Originally from: Farmtalking
                        
Hi Francis! – Here's the comlete press release – Jane

 
19 May 2004 Evidence for scrapie prions in muscle tissue of animals prior to onset of clinical disease

Scientists from Berlin and Göttingen (Germany) discover, how scrapie agent spreads to muscles The infectious agent causing transmissible spongiform encephalopathies (TSEs) or prion diseases such as scrapie can be detected in muscle tissues before clinical symptoms become visible.The scrapie agent is able to propagate in muscle tissue to which it apparently spreads via nerves from the brain or spinal cord, as scientists from the Robert Koch-Institute in Berlin and the Department of Neuropathology at the University of Goettingen (both in Ger-many) have discovered.

In the current issue of the American Journal of Clinical Investigation (JCI, Vol. 113, No. 10, 1465–1472) the authors report new findings in their well-established model of alimentarily acquired scrapie which in the past has pro-vided fundamental insights into the pathways of spread of TSE agents through the body of scrapie-infected sheep and BSE-infected cattle. From the results of the present study, which was in part funded by the Volkswagen Foundation (Niedersächsisches Vorab)and the German Federal Ministries of Education and Science (BMBF) and Health and Social Security (BMGS), the authors hope to gain also new insights into the course of variant Creutzfeldt-Jakob disease in humans.

As reported in the JCI article, spoors of spreading scrapie agent were initially detectable after eighty percent of the incubation time in muscles of limbs, head and tongue from hamsters without clinical symptoms, which had been infected with contaminated feed. Further experiments revealed that scrapie could be transmitted to other animals via muscle tissue. Using a sophisticated detection method (PET blot), the researchers were also able to visualize the location of disease-specific prion protein in muscle and nerve tissue so that the dissemination pathways of the scrapie agent could be tracked down.

The brain was found to be infected before transmissible scrapie agent was detectable in muscles. The heads of the two research groups involved in this study, Dr. Michael Beekes (Robert Koch-Institute) and Dr. Walter Schulz-Schaeffer (Department of Neuropathology, University of Goettingen), agree that if the results of their experimental study proved to be also valid in principle for BSE in cattle and scrapie in sheep, routine TSE tests such as those currently mandatory in the European Community should identify affected animals with high reliability. This would provide an efficient precautionary measure to prevent muscle tissue potentially contaminated with infectious TSE agent from entering the food chain.

Last but not least, the reported findings emphasise the necessity of complying in hospitals and medical practices with the precautionary hygiene measures recommended by the Robert Koch-Institut and other public health institutions to prevent accidental transmission of CJD or vCJD from unrecognized carriers.

Contact:
Dr. Walter Schulz-Schaeffer, Prion and Dementia Research Unit, Department of Neuropathology, Georg-August-Universität Göttingen, Bereich Humanmedizin, Robert-Koch-Str. 40, 37075 Göttingen, Tel.: +49 (0) 551 39 2700 or +49 (0) 551 39 2707 E-mail: ...

Dr. Michael Beekes, Robert Koch-Institut (P26), Nordufer 20, 13353 Berlin, Tel.: +49 (0) 30 4547 2396, Fax +49 (0) 30 4547 2267
E-mail: ...

Further information:
Homepage of the Journal of Clinical Investigation: http://www.jci.org

This press release is also available in the internet under http://www.volkswagenstiftung.de/presse-news/presse04/19052004.htm