HCV
Terms
undefined, object
copy deck
- Describe the genome of HCV.
- (+) ssRNA with an IRES in the 5' NTR.
- How is HCV translated?
- The viral genome has one ORF which is translated as a single polyprotein that is subsequently cleaved by cellular and viral proteases.
- What enzymes does the HCV genome code for?
-
*proteases for polyprotein cleavage
*RNA-dependent RNA polymerase - How many forms of HCV exist?
- There are 6 genotypes and ~100 subtypes.
- Following acute infection, what clincal presentation does HCV show?
- Most (70-100%) patients convert to chronic carriers who then show sequential episodes of acute inflammation. 40% of these carriers will develop cirrhosis and HCC.
- What is the key immune player in clearance of HCV?
- Interferon
- Why is immunity against HCV typically less than effective? What can be inferred from a positive anti-HCV blood test?
- The virus shows antigenic drift within a single patient ("quasi species") and thus is able to evade immune attacks. The presence of anti-HCV signals ongoing infection and viremia - not recovery.
- How is HCV transmitted?
-
*blood
*body fluids
*needles
*vertically - How is HCV diagnosed?
- ELISA for HCV antibodies.
- What problems have been encountered in the development of a vaccine for HCV?
- There are multiple serotypes and even within a single patient there is antigenic drift.
- What treatment is available for HCV? What kind of success is seen?
- Interferon alone or in combination with ribavirin is used. There have been mixed results including supression of viremia with rebound of the virus following discontinuation of therapy.