NR AWCF
AU Birkmann,E.; Henke,F.; Willbold,D.; Riesner,D.
TI Surface-FIDA: a new diagnostic tool for prion diseases
QU International Conference - Prion 2006: Strategies, advances and trends towards protection of society - 3.10.-6.10.2006, Torino, Italy, Lingotto Conference Centre - Oral sessions ORAL-45
PT Konferenz-Vortrag
AB The infectious agents of prion diseases are composed primarily of the pathogenic isoform of the prion protein designated PrPsc, which is generated by a conformational change of the cellular isoform PrPc. In contrast to its cellular isoform, the pathogenic isoform PrPsc forms insoluble aggregates. Hitherto accredited prion tests use the PK-resistance of PrPsc as a marker for the disease. Because of varying portions of disease related aggregated PrP, which is not PK-resistant (1,2), these prion tests offer only a limited sensitivity. Therefore prion detection, which does not rely on PK-digestion, would be favourable for a sensitive diagnosis. It would allow the detection of both, PK-resistant and PKsensitive PrPsc. Our new test system is based on Dual-Colour Fluorescence-Intensity-DistributionAnalysis (2D-FIDA). It is able to detect and quantify protein aggregates and to distinguish the aggregated from the monomeric or oligomeric state, irrespective of PK-resistance. To increase the sensitivity, PrPsc was concentrated by immobilizing the particles at the surface of a slide. Consequently the immobilisation reduces the dispersion of the prions from three dimensions in solution to two dimensions on a surface. The surface can be scanned systematically and single prion particles are counted (Surface-FIDA). With Surface-FIDA we are able to distinguish Scrapie infected hamster as well as BSE infected cattle in the clinical stage from a control group (3). Preliminary data showed good tendencies that surface FIDA is adaptive to cerebrospinal fluid of cattle. (1) Safar et al. (1998) Nature Med. 4, 1157-1160 (2) Safar et al. (2002) Nat Biotechnol, 20, 1147-1150 (3) Birkmann et al. (2006) Biol. Chem., 387, 95-102
AD E. Birkmann, F. Henke, D. Riesner: Institut for Physical Biology, Heinrich-Heine-Universität, Düsseldorf, Germany; D. Willbold: Research Centre Jülich, Germany. E-mail: birkmann@biophys.uni-duesseldorf.de
SP englisch
PO Italien