NR ATHA
AU Segarra,C.S.; Lehmann,S.L.; Coste,J.C.
TI Codon 129 polymorphism of the human prion gene does not influence prion protein expression and processing in peripheral blood cells
QU International Conference - Prion 2005: Between fundamentals and society's needs - 19.10.-21.10.2005, Congress Center Düsseldorf - Poster Session: Cell Biology of PrPc and PrPsc CELL-06
PT Konferenz-Poster
AB
Recently, a novel variant of Creutzfeldt-Jakob disease (vCJD) linked to Bovine Spongiform Encephalopathy has emerged. This new form of human prion diseases represents a serious threat for the general population as its transmission through blood transfusion was suggested in two independent studies. Importantly, all cases of symptomatic vCJD were reported to be methionine homozygous (M/M) at the M129V polymorphism of the PRNP gene. M129V genotype has been also shown to modulate the appearance and/or the phenotype of iatrogenic and sporadic CJD. Incidentally, it is well recognized that the cellular isoform of the prion protein (PrPc) is the essential biochemical substrate for the generation of the pathological isoform PrPsc. Moreover, in different experimental models, levels, processing or post- translational modifications of PrPc influence the disease process.
The aim of our study was therefore to investigate in peripheral blood cells differences in PrPc expression and processing depending on the M129V polymorphism, which could account for distinctive susceptibility to vCJD. We compared blood cells of three populations with M/M, M/V, and V/V genotypes for mRNA expression, PrPc level and processing. Genotyping was assessed by analysis of the temperature melting curves, and mRNA quantification by a Real Time RT-PCR assay. Total PrPc levels were evaluated using an ELISA kit (SpiBio) as well as by SDS-PAGE and immunoblot. Using different antibodies and PNGase F digestion, the glycosylation and the cleavages of PrPc were also studied.
We could not detect any significant differences between the three genotypes for all these parameters. This suggests that the link between M129V polymorphism, blood transmission and vCJD does not rely directly on the biology of PrP in peripheral blood cells.
IN Bei peripheren menschlichen Blutzellen wurden hinsichtlich der Transkription, der PrPc-Konzentration und der posttranslationalen Modifikationen des Prionproteins keine Unterschiede zwischen Menschen mit den Genotypen M/M, M/V und V/V am Codon 129 gefunden.
AD C.S.Segarra, J.C.Coste, Etablissement Français du Sang , Montpellier, France; S.L.Lehmann, Institut de génétique Humaine du CNRS, Montpellier France
SP englisch
PO Deutschland