title: Cell-free propagation of prion strains.
abstract: Prions are the infectious agents responsible for prion diseases, which appear to be composed exclusively by the misfolded prion protein (PrP(Sc)). Disease is transmitted by the autocatalytic propagation of PrP(Sc) misfolding at the expense of the normal prion protein. The biggest challenge of the prion hypothesis has been to explain the molecular mechanism by which prions can exist as different strains, producing diseases with distinguishable characteristics. Here, we show that PrP(Sc) generated in vitro by protein misfolding cyclic amplification from five different mouse prion strains maintains the strain-specific properties. Inoculation of wild-type mice with in vitro-generated PrP(Sc) caused a disease with indistinguishable incubation times as well as neuropathological and biochemical characteristics as the parental strains. Biochemical features were also maintained upon replication of four human prion strains. These results provide additional support for the prion hypothesis and indicate that strain characteristics can be faithfully propagated in the absence of living cells, suggesting that strain variation is dependent on PrP(Sc) properties.
authors.affiliation: Department of Neurology, University of Texas Medical Branch, Galveston, TX 77555, USA.
authors.forename: Joaquín
authors.initials: J
authors.lastname: Castilla
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Morales
authors.forename: Paula
authors.initials: P
authors.lastname: Saá
authors.forename: Marcelo
authors.initials: M
authors.lastname: Barria
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Gambetti
authors.forename: Claudio
authors.initials: C
authors.lastname: Soto
mesh_terms: D000818:Animals; D001921:Brain / Q000033:anatomy & histology / Q000378:metabolism; D002474:Cell-Free System; D005260:Female; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D018620:PrPSc Proteins / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D017096:Prion Diseases / Q000378:metabolism / Q000473:pathology; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D014020:Tissue Extracts / Q000378:metabolism
chemical_list: D018620:PrPSc Proteins; D020033:Protein Isoforms; D014020:Tissue Extracts
references.citation: Nature. 2004 Mar 18;428(6980):319-23
references.pmid: 15029195
references.citation: Science. 1998 Jan 2;279(5347):42-3
references.pmid: 9441410
references.citation: Br Med Bull. 2003;66:1-20
references.pmid: 14522845
references.citation: Biochim Biophys Acta. 2007 Jun;1772(6):681-91
references.pmid: 17254754
references.citation: J Comp Pathol. 1973 Jan;83(1):29-40
references.pmid: 4199908
references.citation: Nat Rev Mol Cell Biol. 2007 Jul;8(7):552-61
references.pmid: 17585315
references.citation: Nature. 1998 Jan 22;391(6665):345-6
references.pmid: 9450747
references.citation: Methods Mol Biol. 2005;299:53-65
references.pmid: 15980595
references.citation: Nature. 1996 Oct 24;383(6602):685-90
references.pmid: 8878476
references.citation: Proc Natl Acad Sci U S A. 2007 Jun 5;104(23):9741-6
references.pmid: 17535913
references.citation: J Virol. 2005 Aug;79(16):10796-806
references.pmid: 16051871
references.citation: Cell. 2005 Apr 22;121(2):195-206
references.pmid: 15851027
references.citation: Annu Rev Biochem. 2004;73:617-56
references.pmid: 15189155
references.citation: Yeast. 1995 Dec;11(16):1671-85
references.pmid: 8720070
references.citation: Trends Neurosci. 2002 Aug;25(8):390-4
references.pmid: 12127750
references.citation: Br Med Bull. 2003;66:213-39
references.pmid: 14522861
references.citation: Annu Rev Neurosci. 2001;24:519-50
references.pmid: 11283320
references.citation: J Vet Med B Infect Dis Vet Public Health. 2005 Mar;52(2):55-63
references.pmid: 15752263
references.citation: Nature. 2001 Jun 14;411(6839):810-3
references.pmid: 11459061
references.citation: Br Med Bull. 2003;66:99-108
references.pmid: 14522852
references.citation: Vet Microbiol. 2007 Aug 31;123(4):346-57
references.pmid: 17493773
references.citation: Science. 1996 Dec 20;274(5295):2079-82
references.pmid: 8953038
references.citation: EMBO J. 2005 Sep 7;24(17):3082-92
references.pmid: 16096644
references.citation: J Biol Chem. 2006 Nov 17;281(46):35245-52
references.pmid: 16982620
references.citation: J Gen Virol. 1991 Mar;72 ( Pt 3):595-603
references.pmid: 1672371
references.citation: J Virol. 1992 Apr;66(4):2096-101
references.pmid: 1347795
references.citation: Proc Natl Acad Sci U S A. 1998 Nov 10;95(23):13363-83
references.pmid: 9811807
references.citation: Nat Med. 2004 Jul;10 Suppl:S63-7
references.pmid: 15272271
references.citation: Nat Med. 1998 Oct;4(10):1157-65
references.pmid: 9771749
references.citation: Cold Spring Harb Symp Quant Biol. 2004;69:489-96
references.pmid: 16117685
references.citation: Trends Biochem Sci. 2002 Dec;27(12):606-12
references.pmid: 12468229
references.citation: Trends Microbiol. 2000 Apr;8(4):157-8
references.pmid: 10754572
references.citation: Arch Virol Suppl. 2000;(16):209-16
references.pmid: 11214924
references.citation: FEBS Lett. 2005 Jan 31;579(3):638-42
references.pmid: 15670821
references.citation: Annu Rev Microbiol. 2002;56:703-41
references.pmid: 12142498
references.citation: Nature. 1991 Aug 22;352(6337):679-83
references.pmid: 1876183
references.citation: Nat Rev Microbiol. 2004 Nov;2(11):861-71
references.pmid: 15494743
references.citation: Brain. 2003 Jun;126(Pt 6):1333-46
references.pmid: 12764055
references.citation: Methods Enzymol. 2006;412:3-21
references.pmid: 17046648
references.citation: Sci Prog. 1976 Winter;63(252):461-81
references.pmid: 823641
references.citation: Nature. 2004 Mar 18;428(6980):323-8
references.pmid: 15029196
references.citation: J Gen Virol. 2002 Mar;83(Pt 3):695-704
references.pmid: 11842264
references.citation: J Biol Chem. 1998 Nov 27;273(48):32230-5
references.pmid: 9822701
references.citation: Philos Trans R Soc Lond B Biol Sci. 1994 Mar 29;343(1306):413-4
references.pmid: 7913759
references.citation: Science. 2004 Jul 30;305(5684):673-6
references.pmid: 15286374
references.citation: Philos Trans R Soc Lond B Biol Sci. 1994 Mar 29;343(1306):425-30
references.pmid: 7913761