Proteolytic inactivation of the bovine spongiform encephalopathy agent.
Thermostable proteases have been investigated for their ability to provide a novel biological solution to decontamination of prion agents responsible for transmissible spongiform encephalopathies (TSEs). Proteases were identified that digested total mouse brain homogenate (MBH) protein from uninfected mice. These proteases were then evaluated for digestion of BSE (301V) infectious MBH over a range of pH and temperatures, screened for loss of anti-prion antibody 6H4 immunoreactivity and protease-treated infectious MBH assessed in mouse bioassay using VM mice. Despite a number of proteases eliminating all 6H4-immunoreactive material, only the subtilisin-enzyme Properase showed a significant extension in incubation period in mouse bioassays following a 30-min incubation at 60 degrees C and pH 12. These results demonstrate the potential of the method to provide a practical solution to the problems of TSE contamination of surgical instruments and highlight the inadequacy of using Western blot for assessment of decontamination/inactivation of TSE agents.
McLeod
Anne H
AH
Health Protection Agency, Porton Down, Salisbury, Wiltshire SP4 0JG, UK.
Murdoch
Heather
H
Dickinson
Jo
J
Dennis
Mike J
MJ
Hall
Graham A
GA
Buswell
Clive M
CM
Carr
Jean
J
Taylor
David M
DM
Sutton
J Mark
JM
Raven
Neil D H
ND
D000818:Animals; D001681:Biological Assay; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism; D002417:Cattle; D003666:Decontamination; D016643:Encephalopathy, Bovine Spongiform / Q000378:metabolism*; D010450:Endopeptidases / Q000378:metabolism*; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D051379:Mice; D011328:Prions / Q000276:immunology / Q000378:metabolism*; D016019:Survival Analysis; D013696:Temperature
D011328:Prions; D010450:Endopeptidases