Specific inhibition of pathological prion protein accumulation by small interfering RNAs.
Development of transmissible spongiform encephalopathies (TSEs) pathogenesis requires the presence of both the normal host prion protein (PrP-sen) and the abnormal pathological proteinase-K resistant isoform (PrP-res). PrP-res forms highly insoluble aggregates, with self-perpetuating properties, by binding and converting PrP-sen molecules into a likeness of themselves. In the present report, we show that small interfering RNA (siRNA) duplexes trigger specific Prnp gene silencing in scrapie-infected neuroblastoma cells. A non-passaged, scrapie-infected culture transfected with siRNA duplexes is depleted of PrP-sen and rapidly loses its PrP-res content. The use of different murine-adapted scrapie strains and host cells did not influence the siRNA-induced gene silencing efficiency. More than 80% of transfected cells were positive for the presence of fluorescein-labeled siRNA duplexes. No cytotoxicity associated with the use of siRNA was observed during the time course of these experiments. Despite a transient abrogation of PrP-res accumulation, our results suggest that the use of siRNA may provide a new and promising therapeutic approach against prion diseases.
Daude
Nathalie
N
Institut de Pharmacologie Moléculaire et Cellulaire, Unité Mixte de Recherche 6097, Centre National de la Recherche Scientifique. 660, route des lucioles, 06560 Valbonne, France.
Marella
Mathieu
M
Chabry
Joelle
J
D000818:Animals; D045744:Cell Line, Tumor; D019793:Fluorescein; D020868:Gene Silencing / Q000187:drug effects / Q000502:physiology*; D051379:Mice; D018621:PrPC Proteins / Q000235:genetics / Q000378:metabolism; D018620:PrPSc Proteins / Q000096:biosynthesis* / Q000235:genetics; D017096:Prion Diseases / Q000235:genetics / Q000378:metabolism* / Q000628:therapy; D034622:RNA Interference / Q000502:physiology*; D034741:RNA, Small Interfering / Q000235:genetics* / Q000494:pharmacology; D012608:Scrapie / Q000235:genetics / Q000378:metabolism / Q000628:therapy; D014162:Transfection / Q000379:methods / Q000639:trends
D018621:PrPC Proteins; D018620:PrPSc Proteins; D034741:RNA, Small Interfering; D019793:Fluorescein