Related Experiment Video

Updated: May 26, 2026

Quantitative 3D In Silico Modeling (q3DISM) of Cerebral Amyloid-beta Phagocytosis in Rodent Models of Alzheimer's Disease
09:33

Quantitative 3D In Silico Modeling (q3DISM) of Cerebral Amyloid-beta Phagocytosis in Rodent Models of Alzheimer's Disease

Published on: December 26, 2016

Increased circulating TREM2+ microglial extracellular vesicles in aged APP/PS1 Alzheimer's disease rats

Sarah J Myers1, Manoj Reddy Medapati1, Brian L Allman1

  • 1Vulnerable Brain Lab, Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada.

Brain, Behavior, & Immunity - Health
|May 25, 2026
PubMed

Insights

Researchers identified TREM2-expressing microglial extracellular vesicles (EVs) in rat plasma. Increased levels of these EVs correlated with cognitive decline in an Alzheimer

Area of Science:

  • Neuroscience
  • Biomarkers
  • Alzheimer's Disease Research

Background:

  • TREM2 is a key microglial marker implicated in Alzheimer's disease (AD) pathogenesis.
  • Detecting TREM2 expression *in vivo* is challenging, limiting understanding of its role.
  • Extracellular vesicles (EVs), particularly microglial EVs (MEVs), are emerging as promising biomarkers.

Purpose of the Study:

  • To investigate plasma-derived TREM2+ MEVs as peripheral indicators of brain microglial TREM2 activity.
  • To assess the relationship between TREM2+ MEVs and cognitive function in a rat model of aging and AD.
  • To establish TMEM119+/TREM2+ EVs as a potential peripheral biomarker for AD-related microglial changes.

Main Methods:

  • Fluorescent labeling and nanoscale flow cytometry of TMEM119+/TREM2+ EVs in rat plasma.
  • Analysis of plasma from wildtype and APP/PS1 rats at 3, 9, and 15 months of age.
  • Assessment of brain microglial markers, TREM2 expression, and spatial memory using radial arm water maze.

Main Results:

  • TMEM119+/TREM2+ EVs were successfully detected in systemic circulation.
  • Elevated levels of TMEM119+/TREM2+ EVs were observed in aged APP/PS1 rats (15 months).
  • A modest association was found between TMEM119+/TREM2+ EV levels and cognitive impairment severity.

Conclusions:

  • Plasma-derived TMEM119+/TREM2+ EVs can serve as a peripheral indicator of brain microglial activity.
  • These EVs show potential as a non-invasive biomarker for cognitive impairment in aging and AD.
  • This study provides a novel method for assessing microglial function peripherally in AD models.
Keywords:
AgingAlzheimer's diseaseCognitionExtracellular vesicleMicrogliaTREM2

More Related Videos

Correlative Light and Electron Microscopy to Study Microglial Interactions with β-Amyloid Plaques10:52

Correlative Light and Electron Microscopy to Study Microglial Interactions with β-Amyloid Plaques

Published on: June 1, 2016

Preparation of Acute Hippocampal Slices from Rats and Transgenic Mice for the Study of Synaptic Alterations during Aging and Amyloid Pathology14:57

Preparation of Acute Hippocampal Slices from Rats and Transgenic Mice for the Study of Synaptic Alterations during Aging and Amyloid Pathology

Published on: March 23, 2011

Related Concept Videos

Alzheimer Disease ll: Pathophysiology01:23

Alzheimer Disease ll: Pathophysiology

Alzheimer disease involves structural changes in the brain that begin long before symptoms appear. The most distinctive features are extracellular neuritic plaques and intracellular neurofibrillary tangles.Neuritic plaques form in the cerebral cortex and around blood vessels. These plaques contain a dense core of beta-amyloid (Aβ)—a toxic protein fragment that clumps outside neurons. The core is surrounded by damaged neuronal extensions, as well as reactive astrocytes and microglia. Abnormal...