NR ATLJ
AU König,C.; Engemann,C.; Krummrei,U.; Wacker,R.; Hoffmann,R.W.
TI Highly sensitive detection of prions - new opportunities in the diagnosis of transmissible spongiform encephalopathies
QU International Conference - Prion 2005: Between fundamentals and society's needs - 19.10.-21.10.2005, Congress Center Düsseldorf - Poster Session: Diagnosis DIA-47
PT Konferenz-Poster
AB
Transmissible spongiform encephalopathies (TSEs) are fatal disorders of the central nervous system characterised by the progressive accumulation of an abnormal form of the prion protein (PrP). TSEs include scrapie in sheep, bovine spongiform encephalopathy (BSE) in cattle, and Creutzfeldt-Jakob disease (CJD) in humans. It was shown that BSE can be transmitted by the consumption of meat products from BSE infected cattle. The transmission causes the new variant of CJD (nvCJD) in humans. NvCJD can be transmitted by blood transfusions and transplantations. A general screening of all donors is essential because, due to the slow etiopathology, the infection risk of a transplant can be unperceived. Thus, our ambition was the development of a detection system for prions in body fluids. At present, there are no methods available that allow the detection of PrPsc in body fluids, because of the extremely low concentrations expected. Therefore a substantial increase in sensitivity of prion detection systems is necessary.
On the basis of a classical ELISA we could establish such a highly sensitive detection system by using a set of different prion specific antibodies and by optimisation of their combination. In a second step sensitivity was increased by biotinylation of the detection antibody and the use of a poly-HRP-streptavidin conjugate. A further enhancement in sensitivity could be obtained by the use of a new detection technique, the so called Immuno-PCR. The Immuno-PCR combines the specific antigen-antibody-reaction with the high amplification rate in PCR. Using Immuno-PCR, sensitivity of the corresponding classical ELISA can be increased up to 10.000 fold.
Based on this system we obtain high sensitivities that permit PrPsc detection in body fluids.
IN Die Autorinnen steigerten nach eigenen Angaben die Empfindlichkeit ihres ELISA-TSE-Tests um mehr als das Tausendfache, indem sie ihre Nachweisantikörper mit einer DNA koppelten, welche mittels PCR zur Signalverstärkung genutzt wird. Diese Empfindlichkeit reicht ihrer Ansicht nach aus, um TSE-Infektionen im Blut nachzuweisen. Allerdings konnte der Leipziger Test die EFSA nicht überzeugen.
AD Christina König, Dr. Claudia Engemann, Dr. Ulrike Krummrei, Labor Diagnostik Leipzig; Germany; Dr. Ron Wacker; Chimera Biotec GmbH; Germany; Christina König, Prof. Ralf Hoffmann, Biotechnologisch-Biomedizinisches Zentrum Universität Leipzig; Germany
SP englisch
PO Deutschland