Neurotransplantation of magnetically labeled oligodendrocyte progenitors: Magnetic resonance tracking of cell migration and myelination

Demyelination is a common pathological finding in human neurological diseas es and frequently persists as a result of failure of endogenous repair. Tra nsplanted oligodendrocytes and their precursor cells can (re)myelinate axon s, raising the possibility of therapeutic intervention. The migratory capac ity of transplanted cells is of key importance in determining the extent of (re)myelination and can, at present, be evaluated only by using invasive a nd irreversible procedures. We have exploited the transferrin receptor as a n efficient intracellular delivery device for magnetic nanoparticles, and t ransplanted tagged oligodendrocyte progenitor cells into the spinal cord of myelin-deficient rats. Cell migration could be easily detected by using th ree-dimensional magnetic resonance microscopy, with a close correlation bet ween the areas of contrast enhancement and the achieved extent of myelinati on. The present results demonstrate that magnetic resonance tracking of tra nsplanted oligodendrocyte progenitors is feasible; this technique has the p otential to be easily extended to other neurotransplantation studies involv ing different precursor cell types.