3D visualization of trans-syncytial nanopores provides a pathway for paracellular diffusion across the human placental syncytiotrophoblast.
iScience
; 25(12): 105453, 2022 Dec 22.
Article
em En
| MEDLINE
| ID: mdl-36387021
ABSTRACT
The placental syncytiotrophoblast, a syncytium without cell-cell junctions, is the primary barrier between the mother and the fetus. Despite no apparent anatomical pathway for paracellular diffusion of solutes across the syncytiotrophoblast, size-dependent paracellular diffusion is observed. Here we report data demonstrating that the syncytiotrophoblast is punctuated by trans-syncytial nanopores (TSNs). These membrane-bound TSNs directly connect the maternal and fetal facing sides of the syncytiotrophoblast, providing a pathway for paracellular diffusion between the mother and fetus. Mathematical modeling of TSN permeability based on their 3D geometry suggests that 10-37 million TSNs per cm3 of placental tissue could explain experimentally observed placental paracellular diffusion. TSNs may mediate physiological hydrostatic and osmotic pressure homeostasis between the maternal and fetal circulations but also expose the fetus to pharmaceuticals, environmental pollutants, and nanoparticles.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
IScience
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Reino Unido