Prion in Saliva of Bovine Spongiform Encephalopathy–Infected Cattle

Okada, Hiroyuki; Murayama, Yuichi; Shimozaki, Noriko; Yoshioka, Miyako; Masujin, Kentaro; Imamura, Morikazu; Iwamaru, Yoshifumi; Matsuura, Yuichi; Miyazawa, Kohtaro; Fukuda, Shigeo; Yokoyama, Takashi; Mohri, Satoshi

doi:10.3201/eid1812.120528

Cited by 8 publications

(4 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Influenced by the observations of Haley et al and , we modified our previous PMCA method by increasing both sonication time and temperature, and consequently total energy delivered, and observed prion amplification in saliva samples that inhibited in RT-QuIC. Previous publications reporting detection of BSE prions in saliva described additional steps, including the addition of sulfated dextrans and sodium phosphotungstic acid precipitation (24,25), whereas we did not find those steps necessary. We also found that evaluation of PMCA products by RT-QuIC versus Western blotting increased sensitivity and enabled fewer PMCA amplification rounds and therefore less brain homogenate substrate.…”

Section: Discussioncontrasting

confidence: 79%

“…We used CWD ϩ saliva, which normally is inhibited in RT-QuIC, to seed transgenic mouse brain homogenate substrate in PMCA. In studies which detected BSE prions in saliva with PMCA, Murayama et al suggested that a higher temperature and the subsequent increased energy output improved sensitivity (24,25). We performed our PMCA reaction at 50°C with an average energy of 1,000,000 J in the first round over 3 days and 300,000 J in all subsequent 24-h rounds.…”

Section: Resultsmentioning

confidence: 99%

“…In contrast, PMCA was unable to detect CWD prions in urine and saliva samples that induced infection in transgenic mouse bioassays (23). However, an optimized version of PMCA could detect prions in saliva from cows experimentally infected with bovine spongiform encephalopathy (BSE) (24,25). To improve the detection of prions in saliva, which is necessary to understand CWD transmission, we endeavored to both identify the assay inhibitor(s) in saliva and develop a sensitive method to detect CWD prions despite the presence of such inhibitors.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Modified Protein Misfolding Cyclic Amplification Overcomes Real-Time Quaking-Induced Conversion Assay Inhibitors in Deer Saliva To Detect Chronic Wasting Disease Prions

et al. 2018

View full text Add to dashboard Cite

Chronic wasting disease (CWD), a fatal neurodegenerative prion disease of cervids, has spread across North America and has been detected in The Republic of Korea, Finland, and Norway. CWD appears to spread by horizontal transmission, and prions shed in saliva, feces, and urine are thought to contribute. However, studies investigating the rapid spread of CWD have been hampered by assay inhibitors and a lack of consistent and sensitive means to detect the relatively low levels of prions in these samples. Here we show that saliva frequently contains an inhibitor of the real-time quaking-induced conversion assay (RT-QuIC) and that the inhibitor is a member of the mucin family. To circumvent the inhibitor, we developed a modified protein misfolding cyclic amplification (PMCA) method to amplify CWD prions in saliva that were undetectable or ambiguous by RT-QuIC. Our results reinforce the impact of saliva in horizontal CWD transmission and highlight the importance of detection optimization.

show abstract

Section: Discussioncontrasting

confidence: 79%

Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Modified Protein Misfolding Cyclic Amplification Overcomes Real-Time Quaking-Induced Conversion Assay Inhibitors in Deer Saliva To Detect Chronic Wasting Disease Prions

et al. 2018

View full text Add to dashboard Cite

show abstract

“…The same method was applied to the detection of PrP Sc in saliva of cattle at terminal stage, early clinical stage and two months before onset of clinical signs. The authors estimated salivary PrP Sc amount to be equivalent to that in 10 −12 dilution of brain homogenate, however failed to detect in cattle three to five months prior to the onset of the disease [302]. Another modified PMCA protocol using L-Arginine ethylester also allowed early detection of prions in saliva as well as in urine of atypical BSE-infected macaques.…”

Section: Salivamentioning

confidence: 99%

Detection of Pathognomonic Biomarker PrPSc and the Contribution of Cell Free-Amplification Techniques to the Diagnosis of Prion Diseases

et al. 2020

View full text Add to dashboard Cite

Transmissible spongiform encephalopathies or prion diseases are rapidly progressive neurodegenerative diseases, the clinical manifestation of which can resemble other promptly evolving neurological maladies. Therefore, the unequivocal ante-mortem diagnosis is highly challenging and was only possible by histopathological and immunohistochemical analysis of the brain at necropsy. Although surrogate biomarkers of neurological damage have become invaluable to complement clinical data and provide more accurate diagnostics at early stages, other neurodegenerative diseases show similar alterations hindering the differential diagnosis. To solve that, the detection of the pathognomonic biomarker of disease, PrP Sc , the aberrantly folded isoform of the prion protein, could be used. However, the amounts in easily accessible tissues or body fluids at pre-clinical or early clinical stages are extremely low for the standard detection methods. The solution comes from the recent development of in vitro prion propagation techniques, such as Protein Misfolding Cyclic Amplification (PMCA) and Real Time-Quaking Induced Conversion (RT-QuIC), which have been already applied to detect minute amounts of PrP Sc in different matrixes and make early diagnosis of prion diseases feasible in a near future. Herein, the most relevant tissues and body fluids in which PrP Sc has been detected in animals and humans are being reviewed, especially those in which cell-free prion propagation systems have been used with diagnostic purposes.

show abstract

Prion Diseases: Infection Protection

Andersen

2019

Prevention and Control of Infections in Hospitals

View full text Add to dashboard Cite

Prion in Saliva of Bovine Spongiform Encephalopathy–Infected Cattle

Cited by 8 publications

References 8 publications

Modified Protein Misfolding Cyclic Amplification Overcomes Real-Time Quaking-Induced Conversion Assay Inhibitors in Deer Saliva To Detect Chronic Wasting Disease Prions

Modified Protein Misfolding Cyclic Amplification Overcomes Real-Time Quaking-Induced Conversion Assay Inhibitors in Deer Saliva To Detect Chronic Wasting Disease Prions

Detection of Pathognomonic Biomarker PrPSc and the Contribution of Cell Free-Amplification Techniques to the Diagnosis of Prion Diseases

Prion Diseases: Infection Protection

Contact Info

Product

Resources

About