Different Cell Types in the CNS One Flashcards
What are the glial cells in the brain?
Microglia Oligodendrocytes Satellite cells Ependymall cells Schwann cells (PNS) Astrocytes
What are other cells in the brain apart from glia and neurons?
Pericytes
Endothelial Cells
Fibroblast like cells
T cells (Very scarce)
What are the most abundant cells in the brain?
Glial cells
What is the role of microglial?
They are professional phagocytes - They have the largest variety of things they phagocytose
(Location = more specific function)
What is the origin of microglia?
They are of myeloid/ monolytic origin (Like RBC…)
Microglia are essentially:
Immune cells of the brain ( as are astrocytes and endothelial cells)
Are all microglia the same?
There are different FUNCTIONAL subsets of microglia (express different markers and have different morphology)
As professional phagocytes what do microglia respond to?
Cytokines during inflammation to increase their phagocytic activity i.e In alzhiemers
During injury other that phagocytose what else may microglia do?
During injury microglia may secrete proinflammatory cytokines and present antigens to other immune cells (APC)
Are microglia static?
Microglia are dynamic and can move locations therefore can change function
How are microglia subsets classified?
Morphology (bad)
Very few immunological names
Functional makers (common and good)
Why is microglia classification using appearance bad?
Appearance is subjective
What sort of immunological markers could be used to classify microglia?
Chemokine receptors (CCR)
HLA markers
MHC’s (major histocompatibility complexes)
Cytokine production
Why would immunological markers be a good way to classify microglia?
As they elude to cellular function
What are three reasons why microglia would make good therapeutic targets?
1) Enhanced phagocytosis for debris clearance
2) Enhanced inflammation (cytokine / chemokine strategies)
3) Suppression of APC (MS/Stroke/Autoimmunity)
What are two problems with targeting microglia for therapeutic reasons?
1) Microglia are functionally diverse (APC vs Phagocytosis) therefore target specificity (indistinguishable atm)
2) Crossing BBB
What is the major function of astrocytes?
CNS health
What are some functions of astrocytes?
Support neurons by:
Neurotransmitter supplies / clearance (glutamate excitotoxicity)
Waste removal
Nutrient supply
Maintenance support of neurovascular unit
May have progenitor qualities
Supply neutrotrophic factors
Describe astrocyte structure
Astrocyte foot processes extend around blood vessels and neurons
What do neutrotrophic factors do?
Growth factor and for survivial
List three supporting roles astrocytes have
Neurovascular support
Neuron support
Immunological support
What is the role of astrocytes during inflammation?
They have a immunological function
Resident brain innate immune cells
During injury what do astrocytes do?
Migrate towards the site of injury
Produce and respond to cytokines/chemokines/ neutrotrophic factors
What are some examples of chemokines that astrocytes produce?
IP10
IL8
MIP1
MCP1
What are the functions of chemokines?
Attract other immune cells to the site of damage (chemoattractants)
During inflammation what do neutrotrophic factors do?
Prevent neuronal death
Whats an effective staining method for astrocytes?
They are GFAP postive so staining this will make astrocytes stand out distinctively
