Fig. 3: Angiogenesis and osteogenesis within FP-TEBs are dependent on CXCR2 activation of ECs.

a Schematic diagram of the experiments for assessing the angiogenic and osteogenic effects. b Representative immunostaining images with quantification of cell numbers in critical-size bone defects at 2 weeks postoperatively (n = 5). White arrows, staining-positive cells. Scale bar, 10 μm. c Representative Micro-fill perfusion images of bone defect areas from cxcr2^flox and cxcr2^tek treated with FP-TEBs at 2 weeks postoperatively. d H&E and Masson staining at 4 week postoperatively. Dotted straight black line indicates the femur-implant junction (I, implant area). Scale bars, 500 μm. e Micro-CT reconstruction and quantitative analysis of the bone volume (BV), Tb. Sp (Trabecular separation), and Tb. Th (Trabecular thickness) of bone defect areas from the cxcr2^flox and cxcr2^tek mice at 4 weeks postoperatively (n = 5). Dotted straight red line indicates the area of interest for quantitative analysis. Data are presented as the mean ± SEM. **P < 0.01.