Interleukin-1beta and tumor necrosis factor-alpha are expressed by different subsets of microglia and macrophages after ischemic stroke in mice

Bettina H Clausen, Kate L Lambertsen, Alicia A Babcock, Thomas H Holm, Frederik Dagnaes-Hansen, Bente Finsen

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

BACKGROUND: Interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) are expressed by microglia and infiltrating macrophages following ischemic stroke. Whereas IL-1beta is primarily neurotoxic in ischemic stroke, TNF-alpha may have neurotoxic and/or neuroprotective effects. We investigated whether IL-1beta and TNF-alpha are synthesized by overlapping or segregated populations of cells after ischemic stroke in mice. METHODS: We used flow cytometry and immunohistochemistry to examine cellular co-expression of IL-1beta and TNF-alpha at 6, 12 and 24 hours after permanent middle cerebral artery occlusion in mice, validating the results by the use of bone marrow chimeric mice. RESULTS: We found that IL-1beta and TNF-alpha were expressed in largely segregated populations of CD11b+CD45dim microglia and CD11b+CD45high macrophages, with cells expressing both cytokines only rarely. The number of Gr1+ granulocytes producing IL-1beta or TNF-alpha was very low, and we observed no IL-1beta- or TNF-alpha-expressing T cells or astrocytes. CONCLUSION: Taken together, the results show that IL-1beta and TNF-alpha are produced by largely segregated populations of microglia and macrophages after ischemic stroke in mice. Our findings provide evidence of a functional diversity among different subsets of microglia and macrophages that is potentially relevant to future design of anti-inflammatory therapies in stroke.
Original languageEnglish
JournalJournal of Neuroinflammation
Volume5
Pages (from-to)46
ISSN1742-2094
DOIs
Publication statusPublished - 1. Jan 2008

Keywords

  • Animals
  • Antigens, CD11
  • Antigens, CD45
  • Brain Ischemia
  • Cell Lineage
  • Cells, Cultured
  • Disease Models, Animal
  • Encephalitis
  • Flow Cytometry
  • Immunohistochemistry
  • Infarction, Middle Cerebral Artery
  • Interleukin-1beta
  • Macrophages
  • Male
  • Mice
  • Mice, Transgenic
  • Microglia
  • Stroke
  • Transplantation Chimera
  • Tumor Necrosis Factor-alpha

Fingerprint Dive into the research topics of 'Interleukin-1beta and tumor necrosis factor-alpha are expressed by different subsets of microglia and macrophages after ischemic stroke in mice'. Together they form a unique fingerprint.

Cite this