Related Experiment Video
Updated: May 13, 2026
Generating and Co-culturing Murine Primary Microglia and Cortical Neurons
Published on: July 26, 2024
Astrocytes inhibit microglial surface expression of dendritic cell-related co-stimulatory molecules through a
Giselles Acevedo1, Nischal K Padala, Li Ni
1Rutgers University/Newark, Newark, New Jersey, USA.
Abstract:
Murine microglia cultured in isolation were treated sequentially with granulocyte/monocyte colony-stimulating factor (GM-CSF) (5 days) and lipopolysaccharide (LPS) (2 days) to elicit a mature dendritic cell-like (DC-like) phenotype. Examined by flow cytometry microglia thus isolated show high surface expression of CD11c together with the co-stimulatory molecules CD40, CD80, and CD86 that are necessary for T-cell activation. In contrast, microglia co-cultured with astrocytes fail to achieve a mature DC-like phenotype. Contact with the astrocytic environment is necessary for the inhibition. Failure was not because of a more rapid degradation of protein. Bone marrow-derived cells, like microglia, were prevented by astrocytes from attaining a mature DC phenotype. Although GM-CSF pre-treatment substantially increases mRNA of co-stimulatory molecules and major histocompatibility complex (MHC) Class II in isolated microglia, co-cultured microglia await treatment with LPS to up-regulate them. In contrast, western blot and immunocytochemical analysis revealed that it is not a failure of transcription or translation, nor is it a more rapid degradation of mRNA that is responsible for the low surface expression; rather microglia co-cultured with astrocytes produce mRNA and protein but do not traffic the protein onto the cell surface.
Insights
Astrocytes inhibit microglia from becoming mature dendritic cells (DCs). Astrocytes prevent the surface expression of necessary molecules by retaining proteins within the cell, not by affecting their production or degradation.
Area of Science:
- Neuroimmunology
- Cell Biology
- Immunology
Background:
- Microglia, the resident immune cells of the central nervous system, share similarities with myeloid cells.
- Dendritic cells (DCs) are crucial for initiating adaptive immune responses.
- Understanding microglia's potential to adopt DC-like phenotypes is key to neuroinflammation research.
Purpose of the Study:
- To investigate whether murine microglia can acquire a mature dendritic cell-like (DC-like) phenotype.
- To determine the role of astrocytes in modulating microglial maturation towards a DC-like phenotype.
Main Methods:
- Murine microglia were cultured in isolation or co-cultured with astrocytes.
- Cells were treated with granulocyte/monocyte colony-stimulating factor (GM-CSF) and lipopolysaccharide (LPS).
- Flow cytometry, western blot, and immunocytochemistry were used to analyze cell surface marker expression and protein trafficking.
Main Results:
- Isolated microglia treated with GM-CSF and LPS exhibited a mature DC-like phenotype with high expression of CD11c, CD40, CD80, and CD86.
- Microglia co-cultured with astrocytes failed to achieve this mature DC-like phenotype.
- Astrocytes did not cause faster protein degradation or inhibit transcription/translation; instead, they prevented the surface trafficking of proteins in microglia.
Conclusions:
- Astrocytes actively inhibit the maturation of microglia into DC-like cells.
- The astrocytic influence on microglia involves impaired protein surface transport, not reduced synthesis or increased degradation.
- This finding highlights the critical role of the microenvironment in regulating microglial immune functions.
Related Concept Videos
01:31Nervous Tissue: Glial Cells
The CNS glial cell includes the astrocytes, the oligodendrocytes, the microglia, and the ependymal cells.
Astrocytes are star-shaped glial cells that interact...
01:04Glial Cells