Bone Marrow-Derived CD44⁺ Cells Migrate to Tissue-Engineered Constructs via SDF-1/CXCR4-JNK Pathway and Aid Bone Repair

Figure 4

The SDF-1/CXCR4 axis promoted the migration of GFP⁺/CD44⁺ bone marrow (BM) cells. (a) Representative images of migrated BM cells in different groups. The quantification of the migrated BM cells is shown as a bar graph (). . . (b) Comparison of CXCR4 protein expression after SDF-1 induction. After migration stopped, BM cells were collected and analyzed by western blot. (c) Postoperatively, the concentration of SDF-1 in different tissues was measured daily using ELISA. The different tendency is presented on the line chart. (d) FACS analysis of the proportions of CD44⁺ cells in PB. Postoperatively, cells collected from peripheral blood (PB) of mice receiving AMD3100 or not were incubated with fluorescently conjugated antibodies against CD44 and analyzed using the CytoFLEX software. The quantification comparison is shown as a bar graph (). . (e) Representative images of in vivo migration of GFP⁺/CD44⁺ cells towards TECs. The recruitment of GFP⁺/CD44⁺ cells was significantly reduced after systematic delivery of the AMD3100 group. White triangle, implant area; white arrows, GFP⁺/CD44⁺ cells; scale bar, 50 mm. TECs, tissue-engineered constructs. MSC-CM, conditioned media of mesenchymal stem cells. BCM, basic culture medium.

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