Late increase of serum S100 beta protein levels in hamsters after oral or intraperitoneal infection with scrapie

Following recent reports of elevated serum S100 beta protein (S100 beta) le vels in patients with genetic and sporadic Creutzfeldt-Jakob disease and in rodents parenterally infected with scrapie, the suitability of serum S100 beta as a preclinical marker for transmissible spongiform encephalopathies was assessed in time-course studies. Syrian hamsters were orally and intrap eritoneally challenged with scrapie and assayed for serum S100 beta levels at various times after infection. Although elevated serum S100 beta levels were consistently observed in terminally ill animals for both routes of inf ection, the experiments failed to detect significantly increased S100 beta serum concentrations prior to the manifestation of clinical symptoms. Thus, in this animal model, serum S100 beta does not appear to be an appropriate marker for the preclinical detection of scrapie, but it may provide a conv enient laboratory aid for the diagnosis of transmissible spongiform encepha lopathy in naturally or accidentally infected animals and humans.