In this report, we generated a ferritin and red ?uorescent protein fusion reporter gene that enables the visuali-zation of transgene expression in living animals by magnetic resonance imaging (MRI) and optical imaging. Ferritin heavy chain (FTH) or light chain (FTL) was linked to the N terminus of the monomeric DsRed red ?uorescent protein to create FTH-DsRed and FTL-DsRed, MRI-?uorescence dual reporters. Transfection of these dual reporters into cells resulted in increased iron loading and strong red ?uorescence in cells. Adenoviral vectors to express FTH-DsRed or FTL-DsRed fusion reporter in infected cells were created, but only the adenovirus expressing FTH-DsRed resulted in a high level of red ?uorescence in cells. Delivery and expression of FTH-DsRed in the mouse brain using adenovirus was detected by MRI and ?uorescence imaging, revealing a T 2 shortening e?ect and an increase of contrast in T 2 -weighted images at the sites co-localized with strong red ?uorescence. While the details of the structure of ferritin-DsRed fusion reporter remains to be solved, this dual reporter is useful for visualizing dynamic processes such as the migration of reporter-transfected stem cells or metastasis of tumors using MRI with the added ?exibility of combining optical tools such as ?uorescence activated cell sorting and ?uorescence microscopy.
Date:
2012-08
Relation:
Biomedical Engineering: Applications, Basis and Communications. 2012 Aug;24(4):333-341.
