Figure 4

LepR⁺Runx2-GFP^low cells differentiate into osteoblasts through multilayered cell formation in response to PTH-induced anabolic effects. (A–F) Z-stack confocal images of thick bone sections of 6 week-old LepR-Cre/Tomato/Runx2-GFP mice (A and B), tamoxifen-administered iOsx/Tomato/Runx2-GFP mice (C and D), and tamoxifen-administered iOsx/Tomato/Col1(2.3)-GFP mice (E and F) with vehicle (A,C and E) and hPTH(1–34) (B,D and F) intermittent treatment. Arrows: LepR-Cre-derived Tomato⁺(LepR/Tomato⁺)Runx2-GFP⁺ cells (A and B), iOsx/Tomato⁺Runx2-GFP⁺ cells (D) and iOsx/Tomato⁺Col1(2.3)-GFP⁺ cells (F). Arrowheads: iOsx/Tomato⁻Runx2-GFP⁺ cells (C and D) and iOsx/Tomato⁺Col1(2.3)-GFP⁻ cells (F). *: Bone-lining mature osteoblasts. Nuclei were visualized with To-PRO-3 (blue).