Comparison of optical bioluminescence reporter gene and superparamagnetic iron oxide MR contrast agent as cell markers for noninvasive imaging of cardiac cell transplantation.
OBJECTIVE
In this study, we compared firefly luciferase (Fluc) reporter gene and superparamagnetic iron oxide (Feridex) as cell markers for longitudinal monitoring of cardiomyoblast graft survival using optical bioluminescence imaging (BLI) and magnetic resonance imaging (MRI), respectively.


METHODS
Rats (n = 31) underwent an intramyocardial injection of cardiomyoblasts (2 x 10(6)) labeled with Fluc, Feridex, or no marker (control) or an injection of Feridex alone (75 microg). Afterward, rats were serially imaged with BLI or MRI and killed at different time points for histological analysis.


RESULTS
BLI revealed a drastically different cell survival kinetics (half-life = 2.65 days over 6 days) than that revealed by MRI (half-life = 16.8 days over 80 days). Injection of Feridex alone led to prolonged tissue retention of Feridex (> or =16 days) and persistent MR signal (> or =42 days).


CONCLUSIONS
Fluc BLI reporter gene imaging is a more accurate gauge of transplanted cell survival as compared to MRI of Feridex-labeled cells.
Chen
Ian Y
IY
Molecular Imaging Program at Stanford, Stanford University School of Medicine, Stanford, CA, USA.
Greve
Joan M
JM
Gheysens
Olivier
O
Willmann
Jürgen K
JK
Rodriguez-Porcel
Martin
M
Chu
Pauline
P
Sheikh
Ahmad Y
AY
Faranesh
Anthony Z
AZ
Paulmurugan
Ramasamy
R
Yang
Phillip C
PC
Wu
Joseph C
JC
Gambhir
Sanjiv S
SS
D000818:Animals; D017690:Cell Transplantation / Q000379:methods*; D003287:Contrast Media; D003584:Cytological Techniques; D003911:Dextrans; D003952:Diagnostic Imaging / Q000379:methods*; D005290:Ferric Compounds; D052203:Ferrosoferric Oxide; D017930:Genes, Reporter; D007501:Iron; D049409:Luciferases, Firefly; D008163:Luminescent Measurements / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles; D032383:Myocytes, Cardiac / Q000637:transplantation*; D010087:Oxides; D051381:Rats
D003287:Contrast Media; D003911:Dextrans; D005290:Ferric Compounds; D058185:Magnetite Nanoparticles; D010087:Oxides; C000499:ferric oxide; D007501:Iron; D049409:Luciferases, Firefly; C065507:ferumoxides; D052203:Ferrosoferric Oxide