An experimental examination of the scrapie agent in cell membrane mixtures: III. Studies of the operational size

• Published in: Journal of comparative pathology Vol. 81; no. 3; pp. 383 - 391
• Main Authors: Kimberlin, R.H., Millson, G.C., Hunter, G.D.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 1971
• Subjects: mice
• ISSN: 0021-9975; 1532-3129
• DOI: 10.1016/0021-9975(71)90026-0

Membrane preparations from scrapie-affected mouse brain were ultrasonicated, passed through filters of 50 nm and 20 to 35 nm pore size and the filtrates analysed using exclusion chromatography, isopycnic sedimentation and electron microscopy. A high recovery of scrapie activity was found in the 50 nm filtrates and all evidence indicated association of this activity with membrane fragments. Although a significant amount of lipoprotein material was recovered in 20 to 35 nm filtrates, membrane fragments were absent and no scrapie activity was found. These observations are consistent with the membrane hypothesis of scrapie: it is suggested that the operational size of the agent is much larger than the radiation target size.