Fig. 5. IL-37 accelerated bone healing in a rat calvarial bone defects model.

a 3D construction images of μCT analyses and quantitive μCT analyses of BV/TV and Tb.Th, scale bar = 1 mm; b, c Histological analyses, including H&E, SO/FG, and Masson’s trichrome staining, showed that the calvarial defects in the Blank and BMSC groups were filled with fibrous tissue and a few bridging bone formation. In the IL-37 group, a thick callus consisting of newly formed bone tissue was observed in the defect area. In the BMSC+IL-37 group, large and thick callus was observed in the defect area and the remaining defect size was significantly smaller than other groups, indicating more complete bone healing of the defect, scale bars = 500 μm. Yellow arrowheads: the newly formed bone tissue. *P < 0.05 vs. Blank group; ^#P < 0.05 vs. BMSCs group