The Scripps Research Institute, Scripps Florida
Current address: Yale University School of Medicine
The nature of the infectious agent causing scrapie and other Transmissible Spongiform Encephalopathies remains an enigma despite decades of research efforts. The protein-only prion hypothesis posits that abnormal conformer of a host protein is the infectious agent. Virus and virino theories include host- independent nucleic acid as the genome of the infectious agent in addition to protein component (in case of virino a host protein and in case of virus a viral protein). Viral or sub-viral nucleic acids have long been sought in scrapie to explain the existence of multiple agent strains.
Many different approaches were undertaken to find such nucleic acid. Despite that no scrapie specific nucleic acid sequences have been found in infected cells or tissues.
Most viruses induce synthesis of long double stranded RNA (dsRNA) during their replication in cells. Therefore the presence of long dsRNA would be an indication of viral infection in cells. J2 monoclonal antibody against long dsRNA is a great tool for easy screening of cells and tissues for the presence of suspected unknown viral infection.
This antibody has not been used for testing of scrapie infected tissues.
Evidence is presented here for long dsRNA in scrapie infected cells and tissues. Such dsRNA is also found in scrapie free tissue culture cells.