title: Repair of osteochondral defects in a rabbit model using a porous hydroxyapatite collagen composite impregnated with bone morphogenetic protein-2.
abstract: Articular cartilage has a limited capacity for spontaneous repair, and an effective method to repair damaged articular cartilage has not yet been established. The purpose of this study was to evaluate the effect of transplantation of porous hydroxyapatite collagen (HAp/Col) impregnated with bone morphogenetic protein-2 (BMP-2). To evaluate the characteristics of porous HAp/Col as a drug delivery carrier of recombinant human BMP-2 (rhBMP-2), the rhBMP-2 adsorption capacity and release kinetics of porous HAp/Col were analyzed. Porous HAp/Col impregnated with different amounts of rhBMP-2 (0, 5, and 25 μg) was implanted into osteochondral defects generated in the patellar groove of Japanese white rabbits to evaluate the effect on osteochondral defect regeneration. At 3, 6, 12, and 24 weeks after operation, samples were harvested and subjected to micro-computed tomography analysis and histological evaluation of articular cartilage and subchondral bone repair. The adsorption capacity was 329.4 μg of rhBMP-2 per cm(3) of porous HAp/Col. Although 36% of rhBMP-2 was released within 24 h, more than 50% of the rhBMP-2 was retained in the porous HAp/Col through the course of the experiment. Defects treated with 5 μg of rhBMP-2 showed the most extensive subchondral bone repair and the highest histological regeneration score, and differences against the untreated defect group were significant. The histological regeneration score of defects treated with 25 μg of rhBMP-2 increased up to 6 weeks after implantation, but then decreased. Porous HAp/Col, therefore, is an appropriate carrier for rhBMP-2. Implantation of porous HAp/Col impregnated with rhBMP-2 is effective for rigid subchondral bone repair, which is important for the repair of the smooth articular surface.
authors: Department of Orthopaedic and Spinal Surgery, Tokyo Medical and Dental University, Tokyo, Japan.
authors: Takashi
authors: T
authors: Taniyama
authors: Department of Orthopaedic and Spinal Surgery, Tokyo Medical and Dental University, Tokyo, Japan.
authors: Tomokazu
authors: T
authors: Masaoka
authors: Department of Orthopaedic and Spinal Surgery, Tokyo Medical and Dental University, Tokyo, Japan.
authors: Tsuyoshi
authors: T
authors: Yamada
authors: Department of Orthopaedic and Spinal Surgery, Tokyo Medical and Dental University, Tokyo, Japan.
authors: Xuetao
authors: X
authors: Wei
authors: Department of Orthopaedic and Spinal Surgery, Tokyo Medical and Dental University, Tokyo, Japan.
authors: Hiroaki
authors: H
authors: Yasuda
authors: Department of Orthopaedic and Spinal Surgery, Tokyo Medical and Dental University, Tokyo, Japan.
authors: Toshitaka
authors: T
authors: Yoshii
authors: HOYA Technosurgical Corporation, Tokyo, Japan.
authors: Yuko
authors: Y
authors: Kozaka
authors: HOYA Technosurgical Corporation, Tokyo, Japan.
authors: Tomoji
authors: T
authors: Takayama
authors: HOYA Technosurgical Corporation, Tokyo, Japan.
authors: Masahiro
authors: M
authors: Hirano
authors: Department of Orthopaedic and Spinal Surgery, Tokyo Medical and Dental University, Tokyo, Japan.
authors: Atsushi
authors: A
authors: Okawa
authors: Department of Orthopaedic Research and Development, Tokyo Medical and Dental University, Tokyo, Japan.
authors: Shinichi
authors: S
authors: Sotome
mesh_terms: D000818:Animals; D055396:Bone Morphogenetic Protein 2 / Q000494:pharmacology / Q000627:therapeutic use*; D001861:Bone Regeneration / Q000187:drug effects; D003094:Collagen / Q000494:pharmacology / Q000627:therapeutic use*; D004195:Disease Models, Animal; D017886:Durapatite / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D010007:Osteochondritis / Q000601:surgery*; D011817:Rabbits; D023822:Tissue Engineering; D016896:Treatment Outcome; D014945:Wound Healing / Q000187:drug effects
chemical_list: D055396:Bone Morphogenetic Protein 2; D003094:Collagen; D017886:Durapatite
keywords: Bone morphogenetic protein; Osteochondral repair; Porous hydroxyapatite collagen; Scaffold