Maternal microbiota communicates with the fetus through microbiota-derived extracellular vesiclesOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
Researchers investigated whether extracellular vesicles (EVs), membrane-bound particles secreted by gut bacteria, are present in the fetal environment during healthy pregnancy and whether maternal gut microbiota EVs can cross biological barriers to reach the fetus.
How was it studied?
Amniotic fluid (26 samples) and fecal samples (25 samples) from pregnant women undergoing cesarean section were analyzed by nanoparticle tracking, electron microscopy, proteomics, and 16S rRNA gene sequencing. Fluorescently labeled human fecal EVs were also injected into pregnant mice to track whether they reached the fetus.
What did they find?
Bacterial EVs were detectable in amniotic fluid and shared 79 bacterial proteins with maternal fecal EVs, dominated by the same phyla (Bacteroidetes, Firmicutes, Proteobacteria, Actinobacteria). In pregnant mice, labeled human fecal-derived EVs accumulated in the fetuses within 24 hours of injection.
Why it matters
The findings suggest maternal gut microbiota communicates with the fetus via EVs rather than live bacteria, offering a possible mechanism for priming the fetal immune system ahead of gut colonization at birth.