Synthetic bacterial consortia transplantation attenuates vaginal inflammation and modulates the immune response in a mouse model of Gardnerella vaginalis-induced bacterial vaginosis

This study aimed to evaluate the efficacy of synthetic bacterial consortia transplantation (SBCT) and compare it with VMT (vaginal microbiota transplantation) in a mouse model of <i>Gardnerella vaginalis</i>-induced Bacterial vaginosis (BV). A murine model of <i>G. vaginalis</i>-induced BV was established, and mice were treated with SBCT, VMT, or saline. Histopathological changes, inflammatory cytokine levels, pro-inflammatory biomarker expression, helper T cell transcription factor expression, and vaginal microbiota composition were assessed. SBCT and VMT effectively suppressed <i>G. vaginalis</i> growth, reduced inflammation, and restored vaginal microbiota diversity. Both treatments attenuated epithelial damage, downregulated pro-inflammatory cytokines (IL-1β and IL-8), and upregulated the anti-inflammatory cytokine IL-10. SBCT and VMT also inhibited NF-κB activation, suppressed IL-17 expression, and enhanced Foxp3 expression in vaginal tissues. SBCT is a promising therapeutic approach for treating BV, as it effectively modulates the immune response and restores vaginal microbiota diversity in a mouse model of <i>G. vaginalis</i>-induced BV.