Group B streptococcus exploits vaginal epithelial exfoliation for ascending infection

Area of Science:

• Reproductive biology
• Microbiology
• Infectious disease

Background:

• Preterm birth and stillbirth affect 13% of pregnancies, often due to in utero infections by vaginal microbes.
• The mechanisms by which vaginal microbes ascend to the uterus remain largely unknown.

Purpose of the Study:

• To elucidate the mechanisms of ascending infection by vaginal microbes, specifically group B Streptococcus (GBS).
• To investigate the role of vaginal exfoliation in GBS ascending infection and its impact on pregnancy outcomes.

Main Methods:

• Utilized in vitro and murine models to study vaginal colonization and ascending infection.
• Investigated GBS-induced vaginal epithelial exfoliation through integrin and β-catenin signaling pathways.

Main Results:

• GBS induces vaginal epithelial exfoliation, which enhances bacterial dissemination and ascending infection.
• Unlike other microbes, exfoliation did not reduce GBS colonization.
• Inhibiting exfoliation decreased ascending infection and improved pregnancy outcomes.

Conclusions:

• Vaginal exfoliation can promote ascending microbial infection rather than preventing colonization.
• This study reveals a novel mechanism by which GBS contributes to adverse pregnancy outcomes.