Figure 5: γδT cells produce IL-17A on bone injury.

(a) IL-17A-producing cells in the drill hole, skeletal muscle and bone marrow. Il17a^gfp/gfp mice were used for the detection of IL-17A-producing cells as EGFP⁺ cells. Nuclei were stained by Hoechst33342. Scale bar, 500 μm. (b) High-magnification images of the drill hole and the injured skeletal muscle 2 and 7 days after injury. Scale bar, 50 μm. (c) Quantification of IL-17A-producing cells within the drill hole and the injured muscle (n=3 per time point, 2 representative sections per each femur). Statistical analysis was carried out using two-way ANOVA with Tukey’s test. (d) The expression of CD3ɛ and TCRγδ in IL-17A-producing cells (EGFP⁺ cells of Il17a^gfp/gfp mice) in the repair tissue (n=3−8 per time point). (e) The number of γδ T cells and the ratio of IL-17A-producing γδ T cells in the repair tissue. Statistical analysis was carried out using one-way ANOVA with Dunnett’s test. (f) Proliferation of γδ T cells after injury. BrdU⁺ γδ T cells were detected by flow cytometry (n=3 per time point). Statistical analysis was carried out using Student’s t-test. Error bars denote the mean±s.e.m. *P<0.05 versus day 0; †P<0.05 at a time point.