Fig. 4

Tracing MSC homing in nude mice. a Fluorescence assays in vivo. Nude mice of femoral shaft fracture were injected MSC labeled by the GFP (MG) and then randomly divided into two groups, including a Short-Wave treatment group (MG+SW) and a control group (MG) (n = 10/group). MG was examined by an IVIS imaging system 7 days after the operation. b Analysis of total radiant efficiency in the right femur. c Homing of MG to the fracture site, analyzed by histological analysis and immunofluorescence imaging at 28 days after the operation. The rectangular boxes in HE staining sections represent fracture areas, which is the region of interest in immunofluorescence imaging. The MG shown in red accounted for Cy3-labeled antibody. Scale bars 200 μm. d Six high-magnification fields (× 100) were randomly observed, and the number of GFP-positive cells was counted and analyzed. Significantly more MG cells were counted in the femora of animals treated with Short-Wave irradiation. Data represent mean ± SD. Differences were assessed by performing a t test. *P < 0.05. MG injected MSC labeling with the GFP, SW Short-Wave treatment