Molecular and Transmission Characteristics of Primary-Passaged Ovine Scrapie Isolates in Conventional and Ovine PrP Transgenic Mice

ABSTRACT A more complete assessment of ovine prion strain diversity will be achieved by complementing biological strain typing in conventional and ovine PrP transgenic mice with a biochemical analysis of the resultant PrPSc. This will provide a correlation between ovine prion strain phenotype and the molecular nature of different PrP conformers associated with particular prion strains. Here, we have compared the molecular and transmission characteristics of ovine ARQ/ARQ and VRQ/VRQ scrapie isolates following primary passage in tg338 (VRQ) and tg59 (ARQ) ovine PrP transgenic mice and the conventional mouse lines C57BL/6 (Prnp a ), RIII (Prnp a ), and VM (Prnp b ). Our data show that these different genotypes of scrapie isolates display similar incubation periods of >350 days in conventional and tg59 mice. Facilitated transmission of sheep scrapie isolates occurred in tg338 mice, with incubation times reduced to 64 days for VRQ/VRQ inocula and to ≤210 days for ARQ/ARQ samples. Distinct genotype-specific lesion profiles were seen in the brains of conventional and tg59 mice with prion disease, which was accompanied by the accumulation of more conformationally stable PrPSc, following inoculation with ARQ/ARQ compared to VRQ/VRQ scrapie isolates. In contrast, the lesion profiles, quantities, and stability of PrPSc induced by the same inocula in tg338 mice were more similar than in the other mouse lines. Our data show that primary transmission of different genotypes of ovine prions is associated with the formation of different conformers of PrPSc with distinct molecular properties and provide the basis of a molecular approach to identify the true diversity of ovine prion strains.

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The Region Approximately between Amino Acids 81 and 137 of Proteinase K-Resistant PrPSc Is Critical for the Infectivity of the Chandler Prion Strain

Journal of Virology ◽

10.1128/jvi.01740-08 ◽

2009 ◽

Vol 83 (8) ◽

pp. 3852-3860 ◽

Cited By ~ 18

Author(s):

Ryo Shindoh ◽

Chan-Lan Kim ◽

Chang-Hyun Song ◽

Rie Hasebe ◽

Motohiro Horiuchi

Keyword(s):

Amino Acids ◽

Guanidine Hydrochloride ◽

Conformational Stability ◽

Terminal Region ◽

Proteinase K ◽

Prion Strain ◽

Prion Infectivity ◽

Prion Strains ◽

Incubation Periods ◽

The Relationship

ABSTRACT Although the major component of the prion is believed to be the oligomer of PrPSc, little information is available concerning regions on the PrPSc molecule that affect prion infectivity. During the analysis of PrPSc molecules from various prion strains, we found that PrPSc of the Chandler strain showed a unique property in the conformational-stability assay, and this property appeared to be useful for studying the relationship between regions of the PrPSc molecule and prion infectivity. Thus, we analyzed PrPSc of the Chandler strain in detail and analyzed the infectivities of the N-terminally denatured and truncated forms of proteinase K-resistant PrP. The N-terminal region of PrPSc of the Chandler strain showed region-dependent resistance to guanidine hydrochloride (GdnHCl) treatment. The region approximately between amino acids (aa) 81 and 137 began to be denatured by treatment with 1.5 M GdnHCl. Within this stretch, the region comprising approximately aa 81 to 90 was denatured almost completely by 2 M GdnHCl. Furthermore, the region approximately between aa 90 and 137 was denatured completely by 3 M GdnHCl. However, the C-terminal region thereafter was extremely resistant to the GdnHCl treatment. This property was not observed in PrPSc molecules of other prion strains. Denaturation of the region between aa 81 and 137 by 3 M GdnHCl significantly prolonged the incubation periods in mice compared to that for the untreated control. More strikingly, the denaturation and removal of this region nearly abolished the infectivity. This finding suggests that the conformation of the region between aa 81 and 137 of the Chandler strain PrPSc molecule is directly associated with prion infectivity.

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Bovine adapted transmissible mink encephalopathy is similar to L-BSE after passage through sheep with the VRQ/VRQ genotype but not VRQ/ARQ

10.21203/rs.3.rs-31096/v2 ◽

2020 ◽

Author(s):

E.D. Cassmann ◽

S.J. Moore ◽

R.D. Kokemuller ◽

A. Balkema-Buschmann ◽

M. H. Groschup ◽

...

Keyword(s):

Prion Protein ◽

Transmission Efficiency ◽

Interspecies Transmission ◽

Transmission Characteristics ◽

Host Genotype ◽

Disease Phenotypes ◽

Prion Strains ◽

Incubation Periods ◽

Human Prion Protein ◽

Transmissible Mink Encephalopathy

Abstract BackgroundTransmissible mink encephalopathy (TME) is a fatal neurologic disease of farmed mink. Evidence indicates that TME and L-BSE are similar and may be linked in some outbreaks of TME. We previously transmitted bovine adapted TME (bTME) to sheep. The present study compared ovine passaged bTME (o-bTME) to C-BSE and L-BSE in transgenic mice expressing wild type bovine prion protein (TgBovXV). To directly compare the transmission efficiency of all prion strains in this study, we considered the attack rates and mean incubation periods. Additional methods for strain comparison were utilized including lesion profiles, fibril stability, and western blotting. ResultsSheep donor genotype elicited variable disease phenotypes in bovinized mice. Inoculum derived from a sheep with the VRQ/VRQ genotype (o-bTMEVV) resulted in an attack rate, incubation period, western blot profile, and neuropathology most similar to bTME and L-BSE. Conversely, donor material from a sheep with the VRQ/ARQ genotype (o-bTMEAV) elicited a phenotype distinct from o-bTMEVV, bTME and L-BSE. The TSE with the highest transmission efficiency in bovinized mice was L-BSE. The tendency to efficiently transmit to TgBovXV mice decreased in the order bTME, C-BSE, o-bTMEVV, and o-bTMEAV. The transmission efficiency of L-BSE was approximately 1.3 times higher than o-bTMEVV and 3.2 times higher than o-bTMEAV.ConclusionsOur findings provide insight on how sheep host genotype modulates strain genesis and influences interspecies transmission characteristics. Given that the transmission efficiencies of L-BSE and bTME are higher than C-BSE, coupled with previous reports of L-BSE transmission to mice expressing the human prion protein, continued monitoring for atypical BSE is advisable in order to prevent occurrences of interspecies transmission that may affect humans or other species.

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Host Determinants of Prion Strain Diversity Independent of Prion Protein Genotype

Journal of Virology ◽

10.1128/jvi.01586-15 ◽

2015 ◽

Vol 89 (20) ◽

pp. 10427-10441 ◽

Cited By ~ 23

Author(s):

Jenna Crowell ◽

Andrew Hughson ◽

Byron Caughey ◽

Richard A. Bessen

Keyword(s):

Transgenic Mice ◽

Prion Protein ◽

Protein Gene ◽

Phenotypic Diversity ◽

Prion Diseases ◽

Conformational Stability ◽

Epigenetic Mechanism ◽

Prion Strain ◽

Disease Phenotypes ◽

Prion Strains

ABSTRACTPhenotypic diversity in prion diseases can be specified by prion strains in which biological traits are propagated through an epigenetic mechanism mediated by distinct PrPScconformations. We investigated the role of host-dependent factors on phenotypic diversity of chronic wasting disease (CWD) in different host species that express the same prion protein gene (Prnp). Two CWD strains that have distinct biological, biochemical, and pathological features were identified in transgenic mice that express the Syrian golden hamster (SGH)Prnp. The CKY strain of CWD had a shorter incubation period than the WST strain of CWD, but after transmission to SGH, the incubation period of CKY CWD was ∼150 days longer than WST CWD. Limited proteinase K digestion revealed strain-specific PrPScpolypeptide patterns that were maintained in both hosts, but the solubility and conformational stability of PrPScdiffered for the CWD strains in a host-dependent manner. WST CWD produced PrPScamyloid plaques in the brain of the SGH that were partially insoluble and stable at a high concentration of protein denaturant. However, in transgenic mice, PrPScfrom WST CWD did not assemble into plaques, was highly soluble, and had low conformational stability. Similar studies using the HY and DY strains of transmissible mink encephalopathy resulted in minor differences in prion biological and PrPScproperties between transgenic mice and SGH. These findings indicate that host-specific pathways that are independent ofPrnpcan alter the PrPScconformation of certain prion strains, leading to changes in the biophysical properties of PrPSc, neuropathology, and clinical prion disease.IMPORTANCEPrions are misfolded pathogenic proteins that cause neurodegeneration in humans and animals. Transmissible prion diseases exhibit a spectrum of disease phenotypes and the basis of this diversity is encoded in the structure of the pathogenic prion protein and propagated by an epigenetic mechanism. In the present study, we investigated prion diversity in two hosts species that express the same prion protein gene. While prior reports have demonstrated that prion strain properties are stable upon infection of the same host species and prion protein genotype, our findings indicate that certain prion strains can undergo dramatic changes in biological properties that are not dependent on the prion protein. Therefore, host factors independent of the prion protein can affect prion diversity. Understanding how host pathways can modify prion disease phenotypes may provide clues on how to alter prion formation and lead to treatments for prion, and other, human neurodegenerative diseases of protein misfolding.

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Emergence of multiple prion strains from single isolates of ovine scrapie

Journal of General Virology ◽

10.1099/vir.0.028886-0 ◽

2011 ◽

Vol 92 (6) ◽

pp. 1482-1491 ◽

Cited By ~ 47

Author(s):

Alana M. Thackray ◽

Lee Hopkins ◽

Richard Lockey ◽

John Spiropoulos ◽

Raymond Bujdoso

Keyword(s):

Transgenic Mice ◽

Incubation Time ◽

Infectious Agent ◽

Serial Passage ◽

Molecular Profile ◽

Strain Typing ◽

Wild Type ◽

Diverse Range ◽

Prion Strain ◽

Prion Strains

The infectious agent associated with prion diseases such as ovine scrapie shows strain diversity. Ovine prion strains have typically been identified by their transmission properties in wild-type mice. However, strain typing of ovine scrapie isolates in wild-type mice may not reveal properties of the infectious prion agent as they exist in the original host. This could be circumvented if ovine scrapie isolates are passaged in ovine prion protein (PrP)-transgenic mice. This study used incubation time, lesion profile, immunohistochemistry of the disease-associated PrP (PrPSc) and molecular profile to compare the range of ovine prion strains that emerged from sheep scrapie isolates following serial passage in wild-type and ovine PrP transgenic mice. It was found that a diverse range of ovine prion strains emerged from homozygous ARQ and VRQ scrapie isolates passaged in wild-type and ovine PrP transgenic mice. However, strain-specific PrPSc deposition and PrP27–30 molecular profile patterns were identified in ovine PrP transgenic mice that were not detected in wild-type mice. Significantly, it was established that the individual mouse brain selected for transmission during prion strain typing had a significant influence on strain definition. Serial passage of short- and long-incubation-time animals from the same group of scrapie-inoculated mice revealed different prion strain phenotypes. These observations are consistent with the possibility that some scrapie isolates contain more than one prion strain.

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Bovine adapted transmissible mink encephalopathy is similar to L-BSE after passage through sheep with the VRQ/VRQ genotype but not VRQ/ARQ

10.21203/rs.3.rs-31096/v1 ◽

2020 ◽

Author(s):

E.D. Cassmann ◽

S.J. Moore ◽

R.D. Kokemuller ◽

A. Balkema-Buschmann ◽

M. H. Groschup ◽

...

Keyword(s):

Prion Protein ◽

Transmission Efficiency ◽

Interspecies Transmission ◽

Transmission Characteristics ◽

Host Genotype ◽

Disease Phenotypes ◽

Prion Strains ◽

Incubation Periods ◽

Human Prion Protein ◽

Transmissible Mink Encephalopathy

Abstract Background Transmissible mink encephalopathy (TME) is a fatal neurologic disease of farmed mink. Evidence indicates that TME and L-BSE are similar and may be linked in some outbreaks of TME. We previously transmitted bovine adapted TME (bTME) to sheep. The present study compared ovine passaged bTME (o-bTME) to C-BSE and L-BSE in transgenic mice expressing wild type bovine prion protein (TgBovXV). To directly compare the transmission efficiency of all prion strains in this study, we considered the attack rates and mean incubation periods. Additional methods for strain comparison were utilized including lesion profiles, fibril stability, and western blotting. Results Sheep donor genotype elicited variable disease phenotypes in bovinized mice. Inoculum derived from a sheep with the VRQ/VRQ genotype (o-bTMEVV) resulted in an attack rate, incubation period, western blot profile, and neuropathology most similar to bTME and L-BSE. Conversely, donor material from a sheep with the VRQ/ARQ genotype (o-bTMEAV) elicited a phenotype distinct from o-bTMEVV, bTME and L-BSE. The TSE with the highest transmission efficiency in bovinized mice was L-BSE. The tendency to efficiently transmit to TgBovXV mice decreased in the order bTME, C-BSE, o-bTMEVV, and o-bTMEAV. The transmission efficiency of L-BSE was approximately 1.3 times higher than o-bTMEVV and 3.2 times higher than o-bTMEAV. Conclusions Our findings provide insight on how sheep host genotype modulates strain genesis and influences interspecies transmission characteristics. Given that the transmission efficiencies of L-BSE and bTME are higher than C-BSE, coupled with previous reports of L-BSE transmission to mice expressing the human prion protein, continued monitoring for atypical BSE is advisable in order to prevent occurrences of interspecies transmission that may affect humans or other species.

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Bovine adapted transmissible mink encephalopathy is similar to L-BSE after passage through sheep with the VRQ/VRQ genotype but not VRQ/ARQ

BMC Veterinary Research ◽

10.1186/s12917-020-02611-0 ◽

2020 ◽

Vol 16 (1) ◽

Author(s):

Eric Cassmann ◽

Sarah Jo Moore ◽

Robyn Kokemuller ◽

Anne Balkema-Buschmann ◽

Martin Groschup ◽

...

Keyword(s):

Prion Protein ◽

Transmission Efficiency ◽

Interspecies Transmission ◽

Transmission Characteristics ◽

Host Genotype ◽

Disease Phenotypes ◽

Prion Strains ◽

Incubation Periods ◽

Human Prion Protein ◽

Transmissible Mink Encephalopathy

Abstract Background Transmissible mink encephalopathy (TME) is a fatal neurologic disease of farmed mink. Evidence indicates that TME and L-BSE are similar and may be linked in some outbreaks of TME. We previously transmitted bovine adapted TME (bTME) to sheep. The present study compared ovine passaged bTME (o-bTME) to C-BSE and L-BSE in transgenic mice expressing wild type bovine prion protein (TgBovXV). To directly compare the transmission efficiency of all prion strains in this study, we considered the attack rates and mean incubation periods. Additional methods for strain comparison were utilized including lesion profiles, fibril stability, and western blotting. Results Sheep donor genotype elicited variable disease phenotypes in bovinized mice. Inoculum derived from a sheep with the VRQ/VRQ genotype (o-bTMEVV) resulted in an attack rate, incubation period, western blot profile, and neuropathology most similar to bTME and L-BSE. Conversely, donor material from a sheep with the VRQ/ARQ genotype (o-bTMEAV) elicited a phenotype distinct from o-bTMEVV, bTME and L-BSE. The TSE with the highest transmission efficiency in bovinized mice was L-BSE. The tendency to efficiently transmit to TgBovXV mice decreased in the order bTME, C-BSE, o-bTMEVV, and o-bTMEAV. The transmission efficiency of L-BSE was approximately 1.3 times higher than o-bTMEVV and 3.2 times higher than o-bTMEAV. Conclusions Our findings provide insight on how sheep host genotype modulates strain genesis and influences interspecies transmission characteristics. Given that the transmission efficiencies of L-BSE and bTME are higher than C-BSE, coupled with previous reports of L-BSE transmission to mice expressing the human prion protein, continued monitoring for atypical BSE is advisable in order to prevent occurrences of interspecies transmission that may affect humans or other species.

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Bovine adapted transmissible mink encephalopathy is similar to L-BSE after passage through sheep with the VRQ/VRQ genotype but not VRQ/ARQ

10.21203/rs.3.rs-31096/v3 ◽

2020 ◽

Author(s):

E.D. Cassmann ◽

S.J. Moore ◽

R.D. Kokemuller ◽

A. Balkema-Buschmann ◽

M. H. Groschup ◽

...

Keyword(s):

Prion Protein ◽

Transmission Efficiency ◽

Interspecies Transmission ◽

Transmission Characteristics ◽

Host Genotype ◽

Disease Phenotypes ◽

Prion Strains ◽

Incubation Periods ◽

Human Prion Protein ◽

Transmissible Mink Encephalopathy

Abstract Background Transmissible mink encephalopathy (TME) is a fatal neurologic disease of farmed mink. Evidence indicates that TME and L-BSE are similar and may be linked in some outbreaks of TME. We previously transmitted bovine adapted TME (bTME) to sheep. The present study compared ovine passaged bTME (o-bTME) to C-BSE and L-BSE in transgenic mice expressing wild type bovine prion protein (TgBovXV). To directly compare the transmission efficiency of all prion strains in this study, we considered the attack rates and mean incubation periods. Additional methods for strain comparison were utilized including lesion profiles, fibril stability, and western blotting. Results Sheep donor genotype elicited variable disease phenotypes in bovinized mice. Inoculum derived from a sheep with the VRQ/VRQ genotype (o-bTMEVV) resulted in an attack rate, incubation period, western blot profile, and neuropathology most similar to bTME and L-BSE. Conversely, donor material from a sheep with the VRQ/ARQ genotype (o-bTMEAV) elicited a phenotype distinct from o-bTMEVV, bTME and L-BSE. The TSE with the highest transmission efficiency in bovinized mice was L-BSE. The tendency to efficiently transmit to TgBovXV mice decreased in the order bTME, C-BSE, o-bTMEVV, and o-bTMEAV. The transmission efficiency of L-BSE was approximately 1.3 times higher than o-bTMEVV and 3.2 times higher than o-bTMEAV.Conclusions Our findings provide insight on how sheep host genotype modulates strain genesis and influences interspecies transmission characteristics. Given that the transmission efficiencies of L-BSE and bTME are higher than C-BSE, coupled with previous reports of L-BSE transmission to mice expressing the human prion protein, continued monitoring for atypical BSE is advisable in order to prevent occurrences of interspecies transmission that may affect humans or other species.

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Chimeric elk/mouse prion proteins in transgenic mice

Journal of General Virology ◽

10.1099/vir.0.045989-0 ◽

2013 ◽

Vol 94 (2) ◽

pp. 443-452 ◽

Cited By ~ 11

Author(s):

Gültekin Tamgüney ◽

Kurt Giles ◽

Abby Oehler ◽

Natrina L. Johnson ◽

Stephen J. DeArmond ◽

...

Keyword(s):

Neurodegenerative Disorder ◽

Prion Proteins ◽

Second Line ◽

Mouse Line ◽

Wasting Disease ◽

C Terminus ◽

Incubation Periods ◽

N Terminus ◽

Mouse Lines

Chronic wasting disease (CWD) of deer and elk is a highly communicable neurodegenerative disorder caused by prions. Investigations of CWD are hampered by slow bioassays in transgenic (Tg) mice. Towards the development of Tg mice that will be more susceptible to CWD prions, we created a series of chimeric elk/mouse transgenes that encode the N terminus of elk PrP (ElkPrP) up to residue Y168 and the C terminus of mouse PrP (MoPrP) beyond residue 169 (mouse numbering), designated Elk3M(SNIVVK). Between codons 169 and 219, six residues distinguish ElkPrP from MoPrP: N169S, T173N, V183I, I202V, I214V and R219K. Using chimeric elk/mouse PrP constructs, we generated 12 Tg mouse lines and determined incubation times after intracerebral inoculation with the mouse-passaged RML scrapie or Elk1P CWD prions. Unexpectedly, one Tg mouse line expressing Elk3M(SNIVVK) exhibited incubation times of <70 days when inoculated with RML prions; a second line had incubation times of <90 days. In contrast, mice expressing full-length ElkPrP had incubation periods of >250 days for RML prions. Tg(Elk3M,SNIVVK) mice were less susceptible to CWD prions than Tg(ElkPrP) mice. Changing three C-terminal mouse residues (202, 214 and 219) to those of elk doubled the incubation time for mouse RML prions and rendered the mice resistant to Elk1P CWD prions. Mutating an additional two residues from mouse to elk at codons 169 and 173 increased the incubation times for mouse prions to >300 days, but made the mice susceptible to CWD prions. Our findings highlight the role of C-terminal residues in PrP that control the susceptibility and replication of prions.

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Coinfecting Prion Strains Compete for a Limiting Cellular Resource

Journal of Virology ◽

10.1128/jvi.00243-10 ◽

2010 ◽

Vol 84 (11) ◽

pp. 5706-5714 ◽

Cited By ~ 55

Author(s):

Ronald A. Shikiya ◽

Jacob I. Ayers ◽

Charles R. Schutt ◽

Anthony E. Kincaid ◽

Jason C. Bartz

Keyword(s):

Protein Misfolding ◽

Neuronal Loss ◽

Infectious Agent ◽

Prion Strain ◽

Prion Strains ◽

The Central Nervous System ◽

Transmissible Mink Encephalopathy ◽

Prion Conversion ◽

Cellular Components

ABSTRACT Prion strain interference can influence the emergence of a dominant strain from a mixture; however, the mechanisms underlying prion strain interference are poorly understood. In our model of strain interference, inoculation of the sciatic nerve with the drowsy (DY) strain of the transmissible mink encephalopathy (TME) agent prior to superinfection with the hyper (HY) strain of TME can completely block HY TME from causing disease. We show here that the deposition of PrPSc, in the absence of neuronal loss or spongiform change, in the central nervous system corresponds with the ability of DY TME to block HY TME infection. This suggests that DY TME agent-induced damage is not responsible for strain interference but rather prions compete for a cellular resource. We show that protein misfolding cyclic amplification (PMCA) of DY and HY TME maintains the strain-specific properties of PrPSc and replicates infectious agent and that DY TME can interfere, or completely block, the emergence of HY TME. DY PrPSc does not convert all of the available PrPC to PrPSc in PMCA, suggesting the mechanism of prion strain interference is due to the sequestering of PrPC and/or other cellular components required for prion conversion. The emergence of HY TME in PMCA was controlled by the initial ratio of the TME agents. A higher ratio of DY to HY TME agent is required for complete blockage of HY TME in PMCA compared to several previous in vivo studies, suggesting that HY TME persists in animals coinfected with the two strains. This was confirmed by PMCA detection of HY PrPSc in animals where DY TME had completely blocked HY TME from causing disease.

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