Hep C intro and epid. Flashcards
Define hepatitits
Inflammation of liver
Is HCV enveloped?
Yes
What is the transmission method of HCV?
Parenteral
Does HCV cause acute or chronic hepatitis?
Chronic
Why isn’t HCV transmission enteric?
Gut bile would break down envelope
What enzyme is released during liver damager?
Alanine aminotransferase (ALT)
What diseases can HCV develop into?
Chornic liver diseases, like firbosis and cirrhosis
Hepatocellular carcinoma
What is cirrhosis
Cirrhosis is a chronic liver disease that occurs when scar tissue replaces healthy liver tissue
Is there a HCV vaccine?
No
Is the nucleotide sequence of HCV variable?
Vary.
How many genotypes of HCV
8 genotypes
What HCV genotypes are commenest in W. Europe?
1-3
Most common genotype of HCV in Egypt? And why?
Genotype 4
Due to schistomsomiasis campaign
How is HCV diagnosed?
HCV Ab, can take many months to be +ve
qRT-PCR –> determine genotype
What was HCV first termed?
Non-A, non-B hepatitis. NANBH
What chemical agent proved that HCV was small and eveloped?
Filterable and inactivated by chloroform
How is HCV genome cloned?
High titre human serum is centrifuged
Extract RNA
RT to form cDNA
Clone into lambda phage
Infect E,coli with lambda phage library
Take imprint of plate using nitrocellulose membrane
Prove membrane w/ antiserum from NANBH patients
Return to original plate and pick plaques and sequence
How many seperate proteins is the HCV genome cleaved into?
10 seperate proteins
What family is HCV part of?
Flaviviridae
IS HCV genome linear or circular?
Linear
What nucleic acid is the HCV genome?
Positive sense single stranded RNA
What are the structural HCV genes?
Core,
E1 and E2 - envelope glycoproteins
(p7)
What are the non-structural HCV genes?
NS2
NS3 + NS4A –> protease/helicase
NS4B
NS5A
NS5B - RdRp
What 5’ and 3’ structures does the orthoflavivirus genus have?
m7G cap and poly(A) tail
Example of orthoflaviviruses
Dengue
West Nile
Yellow Fever
Zika
What genus is HCV a part of?
Hepacivirus
What animal and what organ system was Equine hepacivirus girst isolated from?
Dog, respiratory system
In what structure is HCV studied?
Sub-genomic replicons and cell culture infectious systems
What genes are SGRs missing to study HCV
Core, E1, E2, p7
Issue with infectious clones of HCV?
RNA derived from infectious clones didn’t replicate in cultured cells
What genes replace the removed genes in pHCV SGRs
NPT and EMCV IRES
What cell are transfected with pSGR-HCV ?
Huh7
What are Huh7 cells?
Human hepatoma cell line
Issues with SGR-HCV
Only work in Huh7 cells
Subsequent replicons with full length genome don’t produce virus
Only study part of lifecycle
