Prions

Question 0

Creutzfeldt-Jacob disease (CJD)

Answer 0

Sporadic: no known cause
Familial: inherited
Iatrogenic: exposure during medical procedures

Question 1

Causes of prion disease

Answer 1

Misfolding converts PrPc (usually maintains brain white matter) into PrPsc (scrapie form, can be experimentally transmitted between animals WITH PrPc)
PrPsc nucleus then recruits other PrPc to convert to PrPsc
Causes neurodegeneration
Infectious but no genetic material

Question 2

sCJD

Answer 2

Spongiform encephalopathy (brain disorder)
Loss of brain function is rapid unlike Alzheimer's 
Myoclonus (sudden jerk)

Question 3

sCJD diagnosis, prognosis, epidemiology

Answer 3

Brain biopsy (accumulation of PrPsc, neural loss without inflammation, spongiform change), cerebrospinal fluid, MRI, electroencephalography

No treatment, die within year

Higher among older population 65 yrs

Question 4

Variant CJD

Answer 4

Type 4 prion
Bovine to human transmission via CNS, retina, etc but not muscle or milk
Similar to vCJD but slower ~14 months
Affects lymphoreticular tissues (tonsils)
Onset ~29yrs

Question 5

What country did prions originate from?

Answer 5

Great Britain

Question 6

Resistant to physical decontamination methods except

Answer 6

Autoclave

Question 7

Alzheimer’s disease

Answer 7

Progressive dementia
After 60 yrs
PrPc binds to amyloid-B peptides, and if misfolded will cause PrPc to misfolded too