Concentration and removal of prion proteins from biological solutions

• Published in: Biotechnology and applied biochemistry 2003-04, Vol.37 (2), p.173-182
• Main Authors: Zeiler, Brian, Adler, Victor, Kryukov, Valentin, Grossman, Abraham
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Biotechnology; bovine spongiform encephalopathy (BSE); Chromatography, Affinity - methods; filtration; Fundamental and applied biological sciences. Psychology; Health. Pharmaceutical industry; Industrial applications and implications. Economical aspects; Membranes, Artificial; Miscellaneous; prion protein (PrP); Protein Binding; PrPC Proteins - blood; PrPC Proteins - chemistry; PrPC Proteins - isolation & purification; PrPC Proteins - urine; RNA; RNA - chemical synthesis; RNA - chemistry; RNA-protein interaction; Ultrafiltration - methods
• ISSN: 0885-4513; 1470-8744
• DOI: 10.1042/BA20020087

The pathogenesis of prion diseases is characterized by the accumulation of amyloid‐like rods or scrapie‐associated fibrils. The major protein component of scrapie‐associated fibrils is an abnormally folded isoform of the normal cellular prion protein (PrPC) that is resistant to digestion by proteinase K and is referred to as PrPSc. Purified human recombinant (hr PrP) was used to characterize the binding of a set of RNAs with affinity to PrP proteins. We report here that hr PrP has two RNA‐binding activities at physiological pH. One activity is capable of binding all of the screened RNAs with high affinity, whereas the other activity can bind only to a subset of the RNAs with high affinity in the presence of non‐specific competitor RNAs. A novel RNA belonging to the latter class, RQ11+12, bound to hr PrP with high affinity in the presence of vast molar excesses of competing RNAs. Beads impregnated with the RQ11+12 RNA were used to construct a filtration column. The column efficiently bound hr PrP and native PrPC from serum and urine. Importantly, the filtration device was also capable of binding proteinase K‐treated PrPSc from serum and urine. The level of sensitivity of detection of PrP by standard Western blotting was increased at least 1000‐fold by first concentrating PrP from solution with the filtration column.