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Induction of Experimental Autoimmune Encephalomyelitis in Mice and Evaluation of the Disease-dependent Distribution of Immune Cells in Various Tissues
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Monocyte-mediated entry of pathogens into the central nervous system

A E Williams1, W F Blakemore

  • 1Department of Paediatrics, John Radcliffe Hospital II, University of Oxford.

Neuropathology and Applied Neurobiology
|October 1, 1990
PubMed

Insights

Microglia originate from monocytes that enter the central nervous system (CNS). These monocytes transform into microglia, potentially serving as carriers for pathogens causing CNS diseases.

Area of Science:

  • Neuroimmunology
  • Cell Biology
  • Pathogenesis

Background:

  • The cellular origin of microglia, the resident immune cells of the central nervous system (CNS), has been a long-standing question in neuroscience.
  • Understanding microglia origin is crucial for investigating CNS diseases and immune responses within the brain.

Purpose of the Study:

  • To clarify the origin of microglia in the normal central nervous system.
  • To investigate the role of monocytes in microglia differentiation and CNS entry.

Main Methods:

  • The study likely involved tracking cell populations and their differentiation within the CNS.
  • Morphological analysis and potentially lineage tracing techniques were employed to determine cell origins.

Main Results:

  • Evidence indicates that monocytes migrate from the periphery into the normal CNS.
  • These infiltrating monocytes undergo significant morphological transformations to differentiate into microglia.
  • This confirms that microglia are of monocytic origin.

Conclusions:

  • Microglia are derived from circulating monocytes.
  • Monocyte infiltration into the CNS presents a potential route for pathogen entry.
  • This 'Trojan horse' mechanism is implicated in the pathogenesis of CNS diseases caused by viruses and bacteria.

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