The role of scavenger receptor BI in hepatitis - eTheses Repository ...

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In 1992 Thomssen et. al. demonstrated that low density HCV particles could
be precipitated with anti-ApoB-100 antibodies, indicating an association with
low density lipoproteins (312, 313). However understanding the nature of this
association would go little further until 2002 when Andre et. al. used electron
microscopy to study the sera of HCV infected patients (8). They observed low
density spherical structures of ~100nm, atypical of normal human lipoproteins,
treatment with detergent revealed central viral capsids that could be
recognised using HCV core antibodies, they named these structures HCV
lipo-viro-particles (LVPs) (8).
Subsequent studies using infected patient liver and serum samples revealed
that LVPs contain HCV RNA and structural proteins, ApoB-100/48, ApoE,
ApoC, triglyceride, cholesterol and phospholipids (8, 77, 210, 232, 233, 312).
However, analysis of their lipid composition suggests that they are not merely
HCV particles carrying surface lipoproteins (8). LVPs have characteristics of
both lipoproteins and virus particles and are believed to circulate as functional
carriers of dietary lipids (77). Indeed, HCV LVP are reported to interact with
the metabolic enzyme lipoprotein lipase, however this is believed to facilitate
particle entry along a non-permissive pathway (9).
Prior to an in vitro system to measure particle infectivity, observations were
made using patient sera and Chimpanzees. These early studies suggested
that low density LVP are more infectious than those of a higher density (45,
128). Initial experiments to elucidate the mechanism of LVP formation
measured the association of HCV structural proteins with lipoproteins,