Cellular and Molecular Neurobiology

, Volume 35, Issue 7, pp 961–975 | Cite as

Microglia in Glia–Neuron Co-cultures Exhibit Robust Phagocytic Activity Without Concomitant Inflammation or Cytotoxicity

  • Alexandra C. Adams
  • Michele Kyle
  • Carol M. Beaman-Hall
  • Edward A. MonacoIII
  • Matthew Cullen
  • Mary Lou VallanoEmail author
Original Research


A simple method to co-culture granule neurons and glia from a single brain region is described, and microglia activation profiles are assessed in response to naturally occurring neuronal apoptosis, excitotoxin-induced neuronal death, and lipopolysaccharide (LPS) addition. Using neonatal rat cerebellar cortex as a tissue source, glial proliferation is regulated by omission or addition of the mitotic inhibitor cytosine arabinoside (AraC). After 7–8 days in vitro, microglia in AraC cultures are abundant and activated based on their amoeboid morphology, expressions of ED1 and Iba1, and ability to phagocytose polystyrene beads and the majority of neurons undergoing spontaneous apoptosis. Microglia and phagocytic activities are sparse in AraC+ cultures. Following exposure to excitotoxic kainate concentrations, microglia in AraC cultures phagocytose most dead neurons within 24 h without exacerbating neuronal loss or mounting a strong or sustained inflammatory response. LPS addition induces a robust inflammatory response, based on microglial expressions of TNF-α, COX-2 and iNOS proteins, and mRNAs, whereas these markers are essentially undetectable in control cultures. Thus, the functional effector state of microglia is primed for phagocytosis but not inflammation or cytotoxicity even after kainate exposure that triggers death in the majority of neurons. This model should prove useful in studying the progressive activation states of microglia and factors that promote their conversion to inflammatory and cytotoxic phenotypes.


Microglia Co-cultures Phagocytosis Excitotoxicity Inflammation 


Conflict of interest

The authors, Alexandra C. Adams, Michele Kyle, Carol M. Beaman-Hall, Edward A. Monaco III, Matthew Cullen, Mary Lou Vallano, do not have any conflicts of interest to report.


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Alexandra C. Adams
    • 1
    • 3
  • Michele Kyle
    • 2
  • Carol M. Beaman-Hall
    • 1
  • Edward A. MonacoIII
    • 1
    • 4
  • Matthew Cullen
    • 1
    • 5
  • Mary Lou Vallano
    • 1
    Email author
  1. 1.Department of Neuroscience & PhysiologySUNY Upstate Medical UniversitySyracuseUSA
  2. 2.Department of NeurosurgerySUNY Upstate Medical UniversitySyracuseUSA
  3. 3.Department of Pulmonary and Critical CareMount Sinai Beth Israel Medical CenterNew YorkUSA
  4. 4.Department of Neurological SurgeryUniversity of Pittsburgh Medical CenterPittsburghUSA
  5. 5.Department of AnesthesiologyPhelps Memorial Hospital CenterSleepy HollowUSA

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