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Pabst A, Becker P, Götz W, Heimes D, Thiem DGE, Blatt S, Kämmerer PW. A comparative analysis of particulate bovine bone substitutes for oral regeneration: a narrative review. Int J Implant Dent 2024; 10:26. [PMID: 38801622 PMCID: PMC11130110 DOI: 10.1186/s40729-024-00544-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Accepted: 05/21/2024] [Indexed: 05/29/2024] Open
Abstract
PURPOSE Particulate bovine bone substitutes (BS) are commonly used in oral regeneration. However, more literature is needed focusing on comparative analyses among various particulate bovine BS. This study evaluates pre-clinical and clinical data of different particulate bovine BS in oral regeneration. METHODS A narrative review was conducted by screening the PubMed database Included in the review were pre-clinical and clinical studies until 2024 comparing a minimum of two distinct particulate bovine BS. In addition to examining general data concerning manufacturing and treatment processes, biological safety, physical and chemical characteristics, and graft resorption, particular emphasis was placed on assessing pre-clinical and clinical data related to ridge preservation, sinus floor elevation, peri-implant defects, and various forms of alveolar ridge augmentation utilizing particulate bovine BS. RESULTS Various treatment temperatures ranging from 300 to 1,250 °C and the employment of chemical cleaning steps were identified for the manufacturing process of particulate bovine BS deemed to possess biosecurity. A notable heterogeneity was observed in the physical and chemical characteristics of particulate bovine BS, with minimal or negligible graft resorption. Variations were evident in particle and pore sizes and the porosity of particulate bovine BS. Pre-clinical assessments noted a marginal inclination towards favorable outcomes for particulate bovine BS subjected to higher treatment temperatures. However, clinical data are insufficient. No distinctions were observed regarding ridge preservation, while slight advantages were noted for high-temperature treated particulate bovine BS in sinus floor elevation. CONCLUSIONS Subtle variances in both pre-clinical and clinical outcomes were observed in across various particulate bovine BS. Due to inadequate data, numerous considerations related to diverse particulate bovine BS, including peri-implant defects, must be more conclusive. Additional clinical studies are imperative to address these knowledge gaps effectively.
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Affiliation(s)
- Andreas Pabst
- Department of Oral and Maxillofacial Surgery, German Armed Forces Central Hospital, Rübenacherstraße 170, 56072, Koblenz, Germany
- Department of Oral and Maxillofacial Surgery - Plastic Operations, University Medical Center Mainz, Augustusplatz 2, 55131, Mainz, Germany
| | - Philipp Becker
- Department of Oral and Maxillofacial Surgery, German Armed Forces Central Hospital, Rübenacherstraße 170, 56072, Koblenz, Germany
- Department of Oral and Maxillofacial Surgery - Plastic Operations, University Medical Center Mainz, Augustusplatz 2, 55131, Mainz, Germany
| | - Werner Götz
- Department of Orthodontics, University Hospital Bonn, Welschnonnenstr. 17, 53111, Bonn, Germany
| | - Diana Heimes
- Department of Oral and Maxillofacial Surgery - Plastic Operations, University Medical Center Mainz, Augustusplatz 2, 55131, Mainz, Germany
| | - Daniel G E Thiem
- Department of Oral and Maxillofacial Surgery - Plastic Operations, University Medical Center Mainz, Augustusplatz 2, 55131, Mainz, Germany
| | - Sebastian Blatt
- Department of Oral and Maxillofacial Surgery - Plastic Operations, University Medical Center Mainz, Augustusplatz 2, 55131, Mainz, Germany
| | - Peer W Kämmerer
- Department of Oral and Maxillofacial Surgery - Plastic Operations, University Medical Center Mainz, Augustusplatz 2, 55131, Mainz, Germany.
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Iwamaru Y, Furusaki K, Sugiura K, Haritani M, Onodera T. Ceramic absorbed with calcium bicarbonate mesoscopic crystals partially inactivate scrapie prions. Microbiol Immunol 2023; 67:447-455. [PMID: 37517033 DOI: 10.1111/1348-0421.13092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 06/29/2023] [Accepted: 07/11/2023] [Indexed: 08/01/2023]
Abstract
Prion diseases are fatal neurodegenerative disorders affecting both humans and animals. The causative agent, prion, is extremely resistant to common disinfection procedures. Thus, effective prion inactivation strategies using relatively safe and less corrosive disinfectants are required. A solution containing CAC-717, mesoscopic crystals of calcium bicarbonate, exerts both antimicrobial and virucidal activities without apparent harmful effects. This study demonstrated that combined treatment with CAC-717 absorbed on ceramic (CAC-717 ceramic) and sodium dodecyl sulfate (SDS) substantially reduced the protein misfolding cyclic amplification (PMCA) seeding activity of Chandler strain scrapie mouse-brain homogenates (ScBH). Additionally, bioassays demonstrated that ScBH-inoculated mice treated with CAC-717 ceramic in combination with sodium dodecyl sulfate (SDS) did not develop disease. Furthermore, this combination effectively inactivated PMCA seeding activity on ScBH-coated stainless-steel wires below the detection limit. Overall, the findings suggest that combined treatment with CAC-717 ceramic and SDS represents a promising and less damaging approach for prion inactivation.
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Affiliation(s)
- Yoshifumi Iwamaru
- National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan
| | - Koichi Furusaki
- Mineral Activation Technical Research Center, Omuta, Fukuoka, Japan
| | - Katsuaki Sugiura
- Environmental Science for Sustainable Development, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Makoto Haritani
- Environmental Science for Sustainable Development, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Takashi Onodera
- Environmental Science for Sustainable Development, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
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Kinetics of the reduction of Creutzfeldt-Jakob disease prion seeding activity by steam sterilization support the use of validated 134°C programmes. J Hosp Infect 2023; 132:125-132. [PMID: 36216171 DOI: 10.1016/j.jhin.2022.08.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 08/09/2022] [Accepted: 08/13/2022] [Indexed: 11/12/2022]
Abstract
BACKGROUND Prions are renowned for their distinct resistance to chemical or physical inactivation, including steam sterilization. Impaired efficacy of inactivation poses a risk to patients for iatrogenic transmission of Creutzfeldt-Jakob disease (CJD) via contaminated surgical instruments. AIMS Most established prion inactivation methods were validated against scrapie agents, although those were found to be generally less thermostable than human prions. Thus, knowledge gaps regarding steam-sterilization kinetics of CJD prions should be filled and current guidelines reviewed accordingly. METHODS Prion inactivation through widely recommended steam sterilization at 134°C was assessed for several holding times by analysing the residual prion seeding activity using protein misfolding cyclic amplification (PMCA). FINDINGS Scrapie 263K was found to be the least thermoresistant prion strain showing no seeding activity after 1.5 min at 134°C, while variant CJD was the most stable one demonstrating some seeding activity even after 18 min of steam sterilization. Sporadic CJD subtype VV2 exhibited residual seeding activity after 3 min, but no detectable activity after 5 min at 134°C. CONCLUSION Validated steam sterilization for 5 min at 134°C as previously recommended for the routine reprocessing of surgical instruments in contact with high-risk tissues is able to substantially reduce the seeding activity of CJD agents, provided that no fixating chemical disinfection has been performed prior to sterilization and that thorough cleaning has reduced the protein load on the surface to less than 100 μg per instrument.
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Jerbić Radetić AT, Zoričić Cvek S, Tomas M, Erjavec I, Oguić M, Perić Kačarević Ž, Cvijanović Peloza O. CSBD Healing in Rats after Application of Bovine Xenogeneic Biomaterial Enriched with Magnesium Alloy. Int J Mol Sci 2021; 22:ijms22169089. [PMID: 34445794 PMCID: PMC8396602 DOI: 10.3390/ijms22169089] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 08/14/2021] [Accepted: 08/20/2021] [Indexed: 01/10/2023] Open
Abstract
Xenogeneic biomaterials Cerbone® and OsteoBiol® are widely used in oral implantology. In dental practice, xenogeneic biomaterial is usually combined with autologous bone to provide bone volume stability needed for long-term dental implants. Magnesium alloy implants dissolve and form mineral corrosion layer that is directly in contact with bone tissue, allowing deposition of the newly formed bone. CSBD heals by intramembranous ossification and therefore is a convenient model for analyses of ostoconductive and osteoinductive properties of different type of biomaterials. Magnesium alloy-enriched biomaterials have not yet been applied in oral implantology. Therefore, the aim of the current study was to investigate biological properties of potentially new bovine xenogeneic biomaterial enriched with magnesium alloy in a 5 mm CSBD model. Osteoconductive properties of Cerabone®, Cerabone® + Al. bone, and OsteoBiol® were also analyzed. Dynamics of bone healing was followed up on the days 3, 7, 15, 21, and 30. Calvary bone samples were analyzed by micro-CT, and values of the bone morphometric parameters were assessed. Bone samples were further processed for histological and immunohistochemical analyses. Histological observation revealed CSBD closure at day 30 of the given xenogeneic biomaterial groups, with the exception of the control group. TNF-α showed high intensity of expression at the sites of MSC clusters that underwent ossification. Osx was expressed in pre-osteoblasts, which were differentiated into mature osteoblasts and osteocytes. Results of the micro-CT analyses showed linear increase in bone volume of all xenogeneic biomaterial groups and also in the control. The highest average values of bone volume were found for the Cerabone® + Mg group. In addition, less residual biomaterial was estimated in the Cerabone® + Mg group than in the Cerabone® group, indicating its better biodegradation during CSBD healing. Overall, the magnesium alloy xenogeneic biomaterial demonstrated key properties of osteoinduction and biodegradidibility during CSBD healing, which is the reason why it should be recommended for application in clinical practice of oral implantology.
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Affiliation(s)
| | - Sanja Zoričić Cvek
- Department of Anatomy, Medical Faculty, University of Rijeka, 51 000 Rijeka, Croatia; (A.T.J.R.); (S.Z.C.)
| | - Matej Tomas
- Department of Dental Medicine, Faculty of Dental Medicine and Health Osijek, J.J. Strossmayer University of Osijek, 31 000 Osijek, Croatia;
| | - Igor Erjavec
- Medical Faculty, University of Zagreb, 10 000 Zagreb, Croatia;
| | | | - Željka Perić Kačarević
- Department of Anatomy, Histology, Embryology, Pathology Anatomy and Pathology Histology, Faculty of Dental Medicine and Health Osijek, J.J. Strossmayer University of Osijek, 31 000 Osijek, Croatia;
| | - Olga Cvijanović Peloza
- Department of Anatomy, Medical Faculty, University of Rijeka, 51 000 Rijeka, Croatia; (A.T.J.R.); (S.Z.C.)
- Correspondence: ; Tel.: +385-91-8998-421
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Langeveld JPM, Balkema-Buschmann A, Becher D, Thomzig A, Nonno R, Andréoletti O, Davidse A, Di Bari MA, Pirisinu L, Agrimi U, Groschup MH, Beekes M, Shih J. Stability of BSE infectivity towards heat treatment even after proteolytic removal of prion protein. Vet Res 2021; 52:59. [PMID: 33863379 PMCID: PMC8052740 DOI: 10.1186/s13567-021-00928-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 03/23/2021] [Indexed: 11/25/2022] Open
Abstract
The unconventional infectious agents of transmissible spongiform encephalopathies (TSEs) are prions. Their infectivity co-appears with PrPSc, aberrant depositions of the host's cellular prion protein (PrPC). Successive heat treatment in the presence of detergent and proteolysis by a keratinase from Bacillus licheniformis PWD-1 was shown before to destroy PrPSc from bovine TSE (BSE) and sheep scrapie diseased brain, however data regarding expected reduction of infectivity were still lacking. Therefore, transgenic Tgbov XV mice which are highly BSE susceptible were used to quantify infectivity before and after the bovine brain treatment procedure. Also four immunochemical analyses were applied to compare the levels of PrPSc. After heating at 115 °C with or without subsequent proteolysis, the original BSE infectivity of 106.2-6.4 ID50 g-1 was reduced to a remaining infectivity of 104.6-5.7 ID50 g-1 while strain characteristics were unaltered, even after precipitation with methanol. Surprisingly, PrPSc depletion was 5-800 times higher than the loss of infectivity. Similar treatment was applied on other prion strains, which were CWD1 in bank voles, 263 K scrapie in hamsters and sheep PG127 scrapie in tg338 ovinized mice. In these strains however, infectivity was already destroyed by heat only. These findings show the unusual heat resistance of BSE and support a role for an additional factor in prion formation as suggested elsewhere when producing prions from PrPC. Leftover material in the remaining PrPSc depleted BSE preparation offers a unique substrate for searching additional elements for prion infectivity and improving our concept about the nature of prions.
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Affiliation(s)
- Jan P M Langeveld
- Department of Infection Biology, Wageningen Bioveterinary Research (WBVR), 8221RA 39, Lelystad, The Netherlands.
| | - Anne Balkema-Buschmann
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, 17493, Greifswald-Insel Riems, Germany
| | - Dieter Becher
- MICROMUN, Institut Für Mikrobiologische Forschung GmbH, 17489, Greifswald, Germany
| | - Achim Thomzig
- Prion and Prionoid Research Unit, Robert Koch-Institute, 13353, Berlin, Germany
| | - Romolo Nonno
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore Di Sanità, 00161, Rome, Italy
| | - Olivier Andréoletti
- UMR INRAE/ENVT 1225 IHAP, École Nationale Vétérinaire de Toulouse, 31300, Toulouse, France
| | - Aart Davidse
- Department of Infection Biology, Wageningen Bioveterinary Research (WBVR), 8221RA 39, Lelystad, The Netherlands
| | - Michele A Di Bari
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore Di Sanità, 00161, Rome, Italy
| | - Laura Pirisinu
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore Di Sanità, 00161, Rome, Italy
| | - Umberto Agrimi
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore Di Sanità, 00161, Rome, Italy
| | | | - Michael Beekes
- Prion and Prionoid Research Unit, Robert Koch-Institute, 13353, Berlin, Germany
| | - Jason Shih
- Department of Poultry Science, North Carolina State University, Raleigh, NC, 27695-7608, USA
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Koutsoumanis K, Allende A, Bolton DJ, Bover‐Cid S, Chemaly M, Davies R, De Cesare A, Herman LM, Hilbert F, Lindqvist R, Nauta M, Peixe L, Ru G, Simmons M, Skandamis P, Suffredini E, Andreoletti O, Griffin J, Spiropoulos J, Ortiz‐Pelaez A, Alvarez‐Ordóñez A. Potential BSE risk posed by the use of ruminant collagen and gelatine in feed for non-ruminant farmed animals. EFSA J 2020; 18:e06267. [PMID: 33144887 PMCID: PMC7592076 DOI: 10.2903/j.efsa.2020.6267] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
EFSA was requested to estimate the cattle bovine spongiform encephalopathy (BSE) risk (C-, L- and H-BSE) posed by ruminant collagen and gelatine produced from raw material fit for human consumption, or from material classified as Category 3 animal by-products (ABP), to be used in feed intended for non-ruminant animals, including aquaculture animals. Three risk pathways (RP) were identified by which cattle could be exposed to ruminant feed cross-contaminated with ruminant collagen or gelatine: 1) recycled former foodstuffs produced in accordance with Regulation (EC) No 853/2004 (RP1), 2) technological or nutritional additives or 3) compound feed, produced either in accordance with Regulation (EC) No 853/2004 (RP2a) or Regulation (EU) No 142/2011 (RP2b). A probabilistic model was developed to estimate the BSE infectivity load measured in cattle oral ID 50 (CoID 50)/kg, in the gelatine produced from the bones and hide of one infected animal older than 30 months with clinical BSE (worst-case scenario). The amount of BSE infectivity (50th percentile estimate) in a member state (MS) with negligible risk status was 7.6 × 10-2 CoID 50/kg, and 3.1 × 10-4 CoID 50/kg in a MS with controlled risk status. The assessment considered the potential contamination pathways and the model results (including uncertainties) regarding the current epidemiological situation in the EU and current statutory controls. Given the estimated amount of BSE infectivity to which cattle would be exposed in a single year, and even if all the estimated undetected BSE cases in the EU were used for the production of collagen or gelatine (either using raw materials fit for human consumption or Category 3 ABP raw materials), it was concluded that the probability that no new case of BSE in the cattle population would be generated through any of the three RP is 99-100% (almost certain).
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Matsuura Y, Ishikawa Y, Murayama Y, Yokoyama T, Somerville RA, Kitamoto T, Mohri S. Eliminating transmissibility of bovine spongiform encephalopathy by dry-heat treatment. J Gen Virol 2020; 101:136-142. [PMID: 31718739 DOI: 10.1099/jgv.0.001335] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bovine spongiform encephalopathy (BSE) prion is more resistant to heat inactivation compared to other prions, but the effect of heat inactivation has been reported to differ depending on the BSE-contaminated tissue state or heating type. We aimed to evaluate the secure level of inactivation of original BSE transmissibility by dry-heating. Cattle tissues affected with BSE were subjected to dry-heat treatment for 20 min at various temperatures ranging from 150 to 1000 °C. To assess the inactivation effect, we conducted protein misfolding cyclic amplification (PMCA) and follicular dendritic cell (FDC) assays in transgenic mice expressing bovine prion protein genes. Under dry-heating at 600 °C or higher, BSE cattle tissues lost their transmissibility in transgenic mice. In contrast, transmissibility was detected in the cattle tissues treated at temperatures of 400 °C or lower through the FDC assay combined with PMCA. In this study, we confirmed that transmissibility was eliminated in BSE-affected cattle tissues by dry-heating at 600 °C or higher.
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Affiliation(s)
- Yuichi Matsuura
- National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki 305-0856, Japan
| | - Yukiko Ishikawa
- Present address: International Institute for Integrative Sleep Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan.,National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki 305-0856, Japan
| | - Yuichi Murayama
- Present address: Wildlife Research Center, Kyoto University, 2-24 Tanaka-Sekiden-cho, Sakyo, Kyoto, 606-8203, Japan.,National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki 305-0856, Japan
| | - Takashi Yokoyama
- National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki 305-0856, Japan
| | - Robert A Somerville
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian EH25 9PS, UK
| | - Tetsuyuki Kitamoto
- Department of Neurological Science, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
| | - Shirou Mohri
- National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki 305-0856, Japan.,Department of Neurological Science, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
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Koutsoumanis K, Allende A, Bolton D, Bover-Cid S, Chemaly M, Davies R, De Cesare A, Herman L, Hilbert F, Lindqvist R, Nauta M, Peixe L, Ru G, Simmons M, Skandamis P, Suffredini E, Andréoletti O, Escámez PF, Griffin J, Spiropoulos J, Ashe S, Ortiz-Peláez A, Alvarez-Ordóñez A. Evaluation of an alternative method for production of biodiesel from processed fats derived from Category 1, 2 and 3 animal by-products (submitted by College Proteins). EFSA J 2020; 18:e06089. [PMID: 32874297 PMCID: PMC7448056 DOI: 10.2903/j.efsa.2020.6089] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
An alternative method for the production of biodiesel from processed fats derived from Category 1, 2 and 3 animal by-products was assessed. The method is based on a pre-cleaning process, acidic esterification/transesterification of tallow using 1.5% methanesulfonic acid w/w; 140°C; 5.5 bar absolute pressure (bara); 4 h, followed by fractional distillation. The application focuses on the capacity of the alternative method to inactivate prions. Given the limitations that biodiesel presents for direct measurement of prion infectivity, the BIOHAZ Panel considered, based on the outcome of previous EFSA Opinions and current expert evaluation, that a reduction of 6 log10 in detectable PrPS c signal would be necessary to consider the process at least equivalent to previously approved methods for Category 1 animal by-products. This is in addition to the inactivation achieved by the pressure sterilisation method applied before the application of any biodiesel production method. Experimental data were provided via ad hoc studies commissioned to quantify the reduction in detectable PrPS c in material spiked with scrapie hamster strain 263K, as measured by western blot, for the first two steps, with distillation assumed to provide at least an additional 3 log10 reduction, based on published data. Despite the intrinsic methodological caveats of the detection of PrPS c in laboratory studies, the BIOHAZ Panel considers that the alternative method, including the final fractional distillation, is capable of achieving the required 6 log10 reduction of the strain 263K PrPS c signal. Therefore, the method under assessment can be considered at least equivalent to the processing methods previously approved for the production of biodiesel from all categories of animal by-product raw materials. It is recommended to check the feasibility of the proposed HACCP plan by recording the main processing parameters for a certain time period under real industrial conditions.
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Chapman GE, Lockey R, Beck KE, Vickery C, Arnold M, Thorne L, Thorne JK, Walker SR, Keulen L, Casalone C, Griffiths PC, Simmons MM, Terry LA, Spiropoulos J. Inactivation of H‐type and L‐type bovine spongiform encephalopathy following recommended autoclave decontamination procedures. Transbound Emerg Dis 2020. [DOI: 10.1111/tbed.13513] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
| | | | - Katy E. Beck
- Animal and Plant Health Agency (APHA) Weybridge UK
| | | | - Mark Arnold
- Animal and Plant Health Agency (APHA) Weybridge UK
| | - Leigh Thorne
- Animal and Plant Health Agency (APHA) Weybridge UK
| | | | | | - Lucien Keulen
- Wageningen Bioveterinary Research Wageningen UR Lelystad The Netherlands
| | - Cristina Casalone
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta Sede Centrale di Torino Turin Italy
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Denys GA. Validation of the Bio-Response Solutions Human-28 Low-Temperature Alkaline Hydrolysis System. APPLIED BIOSAFETY 2019; 24:182-188. [DOI: 10.1177/1535676019871389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Gerald A. Denys
- Indiana University, Department of Pathology and Laboratory Medicine, University Hospital, School of Medicine, Indianapolis, IN, USA
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Williams K, Hughson AG, Chesebro B, Race B. Inactivation of chronic wasting disease prions using sodium hypochlorite. PLoS One 2019; 14:e0223659. [PMID: 31584997 PMCID: PMC6777796 DOI: 10.1371/journal.pone.0223659] [Citation(s) in RCA: 5] [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: 08/22/2019] [Accepted: 09/24/2019] [Indexed: 11/18/2022] Open
Abstract
Chronic wasting disease (CWD) is a fatal prion disease that can infect deer, elk and moose. CWD has now been detected in 26 states of the USA, 3 Canadian provinces, South Korea, Norway, Sweden and Finland. CWD continues to spread from endemic areas, and new foci of infections are frequently detected. As increasing numbers of cervids become infected, the likelihood for human exposure increases. To date, no cases of CWD infection in humans have been confirmed, but experience with the BSE zoonosis in the United Kingdom suggests exposure to CWD should be minimized. Specifically, hunters, meat processors and others in contact with tissues from potentially CWD-infected cervids need a practical method to decontaminate knives, saws and other equipment. Prions are notoriously difficult to inactivate, and most effective methods require chemicals or sterilization processes that are either dangerous, caustic, expensive or not readily available. Although corrosive, sodium hypochlorite (bleach) is widely available and affordable and has been shown to inactivate prion agents including those that cause scrapie, bovine spongiform encephalopathy and Creutzfeldt-Jakob disease. In the current study, we confirm that bleach is an effective disinfectant for CWD prions and establish minimum times and bleach concentrations to eliminate prion seeding activity from stainless steel and infected brain homogenate solutions. We found that a five-minute treatment with a 40% dilution of household bleach was effective at inactivating CWD seeding activity from stainless-steel wires and CWD-infected brain homogenates. However, bleach was not able to inactivate CWD seeding activity from solid tissues in our studies.
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Affiliation(s)
- Katie Williams
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Andrew G. Hughson
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Bruce Chesebro
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Brent Race
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
- * E-mail:
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Spiropoulos J, Lockey R, Beck KE, Vickery C, Holder TM, Thorne L, Arnold M, Andreoletti O, Simmons MM, Terry LA. Incomplete inactivation of atypical scrapie following recommended autoclave decontamination procedures. Transbound Emerg Dis 2019; 66:1993-2001. [PMID: 31111687 DOI: 10.1111/tbed.13247] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 03/21/2019] [Accepted: 05/16/2019] [Indexed: 11/28/2022]
Abstract
Prions are highly resistant to the decontamination procedures normally used to inactivate conventional pathogens. This is a challenging problem not only in the medical and veterinary fields for minimizing the risk of transmission from potentially infective sources but also for ensuring the safe disposal or subsequent use of animal by-products. Specific pressure autoclaving protocols were developed for this purpose, but different strains of prions have been reported to have differing resistance patterns to established prion decontamination procedures, and as additional TSE strains are identified it is necessary to determine the effectiveness of such procedures. In this study we assessed the efficacy of sterilization using the EU recommended autoclave procedure for prions (133°C, 3 Bar for 20 min) on the atypical or Nor98 (AS/Nor98) scrapie strain of sheep and goats. Using a highly sensitive murine mouse model (tg338) that overexpresses ovine PrPC , we determined that this method of decontamination reduced the infectivity titre by 1010 . Infectivity was nonetheless still detected after applying the recommended autoclaving protocol. This shows that AS/Nor98 can survive the designated legislative decontamination conditions, albeit with a significant decrease in titre. The infectivity of a classical scrapie isolate subjected to the same decontamination conditions was reduced by 106 suggesting that the AS/Nor98 isolate is less sensitive to decontamination than the classical scrapie source.
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Affiliation(s)
| | - Richard Lockey
- Animal and Plant Health Agency (APHA), Weybridge, Surrey, UK
| | - Katy E Beck
- Animal and Plant Health Agency (APHA), Weybridge, Surrey, UK
| | - Chris Vickery
- Animal and Plant Health Agency (APHA), Weybridge, Surrey, UK
| | - Thomas M Holder
- Animal and Plant Health Agency (APHA), Weybridge, Surrey, UK
| | - Leigh Thorne
- Animal and Plant Health Agency (APHA), Weybridge, Surrey, UK
| | - Mark Arnold
- Animal and Plant Health Agency (APHA), Weybridge, Surrey, UK
| | - Olivier Andreoletti
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | | | - Linda A Terry
- Animal and Plant Health Agency (APHA), Weybridge, Surrey, UK
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Smith A, Winter S, Lappin D, Sherriff A, McIvor I, Philp P, Suttner N, Holmes S, Stewart A. Reducing the risk of iatrogenic Creutzfeldt–Jakob disease by improving the cleaning of neurosurgical instruments. J Hosp Infect 2018. [DOI: 10.1016/j.jhin.2018.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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14
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Phan HTM, Bartz JC, Ayers J, Giasson BI, Schubert M, Rodenhausen KB, Kananizadeh N, Li Y, Bartelt-Hunt SL. Adsorption and decontamination of α-synuclein from medically and environmentally-relevant surfaces. Colloids Surf B Biointerfaces 2018; 166:98-107. [PMID: 29550546 PMCID: PMC5911191 DOI: 10.1016/j.colsurfb.2018.03.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 02/28/2018] [Accepted: 03/08/2018] [Indexed: 11/20/2022]
Abstract
The assembly and accumulation of α-synuclein fibrils are implicated in the development of several neurodegenerative disorders including multiple system atrophy and Parkinson's disease. Pre-existing α-synuclein fibrils can recruit and convert soluble non-fibrillar α-synuclein to the fibrillar form similar to what is observed in prion diseases. This raises concerns regarding attachment of fibrillary α-synuclein to medical instruments and subsequent exposure of patients to α-synuclein similar to what has been observed in iatrogenic transmission of prions. Here, we evaluated adsorption and desorption of α-synuclein to two surfaces: stainless steel and a gold surface coated with a 11-Amino-1-undecanethiol hydrochloride self-assembled-monolayer (SAM) using in-situ combinatorial quartz crystal microbalance with dissipation and spectroscopic ellipsometry. α-Synuclein was found to attach to both surfaces, however, increased α-synuclein adsorption was observed onto the positively charged SAM surface compared to the stainless steel surface. Dynamic light scattering data showed that larger α-synuclein fibrils were preferentially attached to the stainless steel surface when compared with the distributions in the original α-synuclein solution and on the SAM surface. We determined that after attachment, introduction of a 1N NaOH solution could completely remove α-synuclein adsorbed on the stainless steel surface while α-synuclein was retained on the SAM surface. Our results indicate α-synuclein can bind to multiple surface types and that decontamination is surface-dependent.
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Affiliation(s)
- Hanh T M Phan
- Department of Civil Engineering, University of Nebraska-Lincoln, United States; Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, United States
| | - Jason C Bartz
- Department of Medical Microbiology and Immunology, Creighton University, United States
| | - Jacob Ayers
- Department of Neuroscience, University of Florida, United States
| | - Benoit I Giasson
- Department of Neuroscience, University of Florida, United States
| | - Mathias Schubert
- Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, United States; Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, United States
| | - Keith B Rodenhausen
- Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, United States; Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, United States; Biolin Scientific, Inc., Paramus, NJ, United States
| | - Negin Kananizadeh
- Department of Civil Engineering, University of Nebraska-Lincoln, United States; Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, United States
| | - Yusong Li
- Department of Civil Engineering, University of Nebraska-Lincoln, United States
| | - Shannon L Bartelt-Hunt
- Department of Civil Engineering, University of Nebraska-Lincoln, United States; Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, United States.
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15
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Perić Kačarević Z, Kavehei F, Houshmand A, Franke J, Smeets R, Rimashevskiy D, Wenisch S, Schnettler R, Jung O, Barbeck M. Purification processes of xenogeneic bone substitutes and their impact on tissue reactions and regeneration. Int J Artif Organs 2018; 41:789-800. [PMID: 29707988 DOI: 10.1177/0391398818771530] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Xenogeneic bone substitute materials are widely used in oral implantology. Prior to their clinical use, purification of the former bone tissue has to be conducted to ensure the removal of immunogenic components and pathogens. Different physicochemical methods are applied for purification of the donor tissue, and temperature treatment is one of these methods. Differences in these methods and especially the application of different temperatures for purification may lead to different material characteristics, which may influence the tissue reactions to these materials and the related (bone) healing process. However, little is known about the different material characteristics and their influences on the healing process. Thus, the aim of this mini-review is to summarize the preparation processes and the related material characteristics, safety aspects, tissue reactions, resorbability and preclinical and clinical data of two widely used xenogeneic bone substitutes that mainly differ in the temperature treatment: sintered (cerabone®) and non-sintered (Bio-Oss®) bovine-bone materials. Based on the summarized data from the literature, a connection between the material-induced tissue reactions and the consequences for the healing processes are presented with the aim of translation into their clinical application.
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Affiliation(s)
- Zeljka Perić Kačarević
- 1 Department of Anatomy, Histology and Embryology, Faculty of Dental Medicine and Health, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia
| | - Faraz Kavehei
- 2 Department of Chemical Engineering, Imperial College London, London, UK
| | - Alireza Houshmand
- 3 Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Prosthodontics, Geriatric Dentistry and Craniomandibular Disorders, Berlin, Germany
| | - Jörg Franke
- 4 Department of Traumatology and Orthopedics, Elbe Kliniken Stade-Buxtehude, Stade, Germany
| | - Ralf Smeets
- 5 Department of Oral and Maxillofacial Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Denis Rimashevskiy
- 6 Department of Traumatology and Orthopedics, Peoples' Friendship University of Russia, Moscow, Russia
| | - Sabine Wenisch
- 7 Clinic of Small Animals, Institute of Veterinary Anatomy, Histology and Embryology, Justus Liebig University of Giessen, Giessen, Germany
| | | | - Ole Jung
- 5 Department of Oral and Maxillofacial Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Mike Barbeck
- 5 Department of Oral and Maxillofacial Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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17
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Transmission properties of atypical Creutzfeldt-Jakob disease: a clue to disease etiology? J Virol 2015; 89:3939-46. [PMID: 25609817 DOI: 10.1128/jvi.03183-14] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED The genotype at polymorphic codon 129 of the PRNP gene has a profound influence on both phenotypic expression and prion strain susceptibility in humans. For example, while the most common sporadic Creutzfeldt-Jakob disease (CJD) subtype, sporadic CJD-MM1 (M1 strain), induces a single phenotype after experimental transmission regardless of the codon 129 genotype of the recipient animal, the phenotype elicited by sporadic CJD-VV2 (V2 strain), the second most common subtype, varies according to the host codon 129 genotype. In particular, the propagation of the V2 strain in codon 129 methionine homozygotes has been linked only to acquired forms of CJD such as plaque-type dura mater graft-associated CJD (dCJD), a subgroup of iatrogenic CJD with distinctive phenotypic features, but has never been observed in sporadic CJD cases. In the present report, we describe atypical CJD cases carrying codon 129 methionine homozygosity, in a neurosurgeon and in a patient with a medical history of neurosurgery without dural grafting, showing the distinctive phenotypic features and transmission properties of plaque-type dCJD. These findings raise the possibility that the two cases, previously thought to represent sporadic CJD, might actually represent acquired CJD caused by infection with the V2 strain. Thus, careful analyses of phenotypic features and transmission properties in atypical cases may be useful to distinguish acquired from sporadic cases of CJD. IMPORTANCE Susceptibility to and phenotypic expression of Creutzfeldt-Jakob disease (CJD) depend on both the prion strain and genotype at polymorphic codon 129 of the PRNP gene. For example, propagation of the second most common sporadic CJD strain (V2 strain) into codon 129 methionine homozygotes has been linked to plaque-type dura mater graft-associated CJD (dCJD), a subgroup of iatrogenic CJD with distinctive phenotypic features, but has never been observed in sporadic CJD. In the present report, we describe atypical CJD cases in a neurosurgeon and in a patient with a medical history of neurosurgery without dural grafting, showing the distinctive phenotypic features and transmission properties of plaque-type dCJD. These findings raise the possibility that the two cases, previously considered to represent sporadic CJD, might actually represent acquired CJD caused by infection with the V2 strain.
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Bovine Spongiform Encephalopathy. Food Microbiol 2014. [DOI: 10.1128/9781555818463.ch25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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20
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Bellon A, Comoy E, Simoneau S, Mornac S, Dehen C, Perrin A, Arzel A, Arrabal S, Baron H, Laude H, You B, Deslys JP, Flan B. Decontamination of prions in a plasma product manufacturing environment. Transfusion 2014; 54:1028-36. [PMID: 24032663 DOI: 10.1111/trf.12381] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 07/08/2013] [Accepted: 07/09/2013] [Indexed: 12/12/2022]
Abstract
BACKGROUND The high resistance of prions to inactivating treatments requires the proper management of decontaminating procedures of equipment in contact with materials of human or animal origin destined for medical purposes. Sodium hydroxide (NaOH) is widely used today for this purpose as it inactivates a wide variety of pathogens including prions. STUDY DESIGN AND METHODS Several NaOH treatments were tested on prions bound to either stainless steel or chromatographic resins in industrial conditions with multiple prion strains. RESULTS Data show a strong correlation between inactivation results obtained by immunochemical detection of the prion protein and those obtained with infectivity assays and establish effective inactivation treatments for prions bound to stainless steel or chromatographic resins (ion exchange and affinity), including treatments with lower NaOH concentrations. Furthermore, no obvious strain-specific behavior difference was observed between experimental models. CONCLUSION The results generated by these investigations show that industrial NaOH decontamination regimens (in combination with the NaCl elution in the case of the chromatography process) attain substantial prion inactivation and/or removal between batches, thus providing added assurance to the biologic safety of the final plasma-derived medicinal products.
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Kobayashi A, Matsuura Y, Mohri S, Kitamoto T. Distinct origins of dura mater graft-associated Creutzfeldt-Jakob disease: past and future problems. Acta Neuropathol Commun 2014; 2:32. [PMID: 24685293 PMCID: PMC3976164 DOI: 10.1186/2051-5960-2-32] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 03/24/2014] [Indexed: 11/25/2022] Open
Abstract
Dura mater graft-associated Creutzfeldt-Jakob disease (dCJD) can be divided into two subgroups that exhibit distinct clinical and neuropathological features, with the majority represented by a non-plaque-type of dCJD (np-dCJD) and the minority by a plaque-type of dCJD (p-dCJD). The two distinct phenotypes of dCJD had been considered to be unrelated to the genotype (methionine, M or valine, V) at polymorphic codon 129 of the PRNP gene or type (type 1 or type 2) of abnormal isoform of prion protein (PrPSc) in the brain, while these are major determinants of clinicopathological phenotypes of sporadic CJD (sCJD). The reason for the existence of two distinct subgroups in dCJD had remained elusive. Recent progress in research of the pathogenesis of dCJD has revealed that two distinct subgroups of dCJD are caused by infection with different PrPSc strains from sCJD, i.e., np-dCJD caused by infection with sCJD-MM1/MV1, and p-dCJD caused by infection with sCJD-VV2 or -MV2. These studies have also revealed previously unrecognized problems as follows: (i) the numbers of p-dCJD patients may increase in the future, (ii) the potential risks of secondary infection from dCJD, particularly from p-dCJD, may be considerable, and (iii) the effectiveness of the current PrPSc decontamination procedures against the PrPSc from p-dCJD is uncertain. To prevent secondary infection from p-dCJD, the establishment of effective decontamination procedures is an urgent issue. In this review, we summarize the past and future problems surrounding dCJD.
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Affiliation(s)
- Atsushi Kobayashi
- Department of Neurological Science, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
| | - Yuichi Matsuura
- Influenza and Prion Disease Research Center, National Institute of Animal Health, Tsukuba, Ibaraki 305-0856, Japan
| | - Shirou Mohri
- Department of Neurological Science, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
| | - Tetsuyuki Kitamoto
- Department of Neurological Science, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
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22
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Ding N, Neumann NF, Price LM, Braithwaite SL, Balachandran A, Belosevic M, Gamal El-Din M. Ozone inactivation of infectious prions in rendering plant and municipal wastewaters. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 470-471:717-725. [PMID: 24184548 DOI: 10.1016/j.scitotenv.2013.09.099] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2013] [Revised: 09/21/2013] [Accepted: 09/29/2013] [Indexed: 06/02/2023]
Abstract
Disposal of tissues and organs associated with prion accumulation and infectivity in infected animals (designated as Specified Risk Materials [SRM]) is strictly regulated by the Canadian Food Inspection Agency (CFIA); however, the contamination of wastewater from slaughterhouses that handle SRM still poses public concern. In this study, we examined for the first time the partitioning of infectious prions in rendering plant wastewater and found that a large proportion of infectious prions were partitioned into the scum layer formed at the top after gravity separation, while quite a few infectious prions still remained in the wastewater. Subsequently, we assessed the ozone inactivation of infectious prions in the raw, natural gravity-separated and dissolved air flotation (DAF)-treated (i.e., primary-treated) rendering plant wastewater, and in a municipal final effluent (i.e., secondary-treated municipal wastewater). At applied ozone doses of 43.4-44.6 mg/L, ozone was instantaneously depleted in the raw rendering plant wastewater, while a greater than 4-log10 inactivation was achieved at a 5 min exposure in the DAF-treated rendering plant wastewater. Prion inactivation in the municipal final effluent was conducted with two levels of applied ozone doses of 13.4 and 22.5mg/L, and a greater than 4-log10 inactivation was achieved at a 5 min exposure with the higher ozone dose. Efficiency factor Hom (EFH) models were used to model (i.e., fit) the experimental data. The CT (disinfectant concentration multiplied by contact time) values were determined for 2- and 3-log10 inactivation in the municipal final effluent treated with an ozone dose of 13.4 mg/L. Our results indicate that ozone could serve as a final barrier for prion inactivation in primary- and/or secondary-treated wastewaters.
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Affiliation(s)
- Ning Ding
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta, Canada
| | - Norman F Neumann
- Department of Public Health Sciences, University of Alberta, Edmonton, Alberta, Canada; Provincial Laboratory for Public Health, Edmonton, Alberta, Canada
| | - Luke M Price
- Department of Public Health Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Shannon L Braithwaite
- Department of Public Health Sciences, University of Alberta, Edmonton, Alberta, Canada
| | | | - Miodrag Belosevic
- Department of Public Health Sciences, University of Alberta, Edmonton, Alberta, Canada; Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Mohamed Gamal El-Din
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta, Canada.
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23
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Affiliation(s)
- V. Beringue
- UR892 Virologie et Immunologie Moléculaires Centre de Recherche de Jouy-en-Josas F-78352 Jouy-en-Josas, France
| | - O. Andreoletti
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles 31076 Toulouse, France
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Smith JD, Nicholson EM, Greenlee JJ. Evaluation of a combinatorial approach to prion inactivation using an oxidizing agent, SDS, and proteinase K. BMC Vet Res 2013; 9:151. [PMID: 23886483 PMCID: PMC3728008 DOI: 10.1186/1746-6148-9-151] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Accepted: 07/24/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Prions demonstrate an unusual resistance to methods effective at inactivating conventional microorganisms. This has resulted in a very tangible and difficult infection control challenge to the medical and veterinary communities, as well as animal agriculture and related industries. Currently accepted practices of harsh chemical treatments such as prolonged exposure to sodium hydroxide or sodium hypochlorite, or autoclaving are not suitable in many situations. Less caustic and more readily applicable treatments to contaminated environments are therefore desirable. We recently demonstrated that exposure of the RML scrapie agent to a commercial product containing sodium percarbonate (SPC-P) with or without sodium dodecyl sulfate (SDS) rendered PrP(Sc) sensitive to proteinase K (PK), but did not eliminate infectivity. The current study was designed to evaluate the efficacy of a combinatorial approach to inactivating prions by exposing RML-positive brain homogenate to SPC-P and SDS followed by PK. Treated samples were evaluated for PrP(Sc)-immunoreactivity by western blot, and residual infectivity by mouse bioassay. RESULTS Treatment of infected brain homogenate with SPC-P and SDS followed by PK exposure resulted in a 4-5 log10 reduction in infectivity when bioassayed in tga20 mice. CONCLUSIONS This study demonstrates that exposure of the RML scrapie agent to SPC-P and SDS followed by PK markedly reduces, but does not eliminate infectivity. The results of this study encourage further investigation into whether consecutive or concomitant exposure to sodium percarbonate, SDS, and a protease may serve as a viable and non-caustic option for prion inactivation.
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Affiliation(s)
- Jodi D Smith
- Virus and Prion Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, 1920 Dayton Ave, Ames, IA 50010, USA
- Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
| | - Eric M Nicholson
- Virus and Prion Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, 1920 Dayton Ave, Ames, IA 50010, USA
| | - Justin J Greenlee
- Virus and Prion Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, 1920 Dayton Ave, Ames, IA 50010, USA
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Okoroma EA, Purchase D, Garelick H, Morris R, Neale MH, Windl O, Abiola OO. Enzymatic formulation capable of degrading scrapie prion under mild digestion conditions. PLoS One 2013; 8:e68099. [PMID: 23874511 PMCID: PMC3712960 DOI: 10.1371/journal.pone.0068099] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 05/24/2013] [Indexed: 12/01/2022] Open
Abstract
The prion agent is notoriously resistant to common proteases and conventional sterilisation procedures. The current methods known to destroy prion infectivity such as incineration, alkaline and thermal hydrolysis are harsh, destructive, environmentally polluting and potentially hazardous, thus limit their applications for decontamination of delicate medical and laboratory devices, remediation of prion contaminated environment and for processing animal by-products including specified risk materials and carcases. Therefore, an environmentally friendly, non-destructive enzymatic degradation approach is highly desirable. A feather-degrading Bacillus licheniformis N22 keratinase has been isolated which degraded scrapie prion to undetectable level of PrPSc signals as determined by Western Blot analysis. Prion infectivity was verified by ex vivo cell-based assay. An enzymatic formulation combining N22 keratinase and biosurfactant derived from Pseudomonas aeruginosa degraded PrPSc at 65°C in 10 min to undetectable level -. A time-course degradation analysis carried out at 50°C over 2 h revealed the progressive attenuation of PrPSc intensity. Test of residual infectivity by standard cell culture assay confirmed that the enzymatic formulation reduced PrPSc infectivity to undetectable levels as compared to cells challenged with untreated standard scrapie sheep prion (SSBP/1) (p-value = 0.008 at 95% confidence interval). This novel enzymatic formulation has significant potential application for prion decontamination in various environmentally friendly systems under mild treatment conditions.
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Affiliation(s)
- Emeka A. Okoroma
- Department of Natural Sciences, School of Science and Technology, Middlesex University, London, United Kingdom
| | - Diane Purchase
- Department of Natural Sciences, School of Science and Technology, Middlesex University, London, United Kingdom
- * E-mail:
| | - Hemda Garelick
- Department of Natural Sciences, School of Science and Technology, Middlesex University, London, United Kingdom
| | - Roger Morris
- School of Biomedical Sciences, King’s College London, London, United Kingdom
| | - Michael H. Neale
- Animal Health and Veterinary Laboratories Agency (AHVLA), Surrey, United Kingdom
| | - Otto Windl
- Animal Health and Veterinary Laboratories Agency (AHVLA), Surrey, United Kingdom
| | - Oduola O. Abiola
- PAP Rashidah Sa’adatul Bolkiah Institute of Health Sciences, Universiti Brunei Darussalam, Gadong, Brunei Darussalam
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Ding N, Neumann NF, Price LM, Braithwaite SL, Balachandran A, Mitchell G, Belosevic M, Gamal El-Din M. Kinetics of ozone inactivation of infectious prion protein. Appl Environ Microbiol 2013; 79:2721-30. [PMID: 23416994 PMCID: PMC3623189 DOI: 10.1128/aem.03698-12] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Accepted: 02/06/2013] [Indexed: 01/20/2023] Open
Abstract
The kinetics of ozone inactivation of infectious prion protein (PrP(Sc), scrapie 263K) was investigated in ozone-demand-free phosphate-buffered saline (PBS). Diluted infectious brain homogenates (IBH) (0.01%) were exposed to a predetermined ozone dose (10.8 ± 2.0 mg/liter) at three pHs (pH 4.4, 6.0, and 8.0) and two temperatures (4°C and 20°C). The inactivation of PrP(Sc) was quantified by determining the in vitro destruction of PrP(Sc) templating properties using the protein misfolding cyclic amplification (PMCA) assay and bioassay, which were shown to correlate well. The inactivation kinetics were characterized by both Chick-Watson (CW) and efficiency factor Hom (EFH) models. It was found that the EFH model fit the experimental data more appropriately. The efficacy of ozone inactivation of PrP(Sc) was both pH and temperature dependent. Based on the EFH model, CT (disinfectant concentration multiplied by contact time) values were determined for 2-log10, 3-log10, and 4-log10 inactivation at the conditions under which they were achieved. Our results indicated that ozone is effective for prion inactivation in ozone-demand-free water and may be applied for the inactivation of infectious prion in prion-contaminated water and wastewater.
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Affiliation(s)
- Ning Ding
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta, Canada
| | - Norman F. Neumann
- Department of Public Health Sciences, University of Alberta, Edmonton, Alberta, Canada
- Provincial Laboratory for Public Health, Edmonton, Alberta, Canada
| | - Luke M. Price
- Department of Public Health Sciences, University of Alberta, Edmonton, Alberta, Canada
| | | | | | | | - Miodrag Belosevic
- Department of Public Health Sciences, University of Alberta, Edmonton, Alberta, Canada
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Mohamed Gamal El-Din
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta, Canada
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27
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Matsuura Y, Ishikawa Y, Bo X, Murayama Y, Yokoyama T, Somerville RA, Kitamoto T, Mohri S. Quantitative analysis of wet-heat inactivation in bovine spongiform encephalopathy. Biochem Biophys Res Commun 2013; 432:86-91. [DOI: 10.1016/j.bbrc.2013.01.081] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Accepted: 01/12/2013] [Indexed: 01/30/2023]
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Bi L, Li DC, Huang ZS, Yuan Z. Effects of sodium hydroxide, sodium hypochlorite, and gaseous hydrogen peroxide on the natural properties of cancellous bone. Artif Organs 2013; 37:629-36. [PMID: 23373516 DOI: 10.1111/aor.12048] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Processed xenegeneic cancellous bone represents an alternative to bone autograft. In order to observe the effects of present prion inactivation treatments on the natural properties of xenogeneic cancellous bones, we treated bovine bone granules with sodium hydroxide (NaOH), sodium hypochlorite (NaOCl), and gaseous hydrogen peroxide (gH2 O2 ) respectively in this study. The microstructure, composition, and mineral content of the granules were evaluated by scanning electron micrograph, energy dispersive X-ray spectroscopy, ash analysis, and micro-computed tomography. The biomechanical property was analyzed by a materials testing machine. The cytocompatibility was evaluated by using a mouse fibroblast cell line (3T3). The microstructure, organic content, and mechanical strength were dramatically altered at the surface of bone in both NaOH- and NaOCl-treated groups, but not in the gH2 O2 -treated group. Compared with the gH2 O2 -treated group, attachment and proliferation of 3T3 were reduced in either NaOH- or NaOCl-treated groups. As the consequence, gH2 O2 treatment may be a useful approach of disinfection for the preparation of natural cancellous bone with well-preserved structural, mechanical, and biological properties.
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Affiliation(s)
- Long Bi
- Department of Orthopaedics, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
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29
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Smith JD, Nicholson EM, Foster GH, Greenlee JJ. Exposure of RML scrapie agent to a sodium percarbonate-based product and sodium dodecyl sulfate renders PrPSc protease sensitive but does not eliminate infectivity. BMC Vet Res 2013; 9:8. [PMID: 23311930 PMCID: PMC3599183 DOI: 10.1186/1746-6148-9-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Accepted: 01/08/2013] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Prions, the causative agents of the transmissible spongiform encephalopathies, are notoriously difficult to inactivate. Current decontamination recommendations by the World Health Organization include prolonged exposure to 1 N sodium hydroxide or > 20,000 ppm sodium hypochlorite, or autoclaving. For decontamination of large stainless steel surfaces and equipment as in abattoirs, for example, these methods are harsh or unsuitable. The current study was designed to evaluate the effectiveness of a commercial product containing sodium percarbonate to inactivate prions. Samples of mouse brain infected with a mouse-adapted strain of the scrapie agent (RML) were exposed to a sodium percarbonate-based product (SPC-P). Treated samples were evaluated for abnormal prion protein (PrPSc)-immunoreactivity by western blot analysis, and residual infectivity by mouse bioassay. RESULTS Exposure to a 21% solution of SPC-P or a solution containing either 2.1% or 21% SPC-P in combination with sodium dodecyl sulfate (SDS) resulted in increased proteinase K sensitivity of PrPSc. Limited reductions in infectivity were observed depending on treatment condition. A marginal effect on infectivity was observed with SPC-P alone, but an approximate 2-3 log10 reduction was observed with the addition of SDS, though exposure to SDS alone resulted in an approximate 2 log10 reduction. CONCLUSIONS This study demonstrates that exposure of a mouse-adapted scrapie strain to SPC-P does not eliminate infectivity, but does render PrPSc protease sensitive.
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Affiliation(s)
- Jodi D Smith
- Virus and Prion Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, 1920 Dayton Ave, Ames, IA 50010, USA
| | - Eric M Nicholson
- Virus and Prion Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, 1920 Dayton Ave, Ames, IA 50010, USA
| | - Gregory H Foster
- Virus and Prion Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, 1920 Dayton Ave, Ames, IA 50010, USA
| | - Justin J Greenlee
- Virus and Prion Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, 1920 Dayton Ave, Ames, IA 50010, USA
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Simpson DA, Masters CL, Ohlrich G, Purdie G, Stuart G, Tannenberg AE. Iatrogenic Creutzfeldt-Jakob disease and its neurosurgical implications. J Clin Neurosci 2012; 3:118-23. [PMID: 18638852 DOI: 10.1016/s0967-5868(96)90003-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/1995] [Accepted: 10/06/1995] [Indexed: 11/28/2022]
Abstract
Creutzfeldt-Jakob (CJD) disease has been reported after the insertion of dural homografts. Two Australian cases of CJD, both following posterior fossa craniotomies done in 1982, are reported; the incubation periods were 5 and 12 years. It seems highly probable that the association is causal. CJD infective agents (prions) are resistant to many previously accepted means of sterilisation and it is postulated that cadaver dural material was either derived from subjects with CID, or was contaminated during preparation. In Australia the use of dural homografts in neurosurgery was abandoned in 1987; as the mean incubation period (determined from a world-wide review) has been about 65 months, it is now hoped that this cause of CJD will not recur in the Australian population, although it is premature to state this with confidence. However, precautions against case-to-case transmission remain necessary, and guidelines for this purpose should be enforced in theatre practice and in organ donations.
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Affiliation(s)
- D A Simpson
- Department of Neurosurgery, Women's and Children's Hospital, Adelaide, Australia
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Smith JD, Greenlee JJ, Foster GH, Nicholson EM. Acetone precipitation of the scrapie agent results in successful recovery of PrP(Sc) but decreased infectivity. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2012; 60:4758-4762. [PMID: 22519670 DOI: 10.1021/jf300639h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Bioassay is considered the most sensitive method for evaluating prion inactivation procedures. Because prions are resistant to methods effective at inactivating conventional microorganisms, prion inactivation research has focused on relatively harsh alternatives, such as concentrated sodium hypochlorite or sodium hydroxide. Often, bioassay for residual infectivity in these studies requires dilution or biochemical alteration of the treated sample in order to maintain subject health and survival. Ideally, prions from treated samples could be sufficiently separated from the inactivating agent without alteration of the sample and with negligible loss of infectivity prior to inoculation into the bioassay host. The current study was designed to evaluate acetone precipitation of the disease-associated form of the prion protein (PrP(Sc)) from brain homogenate derived from mice with the RML (Rocky Mountain Laboratory) strain of scrapie. The ability to recover PrP(Sc) was evaluated by Western blot. Dilutions of acetone-precipitated RML-positive brain homogenate were compared to nonprecipitated RML homogenate, resulting in similar PrP(Sc) detection levels down to 0.025 mg equivalents of brain tissue. The impact of the method on infectivity was investigated by bioassay in intracranially inoculated tga20 mice. Additionally, contributions to infectivity from the pellet and supernatant fractions were investigated. Acetone precipitation resulted in a 1-log₁₀ reduction in infectivity. Infectivity could not be reconstituted by the acetone soluble fraction of the infectious sample or uninfected brain. This study demonstrates that PrP(Sc) can successfully be precipitated out of infected brain homogenate using acetone but that there is a reduction in infectivity attributable to the procedure that would need to be considered when evaluating bioassay results.
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Affiliation(s)
- J D Smith
- Virus and Prion Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, Ames, Iowa, USA
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Inactivation of template-directed misfolding of infectious prion protein by ozone. Appl Environ Microbiol 2011; 78:613-20. [PMID: 22138993 DOI: 10.1128/aem.06791-11] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Misfolded prions (PrP(Sc)) are well known for their resistance to conventional decontamination processes. The potential risk of contamination of the water environment, as a result of disposal of specified risk materials (SRM), has raised public concerns. Ozone is commonly utilized in the water industry for inactivation of microbial contaminants and was tested in this study for its ability to inactivate prions (263K hamster scrapie = PrP(Sc)). Treatment variables included initial ozone dose (7.6 to 25.7 mg/liter), contact time (5 s and 5 min), temperature (4°C and 20°C), and pH (pH 4.4, 6.0, and 8.0). Exposure of dilute suspensions of the infected 263K hamster brain homogenates (IBH) (0.01%) to ozone resulted in the in vitro destruction of the templating properties of PrP(Sc), as measured by the protein misfolding cyclic amplification (PMCA) assay. The highest levels of prion inactivation (≥4 log(10)) were observed with ozone doses of 13.0 mg/liter, at pH 4.4 and 20°C, resulting in a CT (the product of residual ozone concentration and contact time) value as low as 0.59 mg · liter(-1) min. A comparison of ozone CT requirements among various pathogens suggests that prions are more susceptible to ozone degradation than some model bacteria and protozoa and that ozone treatment may be an effective solution for inactivating prions in water and wastewater.
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Fernie K, Hamilton S, Somerville RA. Limited efficacy of steam sterilization to inactivate vCJD infectivity. J Hosp Infect 2011; 80:46-51. [PMID: 22099953 DOI: 10.1016/j.jhin.2011.09.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Accepted: 09/16/2011] [Indexed: 10/15/2022]
Abstract
BACKGROUND The transmission of bovine spongiform encephalopathy (BSE) to humans as variant Creutzfeldt-Jakob Disease (vCJD) raised concerns about potential secondary transmissions due to the resistance of the agents causing transmissible spongiform encephalopathies (TSEs), sometimes known as prions, to commonly used methods of sterilization, notably steam sterilization (or autoclaving). It has been suggested that surgical instruments and other medical devices might retain sufficient infected tissue debris after cleaning and steam sterilization to infect patients on whom they are subsequently used. AIM To determine whether concerns about the lack of efficacy of steam sterilization of vCJD were justified. METHODS The reduction in infectivity of brain macerates of vCJD brain after steam sterilization using the standard temperatures and time recommended for autoclaving in UK hospitals (134-137°C for 3 min) was measured. FINDINGS Reductions in titre of 10(2.3) to >10(3.6) ID(50) were found. In three of four samples, infectivity was recovered after steam sterilization. CONCLUSION As noted previously, TSE strains derived from BSE sources appear to be more resistant to steam sterilization and other forms of heat inactivation than other TSE sources.
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Affiliation(s)
- K Fernie
- Neurobiology Division, The Roslin Institute and R(D)SVS, University of Edinburgh, Easter Bush, Midlothian, UK
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Takeuchi A, Komiya M, Kitamoto T, Morita M. Deduction of the evaluation limit and termination timing of multi-round protein misfolding cyclic amplification from a titration curve. Microbiol Immunol 2011; 55:502-9. [PMID: 21443616 DOI: 10.1111/j.1348-0421.2011.00340.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
In this study, the efficacy of disinfectants in reducing the partially protease-resistant isoform of prion protein was evaluated by a multi-round protein misfolding cyclic amplification (PMCA) technique. Hamster brains infected with scrapie-derived strain 263K were homogenized, treated under inactivating or mock conditions, and subjected to multi-round PMCA. Four sets of serial 10-fold dilutions of mock-treated samples were analyzed. Although considerable variability was observed in the signal patterns, between the second and sixth rounds the number of the PMCA round correlated in a linear fashion with the mean dilution factor of mock-treated, infected brains, corresponding to a log reduction factor (LRF) of 3.8-7.3 log. No signals were observed in the PMCA products amplified from normal hamster brain homogenates. The mean numbers of rounds at the first appearance of the signal for 1 M and 2 M NaOH-treated samples were 4.33 and 4, respectively. Using the linear regression line as the titration curve, the LRFs of these disinfectants were found to be 6.1 and 5.8 log, respectively; these values were not significantly different. The mean number of rounds for the alkaline cleaner and sodium dodecyl sulfate were 9 and 10.33, respectively, and were outside the range of both the linear regression line and evaluation limit. The disinfectants were considered very effective because their LRFs were ≥7.3 log. These estimations were concordant with previous bioassay-based reports. Thus, the evaluation limit seems to be valuable in some applications of multi-round PMCA, such as disinfectant assessment and process validation.
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Affiliation(s)
- Atsuko Takeuchi
- Department of Neurological Science, Tohoku University Graduate School of Medicine, Japan
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Abstract
Over the past year, several situations have occurred in Canada in which patients who had recently undergone a surgical procedure were subsequently diagnosed with confirmed or suspected Creutzfeldt-Jakob disease (CJD). This raised concerns over contamination of surgical instruments: which instruments might have been contaminated from direct exposure to tissues; can instruments become cross-contaminated by exposure to other contaminated instruments; what assessment is necessary to determine cross-contamination; and what should be done with instruments that have been contaminated. Additionally, should there be a patient traceback in the face of potential but unproven exposure? Unfortunately, there are no easy answers to most of the above questions. Australia, the United Kingdom and the World Health Organization have developed guidelines for the infection control management of patients with CJD, as well as instruments and devices that come into contact with them and their tissues (1-3). Health Canada's draft CJD infection control guidelines, withdrawn from the Health Canada Web site until safety concerns regarding sodium hydroxide can be addressed, closely mirrored recommendations made in those documents. The Centers for Disease Control and Prevention guidelines for CJD are under revision. However, a recent American publication made recommendations on what procedures should be used for reprocessing items that have been in contact with the prion protein (PrP) (4). These recommendations differ substantially from the draft Canadian guidelines. This article reviews current knowledge about CJD, and highlights some of the infection control concerns and controversies.
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Somerville RA, Gentles N. Characterization of the effect of heat on agent strains of the transmissible spongiform encephalopathies. J Gen Virol 2011; 92:1738-1748. [PMID: 21471321 DOI: 10.1099/vir.0.030452-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The causal agents of the transmissible spongiform encephalopathy (TSE) diseases, sometimes called prion diseases, are characterized by high resistance to inactivation with heat. Results from thermal inactivation experiments on nine TSE strains, seven passaged in two PrP genotypes, showed differences in sensitivity to heat inactivation ranging over 17 °C. In addition, the rate of inactivation with increasing temperature varied between TSE models. In some cases passage in an alternative PrP genotype had little effect on the resulting inactivation properties, but for others the infectious agent was inactivated at lower temperatures. No strain with higher thermostability properties was selected. The effect of mixing two TSE strains, to see whether their properties were affected through interaction with each other, was also examined. The results showed that both strains behaved as expected from the behaviour of the unmixed controls, and that the strain responsible for inducing TSE disease could be identified. There was no evidence of a direct effect on intrinsic strain properties. Overall, the results illustrate the diversity in properties of TSE strains. They require intrinsic molecular properties of TSE agents to accommodate high resistance to inactivation and a mechanism, independent of the host, to directly encode these differences. These findings are more readily reconciled with models of TSE agents with two separate components, one of which is independent of the host and comprises a TSE-specific nucleic acid, than with models based solely on conformational changes to a host protein.
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Affiliation(s)
- Robert A Somerville
- Neuropathogenesis Division, The Roslin Institute and Royal (Dick) Veterinary School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian, EH25 9PS, Scotland, UK
| | - Nicola Gentles
- Neuropathogenesis Division, The Roslin Institute and Royal (Dick) Veterinary School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian, EH25 9PS, Scotland, UK
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Scientific Opinion on the revision of the quantitative risk assessment (QRA) of the BSE risk posed by processed animal proteins (PAPs). EFSA J 2011. [DOI: 10.2903/j.efsa.2011.1947] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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The cleaning of photographic retractors; a survey, clinical and laboratory study. Br Dent J 2010; 208:E14; discussion 306-7. [PMID: 20357820 DOI: 10.1038/sj.bdj.2010.310] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/24/2009] [Indexed: 11/09/2022]
Abstract
OBJECTIVES To determine the methods currently being used to decontaminate photographic retractors in specialist orthodontic practice and to investigate the effectiveness of the cleaning methods. DESIGN The study was carried out in two parts: I - a postal self-report questionnaire, and II - a cross-sectional clinical and laboratory investigation. SETTING The Orthodontic Department of the Charles Clifford Dental Hospital. SUBJECTS AND MATERIALS I - The questionnaire was sent to 278 specialist UK orthodontists. II - One hundred and twenty pairs of photographic retractors were collected following use. One retractor from each pair was randomly chosen to be the unwashed control and immediately placed in 20 ml of PBS-Tween for elution. The other was subjected to the one of four cleaning procedures: alcohol wipe, handwashing, ultrasonic bath or washer-disinfector, before being placed in PBS-Tween. Aliquots were taken for assay. MAIN OUTCOME MEASURES Antibody capture (ELISA) for amylase, to detect the presence of saliva, and for albumin, to detect the presence of serum. RESULTS I - The questionnaire response rate was 65% and the majority of respondents (87.2%) were routinely taking clinical photographs. A wide variety of techniques were being used to decontaminate photographic retractors. II - All unwashed controls had detectable levels of amylase and albumin. All the retractors that were cleaned using an alcohol wipe had residual detectable levels of amylase and 80% had detectable levels of albumin. Only one retractor had detectable amylase and one had detectable albumin following cleaning using the washer-disinfector. There was a highly significant statistical difference between the techniques in the proportional reduction in both amylase and albumin detected from the unwashed control and cleaned experimental retractors (p <0.001). The infective risk from inadequate cleaning of photographic retractors is discussed. CONCLUSIONS The washer-disinfector is the most effective method of cleaning photographic retractors, but no method was found to be 100% successful at removing amylase and albumin.
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Rutala WA, Weber DJ. Guideline for disinfection and sterilization of prion-contaminated medical instruments. Infect Control Hosp Epidemiol 2010; 31:107-17. [PMID: 20055640 DOI: 10.1086/650197] [Citation(s) in RCA: 117] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- William A Rutala
- Hospital Epidemiology, University of North Carolina School of Medicine, Chapel Hill, 27599-7030, USA.
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40
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Prion protein detection via direct immuno-quantitative real-time PCR. J Microbiol Methods 2009; 78:307-11. [DOI: 10.1016/j.mimet.2009.07.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2009] [Revised: 07/02/2009] [Accepted: 07/02/2009] [Indexed: 11/30/2022]
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Arnold ME, Hawkins SAC, Green R, Dexter I, Wells GAH. Pathogenesis of experimental bovine spongiform encephalopathy (BSE): estimation of tissue infectivity according to incubation period. Vet Res 2009; 40:8. [PMID: 18950589 PMCID: PMC2695012 DOI: 10.1051/vetres:2008046] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2008] [Accepted: 10/23/2008] [Indexed: 11/14/2022] Open
Abstract
This paper reports the results of tissue infectivity assays of bovine spongiform encephalopathy (BSE) agent in orally exposed cattle at stages during the incubation period. Estimations of the titre of infectivity in central nervous system (CNS), certain peripheral nerve ganglia and distal ileum tissue were made according to time post exposure from the relationship between incubation period and dose for RIII mice and C57bl mice using data from titrations of brain material from cases of BSE. The rate of increase of infectivity in the bovine CNS was then estimated, taking into account these tissue infectivity titres, the variability of the brain titre of clinical field cases of BSE, and the probability density of the expected number of months before clinical onset of each infected bovine. The doubling time for CNS was shown to equal 1.2 months. The titre in the thoracic dorsal root ganglia (DRG) was, on average, approximately 1 log units less than CNS, and cervical DRG approximately 0.5 log less than thoracic DRG. The pattern of increase of infectivity in the distal ileum is that of an initial increase up to 14-18 months post exposure, followed by a decrease, which is likely to be highly variable between animals. These results will be informative for future risk assessments of BSE, especially in relation to reviewing current control measures.
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Affiliation(s)
- Mark Edward Arnold
- Veterinary Laboratories Agency, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, United Kingdom.
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Seeger H, Julius C, Cozzari C, Calella AM, Dattilo M, Aguzzi A. Prion depletion and preservation of biological activity by preparative chaotrope ultracentrifugation. Biologicals 2008; 36:403-11. [PMID: 18760936 DOI: 10.1016/j.biologicals.2008.07.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2007] [Revised: 06/26/2008] [Accepted: 07/16/2008] [Indexed: 10/21/2022] Open
Abstract
Prions are characterized by unusual physicochemical properties, such as insolubility and resistance to proteases, and maintain infectivity after contact with disinfectants and decontamination procedures active against conventional pathogens. To date, most methods for prion inactivation are either incomplete or unacceptably harsh for the purification of fragile biotherapeutics. Here we describe a simple prion removal procedure that takes advantage of differential sedimentation and denaturation of prions. Prion-spiked fluids were layered onto an intermediate sucrose cushion and an 8M urea solution, and subjected to single-step ultracentrifugation. Due to their insolubility, prions rapidly traveled through the sucrose cushion into the urea solution. Prion infectivity in the upper phase was reduced by at least 3.2 logs, or up to 6 logs or more. Very little soluble protein was lost from the input sample and a proof-of-principle experiment demonstrated only marginally reduced biological activity of spiked enzyme after ultracentrifugation. This procedure is likely to synergize with nanofiltration and other prion removal steps in the treatment of batches of raw and semifinal biopharmaceutical materials.
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Affiliation(s)
- Harald Seeger
- Institute of Neuropathology, University Hospital of Zürich, Schmelzbergstrasse 12, CH-8091 Zürich, Switzerland.
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Müller H, Stitz L, Riesner D. Prion decontamination during the oleochemical process of fat hydrogenation. EUR J LIPID SCI TECH 2008. [DOI: 10.1002/ejlt.200700171] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Henrik Müller
- Institut für Physikalische Biologie, Heinrich‐Heine‐Universität Düsseldorf, Düsseldorf, Germany
| | - Lothar Stitz
- Institut für Immunologie, Friedrich‐Loeffler‐Institut (FLI), Bundesforschungsinstitut für Tiergesundheit, Tübingen, Germany
| | - Detlev Riesner
- Institut für Physikalische Biologie, Heinrich‐Heine‐Universität Düsseldorf, Düsseldorf, Germany
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Lemmer K, Mielke M, Kratzel C, Joncic M, Oezel M, Pauli G, Beekes M. Decontamination of surgical instruments from prions. II. In vivo findings with a model system for testing the removal of scrapie infectivity from steel surfaces. J Gen Virol 2008; 89:348-358. [PMID: 18089760 DOI: 10.1099/vir.0.83396-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The unusual resistance of agents causing transmissible spongiform encephalopathies (TSEs) to chemical or thermal inactivation requires special decontamination procedures in order to prevent accidental transmission of these pathogens by surgical instruments. In the search for effective, instrument-compatible and routinely applicable decontamination procedures, a previous study [Lemmer, K., Mielke, M., Pauli, G. & Beekes, M. (2004). J Gen Virol 85, 3805-3816] identified promising reagents in an in vitro carrier assay using steel wires contaminated with the disease-associated prion protein, PrP(Sc). In the follow-up study presented here, these reagents were validated for their decontamination potential in vivo. Steel wires initially loaded with >or=3 x 10(5) LD(50) of 263K scrapie infectivity were implanted into the brains of hamsters after treatment for decontamination and subsequently monitored for their potential to trigger clinical disease or subclinical cerebral PrP(Sc) deposition within an observation period of 500 days. It was found that routinely usable reagents such as a commercially available alkaline cleaner (pH 12.2) applied for 1 h at 23 degrees C or for 10 min at 55 degrees C and a mixture of 0.2 % SDS and 0.3 % NaOH (pH 12.8) applied for 5 or 10 min at 23 degrees C achieved removal of 263K scrapie infectivity below the threshold of detection (titre reduction of >or=5.5 log(10) units). The increasing use during the past few years of similar model systems by different research groups will facilitate comparison and integration of findings on the decontamination of steel surfaces from prions. Methods identified as highly effective in the 263K steel wire model need to be validated for human TSE agents on different types of instrument surfaces.
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Affiliation(s)
- Karin Lemmer
- P24, Transmissible Spongiform Encephalopathies, Robert Koch-Institut, Nordufer 20, 13353 Berlin, Germany
| | - Martin Mielke
- FG 14, Applied Infection Control and Hospital Hygiene, Robert Koch-Institut, Nordufer 20, 13353 Berlin, Germany
| | - Christine Kratzel
- P24, Transmissible Spongiform Encephalopathies, Robert Koch-Institut, Nordufer 20, 13353 Berlin, Germany
| | - Marion Joncic
- P24, Transmissible Spongiform Encephalopathies, Robert Koch-Institut, Nordufer 20, 13353 Berlin, Germany
| | - Muhsin Oezel
- ZBS4, Centre for Biological Safety - Imaging Techniques for Rapid Morphology-Based Diagnostics of Infectious Organisms, Robert Koch-Institut, Nordufer 20, 13353 Berlin, Germany
| | - Georg Pauli
- ZBS1, Centre for Biological Safety - Highly Pathogenic Viruses, Robert Koch-Institut, Nordufer 20, 13353 Berlin, Germany
| | - Michael Beekes
- P24, Transmissible Spongiform Encephalopathies, Robert Koch-Institut, Nordufer 20, 13353 Berlin, Germany
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Kelly TAN, Fisher MB, Oswald ES, Tai T, Mauck RL, Ateshian GA, Hung CT. Low-serum media and dynamic deformational loading in tissue engineering of articular cartilage. Ann Biomed Eng 2008; 36:769-79. [PMID: 18299986 DOI: 10.1007/s10439-008-9476-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2007] [Accepted: 02/15/2008] [Indexed: 11/28/2022]
Abstract
High-serum media have been shown to produce significant improvement in the properties of tissue-engineered articular cartilage when applied in combination with dynamic deformational loading. To mitigate concerns regarding the culture variability introduced by serum, we examined the interplay between low-serum/ITS-supplemented media and dynamic deformational loading. Our results show that low serum/ITS supplementation does not support the same level of tissue formation as compared to high serum controls. In free-swelling culture, using a combination of ITS with concentrations of FBS above 2% negated the beneficial effects of ITS. Although there were beneficial effects with loading and 0.2%FBS + ITS, these constructs significantly underperformed relative to 20%FBS constructs. At 2%FBS + ITS, the free-swelling construct stiffness and composition approached or exceeded that of 20%FBS constructs. With dynamic loading, the properties of 2%FBS + ITS constructs were significantly lower than free-swelling controls and 20%FBS constructs by day 42. By priming the chondrocytes in 20%FBS prior to exposure to low-serum/ITS media, we observed that low-serum/ITS media produced significant enhancement in tissue properties compared to constructs grown continuously in 20%FBS.
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Affiliation(s)
- Terri-Ann N Kelly
- Cellular Engineering Laboratory, Department of Biomedical Engineering, Columbia University, 351 Engineering Terrace, MC 8904, 1210 Amsterdam Avenue, New York, NY 10027, USA
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Abstract
Prions are lethal mammalian pathogens composed of aggregated conformational isomers of a host-encoded glycoprotein and which appear to lack nucleic acids. Their unique biology, allied with the public-health risks posed by prion zoonoses such as bovine spongiform encephalopathy, has focused much attention on the molecular basis of prion propagation and the "species barrier" that controls cross-species transmission. Both are intimately linked to understanding how multiple prion "strains" are encoded by a protein-only agent. The underlying mechanisms are clearly of much wider importance, and analogous protein-based inheritance mechanisms are recognized in yeast and fungi. Recent advances suggest that prions themselves are not directly neurotoxic, but rather their propagation involves production of toxic species, which may be uncoupled from infectivity.
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Affiliation(s)
- John Collinge
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, London WC1N 3BG, UK.
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Müller H, Stitz L, Wille H, Prusiner SB, Riesner D. Influence of water, fat, and glycerol on the mechanism of thermal prion inactivation. J Biol Chem 2007; 282:35855-67. [PMID: 17878157 DOI: 10.1074/jbc.m706883200] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Extending the recent analysis of the safety of industrial bovine fat-derived products for human consumption (Müller, H., Stitz, L., and Riesner, D. (2006) Eur. J. Lip. Sci. Technol. 108, 812-826), we investigated systematically the effects of fat, fatty acids, and glycerol on the heat destruction of prions. Prion destruction was qualitatively and quantitatively evaluated in PrP 27-30, or prion rods, by the inactivation of infectivity as well as by the degradation of the polypeptide backbone. Under all conditions analyzed, inactivation of prion infectivity was achieved more efficiently than backbone degradation by several orders of magnitude. The presence of fat enhanced prion inactivation and offers a mild treatment for prion decontamination. In contrast, the presence of fat, fatty acids, and especially glycerol protected the PrP 27-30 backbone against heat-induced degradation. Glycerol also protected against heat-induced inactivation of prion infectivity. A phase distribution analysis demonstrated that prions migrated to the interphase of a fat/water mixture at room temperature and accumulated in the water phase at higher temperatures. In a systematic study of the mechanism of prion destruction, we found an intermediate structure of PrP that has fewer fibrils in beta-sheet formation, lower resistance to protease digestion, greater aggregation, and reduced solubility compared with PrP 27-30 but retains residual infectivity. These findings suggest that prion infectivity depends on beta-sheet-rich fibrillar structure and that inactivation proceeds in a stepwise manner, which explains the tailing effect frequently observed during inactivation.
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Affiliation(s)
- Henrik Müller
- Institut für Physikalische Biologie, Heinrich Heine-Universität Düsseldorf, D-40225 Düsseldorf, Germany
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Fichet G, Comoy E, Dehen C, Challier L, Antloga K, Deslys JP, McDonnell G. Investigations of a prion infectivity assay to evaluate methods of decontamination. J Microbiol Methods 2007; 70:511-8. [PMID: 17640752 DOI: 10.1016/j.mimet.2007.06.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2007] [Accepted: 06/14/2007] [Indexed: 11/29/2022]
Abstract
Prions are unique infectious agents which have been shown to be transmitted iatrogenically through contaminated surfaces. Surface contamination is a concern on reusable medical devices and various industrial surfaces, but there is currently no standard, accepted model to evaluate surface prion decontamination. In this report, a set of both in vitro and in vivo methods were investigated based on the contamination of surface through artificial exposure to infected brain. An in vitro surface contamination protocol was developed with subsequent biochemical detection of the prion protein (PrPres). In parallel, the in vivo investigations included the contamination of different types of surface materials (stainless steel or plastic wires) with different prion strains (scrapie strain adapted to hamsters 263K or bovine spongiform encephalopathy strain adapted to mouse 6PB1). The in vivo models with various prion strains and brain homogenate dilutions reproducibly transmitted the disease and a relationship was established between the infectivity titre, the transmission rate and the incubation period. Moreover, the in vivo models were studied for their ability to demonstrate the efficacy of heat and chemical-based decontamination methods, with similar results. The in vivo scrapie method described is proposed as a standard to evaluate existing and developing prion decontamination technologies.
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Affiliation(s)
- Guillaume Fichet
- STERIS Laboratory, CEA/DSV/IMETI/SEPIA, Fontenay-aux-Roses, France.
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Unal A, Thyer J, Uren E, Middleton D, Braun M, Maher D. Investigation by bioassay of the efficacy of sodium hydroxide treatment on the inactivation of mouse-adapted scrapie. Biologicals 2007; 35:161-4. [PMID: 17074508 DOI: 10.1016/j.biologicals.2006.08.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2006] [Revised: 07/18/2006] [Accepted: 08/17/2006] [Indexed: 11/20/2022] Open
Abstract
Sodium hydroxide (NaOH) has been shown to reduce the infectivity of transmissible spongiform encephalopathy (TSE) agents. This study investigated the efficacy of sodium hydroxide at 0.1M, 0.25M and 0.5M concentrations for the inactivation of mouse-adapted scrapie strain ME7. Times and temperatures modelled conditions used in an industrial plasma fractionation plant for sanitisation of ultrafilters, and the sodium hydroxide component of Clean In Place sanitisation. The concentration of scrapie ME7 brain homogenate in NaOH test solutions was 1% (w/v). At the end of incubation periods, the samples were adjusted to neutral pH prior to intracerebral inoculation into mice for bioassay. The conditions of 0.1M NaOH at 60 degrees C for 2min and 0.25M NaOH at 30 degrees C for 60min were found to inactivate 3.96 and 3.93logs of scrapie, respectively. Use of 0.5M NaOH at 30 degrees C for 60 or 75min was found to inactivate >or=4.23 and 4.15logs of scrapie. This indicates that the use of these conditions in an industrial process would substantially reduce prion infectivity.
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Affiliation(s)
- A Unal
- CSL Bioplasma, 189-209 Camp Road, Broadmeadows, Victoria 3047, Australia
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Bade S, Frey A. Potential of active and passive immunizations for the prevention and therapy of transmissible spongiform encephalopathies. Expert Rev Vaccines 2007; 6:153-68. [PMID: 17408366 DOI: 10.1586/14760584.6.2.153] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Transmissible spongiform encephalopathies are fatal neurodegenerative disorders that affect humans and certain animals and are caused by prions. In most cases, infection occurs by ingestion of prions. Their long-time persistence in the environment creates a reservoir of potentially infectious matter that renders the eradication of the disease problematic. Unfortunately, no cure is available to date. Yet, for both the treatment of infected and the protection of uninfected individuals, active and passive immunizations have been shown to have a beneficial effect on the course of the disease. The current review provides an overview of such antibody-based approaches and assesses their feasibility and potential in prophylaxis and therapy of transmissible spongiform encephalopathies.
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Affiliation(s)
- Steffen Bade
- Research Center Borstel, Division of Mucosal Immunology, Borstel, Germany.
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