実験動物用マイクロCTを用いたrhBMP-2・アテロコラーゲンゲルによるウサギの顎骨欠損部再建の経時的観察

A rabbit experimental mandibular defect was reconstructed with rhBMP-2 and atelocollagen gel, and examined using μCT (R_mCT, Rigaku mechatronics, Tokyo) in vivo and histological techniques. Using eight rabbits, we made an experimental mandibular defect and filled it with 1% atelocollagen gel including rhBMP-2 10μg (Astellas Pharma Inc.). In μCT observation, the density was slightly elevated at the bone marrow side at day 5, and the phenomenon gradually expanded during the course of this experiment. Histologically, mesenchymal cell proliferation and immature bone formation occurred at one week, and mature bone gradually increased and filled in at four weeks. The histological data suggests that atelocollagen gel is effective as carrier of rhBMP-2. The μCT observation is extremely useful for follow-up of such reconstruction of animal bone defect model.実験小動物に最適化した専用のX線マイクロCT装置(μCT)を用いて,ウサギの実験的顎骨欠損モデルについてアテロコラーゲンゲルを担体とした遺伝子組換え型ヒト骨形成因子(rhBMP)-2による再建過程を経時的に観察した.μCT観察において,5日で骨髄側から僅かであるがX線吸収度の上昇があり,以後拡大を示した.2週以降で骨欠損部全域に亘った.組織学的に,1週では骨髄側からの間葉系細胞の増殖と一部に幼若な骨形成があり,4週で成熟した.rhBMP-2の担体としてアテロコラーゲンゲルを用いた顎骨再建の有効性が示唆され