Preclinical Diagnosis of Scrapie by Immunohistochemistry of Third Eyelid Lymphoid Tissue

O’Rourke, Katherine I.; Baszler, Timothy V.; Besser, Thomas E.; Miller, Janice M.; Cutlip, Randall C.; Wells, G. A. H.; Ryder, S. J.; Parish, Steven M.; Hamir, Amir N.; Cockett, Noelle E.; Jenny, Allen L.; Knowles, Donald P.

doi:10.1128/jcm.38.9.3254-3259.2000

Cited by 246 publications

(158 citation statements)

References 29 publications

Supporting

Mentioning

153

Contrasting

Unclassified

Order By: Relevance

“…This clinical sign has been associated with an alteration in cranial nerves II and VII and the cerebellum, 27 a visual deficit by retinopathy, 49 and a wallerian degeneration of the optic nerve. 50 In conclusion, 3rd eyelid lymphoid tissue biopsies, which are useful for diagnosing preclinical scrapie in sheep, 16,17 are also a crucial tool in sequential clinical studies in naturally scrapie-affected sheep, as demonstrated in this study. Indeed, the diagnosis of affected animals in preclinical stages of the disease allowed the detection of precocious clinical signs, most remarkably hypoesthesia in the limbs.…”

Section: Discussionmentioning

confidence: 71%

“…21 One hundred forty-six sheep were selected on the basis of having genotypes that were susceptible to scrapie (R3 and R4 risk), 22 and these animals constituted an independent flock that was monitored for 18 months under veterinarian supervision and care acording to the National Research Council's guide for animal experimentation. Third eyelid lymphoid tissue biopsies from all 146 animals were taken to test for PrPsc in vivo 16 by immunohistochemical analysis with the L42 antibody a by previously described methods. 20 Results of testing showed that 18 sheep (12.5%) were positive for scrapie and that 128 (87.5%) were negative.…”

Section: Selection Of Animals Prp Genotyping and 3rd Eyelid Biopsiesmentioning

confidence: 99%

“…Routine diagnosis of scrapie is limited to clinical examinations and postmortem examinations. However, diagnosis during the preclinical stage is possible through the detection of PrPsc in the lymphoid tissues by a biopsy of the tonsil, nictitating membrane, or both, [14][15][16][17] constituting the current basis for live-animal testing. The study of lymphoid tissues is an important tool for pathologic studies of scrapie in preclinical and clinical stages of the disease, 18,19 but the study of the lymphoid tissues available in vivo can also be very useful for studying the clinical evolution of affected animals.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Detection and Clinical Evolution of Scrapie in Sheep by 3rd Eyelid Biopsy

Vargas

Luján

Bolea

et al. 2006

Veterinary Internal Medicne

View full text Add to dashboard Cite

The goal of this article was to characterize the clinical evolution of scrapie in naturally affected sheep. Eighteen sheep with scrapie diagnosed by examination of 3rd eyelid biopsy and 12 control ewes were studied throughout the duration of their disease. Diagnosis was confirmed postmortem by histopathologic, immunohistochemical, and Western blot analysis of nervous tissue. Complete clinical examinations were performed every 2 weeks for each animal, of which 3 clinical examinations per animal are reported. Those clinical signs that showed a significant frequency within the corresponding clinical examination were considered representative of each stage of the disease (ie, early, middle, and late). The representative clinical signs for the early stage were hypoesthesia in the limbs, alteration of mental status, and a body condition score ,3. Remarkably, hypoesthesia in the limbs was one of the 1st signs appearing during the early clinical stage in the affected animals, even before the appearance of other signs. For the middle stage, representative signs were the same as those for the early stage, together with hyporreflexia in the limbs, cardiac arrhythmia, pruritus/wool loss, and the appearance of the nibbling reflex. Representative clinical signs for the late stage were the same as those for the early and middle stage, together with head tremors, hyperexcitability to external stimuli, ataxia or gait abnormalities, and teeth grinding. On the basis of these results, we propose the calculation of an objective clinical index that allows the differentiation among clinical stages and that could be useful for further studies. The usefulness of 3rd eyelid lymphoid tissue biopsies for sequential clinical studies in naturally scrapie-affected sheep is demonstrated.

show abstract

Section: Discussionmentioning

confidence: 71%

Section: Selection Of Animals Prp Genotyping and 3rd Eyelid Biopsiesmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Detection and Clinical Evolution of Scrapie in Sheep by 3rd Eyelid Biopsy

Vargas

Luján

Bolea

et al. 2006

Veterinary Internal Medicne

View full text Add to dashboard Cite

show abstract

“…The one exception was the comparison of the proportion of deer that migrated by sex and CWD status because we were able to define migratory status of VHF-collared deer. We considered all available habitat to present an equal risk of CWD-infection because the area has been endemic for CWD for 50 years (O'Rourke et al 2000), which may allow CWD contamination to become homogenous across an area, particularly riparian habitats. Chronic wasting disease was first detected in deer hunt area 65 in 1999 through both targeted (i.e., suspected clinical CWD cases) and hunter-killed surveillance (W. H. Edwards, personal communication), although surveillance prior to 1999 was minimal.…”

Section: Statistical Analysesmentioning

confidence: 99%

Chronic wasting disease influences activity and behavior in white‐tailed deer

et al. 2017

View full text Add to dashboard Cite

Chronic wasting disease (CWD) is an infectious and fatal transmissible spongiform encephalopathy of members of the family Cervidae. Although CWD has been a serious concern among wildlife managers in several states in the United States and 2 Canadian provinces for over a decade, it is not known how CWD affects movement of hosts during the preclinical and clinical phases of disease. We hypothesized that normal movement patterns are altered by CWD. We evaluated migratory status, migration corridors, dispersal behavior, hourly activity patterns, home range areas, and resource selection for white-tailed deer (Odocoileus virginianus) of known CWD status as a means of understanding how CWD infection influenced habitat use and disease spread. We captured deer, tested for CWD by tonsil biopsy, marked deer with radio-transmitters (2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010) or global positioning system collars (2006)(2007)(2008)(2009)(2010), and recaptured individuals annually for CWD testing. The proportion of CWD-positive females that migrated was significantly less than CWD-positive males. All deer that were CWD-negative were more active than their CWD-positive cohabitants, which was most pronounced in fall for males when CWD-positive deer were significantly less active throughout the day. Home range areas were small (x ¼ 1.99 km 2 ) and were larger for CWD-negative females than CWD-positive females. Resource selection analyses indicated that all deer, regardless of CWD status, sex, or migratory status selected riparian habitats. Riparian habitats represent high CWD risk areas that should be targeted for potential disease management actions (e.g., surveillance, culling, environmental treatments). Ó

show abstract

“…Thus, it was appropriate to replace Sip terminology with Prnp polymorphisms or PrP genotypes. The ovine Prnp-coding region has been shown to be highly polymorphic, and to date at least 15 apparently mutually exclusive alleles (mono-mutated) have been described, most of which are rare and as yet unrelated to disease development (19,(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39) (Fig. 2).…”

Section: Polymorphisms In the Coding Region Of Prnp -The Story Of ''Smentioning

confidence: 99%

Influence of the prion protein gene, Prnp, on scrapie susceptibility in sheep

Tranulis

2002

APMIS

View full text Add to dashboard Cite

Tranulis MA. Influence of the prion protein gene, Prnp, on scrapie susceptibility in sheep. APMIS 2002;110:33-43. Natural scrapie in sheep occurs through a complex interplay between host genetic elements and various strains of the infectious scrapie agent. Scrapie-related polymorphisms in the coding region of the prion protein (PrP) gene, Prnp, have been studied in a number of breeds. The disease-promoting V 136 allele, and the susceptibility-reducing R 171 allele, have proved to be most important. However, variation in the coding region of Prnp cannot alone explain the diverse patterns of scrapie susceptibility in various breeds. For instance, in many breeds plagued with scrapie, the V 136 allele appears to be a rarity. The R 171 allele greatly reduces scrapie susceptibility. This lays the molecular foundation for marker-assisted breeding for reduced scrapie susceptibility now underway in many countries. Although potentially important, and still under investigation, variable expression level and pattern of the ovine Prnp appears to be of little importance for the occurrence of natural scrapie. Studies of scrapie in mice also indicate that genetic elements other than Prnp may have a strong influence on scrapie incubation time, and hence susceptibility. Narrowing down the search to focus on these elements and identification of candidate genes are important tasks for future research in sheep scrapie.

show abstract

Preclinical Diagnosis of Scrapie by Immunohistochemistry of Third Eyelid Lymphoid Tissue

Cited by 246 publications

References 29 publications

Detection and Clinical Evolution of Scrapie in Sheep by 3rd Eyelid Biopsy

Detection and Clinical Evolution of Scrapie in Sheep by 3rd Eyelid Biopsy

Chronic wasting disease influences activity and behavior in white‐tailed deer

Influence of the prion protein gene, Prnp, on scrapie susceptibility in sheep

Contact Info

Product

Resources

About