Mechanisms of Vaginal Homeostasis by Vaginal Bacterial Flora

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K18177
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 56040:Obstetrics and gynecology-related
• Research Institution: Nihon University
• Principal Investigator: TAKADA Kazuhide 日本大学, 医学部, 助教 (60848711)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 腟細菌叢 / 子宮内細菌叢 / Lactobacillus

Outline of Final Research Achievements

Bacterial flora in the female reproductive organs plays an important role in homeostasis. When culture supernatants of Lactobacillus strains, mainly vaginally derived, were added to each other, almost no significant changes in bacterial growth were observed. This suggests that the mechanism by which the vaginal flora becomes Lactobacillus-dominated may be due to host selection pressure rather than competition among the bacteria. Culture supernatants of Gardnerella vaginalis also significantly enhanced the secretion of the antimicrobial peptide Elafin from cervical epithelial cells. In the endometrial flora, viable L. crispatus and culture supernatants significantly promoted trophoblast invasion, which may affect implantation.

Free Research Field

生殖免疫

Academic Significance and Societal Importance of the Research Achievements

腟内細菌叢の乱れは、細菌性腟症など様々な原因となる。治療法の一つとしてプロバイオティクスがあるが、どの菌種がどのような機序で作用しているか、また組織に定着しているかは不明な点が多い。そのため、理想的とされるLactobacillus主体の細菌叢はどのようなメカニズムで維持されるのか、また病原菌はどのような影響を粘膜免疫に及ぼすかの一端を明らかにした本研究は、この分野の理解促進につながる。また子宮内細菌叢は健常人の菌種構成すらコンセンサスに至っておらず、今回の研究成果は子宮内細菌叢の役割の理解および、将来の適切な細菌叢介入手段の検討に寄与する。