1
|
Madsen-Bouterse SA, Highland MA, Dassanayake RP, Zhuang D, Schneider DA. Low-volume goat milk transmission of classical scrapie to lambs and goat kids. PLoS One 2018; 13:e0204281. [PMID: 30235307 PMCID: PMC6147516 DOI: 10.1371/journal.pone.0204281] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 09/04/2018] [Indexed: 01/21/2023] Open
Abstract
The risk of classical scrapie transmission in small ruminants is highest during the neonatal period with the placenta recognized as a significant source of infection. Milk has also been identified as a source of scrapie with sheep-to-sheep transmission occurring after neonatal consumption of as little as 1-2 liters of milk; concurrent mastitis due to small ruminant lentivirus (SRLV) infection may be associated with increased scrapie transmission via milk in sheep. In contrast, goat-to-sheep transmission has been documented only after prolonged consumption of >30 liters of milk. The goal of the current study was to assess transmission of scrapie to goat kids and lambs following low volume, short duration consumption of milk from infected goats. Milk from two does (female goats) with pre-clinical scrapie was fed to four goat kids (≤4.5 L each) and four lambs (~3.7 L each) beginning ~24 hours after birth. Scrapie transmission was detected in three sheep as early as 18 months post inoculation; transmission was also detected in two goats but not until postmortem analyses at 33 months post inoculation. Each milk donor goat also had naturally-acquired infection with SRLV. Different degrees of lymphohistiocytic inflammation and PrPSc accumulation were observed in mammary gland tissues of the donors, which appeared to associate with transmission of scrapie via milk. Thus, similar to the risks of milk transmission of scrapie from sheep, even limited exposure to milk from goats can pose significant risk for scrapie transmission to both goat kids and lambs.
Collapse
Affiliation(s)
- Sally A. Madsen-Bouterse
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
| | - Margaret A. Highland
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, Washington, United States of America
- Washington Animal Disease Diagnostic Laboratory, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
- Paul G. Allen School for Global Animal Health, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
| | - Rohana P. Dassanayake
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
| | - Dongyue Zhuang
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, Washington, United States of America
| | - David A. Schneider
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, Washington, United States of America
| |
Collapse
|
2
|
Dassanayake RP, Zhuang D, Truscott TC, Madsen-Bouterse SA, O'Rourke KI, Schneider DA. A transfectant RK13 cell line permissive to classical caprine scrapie prion propagation. Prion 2017; 10:153-64. [PMID: 27216989 DOI: 10.1080/19336896.2016.1166324] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
To assess scrapie infectivity associated with caprine-origin tissues, bioassay can be performed using kids, lambs or transgenic mice expressing caprine or ovine prion (PRNP) alleles, but the incubation periods are fairly long. Although several classical ovine scrapie prion permissive cell lines with the ability to detect brain-derived scrapie prion have been available, no classical caprine scrapie permissive cell line is currently available. Therefore, the aims of this study were to generate a rabbit kidney epithelial cell line (RK13) stably expressing caprine wild-type PRNP (cpRK13) and then to assess permissiveness of cpRK13 cells to classical caprine scrapie prion propagation. The cpRK13 and plasmid control RK13 (pcRK13) cells were incubated with brain-derived classical caprine scrapie inocula prepared from goats or ovinized transgenic mice (Tg338, express ovine VRQ allele) infected with caprine scrapie. Significant PrP(Sc) accumulation, which is indicative of scrapie prion propagation, was detected by TSE ELISA and immunohistochemistry in cpRK13 cells inoculated with classical caprine scrapie inocula. Western blot analysis revealed the typical proteinase K-resistant 3 PrP(res) isoforms in the caprine scrapie prion inoculated cpRK13 cell lysate. Importantly, PrP(Sc) accumulation was not detected in similarly inoculated pcRK13 cells, whether by TSE ELISA, immunohistochemistry, or western blot. These findings suggest that caprine scrapie prions can be propagated in cpRK13 cells, thus this cell line may be a useful tool for the assessment of classical caprine prions in the brain tissues of goats.
Collapse
Affiliation(s)
- Rohana P Dassanayake
- a Department of Veterinary Microbiology and Pathology , College of Veterinary Medicine, Washington State University , Pullman , WA , USA
| | - Dongyue Zhuang
- b Animal Disease Research Unit, Agricultural Research Service , U.S. Department of Agriculture , Pullman , WA , USA
| | - Thomas C Truscott
- b Animal Disease Research Unit, Agricultural Research Service , U.S. Department of Agriculture , Pullman , WA , USA
| | - Sally A Madsen-Bouterse
- a Department of Veterinary Microbiology and Pathology , College of Veterinary Medicine, Washington State University , Pullman , WA , USA
| | - Katherine I O'Rourke
- a Department of Veterinary Microbiology and Pathology , College of Veterinary Medicine, Washington State University , Pullman , WA , USA
| | - David A Schneider
- a Department of Veterinary Microbiology and Pathology , College of Veterinary Medicine, Washington State University , Pullman , WA , USA ;,b Animal Disease Research Unit, Agricultural Research Service , U.S. Department of Agriculture , Pullman , WA , USA
| |
Collapse
|
3
|
Konold T, Thorne L, Simmons HA, Hawkins SAC, Simmons MM, González L. Evidence of scrapie transmission to sheep via goat milk. BMC Vet Res 2016; 12:208. [PMID: 27640200 PMCID: PMC5027119 DOI: 10.1186/s12917-016-0807-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 08/19/2016] [Indexed: 11/25/2022] Open
Abstract
Background Previous studies confirmed that classical scrapie can be transmitted via milk in sheep. The current study aimed to investigate whether scrapie can also be transmitted via goat milk using in vivo (new-born lambs fed milk from scrapie-affected goats due to the unavailability of goat kids from guaranteed scrapie-free herds) and in vitro methods (serial protein misfolding cyclic amplification [sPMCA] on milk samples). Results In an initial pilot study, new-born lambs of two different prion protein gene (PRNP) genotypes (six VRQ/VRQ and five ARQ/ARQ) were orally challenged with 5 g brain homogenate from two scrapie-affected goats to determine susceptibility of sheep to goat scrapie. All sheep challenged with goat scrapie brain became infected based on the immunohistochemical detection of disease-associated PrP (PrPsc) in lymphoid tissue, with an ARQ/ARQ sheep being the first to succumb. Subsequent feeding of milk to eight pairs of new-born ARQ/ARQ lambs, with each pair receiving milk from a different scrapie-affected goat, resulted in scrapie in the six pairs that received the largest volume of milk (38–87 litres per lamb), whereas two pairs fed 8–9 litres per lamb, and an environmental control group raised on sheep milk from healthy ewes, did not show evidence of infection when culled at up to 1882 days of age. Infection in those 12 milk recipients occurred regardless of the clinical status, PrPsc distribution, caprine arthritis-encephalitis virus infection status and PRNP polymorphisms at codon 142 (II or IM) of the donor goats, but survival time was influenced by PRNP polymorphisms at codon 141. Serial PMCA applied to a total of 32 milk samples (four each from the eight donor goats collected throughout lactation) detected PrPsc in one sample each from two goats. Conclusions The scrapie agent was present in the milk from infected goats and was able to transmit to susceptible species even at early preclinical stage of infection, when PrPsc was undetectable in the brain of the donor goats. Serial PMCA as a PrPsc detection method to assess the risk of scrapie transmission via milk in goats proved inefficient compared to the bioassay. Electronic supplementary material The online version of this article (doi:10.1186/s12917-016-0807-4) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Timm Konold
- Animal Sciences Unit, Animal and Plant Health Agency Weybridge, New Haw, Addlestone, Surrey, KT15 3NB, UK.
| | - Leigh Thorne
- Virology Department, Animal and Plant Health Agency Weybridge, New Haw, Addlestone, Surrey, KT15 3NB, UK
| | - Hugh A Simmons
- Animal Sciences Unit, Animal and Plant Health Agency Weybridge, New Haw, Addlestone, Surrey, KT15 3NB, UK
| | - Steve A C Hawkins
- Pathology Department, Animal and Plant Health Agency Weybridge, New Haw, Addlestone, Surrey, KT15 3NB, UK
| | - Marion M Simmons
- Pathology Department, Animal and Plant Health Agency Weybridge, New Haw, Addlestone, Surrey, KT15 3NB, UK
| | - Lorenzo González
- Pathology Department, Animal and Plant Health Agency Lasswade, Pentlands Science Park, Bush Loan, Penicuik, Midlothian, EH26 0PZ, UK
| |
Collapse
|
4
|
Antiprion Activity of DB772 and Related Monothiophene- and Furan-Based Analogs in a Persistently Infected Ovine Microglia Culture System. Antimicrob Agents Chemother 2016; 60:5467-82. [PMID: 27381401 PMCID: PMC4997874 DOI: 10.1128/aac.00811-16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 06/26/2016] [Indexed: 01/26/2023] Open
Abstract
The transmissible spongiform encephalopathies are fatal neurodegenerative disorders characterized by the misfolding of the native cellular prion protein (PrPC) into the accumulating, disease-associated isoform (PrPSc). Despite extensive research into the inhibition of prion accumulation, no effective treatment exists. Previously, we demonstrated the inhibitory activity of DB772, a monocationic phenyl-furan-benzimidazole, against PrPSc accumulation in sheep microglial cells. In an effort to determine the effect of structural substitutions on the antiprion activity of DB772, we employed an in vitro strategy to survey a library of structurally related, monothiophene- and furan-based compounds for improved inhibitory activity. Eighty-nine compounds were screened at 1 μM for effects on cell viability and prion accumulation in a persistently infected ovine microglia culture system. Eleven compounds with activity equivalent to or higher than that of DB772 were identified as preliminary hit compounds. For the preliminary hits, cytotoxicities and antiprion activities were compared to calculate the tissue culture selectivity index. A structure-activity relationship (SAR) analysis was performed to determine molecular components contributing to antiprion activity. To investigate potential mechanisms of inhibition, effects on PrPC and PrPSc were examined. While inhibition of total PrPC was not observed, the results suggest that a potential target for inhibition at biologically relevant concentrations is through PrPC misfolding to PrPSc. Further, SAR analysis suggests that two structural elements were associated with micromolar antiprion activity. Taken together, the described data provide a foundation for deeper investigation into untested DB compounds and in the design of effective therapeutics.
Collapse
|
5
|
Dassanayake RP, Madsen-Bouterse SA, Truscott TC, Zhuang D, Mousel MR, Davis WC, Schneider DA. Classical scrapie prions are associated with peripheral blood monocytes and T-lymphocytes from naturally infected sheep. BMC Vet Res 2016; 12:27. [PMID: 26847623 PMCID: PMC4743119 DOI: 10.1186/s12917-016-0651-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 01/31/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Classical scrapie is a transmissible spongiform encephalopathy (TSE) that affects sheep and goats. Our previous bioassay studies in lambs revealed that scrapie prions could be detected in association with peripheral blood monocular cells (PBMC), B lymphocytes and platelet-rich plasma fractions. In the present study, bioassay in lambs was again used to determine if scrapie prions are associated with the other two subsets of PBMC, monocytes and T lymphocytes. RESULTS PBMC, monocytes and T lymphocytes were isolated from two preclinically affected VRQ/VRQ sheep naturally infected with classical ovine scrapie and intravenously transfused into VRQ/VRQ lambs post-weaning. As determined using standard immunohistochemistry for scrapie, abnormal isoforms of prion protein were detected in lymphoid tissues of lambs inoculated with PBMC (4/4 recipient lambs), monocytes (2/5) and T lymphocytes (1/4). Prion protein misfolding activity was detected by serial protein misfolding cyclic amplification (sPMCA) in PBMC from monocyte and T lymphocyte recipient sheep in agreement with antemortem rectal biopsy results, but such prion protein misfolding activity was not detected from other recipients. CONCLUSIONS These findings show that scrapie prions are associated with monocytes and T lymphocytes circulating in the peripheral blood of sheep naturally infected with classical scrapie. Combined with our previous findings, we can now conclude that all three major subsets of PBMC can harbor prions during preclinical disease and thus, present logical targets for development of a sensitive assay to detect scrapie prions. In this regard, we have also demonstrated that sPMCA can be used to detect scrapie prions associated with PBMC.
Collapse
Affiliation(s)
- Rohana P Dassanayake
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, 99164-6630, USA.
| | - Sally A Madsen-Bouterse
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, 99164-6630, USA.
| | - Thomas C Truscott
- Animal Disease Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Pullman, WA, 99164-6630, USA.
| | - Dongyue Zhuang
- Animal Disease Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Pullman, WA, 99164-6630, USA.
| | - Michelle R Mousel
- Animal Disease Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Pullman, WA, 99164-6630, USA.
| | - William C Davis
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, 99164-6630, USA.
| | - David A Schneider
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, 99164-6630, USA. .,Animal Disease Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Pullman, WA, 99164-6630, USA.
| |
Collapse
|
6
|
Dassanayake RP, Orrú CD, Hughson AG, Caughey B, Graça T, Zhuang D, Madsen-Bouterse SA, Knowles DP, Schneider DA. Sensitive and specific detection of classical scrapie prions in the brains of goats by real-time quaking-induced conversion. J Gen Virol 2015; 97:803-812. [PMID: 26653410 DOI: 10.1099/jgv.0.000367] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Real-time quaking-induced conversion (RT-QuIC) is a rapid, specific and highly sensitive prion seeding activity detection assay that uses recombinant prion protein (rPrPSen) to detect subinfectious levels of the abnormal isoforms of the prion protein (PrPSc). Although RT-QuIC has been successfully used to detect PrPSc in various tissues from humans and animals, including sheep, tissues from goats infected with classical scrapie have not yet been tested. Therefore, the aims of the present study were to (1) evaluate whether prion seeding activity could be detected in the brain tissues of goats with scrapie using RT-QuIC, (2) optimize reaction conditions to improve scrapie detection in goats, and (3) compare the performance of RT-QuIC for the detection of PrPSc with the more commonly used ELISA and Western blot assays. We further optimized RT-QuIC conditions for sensitive and specific detection of goat scrapie seeding activity in brain tissue from clinical animals. When used with 200 mM sodium chloride, both full-length sheep rPrPSen substrates (PrP genotypes A136R154Q171 and V136R154Q171) provided good discrimination between scrapie-infected and normal goat brain samples at 10(- )3 dilution within 15 h. Our findings indicate that RT-QuIC was at least 10,000-fold more sensitive than ELISA and Western blot assays for the detection of scrapie seeding activity in goat brain samples. In addition to PRNP WT samples, positive RT-QuIC reactions were also observed with three PRNP polymorphic goat brain samples (G/S127, I/M142 and H/R143) tested. Taken together, these findings demonstrate that RT-QuIC sensitively detects prion seeding activity in classical scrapie-infected goat brain samples.
Collapse
Affiliation(s)
- Rohana P Dassanayake
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164-7040, USA
| | - Christina D Orrú
- Rocky Mountain Laboratories, National Institute for Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA
| | - Andrew G Hughson
- Rocky Mountain Laboratories, National Institute for Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA
| | - Byron Caughey
- Rocky Mountain Laboratories, National Institute for Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA
| | - Telmo Graça
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164-7040, USA.,The Paul G. Allen School for Global Animal Health, College of Veterinary Medicine, Washington State University, Pullman, WA 99164-7090, USA
| | - Dongyue Zhuang
- Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, Pullman, WA 99164-6630, USA
| | - Sally A Madsen-Bouterse
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164-7040, USA
| | - Donald P Knowles
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164-7040, USA.,Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, Pullman, WA 99164-6630, USA
| | - David A Schneider
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164-7040, USA.,Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, Pullman, WA 99164-6630, USA
| |
Collapse
|