Fig. 5. Innate peptides abundantly and constitutively secreted by the squamous mucosa lining the lower gynecologic tract exhibit a positive effect on Lactobacillus survival.

a Schematic illustration of the different steps involved in bacterial colony detection and count. b Systematic analysis of both defensin and “defensin-like” peptide activity on predominant bacterial species detected in normal (L. crispatus, L. jensenii and L. iners) and pathological (BV) (G. vaginalis) conditions. Results represent the means ± SEM of three (L. crispatus, L. jensenii and L. iners) or five (G. vaginalis) independent experiments. c Effect of reducing environment on antimicrobial/protective activity of tested innate peptides. Results represent the means ± SEM of four (L. jensenii and G. vaginalis), five (L. iners) or six (L. crispatus) independent experiments. The positive effect on Lactobacillus survival displayed by the most abundant innate peptides secreted by cervical/vaginal mucosa (elafin and S100A7) was also assessed in both potassium phosphate buffer (KPB) (d) and acidic (pH 5.8) conditions (e). For each experiment, peptides were incubated with bacteria for 6 h. Results represent the means ± SEM of four independent experiments. P values were determined using one-way ANOVA followed by Dunnett’s multiple comparison post-hoc test (c, e). ns: not significant (p > 0.1). Source data are provided as a Source Data file.