Related Experiment Video
Updated: Aug 18, 2026
Isolation of Cortical Microglia with Preserved Immunophenotype and Functionality From Murine Neonates
Published on: January 30, 2014
Microglia overexpressing the macrophage colony-stimulating factor receptor are neuroprotective in a
Olivera M Mitrasinovic1, Alicia Grattan, Christopher C Robinson
1Neuroscience Research Laboratories, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California 94305, USA.
Abstract:
Microglia with increased expression of the macrophage colony-stimulating factor receptor (M-CSFR; c-fms) are found surrounding plaques in Alzheimer's disease (AD) and in mouse models for AD and after ischemic or traumatic brain injury. Increased expression of M-CSFR causes microglia to adopt an activated state that results in proliferation, release of cytokines, and enhanced phagocytosis. To determine whether M-CSFR-induced microglial activation affects neuronal survival, we assembled a coculture system consisting of BV-2 microglia transfected to overexpress the M-CSFR and hippocampal organotypic slices treated with NMDA. Twenty-four hours after assembly of the coculture, microglia overexpressing M-CSFR proliferated at a higher rate than nontransfected control cells and exhibited enhanced migration toward NMDA-injured hippocampal cultures. Surprisingly, coculture with c-fms-transfected microglia resulted in a dramatic reduction in NMDA-induced neurotoxicity. Similar results were observed when cocultures were treated with the teratogen cyclophosphamide. Biolistic overexpression of M-CSFR on microglia endogenous to the organotypic culture also rescued neurons from excitotoxicity. Furthermore, c-fms-transfected microglia increased neuronal expression of macrophage colony-stimulating factor (M-CSF), the M-CSFR, and neurotrophin receptors in the NMDA-treated slices, as determined with laser capture microdissection. In the coculture system, direct contact between the exogenous microglia and the slice was necessary for neuroprotection. Finally, blocking expression of the M-CSF ligand by exogenous c-fms-transfected microglia with a hammerhead ribozyme compromised their neuroprotective properties. These results demonstrate a protective role for microglia overexpressing M-CSFR in our coculture system and suggest under certain circumstances, activated microglia can help rather than harm neurons subjected to excitotoxic and teratogen-induced injury.
Insights
Microglia overexpressing the macrophage colony-stimulating factor receptor (M-CSFR) protect neurons from injury. This M-CSFR-induced microglial activation surprisingly reduces neurotoxicity in experimental models.
Area of Science:
- Neuroscience
- Immunology
- Cell Biology
Background:
- Microglia, the brain's immune cells, show increased macrophage colony-stimulating factor receptor (M-CSFR) expression around plaques in Alzheimer's disease and after brain injuries.
- Elevated M-CSFR expression activates microglia, leading to proliferation, cytokine release, and enhanced phagocytosis.
Purpose of the Study:
- To investigate the role of M-CSFR-induced microglial activation in neuronal survival.
- To determine if M-CSFR-expressing microglia impact neurotoxicity in experimental models.
Main Methods:
- A coculture system was established using BV-2 microglia overexpressing M-CSFR and hippocampal organotypic slices exposed to NMDA.
- Neurotoxicity was assessed after NMDA or cyclophosphamide treatment in cocultures with M-CSFR-overexpressing microglia.
- Laser capture microdissection was used to analyze gene expression in neurons.
Main Results:
- Microglia overexpressing M-CSFR showed increased proliferation and migration toward injured neurons.
- Coculture with M-CSFR-overexpressing microglia significantly reduced NMDA-induced neurotoxicity and protected neurons from cyclophosphamide.
- Direct contact between microglia and slices was essential for neuroprotection, and blocking M-CSF ligand impaired this effect.
Conclusions:
- Microglia overexpressing M-CSFR exhibit neuroprotective properties in experimental models of excitotoxicity and teratogen-induced injury.
- These findings suggest that under specific conditions, activated microglia can safeguard neurons rather than contribute to harm.
