About this Research Topic
Successful pregnancy requires a protective intrauterine environment, which ensures the optimal development of the fetus. The fetal membranes line the internal surface of the pregnant uterus and are critically important for maintaining the conditions needed for fetal health. The innermost layer is the amnion membrane, which is in contact with the amniotic fluid and maintains the structural integrity of the gestational sac by its mechanical strength. The underlying chorion laeve is fused to the decidua as part of the maternal-fetal interface. The interaction of the chorion and the decidua controls the innate and adaptive immune systems of the mother locally in the uterus, which is critical for tolerating the semi-allogeneic fetus. As pregnancy advances to term the fetal membranes and the decidua undergo a transformation weakening these pro-pregnancy functions and promoting a proinflammatory phenotype with decreased immune tolerance and reduced membrane strength. The remodeled fetal membranes are prone to rupture and produce uterotonic factors, which reach the myometrium and stimulate contractions. These changes lead to labor and birth.
Although much is known about the histological structure, cellular composition and functional properties of the fetal membranes in normal and pathological pregnancies, the mechanisms that maintain the phenotype supporting pregnancy and cause the transition to a state promoting birth at the accurate time are poorly understood. As a consequence, pregnancy complications such as preterm labor, preterm membrane rupture (pPROM), post-term birth and dysfunctional labor are still prevalent. Evidently, more research into fetal membrane biology is needed to generate the knowledge that will make possible the effective prevention, timely diagnosis and safe therapy of these intractable pregnancy complications. The goal of this Research Topic is to present a collection of papers that highlight the role of the fetal membranes in normal gestation, at birth, in pathological pregnancies and as an emerging source of stem cells and transplanted material. Proposing new concepts and hypotheses, disseminating technical innovations and advocating paradigm shifts will strengthen interest and stimulate further research in this important field of study.
In this Research Topic issue we include articles that summarize the present state of knowledge of fetal membrane (amnion and chorion laeve) structure and function. Contributions describing clinical observations, cellular and molecular changes, in vitro mechanistic studies, new concepts and methodologies are sought. The scope extends to the decidua as the maternal tissue in close contact and regulatory interactions with the fetal membranes. Addressing potential clinical translations and uses are particularly encouraged. Animal models with relevance to human pregnancy are also within the scope of the Topic. The formats include Original Research Articles, Brief Research Reports, concise Reviews, Conceptual Analyses, new Methods, Hypotheses and Perspectives.
The specific themes include, but not limited to:
• Gene expression patterns and phenotype dynamics of fetal membrane and decidua cells during pregnancy
• The role of the fetal membranes in controlling the endocrine/paracrine environment in the uterus
• The role of fetal membranes and decidua in regulating innate- and adaptive immune responses in the pregnant uterus
• Mechanical properties of the fetal membranes
• Molecular mechanisms underpinning fetal membrane function at the genetic, epigenetic and cellular signaling levels
• Fetal membranes as sources of stem cells and surgical transplants
Keywords: Amnion, Chorion, Gestation, Parturition, Trophoblast
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.