Detection of proteinase K-resistant prion protein and infectivity in mouse spleen by 2 weeks after scrapie agent inoculation

J Gen Virol. 1992 Dec;73 ( Pt 12):3319-23. doi: 10.1099/0022-1317-73-12-3319.


The sequential accumulation of the protease-resistant form of the endogenous prion protein (PrP-res) was compared to levels of scrapie infectivity in the spleen and brain of scrapie-infected mice at various times after inoculation. In mouse spleen PrP-res was detected 1 week after inoculation, and increased 65-fold between 1 and 3 weeks post-inoculation and an additional 15-fold during the next 17 weeks. Infectivity in spleen reached a maximum plateau level by 3 weeks. In contrast, in mouse brain PrP-res was not detected until 8 weeks after inoculation and then increased 200-fold during the next 12 weeks. During this same time, infectivity increased approximately 10,000-fold. Therefore, in both spleen and brain of scrapie-infected mice accumulation of PrP-res and infectivity appear to be associated. However, it was not possible to show quantitative correlations between PrP-res detection and infectivity, perhaps owing to the inaccuracy of the infectivity assay.

MeSH terms

  • Animals
  • Brain Chemistry
  • Endopeptidase K
  • Mice
  • PrPSc Proteins
  • Prions / chemistry*
  • Prions / metabolism
  • Scrapie / physiopathology
  • Scrapie / transmission*
  • Serine Endopeptidases / pharmacology
  • Spleen / chemistry
  • Time Factors


  • PrPSc Proteins
  • Prions
  • Serine Endopeptidases
  • Endopeptidase K