Local treatment of cricoid cartilage defects with rhBMP-2 induces growth plate-like morphology of chondrogenesis.
OBJECTIVE
The ultrastructural characteristics of new bone and cartilage, induced at the site of cricoid cartilage defects treated with rhBMP-2 in rabbits, were investigated.


METHODS
A cricoid defect model was used. Fifteen rabbits were randomly and equally divided into 3 groups. Four rabbits from each group were treated with rhBMP-2, while one rabbit from each group was used as control. The rabbits were killed 1, 2, or 4 weeks after surgery. The healing pattern of the laryngeal wound was evaluated by light and transmission electron microscopy.


RESULTS
Mineralized collagen type I matrix, osteoblasts, and osteoclast-like cells were present as early as 1 week after surgery. Well-structured bone trabeculas and growth plate-like structures were present 4 weeks after surgery.


CONCLUSIONS
Intramembranous and endochondral osteogenesis take place at the site of cricoid cartilage defects treated with rhBMP-2. Progenitor cells of cricoid perichondrium form a growth plate-like structure similar to the epiphyseal growth plate.


CONCLUSIONS
This study reveals the pattern of BMP-2-induced repair of airway cartilage defects.
Tcacencu
Ion
I
Department of Otorhinolaryngology, Karolinska University Hospital-Huddinge, Karolinska Institutet, SE-14186 Stockholm, Sweden. tcacencu@yahoo.co.uk
Carlsöö
Bengt
B
Stierna
Pontus
P
Hultenby
Kjell
K
D000818:Animals; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000627:therapeutic use*; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D019902:Chondrocytes / Q000187:drug effects / Q000473:pathology; D020219:Chondrogenesis / Q000187:drug effects*; D024042:Collagen Type I / Q000187:drug effects / Q000648:ultrastructure; D003413:Cricoid Cartilage / Q000187:drug effects* / Q000473:pathology; D004195:Disease Models, Animal; D006132:Growth Plate / Q000187:drug effects* / Q000473:pathology; D007818:Laryngeal Diseases / Q000188:drug therapy* / Q000473:pathology; D008297:Male; D046529:Microscopy, Electron, Transmission; D010006:Osteoblasts / Q000187:drug effects / Q000473:pathology; D010010:Osteoclasts / Q000187:drug effects / Q000473:pathology; D010012:Osteogenesis / Q000187:drug effects; D011817:Rabbits; D011897:Random Allocation; D011994:Recombinant Proteins / Q000627:therapeutic use*; D013997:Time Factors; D016212:Transforming Growth Factor beta / Q000627:therapeutic use*; D014945:Wound Healing / Q000187:drug effects
D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D024042:Collagen Type I; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2