TLR-Mediated Preterm Birth in Response to Pathogenic Agents

Figure 1

Roads to Preterm. Birth pathogens may enter the placental blood supply via systemic circulation due to previous or current onset of infection. Murine models where intraperitoneal injections are employed are utilized to mimic maternal systemic infection in order to study the ability of a pathogen to activate decidual immunity. Data presented in this paper demonstrate that systemic infections correlate to TNF-𝛼 -dependent immune responses that ultimately induce preterm birth. In contrast, intrauterine ascending infections occur when a pathogen ascends the uterine cavity via the vaginal tract. Surgical procedures in mice, rats, and rabbits have mimicked uterine cavity infections through intrauterine infusion of pathogens directly into the amniotic sac or between two placental units. Importantly, data summarized here demonstrate that pathogens introduced through intrauterine ascension do not tend to activate a TNF-𝛼 -driven axis to induce preterm birth.