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Updated: May 21, 2026
10:36
Modeling Neuronal Death and Degeneration in Mouse Primary Cerebellar Granule Neurons
Published on: November 6, 2017
Generation of complement component C5a by ischemic neurons promotes neuronal apoptosis
Dale Pavlovski1, John Thundyil, Peter N Monk
1School of Biomedical Sciences, University of Queensland, Brisbane, Queensland, Australia.
Summary
Neurons can generate C5a, a molecule that triggers cell death in the central nervous system (CNS). Blocking the C5a receptor (CD88) protects against stroke-induced brain damage.
Area of Science:
- Neuroscience
- Immunology
- Molecular Biology
Background:
- C5a receptors (CD88) are present in the central nervous system (CNS) on neurons and glia.
- The source of C5a, the activator of these receptors, within the CNS remains largely unknown.
Purpose of the Study:
- To investigate the origin and role of C5a in CNS ischemic injury.
- To determine if neurons can produce C5a and if it contributes to neuronal apoptosis and stroke pathology.
Main Methods:
- Primary mouse cortical neurons were subjected to oxygen-glucose deprivation (OGD) to induce ischemia.
- C5a levels, CD88 expression, and apoptosis were measured.
- Studies utilized CD88(-/-) mice and a middle cerebral artery occlusion (MCAO) stroke model.
Main Results:
- Neurons constitutively express C5 (C5a precursor) and CD88.
- Ischemic stress (OGD) increased neuronal apoptosis, CD88 expression, and C5a release.
- Exogenous C5a induced apoptosis, while CD88 antagonism or deficiency protected neurons from ischemic injury and reduced stroke severity in vivo.
Conclusions:
- Neurons possess the intrinsic capacity to generate C5a upon ischemic stress.
- Neuronally derived C5a can activate neuronal CD88 receptors, exacerbating apoptosis.
- Targeting the C5a/CD88 pathway offers a potential therapeutic strategy for stroke.
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