Related Experiment Video
Updated: Jul 13, 2026
13:42
Clinical Examination Protocol to Detect Atypical and Classical Scrapie in Sheep
Published on: January 19, 2014
Classical sheep transmissible spongiform encephalopathies: pathogenesis, pathological phenotypes and clinical disease
1Veterinary Laboratory Agency, Lasswade Laboratory, Pentlands Science Park, Bush Loan, Penicuik, Midlothian, Scotland, UK. m.jeffrey@vla.defra.gsi.gov.uk
Neuropathology and Applied Neurobiology
|July 10, 2007
Summary
Scrapie, a prion disease in sheep, involves abnormal prion protein (PrPd) accumulation. Distinct PrPd profiles reveal strain-specific information and cellular tropisms, offering insights into transmission and food safety.
Area of Science:
- Veterinary Neurology
- Prion Disease Research
- Immunohistochemistry
Background:
- Scrapie is a transmissible spongiform encephalopathy (TSE) affecting sheep, goats, and moufflon.
- Pathology involves vacuolation, gliosis, and abnormal prion protein (PrPd) accumulation in the brain.
- Unlike human counterparts, sheep scrapie shows no significant neuronal loss, complicating the understanding of clinical signs.
Purpose of the Study:
- To characterize different strains of sheep TSEs using immunohistochemical methods.
- To investigate the cellular tropisms and PrPd processing in various infected cell types.
- To explore the relationship between PrPd accumulation in different tissues and disease transmission.
Main Methods:
- Immunohistochemistry was used for PrPd epitope mapping and profiling.
- Characterization of PrPd truncation sites and accumulation patterns.
- Comparison of immunochemical methods with PrPd mapping results.
Main Results:
- Differences in PrPd truncation sites were observed between sheep TSE strains and infected cell types.
- Distinct PrPd profiles provided strain- and source-specific information on cellular tropisms and PrPd processing.
- PrPd accumulation was noted in lymphoid tissues, peripheral nervous system, and other non-neural tissues.
Conclusions:
- PrPd profiling offers detailed insights into sheep TSE strains and cellular tropisms, surpassing immunoblotting capabilities.
- The role of PrPd accumulation in neurological dysfunction in sheep scrapie remains unclear due to lack of neuronal loss.
- PrPd presence in non-nervous tissues suggests potential transmission routes and food safety implications.
Related Concept Videos
03:03Amyloid Fibrils
Amyloid fibrils are aggregates of misfolded proteins. Under most circumstances, misfolded proteins are either refolded by chaperone proteins or degraded by the proteasome. However, in the case of a mutation or a disease, these proteins can accumulate to form large clusters and often further assemble to form elongated fibers, called fibrils.
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
03:03Amyloid Fibrils
Amyloid fibrils are aggregates of misfolded proteins. Under most circumstances, misfolded proteins are either refolded by chaperone proteins or degraded by the proteasome. However, in the case of a mutation or a disease, these proteins can accumulate to form large clusters and often further assemble to form elongated fibers, called fibrils.
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
01:29Subviral Agents
Subviral agents are infectious entities that resemble viruses but lack one or more viral components, such as a capsid or essential replication machinery. These agents include viroids, prions, and satellites, each possessing distinct structural and functional characteristics that influence their mode of infection and replication.Viroids are the simplest subviral agents, consisting of circular, single-stranded RNA molecules without a protein coat. They exclusively infect plants, relying entirely...
01:26Encephalitis ll: Pathophysiology
Encephalitis is inflammation of the brain parenchyma caused by direct viral invasion or immune-mediated mechanisms triggered by infections or tumors. Both processes lead to neuronal injury, disrupted neurotransmission, and diverse neurological symptoms, often with overlapping clinical and pathological features.Autoimmune EncephalitisIn autoimmune encephalitis, antibodies target neuronal antigens on cell surfaces, synapses, or within neurons. A key example is anti-NMDAR encephalitis, which can...
01:28Toxoplasmosis
Toxoplasmosis, a zoonotic disease caused by the protozoan Toxoplasma gondii, poses significant public health challenges globally due to its high seroprevalence and varied clinical manifestations. As an obligate intracellular parasite, T. gondii can infect all warm-blooded vertebrates, but felids are its only definitive hosts, shedding unsporulated oocysts into the environment. Humans typically acquire the infection through ingestion of tissue cysts in undercooked meat or oocysts from...
01:28Rabies
Rabies is a lethal zoonotic disease caused by a single-stranded, negative-sense RNA virus of the Lyssavirus genus, within the family Rhabdoviridae. Its primary mode of transmission to humans is through bites or saliva-contaminated scratches from infected mammals such as dogs, bats, raccoons, or foxes. Transmission can also occur if infectious saliva contacts abraded skin or intact mucous membranes, including the conjunctiva.Viral Entry and Early ReplicationOnce introduced at the bite or scratch...