Pregnancy-induced maternal microchimerism shapes neurodevelopment and behavior in mice

Area of Science:

• Neuroscience
• Developmental Biology
• Immunology

Background:

• Prenatal development critically influences lifelong brain function and mental health.
• Maternal microchimeric cells (MMc) transfer from mother to fetus during pregnancy.
• The role of MMc within the fetal brain remains largely unknown.

Purpose of the Study:

• To investigate the function of maternal microchimeric cells (MMc) in the developing fetal brain.
• To determine the impact of MMc on brain development, circuit formation, and behavioral maturation.

Main Methods:

• Utilized a mouse model to study MMc in the fetal brain.
• Analyzed MMc gene expression, focusing on sensome markers.
• Assessed the effects of MMc on microglia homeostasis, synaptic elimination, and neural circuit activity.

Main Results:

• MMc in the fetal brain exhibit a unique sensome marker signature.
• MMc were found to control microglia homeostasis and prevent excessive presynaptic elimination.
• MMc facilitate oscillatory entrainment of prefrontal-hippocampal circuits and support behavioral maturation.

Conclusions:

• Maternal microchimeric cells (MMc) play an active, functional role in fetal brain development.
• MMc are essential for establishing optimal conditions for healthy brain function and mental health later in life.
• MMc are not a byproduct of placental transfer but a vital developmental mechanism.