Long-term microglial phase-specific dynamics during single vessel occlusion and recanalization

Area of Science:

• Neuroscience
• Immunology
• Pathology

Background:

• Vascular occlusion in the brain triggers microglia-induced inflammation, but their precise interaction with blood vessels in these disorders is not fully understood.
• Understanding microglia-blood vessel interactions is crucial for developing effective treatments for cerebrovascular diseases.

Purpose of the Study:

• To investigate the long-term spatiotemporal dynamics of microglia during single vessel occlusion and recanalization.
• To elucidate the mechanisms underlying microglial responses in different phases of vascular occlusion and recanalization.

Main Methods:

• Long-term observation of microglia behavior during induced vessel occlusion and subsequent recanalization.
• Analysis of microglial morphology, migration patterns, proliferation, and gene expression (MHCII).

Main Results:

• Microglia exhibit distinct responses across different phases: acute reaction, rapid diffusion, transition, and chronic effect.
• Fibrinogen triggers microglial clustering and enhances major histocompatibility complex II (MHCII) expression.
• Microglia show unique filament-shaped soma migration, with processes reacting faster than the cell body to occlusion; proliferative microglia redistribute territory.
• Microglial clusters resolve over time, with microglia returning to a resting state morphologically and functionally.

Conclusions:

• This study provides a comprehensive analysis of microglial spatiotemporal dynamics in response to vascular occlusion and recanalization.
• Phase-specific microglial responses suggest that interventions targeting morphological features in distinct phases could be beneficial for treating vascular occlusion-related diseases.