Objective: To show the phenotypic characteristics of the knee joints in brachypodism mice (bp mice), which carry a functional null mutation of the growth differentiation factor 5 (GDF5) gene, we investigated the adult and embryonic bp mice. Method: Radiographic and macroscopic examinations of the knee joint of adult bp mice were performed. A histological examination of the knee joint of bp mice from E12.5 to E18.5 was also performed. Results: Radiographic and macroscopic examinations of the adult bp mice showed anterior dislocation, hypoplastic condyles, and absence of the intra-articular ligaments. Safranin O staining of knee joints of the embryonic bp mice showed severe hypoplasty of the chondroepiphyses and intra-articular ligaments at E16.5. There was no difference in the number and location of 5-bromo-2′-deoxyuridine (BrdU)-positive cells between wild-type and bp mice through E12.5 to E14.5. A terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling (TUNEL) study showed excessive cell death of mesenchymal cells of the future knee joint in bp mice at E12.5 and E13.5. Conclusion: bp mice exhibit developmental failure of the condyles and intra-articular ligament of the knee joints. © 2006 Osteoarthritis Research Society International.
Harada, M., Takahara, M., Zhe, P., Otsuji, M., Iuchi, Y., Takagi, M., & Ogino, T. (2007). Developmental failure of the intra-articular ligaments in mice with absence of growth differentiation factor 5. Osteoarthritis and Cartilage, 15(4), 468–474. https://doi.org/10.1016/j.joca.2006.09.003