Development of new transplantation method for studying the rodent incisor development

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K11848
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Periodontology
• Research Institution: Fukuoka Dental College
• Principal Investigator: SAKAGAMI Ryuji 福岡歯科大学, 口腔歯学部, 教授 (50215612)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: セメント芽細胞 / 上皮間葉転換 / apical bud / Hertwig上皮鞘

Outline of Final Research Achievements

Rodent mandibular incisors have a unique epithelial tissue stem cell structure ‘apical bud’ that allows teeth to grow throughout the lifetime of the rodent. We had succeeded in making an animal experimental model that enables replacing the living wild type mise apical buds with GFP-positive mise ones. The tissue showed anatomically normal structure and some of the GFP-positive cells were observed as cementblast-like cells inside cementum. The experimental protocol has further tuned up as isolating pure apical bud cells from GFP-positive mouse, dispersing cells, and then injecting them to the periodontal ligament space of the wild type mouse. The injected cells survived in the periodontal ligament space and some were observed in cementum. These observations could be important findings that leads to understanding of tooth development and tissue regeneration.

Free Research Field

歯周病学

Academic Significance and Societal Importance of the Research Achievements

歯の発生と歯根膜の恒常性維持のメカニズムに関しては、未だに最も基本的な部分で未解明な点が多々ある。近年、Hertwig上皮鞘の細胞（HERS細胞）が上皮間葉転換を起こしてセメント芽細胞（歯根表面で骨につながる組織を作る細胞）に分化するという説が提唱されている。しかし、証明手段が無かったために未だ確証が得られていない。われわれの開発した動物実験の手法により、メカニズムの解明が期待される。将来的にはHERS細胞をソースとした、画期的な歯の発生や歯周組織再生療法へと発展する可能性がある。