Fig. 5
Defects in growth plate, organisation of columnar chondrocytes, secondary ossification, articulation and cavitation of joints and proteoglycan turnover in Lrp1flox/flox/Prrx1Cre mice. Representative images of H&E and safranin-O/fast green staining in shoulder (a), elbow (b), knee (c) and hip (d) joint sections of 2- and/or 14-week-old WT and Lrp1flox/flox/Prrx1Cre (cKO) mice. Arrow indicates the extra groove of femoral heads (d). Regions delineated by the dark blue squares in the panels have been magnified in the right panels. Scale bar, 200 µm. GP, growth plate; AC, articular cartilage; F, femur; T, tibia; M, menisci. e, Representative images of immunohistochemical staining of SOX9 in knee articular cartilage and growth plate sections of 14-week-old WT and cKO mice. Arrow heads indicate cells with SOX9 positive staining. Scale bar, 50 µm. f Representative images of fluorescent microscopy analysis of calcein-double stained cortical bones in 14-week-old mice (n = 3 each). Red arrowheads indicate calcein double staining in cortical bone. Scale bar, 50 µm. g TRAP and aniline blue staining of tibia trabecular bone of 14-week-old mice. Yellow arrowheads highlight osteoclast staining. Scale bar, 50 µm. TB, trabecular bone; GP, growth plate. h Measurement of osteoclast numbers in WT and Lrp1flox/flox/Prrx1Cre (cKO) trabecular bones. Circles represent individual mice and bars show the mean ± SD. ***P < 0.001 by 2-tailed Student’s t test
