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Investigating the Spreading and Toxicity of Prion-like Proteins Using the Metazoan Model Organism C. elegans
12:57

Investigating the Spreading and Toxicity of Prion-like Proteins Using the Metazoan Model Organism C. elegans

Published on: January 8, 2015

Lymphoid signal transduction mechanisms linked to cellular prion protein

I E Mazzoni1, H C Ledebur, E Paramithiotis

  • 1Caprion Pharmaceuticals, Montreal, QC H4S 2C8, Canada.

Biochemistry and Cell Biology = Biochimie Et Biologie Cellulaire
|October 20, 2005
PubMed

Insights

The prion protein (PrPC) plays a role in immune function. Mice lacking PrPC show reduced splenocyte proliferation and altered protein signaling pathways, indicating its importance in immune responses.

Area of Science:

  • Immunology
  • Cell Biology
  • Neuroscience

Background:

  • The cellular prion protein (PrPC) is a cell surface protein found in various cells, including lymphoid cells.
  • Its precise function, particularly in immune responses, remains incompletely understood.

Purpose of the Study:

  • To investigate the role of PrPC in immune cell activation and signaling.
  • To compare lectin-induced mitogenesis and cell signaling pathways in splenocytes from wild-type and PrPC-deficient mice.

Main Methods:

  • Splenocytes from wild-type and Prnp0/0 mice were stimulated with lectins (Concanavalin A and phytohemagglutinin).
  • Proliferation was assessed by 3H-thymidine incorporation.
  • Protein phosphorylation patterns (PKC, MAPK) and calcium fluxes were analyzed.

Main Results:

  • Prnp0/0 splenocytes exhibited significantly reduced proliferation, especially early in activation.
  • Defects in the phosphorylation of Protein Kinase C (PKC) alpha/beta and p44/42 MAPK were observed in Concanavalin A-activated Prnp0/0 splenocytes.
  • Calcium fluxes were comparable between wild-type and Prnp0/0 splenocytes, suggesting they are not directly involved in the observed signaling defects.

Conclusions:

  • The absence of PrPC impairs splenocyte activation and proliferation.
  • PrPC appears to modulate PKCalpha/beta phosphorylation, impacting its role in regulating splenocyte mitosis.
  • These findings support a role for PrPC in modulating immune function.

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