The low-density lipoprotein receptor plays a role in the infection of primary human hepatocytes by hepatitis C virus.
OBJECTIVE
The direct implication of low-density lipoprotein receptor (LDLR) in hepatitis C virus (HCV) infection of human hepatocyte has not been demonstrated. Normal primary human hepatocytes infected by serum HCV were used to document this point.


METHODS
Expression and activity of LDLR were assessed by RT-PCR and LDL entry, in the absence or presence of squalestatin or 25-hydroxycholesterol that up- or down-regulates LDLR expression, respectively. Infection was performed in the absence or presence of LDL, HDL, recombinant soluble LDLR peptides encompassing full-length (r-shLDLR4-292) or truncated (r-shLDLR4-166) LDL-binding domain, monoclonal antibodies against r-shLDLR4-292, squalestatin or 25-hydroxycholesterol. Intracellular amounts of replicative and genomic HCV RNA strands used as end point of infection were assessed by RT-PCR.


RESULTS
r-shLDLR4-292, antibodies against r-shLDLR4-292 and LDL inhibited viral RNA accumulation, irrespective of genotype, viral load or liver donor. Inhibition was greatest when r-shLDLR4-292 was present at the time of inoculation and gradually decreased as the delay between inoculation and r-shLDLR4-292 treatment increased. In hepatocytes pre-treated with squalestatin or 25-hydroxycholesterol before infection, viral RNA accumulation increased or decreased in parallel with LDLR mRNA expression and LDL entry.


CONCLUSIONS
LDLR is involved at an early stage in infection of normal human hepatocytes by serum-derived HCV virions.
Molina
Sonia
S
Inserm, U632, Hepatic Physiopathology, 1919 route de Mende, 34293 Montpellier Cedex 5, France.
Castet
Valérie
V
Fournier-Wirth
Chantal
C
Pichard-Garcia
Lydiane
L
Avner
Rachel
R
Harats
Dror
D
Roitelman
Joseph
J
Barbaras
Ronald
R
Graber
Pierre
P
Ghersa
Paola
P
Smolarsky
Moshe
M
Funaro
Ada
A
Malavasi
Fabio
F
Larrey
Dominique
D
Coste
Joliette
J
Fabre
Jean-Michel
JM
Sa-Cunha
Antonio
A
Maurel
Patrick
P
D000293:Adolescent; D000328:Adult; D000368:Aged; D000906:Antibodies / Q000502:physiology; D000924:Anticholesteremic Agents / Q000494:pharmacology; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D018821:CD18 Antigens / Q000502:physiology; D002478:Cells, Cultured; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D016174:Hepacivirus / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology; D006526:Hepatitis C / Q000473:pathology / Q000503:physiopathology*; D022781:Hepatocytes / Q000473:pathology / Q000821:virology*; D006801:Humans; D006888:Hydroxycholesterols / Q000494:pharmacology; D008075:Lipoproteins, HDL / Q000502:physiology; D008077:Lipoproteins, LDL / Q000502:physiology; D008297:Male; D008875:Middle Aged; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism; D011973:Receptors, LDL / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D051122:Scavenger Receptors, Class B / Q000502:physiology; D014233:Tricarboxylic Acids / Q000494:pharmacology; D019562:Viral Load; D014771:Virion
D000906:Antibodies; D000924:Anticholesteremic Agents; D019086:Bridged Bicyclo Compounds, Heterocyclic; D018821:CD18 Antigens; D006888:Hydroxycholesterols; D008075:Lipoproteins, HDL; D008077:Lipoproteins, LDL; D012367:RNA, Viral; D011973:Receptors, LDL; C495124:SCARB1 protein, human; D051122:Scavenger Receptors, Class B; D014233:Tricarboxylic Acids; C075117:squalestatin 1; C007997:25-hydroxycholesterol