摘要：SummaryDuring gestation, the cervical mucus plug (CMP) acts to seal the cervical canal. Pilot studies in humans have suggested that a porous CMP may increase the risk of uterine infection and preterm birth. We examined the gel-forming content of the mouse vagina and the CMP. We experimentally infected pregnant mice by intravaginal administration of pathogens related to preterm birth in humans. We found that the epithelium in both the vagina and cervical canal of pregnant mice produced the two gel-forming mucins Muc5b and Muc5ac. The CMP was porous in Muc5b-deficient mice for which intravaginal administration ofEscherichia coliO 55 led to the activation of an inflammatory response in the uterus and 100% preterm births. The pathogen was found in the mucus plug and uterus. This study shows that Muc5b is essential for thein vivobarrier function and the prevention of uterine infections during gestation.Graphical abstractDisplay OmittedHighlights•Muc5b and Muc5ac are the main gel-forming mucins of the mouse vagina and cervical canal•During pregnancy, a cervical mucus plug (CMP) is formed and seals the cervical canal•Muc5b-deficient CMP is highly porous•Inflammation following vaginal infection causes preterm birth in Muc5b-deficient miceBiological sciences; Natural sciences; Reproductive medicine; Rodent reproduction
