NR AXIQ
AU Barbieri,I.; Brocchi,E.; Capucci,L.
TI Molecular Properties of BSE and BASE Agents following Denaturation Assessed by a Panel of Monoclonal Antibodies
QU International Conference - Prion 2007 (26.-28.9.2007) Edinburgh International Conference Centre, Edinburgh, Scotland, UK - Book of Abstracts: Natural and Experimental Strains P02.22
IA http://www.prion2007.com/pdf/Prion Book of Abstracts.pdf
PT Konferenz-Poster
AB
For a long time BSE has been thought to be caused by a unique prion strain (C-type) with stable and specific lesion profile, molecular features and glycotype in which the diglycosylated form of PrP was predominant. Despite, the occurrence of atypical BSE cases in a number of European countries has pointed out the existence of at least two further BSE strains with distinctive biochemical properties. In particular, in Italy two atypical BSE cases were found in more than 10 year old cattle which were characterized by a different type of disease associated PrP (L-Type) showing a lower molecular weight of the unglycosylated isoform, predominance of the monoglycosylated dominant and a peculiar deposition pattern in the brain compared to typical Italian BSE .
In order to gather further information on the molecular features of C-type and L-type PrP, samples from BSE- and BASE-affected cattle underwent treatment with various concentrations of denaturing agents such as guanidine and urea whose use in conformation stability assays to accomplish molecular strain typing of various TSE agents has been reported.
Reactivity of denatured BSE and BASE samples was then assessed by means of a well characterized panel of monoclonal antibodies (MAbs) that can efficiently detect both strains and by the reference MAb 6H4. Preliminary results showed that 6M guanidine, followed by proteinase K (PK) digestion, completely abolished the reactivity of L-type with 6H4 and C-terminal MAbs, while C-type PrP was still detectable though to a lower extent. After 4 and 8 M urea treatment both C-Type and L-Type PrP were detectable but a reduction in signal intensity was observed in samples treated with the highest concentration.
Taken together this data indicated that, as well known, C-Type and L-Type PrP are denatured by guanidine and urea but, interestingly, L-type seemed to be less stable to high guanidine concentrations than C-Type. This suggests the existence different molecular properties between the BSE and BASE strains that may also account for their distinct biological properties recently highlighted in transmission experiments in mice.
AD I. Barbieri, L. Capucci, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Molecular Biology, Italy; E. Brocchi, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Biotechnology, Italy
SP englisch
PO Schottland
EA pdf-Datei und Poster (Postertitel: Biochemical properties of BSE and BASE agents following denaturation assessed monoclonal antibodies)