Dynamic Tracking of Injected Mesenchymal Stem Cells after Myocardial Infarction in Rats: A Serial 7T MRI Study

Figure 4

MSCs retention in recipient hearts. (a) The number of dual-labeled MSCs decreased over time. At 4 weeks, almost no positive cells were detected (original magnification ×50). (b) Sections stained for iron and CD68 at 4 weeks showed that most of the iron-positive cells (blue cytoplasm) were CD68-positive cardiac macrophages (brown cytoplasm) (original magnification ×200). (c) Representative electron micrographs demonstrated MPIOs engulfment inside a macrophage.

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(b)

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