The Cervicovaginal Microbiota-Host Interaction Modulates Chlamydia trachomatis Infection

Area of Science:

• Microbiology
• Immunology
• Gynecology

Background:

• The cervicovaginal microbiota is crucial for protecting against Chlamydia trachomatis, a prevalent sexually transmitted infection (STI).
• The precise mechanisms by which Lactobacillus species confer protection remain largely unknown.
• Understanding these mechanisms is vital for developing novel therapeutic strategies.

Purpose of the Study:

• To investigate the impact of different Lactobacillus species on Chlamydia trachomatis infection in a 3D cervical epithelium model.
• To elucidate the molecular mechanisms underlying Lactobacillus-mediated protection against C. trachomatis.
• To identify specific Lactobacillus-derived factors responsible for conferring protection.

Main Methods:

• Metataxonomic analysis of cervicovaginal microbiota from C. trachomatis-infected women.
• In vitro infection of a 3D cervical epithelium model with C. trachomatis.
• Assessment of Lactobacillus species' impact on C. trachomatis infection and epithelial cell proliferation.
• Transcriptomic analysis to identify host-pathway modulations.

Main Results:

• Lactobacillus species producing d(-) lactic acid demonstrated significant long-term protection against C. trachomatis infection.
• Lactobacillus iners, which does not produce d(-) lactic acid, was associated with reduced protection.
• Decreased epithelial cell proliferation correlated with the prolonged protective effect observed.
• Epigenetic modifications, particularly involving histone deacetylase pathways, were identified as key in host-microbiota crosstalk.

Conclusions:

• The cervicovaginal microbiota, specifically d(-) lactic acid-producing Lactobacillus species, plays a fundamental role in protecting against Chlamydia trachomatis infection.
• Epigenetic modifications mediated by histone deacetylase pathways are integral to this protective mechanism.
• These findings provide a mechanistic understanding that could lead to microbiome-based interventions for STIs and improved vaginal health.