Skip to main content
. 2019 Dec 16;116(52):26853–26862. doi: 10.1073/pnas.1915737116

Table 3.

Protein Misfolding Cyclic Amplification seeding activity in atypical scrapie isolates

Isolates PMCA positive reactions
Identifiant Origin Genotype TgBov substrate TgARQ substrate
AS 1 Fr ARQ*/ARQ 3/12 5/12
AS 2 Sp ARR/ARQ 2/12 3/12
AS 3 Sp ARQ/ARH 3/12 4/18
AS 4 No ARQ*/AFRQ 12/12 9/12
AS 5 Sp ARQ/ARQ 4/12 3/12
AS 6 Sp ARQ/ARH 5/12 1/12
AS 7 It ARQ/AHQ 1/12 2/12
AS 8 Po ARQ/ARQ ND ND
AS 9 Nor ARR/ARQ 0/12 2/10
AS 10 — ARQ*/AHQ 1/12 0/10
AS 11 — AHQ/ARQ 3/12 7/12
AS 12 — ARR/ARQ 0/12 0/12
AS 13 — ARR/AHQ 0/12 0/12
AS 14 — ARQ/AHQ 1/12 1/12
AS 15 — ARR/ARR 3/12 1/12
AS 16 — ARR/AHQ 1/12 3/10
AS 17 — ARQ*/AHQ 1/12 1/10
AS 18 — ARQ*/AHQ 0/12 0/10
AS 19 Po ARR/ARR 0/12 0/12
AS 20 — ARR/AHQ 3/12 1/12
AS 21 — ARR/ARR 0/12 0/10
AS 22 — ARQ*/AHQ 0/12 0/12
AS 23 — ARQ*/ARQ 1/12 1/12
AS 24 — ARQ*/ARQ 2/12 4/12
AS 25 Fr AHQ/AHQ 0/12 1/12
AS 26 — ARQ/ARQ 1/12 1/12
TSE free sheep — ARQ/ARQ 0/12 0/12
Unseeded — — 0/120 0/120

Twenty-six AS scrapie cases (1/50 diluted 10% brain homogenates) originating from 5 different countries (France [Fr], Spain [Sp], Italy [It], Portugal [Po] and Norway [Nor]) were used to seed PMCA reactions (5 µL of seed per reaction). The AS affected animals displayed different Prnp genotypes at codons 136, 154, and 171. Two different PMCA substrates were used. The first one was prepared using brains from transgenic mice overexpressing the ARQ variant of the sheep prion protein (tgARQ). The second was prepared using brains from transgenic mice overexpressing the bovine prion protein (tgBov). For each isolate and substrate, 10 to 18 individual replicates were tested. Reactions were subjected to 3 amplification rounds. After each round, reaction products (1 volume) were mixed with fresh substrate (9 volumes) to seed the following round. PMCA reaction products (third amplification round) were analyzed by Western blot for the presence of PrPres. The number of PrPres Western blot positive reactions/total number of reactions are reported. Unseeded reactions and reactions seeded with brain homogenate prepared from a TSE-free sheep were included as specificity controls. ND, not done.

*

F/L dimorphism displayed at codon 141.