Greetje Vande Velde1, Janaki Raman Rangarajan2, Tom Dresselaers3, Olga Krylyshkina1, Abdelilah Ibrahimi1, Zeger Debyser1, Veerle Baekelandt1, Uwe Himmelreich3
1Molecular Medicine, Katholieke Universiteit Leuven, Leuven, Flanders, Belgium; 2Medical Imaging Center, Katholieke Universiteit Leuven, Leuven, Flanders, Belgium; 3Biomedical Nuclear NMR unit, Katholieke Universiteit Leuven, Leuven, Flanders, Belgium
Utilizing lentiviral (LV) and adeno-associated (AAV) viral vector systems for delivering MRI reporter genes (e.g. ferritin) will allow stable labeling and in vivo visualization of marked cells, but their potential limitations for MRI are often insufficiently addressed. Injection in rodent brain of LV/AAV without MRI reporter genes results in hypointense contrast at the injection site on T2*-weighted MRI that correlates with the presence of Fe3+ and microglia. This challenges the signal-to-noise properties of putative MRI reporter genes.