Figure 3: MRI of magA cell induction in vivo. (a) T2*-weighted image of a mouse brain with transplanted magA cells (right, white arrow) and GFP control cells (left). These cells were not induced or incubated with iron supplement prior to transplantation. MagA cells exhibited significantly lower MR signals, reflecting an increase in R2 and suggesting that magA cells are able to use endogenous iron sources. The control cells on the left do not show this effect. (b) MR image of the same mouse brain showing that magA cells are readily seen by T2WI, which is less sensitive than T2* for magnetic nanoparticles. Fluorescence histology confirmed the presence of control (green) and magA-positive (red) cells. Magnified green and red channels are also shown. (c) Brightfield histology section of the brain, indicating the site of the transplanted cells.