[New findings about vaginal bacterial flora]

Area of Science:

• Microbiology
• Immunology
• Genetics

Background:

• The vaginal ecosystem's composition and its role in host defense are crucial for reproductive health.
• Traditional culture methods limit the comprehensive analysis of vaginal microflora.
• Understanding the interplay between vaginal flora, host genetics, and immunity is essential for clinical practice.

Purpose of the Study:

• To update knowledge on the vaginal ecosystem, focusing on non-cultivation bacterial identification methods.
• To review the predominant Lactobacillus species in normal vaginal flora and their variations.
• To explore the influence of host genetics on immune responses within the vaginal environment.

Main Methods:

• A comprehensive literature search of Medline (PubMed) from 1997-2009 was conducted.
• Selection of informative articles focusing on the vaginal microbiome and host-pathogen interactions.
• Emphasis on non-culture techniques, specifically gene amplification, for bacterial identification.

Main Results:

• Non-culture techniques provide a comprehensive analysis of the vaginal ecosystem.
• Lactobacillus species (L. crispatus, L. inners, L. gasseri) are predominant in most reproductive-age women.
• Variations include the absence of Lactobacillus, with substitution by other lactic acid-producing bacteria (Atobium, Megasphaera, Leptotrichia).
• Vaginal flora and immune mechanisms suppress pathogen proliferation through lactic acid, antimicrobial compounds, and immune cell activation (Toll-like receptors, cytokine production, antibody generation).

Conclusions:

• Vaginal flora composition and immune mechanisms are critical host defenses.
• Current criteria for normal and abnormal vaginal flora require re-evaluation.
• Host genetic variations may explain differences in vaginal flora composition and immune responses.
• Integrating this knowledge into clinical practice can improve gynecological and obstetrical patient care.