Furthermore, the lipid composition of HCV virions
Biology 2014, 3 895
indicates that more than half of the total HCV lipids are composed of cholesteryl esters, which resembles
the lipid content of VLDL and low-density lipoproteins (LDL) [24]. Due to their association with
lipoproteins, HCV particles were named lipoviroparticles (LVP) [7]. Interestingly, LVP are enriched in
apoE as compared to VLDL. Indeed, purified HCVcc particles bear approximately 300 molecules of
apoE [24], whereas VLDL contains only five to seven apoE molecules [25]. However, the average
density of HCV particles isolated in vivo is lower compared to HCVcc produced in vitro [18]. This is
likely due to some defect in VLDL biogenesis in Huh-7 [26], the hepatoma cell line generally used to
produce HCV in cell culture. These cells are indeed deficient in producing mature VLDL due to poor
efficiency of apoB100 lipidation.