title: A correlative immuno-light and electron microscopic study on the type I collagen in the bone morphogenetic protein-induced cartilage.
abstract: Bone morphogenetic protein (BMP) partially purified from bovine bone was implanted into the thigh muscles of AKR-strain mice to induce an ectopic endochondral ossification tissue. The extracellular matrix components around the hypertrophic chondrocytes in the induced tissue were examined by electron microscopy and immunohistochemistry for type I collagen. At 14 days after implantation, chondrocytes became hypertrophic with calcifying matrix around them. Some hypertrophic chondrocytes showed no degenerative appearances. They were ringed by a pericellular matrix with no metachromasia which was distinct from the metachromatic cartilage matrix. The localization of type I collagen was demonstrated by immuno-staining in this matrix. Ultrastructurally, ring-shaped matrix consisted of interwoven collagen fibrils on which a D-periodic banding pattern could be discerned. Immunoelectron microscopy demonstrated immunoreactivity of type I collagen on these fibrils. These results suggest that some of the BMP-induced hypertrophic chondrocytes maintain their activity and produce type I collagen-rich matrix before their lacunae are eroded.
authors.affiliation: Department of Oral Surgery, Nagoya University School of Medicine, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Hattori
authors.forename: M
authors.initials: M
authors.lastname: Kawai
authors.forename: K
authors.initials: K
authors.lastname: Yasue
authors.forename: H
authors.initials: H
authors.lastname: Mizutani
authors.forename: M
authors.initials: M
authors.lastname: Kobayashi
authors.forename: T
authors.initials: T
authors.lastname: Kaneda
authors.forename: T
authors.initials: T
authors.lastname: Hoshino
mesh_terms: D000818:Animals; D019485:Bone Morphogenetic Proteins; D002356:Cartilage / Q000737:chemistry* / Q000187:drug effects / Q000648:ultrastructure; D003094:Collagen / Q000032:analysis*; D005109:Extracellular Matrix / Q000737:chemistry / Q000648:ultrastructure; D008297:Male; D051379:Mice; D008806:Mice, Inbred AKR; D016253:Microscopy, Immunoelectron; D009999:Ossification, Heterotopic / Q000139:chemically induced*; D011506:Proteins / Q000494:pharmacology*
chemical_list: D019485:Bone Morphogenetic Proteins; D011506:Proteins; D003094:Collagen