conjugate
administration is consistent with enzyme-mediated coupling of the paramagnetic
agent to EGFR-overexpressing cells in the tumor; allowing effective MRI
visualization of conjugate co-localization at the targeted site.