The Placental Barrier: From Fundamental Mechanisms to Clinical Implications

Dear Colleagues,

The placental barrier is a dynamic and essential interface that ensures the proper exchange of gases, nutrients, and waste between mother and fetus, as well as mediating endocrine signals and immune processes throughout pregnancy. Its formation begins shortly after blastocyst implantation and involves intricate coordination between maternal and fetal tissues, and it is involved in several pathologies that affect maternal and fetal health.

This Special Issue invites original research, reviews, and short communications on all aspects of the placental barrier, including (but not limited to) the following:

• Morphogenesis and Development:
• Implantation and trophoblast differentiation;
• Formation of placental villi;
• Vascularization and establishment of maternal–fetal circulation.
• Structural, Molecular Composition and Function:
• Cellular layers and extracellular matrix remodeling;
• Signaling pathways (e.g., Wnt, Notch, BMP4, Syncytins, hCG, MMPs);
• Immunological and endocrine functions in normal and pathological conditions.
• Different Models to Study the Placental Barrier and Their Diseases:

• In vitro studies;
• Animal models;
• Ultrasound and MRI.

• Clinical and Translational Perspectives:
• Pathological conditions such as pre-eclampsia, IUGR, prematurity, and placenta accreta spectrum;
• Mechanisms of vertical transmission and infections (e.g., CMV, malaria, toxoplasmosis, Chagas disease);
• Involvement in the Developmental Origins of Health and Disease (DOHaD), including postnatal cardiovascular and metabolic outcomes.

We are particularly interested in interdisciplinary submissions that connect developmental biology, immunology, pharmacology, pathology, and clinical medicine.

Other Potential Submission Topics:

• Barrier permeability and transport mechanisms;
• Molecular diagnostics and biomarkers;
• Novel models (in vitro, in vivo, organoids);
• Drug passage and placental pharmacokinetics.

We welcome contributions that explore this vital structure from molecular, cellular, physiological, and clinical perspectives. Join us in deepening understanding of the placental barrier and its central role in maternal–fetal health.

Dr. Ricardo Emilio Fretes
Dr. María I. De La Calle
Guest Editors

Manuscript Submission Information

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