Variability of the response of human vaginal Lactobacillus crispatus to 17β‑estradiol

By Maximilien Clabaut
Amine M. Boukerb
Amine Ben Mlouka
Amandine Suet
Ali Tahrioui
Julien Verdon
Magalie Barreau
Olivier Maillot
Agathe Le Tirant
Madina Karsybayeva
Coralie Kremser
Gérard Redziniak
Cécile Duclairoir‑Poc
Chantal Pichon
Julie Hardouin
Pascal Cosette
Sylvie Chevalier
Marc G. J. Feuilloley

We previously showed that the physiological concentration of 17β‑estradiol in the vaginal environment is sufficient to affect the membrane dynamics and adhesion phenotype of the Lactobacillus crispatus strain CIP104459. However, L. crispatus is a heterogeneous species. Here, we investigated the effect of 17β‑estradiol on the recently isolated L. crispatus vaginal strain V4, related to a cluster distant from CIP104459 and at the limit of being a different subspecies. Grown in the same medium, the two strains expressed a highly similar pool of proteins. However, in contrast to CIP104459, L. crispatus V4 showed high aggregation potential and 17β‑estradiol promoted this phenotype. This effect was associated with large changes in cell‑surface polarity and Lewis acid/base properties. In addition, we observed no effect on the membrane dynamics, contrary to CIP104459. These results can be explained by differences in the properties and organization of the S layer between the two strains. However, as for CIP104459, 17β‑estradiol increased biosurfactant production of L. crispatus V4 and their adhesion to vaginal cells. This suggests that 17β‑estradiol agonists would be valuable tools to favor a stable re‑implantation of L. crispatus in the vaginal mucosa.