Immunobiology of Acute Chorioamnionitis

Abstract

Acute chorioamnionitis is characterized by neutrophilic infiltration and inflammation at the maternal fetal interface. It is a relatively common complication of pregnancy and can have devastating consequences including preterm labor, maternal infections, fetal infection/inflammation, fetal lung, brain, and gastrointestinal tract injury. In this review, we will discuss current understanding of the pathogenesis, immunobiology, and mechanisms of this condition. Most commonly, acute chorioamnionitis is a result of ascending infection with relatively low-virulence organisms such as the Ureaplasma species. Furthermore, recent vaginal microbiome studies suggest that there is a link between vaginal dysbiosis, vaginal inflammation, and ascending infection. Although less common, microorganisms invading the maternal-fetal interface via hematogenous route (e.g., Zika virus, Cytomegalovirus, and Listeria) can cause placental villitis and severe fetal inflammation and injury. We will provide an overview of the knowledge gleaned from different animal models of acute chorioamnionitis and the role of different immune cells in different maternal-fetal compartments. Lastly, we will discuss how infectious agents can break the maternal tolerance of fetal allograft during pregnancy and highlight the novel future therapeutic approaches.

Innate Immune Mechanisms to Protect Against Infection at the Human Decidual-Placental Interface

“…However, some pathogens can escape antimicrobial strategies at the cervix and ascend to the uterus, where they can bypass the fetal membranes and lead to the inflammation of the membranes- also known as chorioamnionitis- and infection of the amniotic fluid ( 7 , 8 ). Pathologic and immune features of chorioamnionitis and intra-amniotic infection are generally associated with bacterial invasion and inflammation [refer to ( 8 , 9 ) for a comprehensive review on these mechanisms]. Here, we focus on infections and innate immune mechanisms at the uterine-placental interface—cases (i) and (ii) ( Figure 1 ).…”

The Inflammatory Milieu of Amniotic Fluid Increases with Chorio-Deciduitis Grade in Inflammation-Restricted to Choriodecidua, but Not Amnionitis, of Extra-Placental Membranes

“…Nevertheless, it is well-known that intra-amniotic micro-organisms incite an IAIR resulting in an increase of chemokine level (e.g., CXCL6, IL-8) and chemotactic gradient [3,7,14,15]. Ultimately, this phenomenon causes amniotrophic outside-in neutrophil migration within EPM [7,14]. The extent Our previous studies demonstrated IAIR increased according to the progression of inflammation in the detailed subdivisions of each placental compartment [25][26][27][28][29][30][31].…”

Corioamnionitis, definición, métodos de diagnóstico y repercusión clínica

“…Los resultados de las pruebas de laboratorio pueden ayudar a descartar el diagnóstico de corioamnionitis, especialmente cuando los signos y síntomas clínicos son equívocos. La leucocitosis materna (definida de manera diversa como WBC> 12,000 / mm3 o> 15,000/mm3) o la presencia de un desplazamiento a la izquierda o una bandemia (> 9%) a menudo respaldan el diagnóstico de corioamnionitis (12). Se informa leucocitosis en aproximadamente el 70-90% de los casos de corioamnionitis clínica.…”