Article

Temporal and spatial relationship between the death of PrP-damaged neurones and microglial activation.

Institute of Comparative Medicine, Department of Veterinary Pathology, Univeristy of Glasgow Veterinary School, Bearsden Road, Glasgow G61 IQH, UK.
Neuroreport (impact factor: 1.66). 10/2002; 13(13):1695-700. pp.1695-700
Source: PubMed

ABSTRACT Previous studies have demonstrated a role for microglia in the neuronal loss that occurs in the transmissible spongiform encephalopathies or prion diseases. In the present studies, the processes that lead to the death of neurones treated with synthetic peptides derived from the prion protein (PrP) were fully activated within 1 h, although neuronal cell death was not seen until 24 h later. Similarly, neurones exposed to PrP peptides for only 1 h activated microglia and a temporal relationship between the production of interleukin-6, an indicator of microglial activation, and microglial killing of PrP-treated neurones was also demonstrated. Activation of microglia and microglia-mediated killing of PrP-treated neurones or scrapie-infected neuroblastoma cells were maximal only when microglia were in direct contact with neurones.

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Keywords

1 h activated microglia
 
direct contact
 
microglia-mediated
 
microglial
 
microglial activation
 
neuronal cell death
 
neuronal loss
 
neurones
 
present studies
 
Previous studies
 
PrP
 
PrP peptides
 
PrP-treated neurones
 
scrapie-infected neuroblastoma cells
 
synthetic peptides
 
temporal relationship
 
transmissible spongiform encephalopathies