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Updated: Aug 7, 2026
11:29
Isolation of Soluble and Insoluble PrP Oligomers in the Normal Human Brain
Published on: October 3, 2012
Human prions and plasma lipoproteins
Jiri G Safar1, Holger Wille, Michael D Geschwind
1Institute for Neurodegenerative Diseases, Department of Neurology, University of California, San Francisco, CA 94143, USA.
Summary
Prions, infectious proteins causing Creutzfeldt-Jakob disease (CJD), bind to specific blood lipoproteins (VLDL and LDL). This discovery may lead to new prion detection methods in blood.
Area of Science:
- Neuroscience
- Biochemistry
- Molecular Biology
Background:
- Prions are misfolded proteins (PrPSc) responsible for neurodegenerative diseases.
- PrPSc is difficult to solubilize, hindering detection.
- Lipoproteins share properties with PrPSc, suggesting a potential interaction.
Purpose of the Study:
- To investigate the binding of prions (PrPSc) to lipoproteins in blood.
- To determine if prions interact with very low-density (VLDL), low-density (LDL), or high-density (HDL) lipoproteins.
Main Methods:
- Affinity assays and electron microscopy were used to detect prion-lipoprotein binding.
- Immunoassays quantified the interaction between apolipoprotein B (apoB) and PrPSc.
- Prion binding to LDL was assessed after denaturation using guanidine hydrochloride.
Main Results:
- Prions (PrPSc) from Creutzfeldt-Jakob disease (CJD) brains selectively bind to VLDL and LDL, not HDL.
- Apolipoprotein B (apoB), a component of VLDL and LDL, mediates PrPSc binding.
- Binding constants for PrPSc and apoB/LDL ranged from 28 to 212 pM.
Conclusions:
- Prions in the blood may be associated with VLDL and LDL lipoproteins.
- This interaction could offer a novel target for developing antemortem diagnostic tests for prion diseases.
- Further research is needed to validate PrPSc detection in lipoproteins for clinical and veterinary diagnostics.
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