Fetal brain vulnerability to SARS-CoV-2 infection

Area of Science:

• Neuroscience
• Virology
• Immunology

Background:

• Prenatal SARS-CoV-2 transmission and fetal neurodevelopmental consequences remain controversial.
• Evidence suggests potential viral entry into fetal tissues and neurological impacts on neonates.

Purpose of the Study:

• To investigate SARS-CoV-2 transmission to the fetus and its effects on the developing brain.
• To assess the impact of maternal COVID-19 on pregnant mice compared to non-pregnant controls.

Main Methods:

• Utilized a human ACE2 knock-in mouse model for prenatal SARS-CoV-2 infection studies.
• Examined viral transmission, fetal tissue infection, and neurological changes (gliosis).
• Compared disease severity and immune response in pregnant versus non-pregnant infected mice.

Main Results:

• SARS-CoV-2 transmitted to fetal tissues, including the brain, primarily affecting male fetuses.
• Infection observed in fetal vasculature, neurons, glia, and choroid plexus; no viral replication or cell death noted.
• Infected offspring showed developmental differences and gliosis; pregnant mice had more severe COVID-19 with brain dissemination but blunted IFN response.

Conclusions:

• Prenatal SARS-CoV-2 exposure poses risks for fetal neurodevelopment and can lead to more severe maternal illness.
• Findings highlight potential neurological complications and pregnancy complications following maternal COVID-19.