Maternal Immune Activation Alters Fetal Brain Development and Enhances Proliferation of Neural Precursor Cells in...

Area of Science:

• Neuroscience
• Developmental Biology
• Immunology

Background:

• Maternal immune activation (MIA) is linked to offspring neurodevelopmental and psychiatric disorders.
• PolyI:C exposure in rodents models MIA, but acute prenatal effects are understudied.

Purpose of the Study:

• To investigate acute transcriptomic and developmental changes in the conceptus following maternal PolyI:C exposure.
• To characterize early fetal brain alterations induced by MIA.

Main Methods:

• RNA-Sequencing of rat conceptuses after maternal PolyI:C administration during early gestation.
• Analysis of fetal brain structure and neural precursor cell (NPC) behavior.

Main Results:

• MIA induced robust upregulation of antiviral inflammatory genes and downregulation of nervous system development genes.
• Prenatal MIA led to thicker cortical regions in fetuses and increased NPC self-renewal.
• Notch1 and delta-like ligand 1 expression increased, suggesting altered NPC maintenance.

Conclusions:

• Maternal immune activation triggers rapid, profound changes in prenatal gene expression and fetal brain development.
• These early alterations in neurodevelopmental pathways may contribute to long-term behavioral deficits.