Isolation and identification methods for Helicobacter pylori from human oral cavities and investigation of its transmission pattern

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K12023
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Social dentistry
• Research Institution: Nihon University
• Principal Investigator: TSUZUKIBASHI Osamu 日本大学, 松戸歯学部, 講師 (80333110)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: Helicobacter pylori / 胃・十二指腸潰瘍 / 胃がん / 選択培地 / 口腔 / 感染様式

Outline of Final Research Achievements

Helicobacter pylori causes gastric and peptic ulcers, and also gastric cancer. Recently, it was frequently reported that H. pylori was detected from human oral cavities. The aim of this study was to establish of the isolation and identification methods for H. pylori from human oral cavities, and investigate its transmission pattern.
A selective medium, HPSM, for the isolation of H. pylori from oral cavities was developed in this study. Also, PCR primer for the identification and detection of H. pylori was designed. HPSM and PCR method using the primers designed in this study were useful for the isolation and identification of H. pylori from human oral cavities. H. pylori in 200 saliva samples was detected at 1.5%. Moreover, H. pylori 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 H. pylori.

Free Research Field

口腔細菌学

Academic Significance and Societal Importance of the Research Achievements

近年、PCR法を用いた菌の検出方法により、唾液や歯石などの口腔試料からもピロリ菌が検出されていることから、胃内のみならず口腔内もピロリ菌の生息部位である可能性が示唆されている。さらに、唾液や歯石などから検出されるために、離乳食として親が噛み砕いた食品を乳幼児に食べさせる行為や、家族内で共通食器の使用によって、ピロリ菌を口腔に保菌している親の唾液などを介して子供にピロリ菌が感染するという家族内での感染・伝播の可能性も示唆されている。本研究により、ピロリ菌の感染様式が詳細に解明されれば、感染防止策の確立に繋がり胃癌発症等の減少に寄与するものと考えられる。