[Influence of ultrasonic processing on the aggregation of PrP-Sc in the brain extracts of the scrapie-infected hamsters].
BACKGROUND
To evaluate the influence ultrasonic processing on the aggregation of PrP(Sc) in the brain extracts prepared from the scrapie-infected hamsters, and to seek for the way to prepare lower molecular PrP(Sc) polymer.


METHODS
The extracts of infected brains were prepared with a lysis solution, and treated with ultrasonics at various conditions during the different phases. The distribution and aggregation state of PrP(Sc) were analyzed by proteinase K treated. Western blot, and afterwards, quantitatively calculated with a commercially supplied software Image Totaltech.


RESULTS
The amount of PrP(Sc) in the supernatant of brain homogenates was 1.29-to 1.58-fold increased with appropriate sonication (15 s for 30 times). At the same conditions of ultrasound, the PrP amount in the supernatant prepared from the scrapie-infected hamster brain was significantly increased, whereas that prepared from healthy animal used as normal control showed little change. Comparative analyses of PrP(Sc) pellets prepared by high-speed centrifugation revealed that about 90% PrP(Sc) released into supernatant after ultrasound processing.


CONCLUSIONS
Appropriate sonication of homogenate of scrapie-infected brain increases the extracted amount of PrP(Sc), being favorable to laboratory diagnosis. Larger molecular PrP(Sc) aggregates can be crashed by ultrasonic processing, engendering lower molecular PrP(Sc) polymers.
Zhou
Xiao-bo
XB
Institute for Viral Disease Control and Prevention, China CDC, Beijing 100052, China.
Gao
Jian-mei
JM
Gao
Chen
C
Zhang
Bao-yun
BY
Yuan
Yu-kang
YK
Dong
Xiao-ping
XP
D000818:Animals; D015153:Blotting, Western; D001923:Brain Chemistry; D006224:Cricetinae; D007091:Image Processing, Computer-Assisted; D018620:PrPSc Proteins / Q000032:analysis*; D012608:Scrapie / Q000378:metabolism*; D013010:Sonication
D018620:PrPSc Proteins