Figure 3.

GBS exploits epithelial-mesenchymal transition (EMT) and vaginal epithelial exfoliation to permit ascending infection. During vaginal infection, GBS binds integrins on the epithelial surface and activates integrin signaling that results in the breakdown of adherens junctions. Displaced β-catenin translocates to the nucleus, activating transcriptional changes of β-catenin targets associated with EMT. Expression of these transcripts in vivo leads to vaginal epithelial exfoliation, which facilitates GBS ascension to the uterus and is associated with increased risk for microbial invasion of the amniotic cavity and preterm birth.