Prions Flashcards
Symptoms of prion related disease?
Degeneration of the CNS, ataxia, dementia, and death
Histopathology in brain
Amyloid plaques
Vacuolated degeneration of tissue
Do you see inflammation and. Immune response with prions?
No - most likely because they are host-derived.
What are the 3 ways one can get prion related diseases?
Infection
Inheritance
Spontaneously
What are the diseases related to infection based prion disease?
Creutzfeldt Jakob Disease (CJD) - transmitted by transplantation of tissue from an infected individual
Kuru - transmitted by ritual consumption by family members of the deceased brains
Scarpie - mad cow disease / bovine spongiform encephalitis - transmitted via consumption of meat from infected animals.
How is it believed that prions get from the digestive tract to the brain?
Macrophages
What are some unusual features of the infectious agent?
High stability
Unusual composition
Little or no nucleic acid
No bacteria, virus, fungus, or protozoan which produces prion disease has ever been cultured from infected tissue
What protein is believed to cause prion related diseases?
PrP
What about the PrP is different that with normal people that causes the disease progression?
PrP transcription is the same, the AA sequence is the same, the only thing different is the conformation of PrP in infected and uninflected people.
- The infected conformation is more resistant and are not destroyed by cleavage.
Pruseiners hypothesis as to how PrP causes infection?
PrPc is in equilibrium with PrPc. Almost always, PrPc reverts back to PrPc, but sometimes it goes the other way and makes PrPsc. PrPsc then binds more PrPc and makes more PrPsc. This causes a cascade of a butt load of PrPsc to be made.
When you take PrPsc from a sheep and put it in a hamster, what species protein will be made in the hamster?
Hamster
