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Assessing Transmissible Spongiform Encephalopathy Species Barriers with an In Vitro Prion Protein Conversion Assay
Published on: March 10, 2015
Cellular prion protein in ovine milk
Ben C Maddison1, Garry C Whitelam, Kevin C Gough
1ADAS UK, Department of Biology, University of Leicester, University Road, Leicester, LE1 7RH, UK.
Biochemical and Biophysical Research Communications
|December 19, 2006
Summary
Cellular prion protein (PrP(C)) was found in ovine milk, differing from brain PrP(C) in mobility and glycosylation. This soluble PrP(C) also appears in bovine milk, with fragments in commercial products.
Area of Science:
- Veterinary Medicine
- Neuroscience
- Biochemistry
Background:
- Cellular prion protein (PrP(C)) is crucial for prion diseases and found in sheep's neuronal and non-neuronal tissues.
- Mammary gland tissue in sheep contains lower concentrations of PrP(C).
Purpose of the Study:
- To investigate the presence and characteristics of soluble cellular prion protein (PrP(C)) in ovine milk.
- To compare ovine milk PrP(C) with brain-derived PrP(C) and analyze its molecular forms.
Main Methods:
- Clarification and fractionation of ovine milk to isolate the non-cellular, non-lipid fraction.
- Electrophoretic analysis to assess PrP(C) mobility and glycosylation patterns.
- Comparison with PrP(C) from ovine brain and bovine milk samples.
Main Results:
- Soluble PrP(C) was detected in the clarified, non-cellular, non-lipid fraction of ovine milk.
- Ovine milk PrP(C) exhibited increased electrophoretic mobility compared to brain-derived PrP(C).
- Ovine milk PrP(C) primarily existed as three species based on N-linked glycosylation, with inter-animal variability; similar forms were found in bovine milk.
Conclusions:
- Soluble PrP(C) is present in ovine milk, presenting distinct electrophoretic and glycosylation characteristics compared to brain PrP(C).
- The presence of PrP(C) in milk, including bovine milk and commercial products, suggests potential implications for prion disease research and transmission studies.
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