(2) Slow Virus and Prions Flashcards
Slow or chronic infections of the CNS
Slow Virus Infections
Incubation period for Slow Virus infection
YEAAAAAARSSSS
what are the 2 mentions slow virus infections
- Subacute Sclerosing Panencephalitis (SSPE)
- Progressive Multifocal Leukoencephalopathy (PML)
Slow Virus
- Rare disease caused by Measles virus
- occurs 2-10 years after recovery from measles
Subacute Sclerosing Panencephalitis (SSPE)
Slow Virus
what happens with the CNS in Subacute Sclerosing Panencephalitis (SSPE)
Slow progressive demyelination in the CNS = ending in death :(
Slow Virus
what are the initial symptoms of Subacute Sclerosing Panencephalitis (SSPE)
- memory loss
- irritability
- seizures
- involuntary muscle movements
- and/or behavioral changes
all symptoms leading to neurological deterioration and death
Slow Virus
what are found in the neurons and glial cells with SSPE infection
Large numbers of viral nucleocapsid
Slow Virus
Caused by JC virus (a polyomavirus)
Progressive Multifocal Leukoencephalopathy (PML)
Slow Virus
John Cunningham virus, a ds-DNA, icosahedral, and
naked
JC virus (a polyomavirus)
Slow virus
- Rare
- 85% of adults in the general population have the virus
Progressive Multifocal Leukoencephalopathy (PML)
Slow virus
PML virus usually remain dormant in what sites of the body
lymph nodes, bone
marrow, or kidneys throughout our lifetime
TOF
PML can cause CNS complication that occurs in immunocompromised
individuals (e.g., AIDS patients)
True
- Small, proteinaceous particles
- no nucleic acid
Prions
Cellular prion protein
PrPC
A modified prion
PrPSC
Prion
A normal protein in humans and other animals which is in extended form of recent infection with sars-cov-2
PrPC
Prion
Globular – resistant to proteases
PrPSC
Responsible for the disease causing of Prion
PrPSC
who suggested the model of how prions cause disease?
Stanley Prusiner
Prion - Pathogenesis
(1) PrPsc binds to the
normal PrPc on the cell surface and cause it to be processed into PrPsc
Prion - Pathogenesis
(2) The cell replenishes the ____, and the cycle continues.
PrPc
Prion - Pathogenesis
(3) ____ aggregates as amyloid-like plaques in the brain
PrPsc
Prion - Pathogenesis
what causes the aggregates as amyloid-like plaques in the brain
PrPsc
Prion - Pathogenesis
(4) e plaques consist of host protein might explain the lack of an immune response to these agents in ____
spongiform encephalopathies
SYmptoms of prion disease
- Loss of muscle control
- shivering
- tremors
- dementia
Prions - Symptoms
post mortem appearance
of the brain with large vacuoles in the cortex and cerebellum
Spongiform encephalopathies
TOF
Vaccine is available for treatment of Prions
F (No treatment available)
This the only way to minimize or prevent the prion disease
Control
Control for KURU
cessation of ritual of cannibalism
Control for GSS and CJD
disinfection of neurosurgical tools and electrodes in 5% hypochlorite, 1.0 M NaOH, or autoclaving at 15 psi for 1 hour
Prions - What DIsease
Host: Human
Mechanism: Cannibalism
Kuru
Prions - What DIsease
Host: Human
Mechanism: Spontaneous PrPc to PrPsc conversion or somatic mutation
Sporadic Creutzfeldt-Jacob Disease (CJD) and Sporadic fatal insomnia
Prions - What DIsease
Host: Human
Mechanism: nfection from prioncontaining material, e.g., dura mater, electrode
Iatrogenic CJD
Prions - What DIsease
Host: Human
Mechanism: Mutation in the PrP gene
Familial CJD and Gerstmann-Straussler
Scheincker (GSS) disease
Prions - What DIsease
Host: Human
Mechanism: Infection from BSE (bovine spongifrom encelopathy) (mad cow)
vCJD
Prions - What DIsease
Host: Human
Mechanism: D178N mutation in the
PrP gene, with M129
polymorphism
Familial Fatal Insomnia (FFI)
Prions - What DIsease
Host: Sheep
Mechanism: Infection in susceptible
sheep
Scrapie
Prions - What DIsease
Host: Cattle
Mechanism: Infection from
contaminated food
Bovine Spongiform Encephalopathy (BSE)
Prions - What DIsease
Host: Mink
Mechanism: Infection from sheep or cattle in food
Transmissible mink encephalopathy (TME)
