Related Experiment Video
Updated: Dec 7, 2025
Isolation and Flow Cytometric Analysis of Immune Cells from the Ischemic Mouse Brain
Published on: February 12, 2016
The role of peripheral monocytes and macrophages in ischemic stroke
Abstract:
After acute ischemic stroke (AIS), peripheral monocytes infiltrate into the lesion site within 24 h, peak at 3 to 7 days, and then differentiate into macrophages. Traditionally, monocytes/macrophages (MMs) are thought to play a deleterious role in AIS. Depletion of MMs in the acute phase can alleviate brain injury induced by ischemia. However, several studies have shown that MMs have anti-inflammatory functions, participate in angiogenesis, phagocytose necrotic neurons, and promote neurovascular repair. Therefore, MMs play dual roles in ischemic stroke, depending mainly upon the MM microenvironment and the window of time post-stroke. Because activated microglia and MMs are similar in morphology and function, previous studies have often investigated them together. However, recent studies have used special methods to distinguish MMs from microglia and have found that MMs have properties which differ from microglia. Here, we review the unique role of MMs and the interaction between MMs and neurovascular units, including neurons, astrocytes, microglia, and microvessels. Future therapeutics targeting MMs should regulate the polarization and subset transformation of the MMs at different stages of AIS rather than comprehensively suppressing MM infiltration and differentiation. In addition, more studies are needed to elucidate the cellular and molecular mechanisms of MM subsets and polarization during ischemic stroke.
Insights
Monocytes/macrophages (MMs) play dual roles in acute ischemic stroke (AIS), exhibiting both damaging and repairing functions. Future therapies should target MM polarization and subsets during AIS, not just infiltration.
Area of Science:
- Neuroscience
- Immunology
- Pathology
Background:
- Peripheral monocytes infiltrate brain lesions within 24 hours after acute ischemic stroke (AIS), peaking between 3-7 days.
- Traditionally, monocytes/macrophages (MMs) were considered detrimental in AIS, with their depletion alleviating brain injury.
- Emerging evidence suggests MMs also possess anti-inflammatory properties, promote angiogenesis, clear debris, and aid neurovascular repair.
Purpose of the Study:
- To review the unique roles of monocytes/macrophages (MMs) in acute ischemic stroke (AIS).
- To examine the interaction between MMs and neurovascular units (neurons, astrocytes, microglia, microvessels).
- To discuss future therapeutic strategies targeting MMs in AIS.
Main Methods:
- Literature review of studies investigating monocytes/macrophages in acute ischemic stroke.
- Analysis of recent research distinguishing monocytes/macrophages from microglia.
- Synthesis of findings on MM interaction with neurovascular components.
Main Results:
- MMs exhibit dual roles in AIS, influenced by microenvironment and stroke timing.
- MMs possess distinct properties from microglia, necessitating specific investigation.
- MMs interact dynamically with neurons, astrocytes, microglia, and microvessels.
Conclusions:
- Future AIS therapeutics should focus on modulating MM polarization and subset transformation rather than broad suppression.
- Further research is required to fully elucidate the mechanisms of MM subsets and polarization in ischemic stroke.
- Understanding the nuanced roles of MMs is crucial for developing effective AIS treatments.
More Related Videos
08:22Isolation and Flow Cytometric Assessment of Neuroimmune Interactions in a Mini-Stroke Murine Model
Published on: June 20, 2025
12:42Stereological and Flow Cytometry Characterization of Leukocyte Subpopulations in Models of Transient or Permanent Cerebral Ischemia
Published on: December 28, 2014
Related Concept Videos
01:38Inflammation
01:17Ischemic Heart Disease: Overview
Atherosclerosis, the primary malefactor, orchestrates this dangerous condition. It manifests as the accumulation of fatty deposits, akin to insidious plaques, within arterial walls. As time elapses, these plaques metamorphose, hardening and...