Characterization of the First Case of Classical Scrapie in a Sheep in Tunisia

Figure 2

PrP^res analyses of pons and cerebellum samples from scrapie-affected sheep from Tunisia show characteristics (i.e., molecular weight of the nonglycosylated band (a); SAF84/P4 ratio relative to the scrapie control (b); proportions of diglycosylated and monoglycosylated PrP^res bands (c)) comparable to classical scrapie: (c). (a) Western blot analysis of proteinase K (PK)—treated PrP^Sc in brain homogenates from a suspect case of sheep scrapie, Tunisia. Two brain areas (pons and cerebellum) from case 19/185 were analyzed along with an isolate of classical scrapie (CS) from an Italian sheep (indicated as CS control). According to ISS-WB protocol, the membranes were probed with SAF84 and P4 monoclonal antibodies (as indicated on the bottom of the blots). The molecular weight markers (Biorad) were loaded in each gel (Marker) indicating 10, 15, 20, 25, 37, and 50 kDa. (b) Bar graph showing the antibody ratio (SAF84/P4 ratio) of the chemiluminescence signal for the samples of pons and cerebellum from case 19/185 shown in (a), relative to the SAF84/P4 ratio of the control scrapie, according to ISS-WB. The horizontal dashed line refers to the cut-off value of the antibody ratio, according to the ISS-WB protocol (antibody ratio 2). (c) Scattergraph of proportions of diglycosylated and monoglycosylated PrP^res bands from sheep case 19/185 in comparison to those previously reported for small ruminants with classical scrapie and BSE [36]. In green are indicated classical scrapie isolates, in black the samples from sheep experimentally infected with BSE, and in red the two samples from brain of sheep 19/185.

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