Cell fusion induced by scrapie and Creutzfeldt-Jakob virus-infected brain preparations.

Cell fusion was induced by brain extracts containing the scrapie virus and the virus of Creutzfeldt-Jakob disease. The assay involved quantitation of colony-forming ability in a double selection system, strandardized against fusion induced by Sendai virus. Correlation between the logarithm of virus dilution and the hybrid colony number gave similar curves for scrapie virus and Sendai virus. Fusion induction may explain some aspects of pathogenesis in these diseases and provide a potential in vitro assay.