Isolation and identification methods of Klebsiella pneumoniae associated with onset of Crohn disease

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K10300
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 57080:Social dentistry-related
• Research Institution: Nihon University
• Principal Investigator: TSUZUKIBASHI Osamu 日本大学, 松戸歯学部, 准教授 (80333110)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: Klebsiella pneumoniae / クローン病 / 炎症性腸疾患 / 分離・同定 / 口腔細菌

Outline of Final Research Achievements

Recently, Klebsiella pneumoniae is related to the onset of inflammatory bowel disease including the Crohn disease. It was frequently reported that K. pneumoniae was detected from human oral cavities. The aim of this study was to establish of the isolation and identification methods for K. pneumoniae from human oral cavities and investigate its transmission pattern. A selective medium, OKPSM, for the isolation of K. pneumoniae from oral cavities was developed in this study. Also, PCR primer for the identification and detection of K. pneumoniae was designed. OKPSM and PCR method using the primers designed in this study were useful for the isolation and identification of K. pneumoniae from human oral cavities. K. pneumoniae in 50 saliva samples was detected at 6.0%. Moreover, K. pneumoniae isolates showed same genotypes on AP-PCR using OPA-07 primer. These results indicated that human oral cavities were not suitable for the habitats of K. pneumoniae.

Free Research Field

口腔細菌

Academic Significance and Societal Importance of the Research Achievements

口腔試料から本菌を確実に検出・分離するための選択培地を開発することにより、K. pneumoniaeの真の口腔内分布を調査することが可能となる。近年の研究報告により本菌に脚光が集まってきた現在、申請者がこれまでに開発されていない本菌の選択培地を開発し、これまでに詳細に解明されていない口腔内分布を解明することは非常に重要なことであり、また独自性をもった研究テーマであると考えた。また、本菌が口腔常在菌ならば本菌を除菌するのに有効な薬剤を探索し、もし口腔常在菌でないのであれば様々な環境試料を集め本選択培地を用いて本菌を検出することによって感染源・感染経路を特定することは非常に有意義なことである。