Verification of the inhibitive capacity by the salivary protein derived-peptide specific secretory IgA antibody on periodontal disease-pathogenic bacteria colonization.

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K12034
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Social dentistry
• Research Institution: Osaka Dental University
• Principal Investigator: Takayama Yuki (藤井由希) 大阪歯科大学, 歯学部, 講師(非常勤) (20790322)
• Co-Investigator(Kenkyū-buntansha): 三宅 達郎 大阪歯科大学, 歯学部, 教授 (40200141) ; 片岡 宏介 大阪歯科大学, 歯学部, 准教授 (50283792)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: ヒト唾液タンパク / 歯周病細菌 / DNA粘膜アジュバント / 経鼻ワクチン / 唾液分泌型IgA抗体 / 初期付着阻害

Outline of Final Research Achievements

We previously have reported that human salivary acidic proline-rich proteins (PRPs) and statherin possessed specific binding domains for interaction with Porphyromonas gingivalis (Pg) fimbriae. Therefore, we artificially synthesized peptides (prp21, stat23) that is equivalent to the respective binding domain. When mice were given nasally prp21 or stat23 as an antigen with double DNA adjuvant, the salivary antigen-specific IgA antibodies to prp21 or stat23 were significantly induced compared with those of mice administered nasally with an antigen alone.
In addition, when mice were simultaneously given prp21 and stat23 with double DNA adjuvant, the collected saliva inhibited Pg binding to human whole saliva-coated hydroxyapatite beads by approximately 60% compared with those of mice administered nasally with an antigen alone.

Free Research Field

口腔衛生学

Academic Significance and Societal Importance of the Research Achievements

これまで歯周病予防ワクチン開発は、歯周病細菌表層の線毛やLPSという細菌由来の抗原を実験動物に全身投与、もしくは粘膜アジュバントとともに投与する粘膜ワクチンが検討されてきたが、持続・安定したワクチン効果、安全性の面などから実現には至っていない。
本研究成果は、ヒトタンパク由来のprp21抗原とstat23抗原に対する特異的SIgA抗体を応用した、歯周病発症予防のための針不要の能動免疫型経鼻ワクチン開発に繋がると考える。
また、ペプチドprp21およびstat23はPg線毛に直接結合することでペリクルへの菌体初期付着を阻害することから、受動免疫型経口ワクチンの基剤としての可能性も考えられる。