Monitoring of implanted stem cell migration in vivo: a highly resolved in vivo magnetic resonance imaging investigation of experimental stroke in rat.
In vivo monitoring of stem cells after grafting is essential for a better understanding of their migrational dynamics and differentiation processes and of their regeneration potential. Migration of endogenous or grafted stem cells and neurons has been described in vertebrate brain, both under normal conditions from the subventricular zone along the rostral migratory stream and under pathophysiological conditions, such as degeneration or focal cerebral ischemia. Those studies, however, relied on invasive analysis of brain sections in combination with appropriate staining techniques. Here, we demonstrate the observation of cell migration under in vivo conditions, allowing the monitoring of the cell dynamics within individual animals, and for a prolonged time. Embryonic stem (ES) cells, constitutively expressing the GFP, were labeled by a lipofection procedure with a MRI contrast agent and implanted into rat brains. Focal cerebral ischemia had been induced 2 weeks before implantation of ES cells into the healthy, contralateral hemisphere. MRI at 78-microm isotropic spatial resolution permitted the observation of the implanted cells with high contrast against the host tissue, and was confirmed by GFP registration. During 3 weeks, cells migrated along the corpus callosum to the ventricular walls, and massively populated the borderzone of the damaged brain tissue on the hemisphere opposite to the implantation sites. Our results indicate that ES cells have high migrational dynamics, targeted to the cerebral lesion area. The imaging approach is ideally suited for the noninvasive observation of cell migration, engraftment, and morphological differentiation at high spatial and temporal resolution.
Hoehn
Mathias
M
Max Planck Institute for Neurological Research, Gleuelerstrasse 50, D-50931 Cologne, Germany Europe. mathias@mpin-loeln.mpg.de
Küstermann
Ekkehard
E
Blunk
James
J
Wiedermann
Dirk
D
Trapp
Thorsten
T
Wecker
Stefan
S
Föcking
Melanie
M
Arnold
Heinz
H
Hescheler
Jürgen
J
Fleischmann
Bernd K
BK
Schwindt
Wolfram
W
Bührle
Christian
C
D000818:Animals; D002465:Cell Movement; D002478:Cells, Cultured / Q000637:transplantation; D002540:Cerebral Cortex; D003287:Contrast Media; D003337:Corpus Callosum; D004578:Electron Spin Resonance Spectroscopy; D016332:Fetal Tissue Transplantation; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins; D006624:Hippocampus / Q000166:cytology; D021621:Imaging, Three-Dimensional; D020244:Infarction, Middle Cerebral Artery / Q000473:pathology / Q000628:therapy*; D008164:Luminescent Proteins / Q000032:analysis / Q000235:genetics; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D023421:Models, Animal; D009474:Neurons / Q000637:transplantation; D051381:Rats; D017208:Rats, Wistar; D012680:Sensitivity and Specificity; D033581:Stem Cell Transplantation; D014183:Transplantation, Heterologous
D003287:Contrast Media; D008164:Luminescent Proteins; D049452:Green Fluorescent Proteins