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Updated: Aug 21, 2026
Modeling Stroke in Mice - Middle Cerebral Artery Occlusion with the Filament Model
Published on: January 6, 2011
A role for interferon-gamma in focal cerebral ischemia in mice
Kate Lykke Lambertsen1, Rikke Gregersen, Michael Meldgaard
1Department of Anatomy and Neurobiology, University of Southern Denmark, Winsloewparken 21, DK-5000 Odense C, Denmark. klambertsen@health.sdu.dk
Abstract:
The pro-inflammatory cytokine interferon-gamma (IFNgamma) has traditionally been associated with inflammatory CNS disease and more recently with ischemia-induced pathology. Using a murine model of focal cerebral ischemia, we found no evidence for induction of IFNgamma mRNA after permanent middle cerebral artery occlusion. In addition, we found that mice deficient in IFNgamma or IFNgamma receptors developed neocortical infarcts similar in size to those in wild type. In contrast, MBP promoter-IFNgamma-transgenic mice consistently developed significantly larger infarcts than non-transgenic mice. Because IFNgamma is a potent activator of microglia-macrophages, we investigated the involvement of microglial-macrophage-derived TNF in the larger infarcts. Numbers of TNF mRNA-expressing microglia-macrophages and levels of TNF mRNA and TNF in IFNgamma-transgenic and non-transgenic mice were similar. Furthermore, the ischemic brain damage in IFN-gamma-transgenic mice was unaffected by recombinant soluble TNF receptor I. Taken together, the data argues against a role for IFNgamma in cerebral ischemia under normal conditions. However, when present, IFNgamma significantly exacerbates ischemia-induced brain damage by mechanisms that appear to be independent of TNF or synergistic neurotoxic interactions of IFNgamma and TNF Irrespective of the mechanism(s) involved, this enhancing effect of IFNgamma on ischemia-induced neurotoxicity may need to be considered in diseases where immune IFNgamma is involved, such as multiple sclerosis.
Insights
Interferon-gamma (IFNgamma) does not cause brain damage after stroke in normal conditions. However, elevated IFNgamma levels significantly worsen stroke-related brain injury through unknown mechanisms.
Area of Science:
- Neuroscience
- Immunology
- Pathology
Background:
- The pro-inflammatory cytokine interferon-gamma (IFNgamma) is linked to central nervous system (CNS) inflammation and ischemia.
- Its role in cerebral ischemia, particularly stroke, requires further elucidation.
Purpose of the Study:
- To investigate the role of IFNgamma in the pathogenesis of focal cerebral ischemia.
- To determine if IFNgamma exacerbates ischemic brain damage and elucidate potential mechanisms involving TNF.
Main Methods:
- Utilized a murine model of permanent focal cerebral ischemia (middle cerebral artery occlusion).
- Compared infarct volumes in wild-type, IFNgamma-deficient, IFNgamma receptor-deficient, and IFNgamma-transgenic mice.
- Assessed TNF mRNA and protein levels in microglia-macrophages and evaluated the effect of TNF inhibition.
Main Results:
- No induction of IFNgamma mRNA was observed post-ischemia in wild-type mice.
- IFNgamma-deficient and receptor-deficient mice showed infarct sizes comparable to wild-type mice.
- IFNgamma-transgenic mice exhibited significantly larger infarcts, independent of TNF pathways.
Conclusions:
- IFNgamma does not play a significant role in the acute phase of cerebral ischemia under normal physiological conditions.
- Exogenous or elevated IFNgamma exacerbates ischemia-induced brain damage via TNF-independent mechanisms.
- The findings suggest a potential role for IFNgamma in exacerbating neurotoxicity in conditions like multiple sclerosis, where it is present.
