Osteoblast CFTR Inactivation Reduces Differentiation and Osteoprotegerin Expression in a Mouse Model of Cystic Fibrosis-Related Bone Disease
Figure 3
CFTR inactivation reduced osteoblast differentiation and bone formation.
(A) The murine calvarial organ culture assay was performed on Cftr+/+ and Cftr−/− mouse pups. After two weeks in culture, new bone formation and osteoblast number was significantly less with Cftr inactivation. Yellow arrows indicate the area of actively mineralizing bone indicated by orange G staining that is distinct from the red staining of eosin. (B) Murine calvarial osteoblasts harvested from Cftr+/+ and Cftr−/− calvariae were grown in culture. Seven days after reaching confluence, osteoblast differentiation was assessed by alkaline phosphatase staining. (C) Proliferation, as assessed by BrdU staining, was modestly increased in Cftr+/+ compared to Cftr−/− calvarial osteoblasts. (D) The proportion of calvarial osteoblasts that were viable, undergoing early apoptosis or late apoptosis was unchanged with CFTR inactivation. (* = p<0.05; ** = p<0.01)