Fig. 3: Increased extension of the osteoblast front in the long bone of Clec14a^−/− mice.

A Representative images of Osx (cyan) immunolabeled metaphyseal and diaphyseal bone sections from P4 neonatal pups. Dashed line demarcates the bone edge of images and the most distal point of the proximal growth plate. Note the extension of Osx⁺ cells in Clec14a^−/−. Scale bars are 100 µm. B Quantitative measurements of osteoblast density per µm² in the P4 mouse tibia metaphysis and diaphysis. C Quantification of the length of osteoblast chords in the neonatal (P4) murine tibia. An osteoblast chord was defined as an aggregation of Osx⁺ cells organised in a column. The length of osteoblast chords from the proximal end of the metaphysis to their most distal point was measured. Individual dots represent the mean length of osteoblast chords in one biological replicate. Data was analysed with a Mann–Whitney test, results are presented as median ± IQR *P < 0.05, ns = not significant. D Representative maximum intensity projections of Col1a1 immunolabeled bone sections in 4-week-old mice. Upper image: white dashed line delineates the boundary between the growth plate (avascular) and the metaphysis. Lower image: dashed line demarcates the area covered by bone including the bone endosteum and periosteum. Scale bars are 100 µm. E Quantification of the percentage (%) area covered by Col1a1 immunolabeling in the tibial metaphysis (left) and diaphysis (right). F Quantification of the length of type I collagen chords in the juvenile murine tibia. Data analysed with a Mann–Whitney test, results are presented as median ± IQR, **P < 0.01, ns = not significant.