Related Experiment Video

Updated: Jun 10, 2026

Photothrombotic Ischemia: A Minimally Invasive and Reproducible Photochemical Cortical Lesion Model for Mouse Stroke Studies
08:40

Photothrombotic Ischemia: A Minimally Invasive and Reproducible Photochemical Cortical Lesion Model for Mouse Stroke Studies

Published on: June 9, 2013

Characterization of the inflammatory response in a photothrombotic stroke model by MRI: implications for stem cell

Caroline Vandeputte1, Debby Thomas, Tom Dresselaers

  • 1Division of Nuclear Medicine, Katholieke Universiteit Leuven, Leuven, Belgium.

Molecular Imaging and Biology
|August 12, 2010
PubMed
Abstract

Insights

Magnetic resonance imaging (MRI) contrast in photothrombotic (PT) stroke models can be misleading. Histology is essential to differentiate SPIO-labeled stem cells from inflammatory cells in PT stroke models.

Area of Science:

  • Neuroscience
  • Biomedical Imaging
  • Regenerative Medicine

Background:

  • Photothrombotic (PT) stroke models are used to study stroke pathophysiology.
  • Superparamagnetic iron oxide (SPIO)-labeled stem cells are investigated for cell tracking in vivo.
  • Magnetic resonance imaging (MRI) is a key tool for non-invasive monitoring of cell therapies.

Purpose of the Study:

  • To evaluate the specificity of MRI contrast in a PT stroke model.
  • To assess MRI contrast with and without SPIO-labeled stem cell engraftment.
  • To determine if MRI can reliably distinguish SPIO-labeled cells from endogenous cells.

Main Methods:

  • Animals underwent PT stroke induction.
  • T(2)/T(2)*-weighted MRI was performed at multiple time points post-induction.
  • Animals were either engrafted with SPIO-labeled stem cells or not.
  • MRI results were correlated with immunohistochemistry.

Main Results:

  • T(2)*-weighted MRI showed hypointense contrast in the lesion border zone.
  • This hypointensity was attributed to inflammatory cell accumulation and iron deposition.
  • Similar signal changes were observed with SPIO-labeled cells, complicating interpretation.
  • Histological analysis was crucial for differentiating SPIO-labeled cells from immune cells.

Conclusions:

  • MRI contrast in PT stroke models with stem cell engraftment can be confounded by inflammation.
  • Non-invasive monitoring of SPIO-labeled stem cells using MRI requires careful interpretation in inflammatory settings.
  • Histological validation is indispensable for accurate assessment of cell engraftment and distribution.

More Related Videos

Modeling Stroke in Mice: Focal Cortical Lesions by Photothrombosis06:07

Modeling Stroke in Mice: Focal Cortical Lesions by Photothrombosis

Published on: May 6, 2021

Related Concept Videos

Ischemic Stroke ll: Pathophysiology01:15

Ischemic Stroke ll: Pathophysiology

An ischemic stroke occurs when a cerebral blood vessel becomes obstructed, most often by a thrombus or embolus, interrupting the delivery of oxygen and glucose to brain tissue. Because neurons rely on continuous aerobic metabolism, energy failure begins within minutes of reduced perfusion. The region receiving the least blood flow becomes the infarct core, an area of irreversible cellular death. Surrounding this core lies the penumbra, a zone of hypoperfused but still viable tissue that is...