302 Pathogenesis of viral hepatitis

Question 1

What are the different action of INF α/β?

Answer 1

-Down regulates viral protein synthesis
-Inhibit viral replication
-Promote adaptive immunity via MHC class 1
expression on APC
-Activates NK, CD8 and dendritic cells
-Activate cell death through secretions of perforins

Question 2

What causes a persistent Hep B infection?

Answer 2

Young age because the immune system is immature and can’t clear the virus

Or Immunosuppression because there is an inadequate immune response

Question 3

Can the body naturally clear a Hep B infection?

Answer 3

Yes

It’s an acute infection that the body fights before it can get chronic

Question 4

What is IL-10?

Answer 4

An anti inflammatory cytokine

The Hep B virus can induce it’s effects so it can evade the immune response

Question 5

What other Hep virus needs to be present so that a Hep D virus can cause disease?

Answer 5

Hep B

Question 6

How is Hep B transmitted?

Answer 6

When blood, semen, or other body fluids

Question 7

What is the treatment for chronic Hep B virus?

Answer 7

Tenofovir/Tenofovir alafenamide
Entecavir
Pegylated interferon

They don’t cure the disease. They minimise it’s action and may encourage the immune response to fight the virus

Question 8

What is Hep C virus?

Answer 8

RNA virus
Rapid rate of replication
80% develop chronic infection
No vaccine

Transmitted by blood

Question 9

Why does Hep C become chronic?

Answer 9

High replicative rate and viral antigen load
- CD8+/CD4+ T cell anergic/exhausted: unable to proliferate/secrete cytokines
- Display normal immune responses to other viruses

High error rate of RNA dependent RNA polymerase leading to mutations
- Escape neutralising antibodies and
cellular immune responses

It interferes with the immune response