Single-cell detection by gradient echo 9.4 T MRI: a parametric study.
Recent studies have shown that cell migration can be monitored in vivo by magnetic resonance imaging after intracellular contrast agent incorporation. This is due to the dephasing effect on proton magnetization of the local magnetic field created by a labelled cell. Anionic iron oxide nanoparticles (AMNP) are among the most efficient and non-toxic contrast agents to be spontaneously taken up by a wide variety of cells. Here we measured the iron load and magnetization of HeLa tumour cells labelled with AMNP, as a function of the external magnetic field. High-resolution gradient echo 9.4 T MRI detected individual labelled cells, whereas spin echo sequences were poorly sensitive. We then conducted a systematic study in order to determine the gradient echo sequence parameters (echo time, cell magnetization and resolution) most suitable for in vivo identification of single cells.
Smirnov
P
P
Laboratoire Matière et Systèmes Complexes, Université Paris 7, Denis Diderot and CNRS UMR 7057, 140, rue de Lourmel, 75015 Paris, France. pierre_smirnov@hotmail.com
Gazeau
F
F
Beloeil
J-C
JC
Doan
B T
BT
Wilhelm
C
C
Gillet
B
B
D002470:Cell Survival; D002477:Cells / Q000166:cytology* / Q000378:metabolism*; D005290:Ferric Compounds / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D007501:Iron / Q000378:metabolism; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008280:Magnetics; D013997:Time Factors
D005290:Ferric Compounds; C000499:ferric oxide; D007501:Iron