Microglial process convergence on axonal segments in health and disease
Savannah D Benusa1, Audrey D Lafrenaye1
1Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA 23298, USA.
Neuroimmunology and Neuroinflammation
|May 19, 2021
Summary
Microglia interact with axons, impacting neuronal networks and axonal integrity. These interactions change in diseases like multiple sclerosis and traumatic brain injury, affecting specific axonal regions.
Area of Science:
- Neuroscience
- Cell Biology
- Immunology
Background:
- Microglia are key immune cells in the central nervous system.
- Microglia dynamically interact with neurons, influencing network development and function.
- Emerging evidence suggests microglia physically interact with axonal domains, potentially modulating neuronal activity.
Purpose of the Study:
- To review microglial process interactions with axonal segments.
- To analyze associations with various axonal domains.
- To explore differences in these interactions in multiple sclerosis (MS) and traumatic brain injury (TBI).
Main Methods:
- Literature review of studies on microglial-axonal interactions.
- Analysis of microglial contact with specific axonal segments (axon initial segment, node of Ranvier).
- Comparison of interaction patterns in development, adulthood, MS, and TBI.
Main Results:
- Microglial-axonal contacts are present from development through adulthood.
- Disease states like MS and TBI show altered microglial-axonal contacts.
- MS involves enhanced contact at the axon initial segment and node of Ranvier; TBI alters contacts at injury sites and the axon initial segment.
Conclusions:
- Microglial-axonal interactions play a role in regulating axonal integrity in both health and disease.
- Understanding these interactions is crucial for deciphering their functional consequences and molecular mechanisms in neurological disorders.
- Differential microglial-axonal engagement in MS and TBI highlights disease-specific roles.
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