FIG. 6.

Labeling and tracking of the MSCs. (A) MSC cell membranes were labeled using the PKH67 kit (green fluorescence), and the labeling efficiency was evaluated using fluorescence microscopy (Scale bar, 10 μm). (B) Labeled MSCs were cultured in expansion medium for 2 days, and maintained labeling was verified using fluorescence microscopy (Scale bar, 50 μm). (C) The presence of labeled MSCs was determined in the nucleus pulposus region after 14 days in organ culture (scale bar, 50 μm). (D) Magnification of (C) (scale bar, 10 μm).