The culture and the dual-labeling of MSCs. A) At passage 2, MSCs appeared uniformly spindle-shaped (×100). B) Cells became compact and uniformly aligned in bundles at day 14 (×100). C) Prussian blue-stained cells contained cytoplasmic blue particles and SPIO-labeling efficiency was almost 100% (×100). D) DiD-labeled cells appear red under fluorescence microscopy (×100; excitation wavelength 595–800 nm, emission 660–680 nm). E) Cell proliferation viability was measured by MTT assay for dual-labeled and unlabeled cells
Note: *P > 0.05.
Abbreviations: MSCs, mesenchymal stem cells; SPIO, superparamagnetic iron oxide nanoparticle; DiD, 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindodicarbocyanine, 4-chlorobenzenesulfonate salt; MTT, methyl thiazolyl tetrazolium.