Do bovine lymphocytes express a peculiar prion protein?

Area of Science:

• Immunology
• Neuroscience
• Biochemistry

Background:

• Cellular prion protein (PrPc) is a cell surface protein involved in transmissible spongiform encephalopathies (TSEs).
• Bovine spongiform encephalopathy (BSE) infectivity is mainly in the central nervous system, unlike scrapie or variant CJD.
• PrPc expression is essential for prion replication.

Purpose of the Study:

• Investigate PrPc expression in bovine immune cells.
• Assess intra- and interindividual variability of PrPc expression.
• Explore the role of PrPc glycosylation in bovine immune cell infectivity.

Main Methods:

• Isolation of lymphocytes from blood and lymph organs of six individual cattle.
• Flow cytometry to quantify PrPc expression on different immune cell types.
• Western blotting to analyze PrPc glycosylation states.

Main Results:

• PrPc expression is absent or weak on granulocytes but present on monocytes, B, and T cells.
• Bovine immune cell activation leads to increased PrPc expression.
• Western blotting revealed only the diglycosylated form of PrPc.

Conclusions:

• Bovine immune cells, particularly monocytes, B, and T cells, express PrPc.
• PrPc expression is upregulated upon immune cell activation.
• The exclusive diglycosylation of PrPc in bovine immune cells may explain the absence of infectivity.