A starring role for microglia in brain sex differences.

Area of Science:

• Neuroimmunology
• Developmental Neuroscience
• Neurobiology

Background:

• Microglia are the brain's resident immune cells, traditionally known for their roles in surveillance and response to injury.
• Emerging research highlights microglia's active participation in healthy brain functions like synaptic plasticity and cell proliferation.
• Microglia are critical during early brain development, influencing sexual differentiation through phagocytosis and secretion of neuroactive molecules.

Purpose of the Study:

• To review the multifaceted roles of microglia in normal brain development.
• To explore how developmental neuroimmune disruptions contribute to brain-based disorders.
• To examine sex-based differences in microglial function and their implications for neuropsychiatric and neurological disease incidence.

Main Methods:

• This is a review article, synthesizing existing research.
• It analyzes studies on microglial roles in neurodevelopment and neuroinflammation.
• The review integrates findings on sex-specific neuroimmune signaling.

Main Results:

• Microglia are essential for fundamental brain processes, including development and synaptic connectivity.
• Alterations in the neuroimmune environment during development are linked to the etiology of brain disorders.
• Significant sex-based differences exist in microglial function and neuroimmune signaling across the lifespan.

Conclusions:

• Microglia are key regulators of brain development and function, extending beyond their immune roles.
• Developmental neuroimmune dysregulation is a critical factor in the pathogenesis of various brain disorders.
• Understanding sex-specific microglial roles is crucial for explaining differential disease susceptibility between males and females.