WEEK 3: HEPATITIS C VIRUS Flashcards
HVC belongs to Flaviviridae family tree - what’s that?
a family of positive polarity, single-stranded, enveloped RNA viruses
how many pathogens is in the flaviviridae family
69 pathogens - this family is a major global health problem
is there an effective vaccine against HVC?
no.
why is egypt at the forefront for HCV treatment?
(around 50 years ago) A huge problem occured when schistosomiasis affected many people (a parasite in the Nile that spread to humans via freshwater snails). Mass treatment with repeatedly used contaminated needles rapidly spread HCV.
In Egypt, how many jabs were used to treat people with anti-schistosomial therapy?
360,000,000 over 19 years
how big is the HCV virus?
50-80nm
how does HCV hide itself from neutralising antibodies?
the virus moves onto low-density lipoproteins and makes the lipid bigger
what is formed when the HCV virus moves onto the lipoprotein in the body?
it forms a lipoviral particle
what cells are infected by HCV?
70% of infections surround liver cells. Hepatocytes, intestinal enterocytes, B lymphocytes, astrocytes (causes neurological damage)
how is HCV transmitted?
within host - cell to cell. host to host - contaminated blood transfusion, needle stick injury or drug use
how many individuals resolve HCV virus?
20%
how many victims of HCV develop cirrhosis?
25% - this is within 20 years
what are the symptoms of HCV?
high levels of bilirubin makes the skin yellow, jaundice, ascites (fluid in abdomen), varices (enlarged veins), pruritis (severe itching), lichen planus (rash)
What does a positive polarity RNA virus mean?
it gets picked up by a host ribosome and is translated
What is the HCV genome flanked by?
on either side by its 5’ untranslated region and a 3’ untranslated region
how is HCV genome read?
one continuous open reading frame
how many genes are in the genome?
10 genes
what are the phosphoprotein inhibitors?
elbasvir, ledipasvir, velpatasvir, pibrentasvir
what 3 protein have been used and targeted by the pharmaceutical company successfully?
serine protease, phosphoprotein and RNA dependent RNA polymerase
What antibodies are initially looked for?
they look for antibodies that would bind to hep A or hep B. A negative test means they don’t have theses diseases. A pcr test for hep C antibodies is then tested.
What is detected after confirmation of HCV?
quantity of the virus using a quantitative PCR
if a “naked” HCV virus enters a cell, what cell receptor does it bind to?
Glycosaminoglycans (GAGs)
if a “lipidated” HCV virus enters a cell, what cell receptor does it bind to?
low density glycoprotein receptor
endosomes store virons then theya cidiify
librates rna
rna is picked up by host cell ribosomes
akes viral prtoines
in er^^
then some of the rna initally in infected cell must be replicated. positive polarity rna virus must be regulated by a negative intermediate.
NS4b gene producesprotein that produces viral asselbmy web factories. here vireses are made in infected cells.
then exocytosed out o f cell
transort it medaited out of cell where they acquire glycoprotein envelope.
