Prions

Question 1

How do people with Prions present?

Answer 1

Rapidly progressing dementia, loss of motor control, paralysis and wasting

Question 2

Name the infectious human prion diseases

Answer 2

Kuru, Iatrogenic CJD and Variant CJD

Question 3

How were people infected with Kuru?

Answer 3

Infection was due to cannibalistic handling and ingestion of brain tissue.

Question 4

Describe the risk of prion disease transmission

Answer 4

Blood to blood transmission only noted fro vCJD. Increased risk with lumbar puncture, handling CSF from patients

Question 5

How do we know prions are not viruses?

Answer 5

1. A prion specific nucleic acid genome has not been found
2. Prions are resistant to UV and ionizing radiation
3. Prions are sensitive to treatments that destroy proteins (Detergents)

Question 6

What is the major cause of prion replication?

Answer 6

The abnormal form of the protein causes a conformational change in the normal form of the protein.

Question 7

What is the model of infection of Prions?

Answer 7

1. Acquistion of abnormal protein.
2. Absorption from gut at Peyers Patches.
3. Phagocytosis by lymphoid cells and infection of lymphoid organs
4. Replication in lymphoid tissue
5. Entry into CNS via nerves that innervate lymphoid tissue.

Question 8

What are Gerstmann-Straussler disease symptoms?

Answer 8

Onset at 40 with a duration of 7 years. Cerebellar ataxia, memory loss, dementia

Question 9

Discuss Fatal Familial Insomnia

Answer 9

Autosomal Dominant; Due to aspartic acid mutation of PRNP gene. Presentss with insomnia, hallucinations and delirium.