Macroscopic fluorescence imaging of tumor-bearing mice.

<p>(A-E) Movement of strong fluorescent signals was observed in subcutaneous xenograft models at 1, 3, 5, 7, and 10 days after the intravenous injection of TRAIL-MSCs (n = 3). The arrows show the tumor locations. (F) No significant fluorescence signals were observed around tumor sites in the mice injected with MSCs (n = 3) as the control group.