Osteopenia in Cftr-deltaF508 mice

Abstract 

Background

Mice with the cystic fibrosis transmembrane conductance regulator (Cftr) gene knocked out develop osteopenia. To determine whether this phenotype is present in cystic fibrosis mouse models with the ΔF508 Cftr mutation we assessed the femora of adult FVB/N Cftr^tm1Eur and C57BL/6 Cftr^tm1Kth mice.

Methods

Bone disease, relative to littermate controls, was measured using histology, densitometry and quantitative imaging.

Results

C57BL/6 Cftr^tm1Kth mice had shorter femurs and bones of lower volume due to thinner trabeculae, compared to wild type littermates. FVB/N Cftr^tm1Eur mice also presented a lower bone volume which was due to significantly fewer trabeculae in this strain. Osteoblast and osteoclast numbers did not differ between CF and controls, for either of FVB/N Cftr^tm1Eur or C57BL/6 Cftr^tm1Kth mice. The bone architecture of FVB/N Cftr^tm1Eur mice did not significantly differ from that of C57BL/6 Cftr^tm1Kth mice.

Conclusions

An osteopenic bone disease is evident in adult ΔF508-Cftr cystic fibrosis mouse models.

Keywords: Bone disease, Genetically modified mouse, Cftr, deltaF508, Femur