title: Expression and functionality of Toll- and RIG-like receptors in HepaRG cells.
abstract: OBJECTIVE
  HepaRG cells are considered as the best surrogate model to primary human hepatocyte (PHH) culture to investigate host-pathogen interactions. Yet their innate immune functions remain unknown. In this study, we explored the expression and functionality of Toll-like (TLR) and retinoic acid-inducible gene-1 (RIG-I)-like receptors (RLR) in these cells.
  
  
  METHODS
  Gene and protein expression levels of TLR-1 to 9 and RLR in HepaRG were mainly compared to PHH, by RT-qPCR, FACS, and Western blotting. Their functionality was assessed, by measuring the induction of toll/rig-like themselves and several target innate gene expressions, as well as the secretion of IL-6, IP-10, and type I interferon (IFN), upon agonist stimulation. Their functionality was also shown by measuring the antiviral activity of some TLR/RLR agonists against hepatitis B virus (HBV) infection.
  
  
  RESULTS
  The basal gene and protein expression profile of TLR/RLR in HepaRG cells was similar to PHH. Most receptors, except for TLR-7 and 9, were expressed as proteins and functionally active as shown by the induction of some innate genes, as well as by the secretion of IL-6 and IP-10, upon agonist stimulation. The highest levels of IL-6 and IP-10 secretion were obtained by TLR-2 and TLR-3 agonist stimulation respectively. The highest preventive anti-HBV activity was obtained following TLR-2, TLR-4 or RIG-I/MDA-5 stimulations, which correlated with their high capacity to produce both cytokines.
  
  
  CONCLUSIONS
  Our results indicate that HepaRG cells express a similar pattern of functional TLR/RLR as compared to PHH, thus qualifying HepaRG cells as a surrogate model to study pathogen interactions within a hepatocyte innate system.
authors.affiliation: INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France; Pharma Research & Early Development (pRED), Roche Innovation Center Basel, F. Hoffmann-La Roche AG, 4070 Basel, Switzerland.
authors.forename: Souphalone
authors.initials: S
authors.lastname: Luangsay
authors.affiliation: INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France; Pharma Research & Early Development (pRED), Roche Innovation Center Basel, F. Hoffmann-La Roche AG, 4070 Basel, Switzerland.
authors.forename: Malika
authors.initials: M
authors.lastname: Ait-Goughoulte
authors.affiliation: INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France.
authors.forename: Maud
authors.initials: M
authors.lastname: Michelet
authors.affiliation: INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France.
authors.forename: Océane
authors.initials: O
authors.lastname: Floriot
authors.affiliation: INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Bonnin
authors.affiliation: INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France.
authors.forename: Marion
authors.initials: M
authors.lastname: Gruffaz
authors.affiliation: Centre Léon Bérard (CLB), 69008 Lyon, France; INSERM U1032, 69003 Lyon, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Rivoire
authors.affiliation: Pharma Research & Early Development (pRED), Roche Innovation Center Basel, F. Hoffmann-La Roche AG, 4070 Basel, Switzerland.
authors.forename: Simon
authors.initials: S
authors.lastname: Fletcher
authors.affiliation: Pharma Research & Early Development (pRED), Roche Innovation Center Basel, F. Hoffmann-La Roche AG, 4070 Basel, Switzerland.
authors.forename: Hassan
authors.initials: H
authors.lastname: Javanbakht
authors.affiliation: INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France.
authors.forename: Julie
authors.initials: J
authors.lastname: Lucifora
authors.affiliation: INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France; Hospices Civils de Lyon (HCL), 69002 Lyon, France; Institut Universitaire de France (IUF), 75005 Paris, France. Electronic address: fabien.zoulim@inserm.fr.
authors.forename: Fabien
authors.initials: F
authors.lastname: Zoulim
authors.affiliation: INSERM U1052, CNRS UMR_5286, Cancer Research Centre of Lyon (CRCL), 69008 Lyon, France; University of Lyon, Université Claude Bernard (UCBL), UMR_S1052, 69008 Lyon, France. Electronic address: david.durantel@inserm.fr.
authors.forename: David
authors.initials: D
authors.lastname: Durantel
mesh_terms: D015153:Blotting, Western; D002478:Cells, Cultured; D000071457:DEAD Box Protein 58 / Q000096:biosynthesis / Q000235:genetics*; D004279:DNA, Viral / Q000235:genetics*; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D006509:Hepatitis B / Q000235:genetics* / Q000378:metabolism / Q000821:virology; D006515:Hepatitis B virus / Q000235:genetics*; D022781:Hepatocytes / Q000378:metabolism / Q000473:pathology* / Q000821:virology; D006801:Humans; D060888:Real-Time Polymerase Chain Reaction; D018160:Receptors, Cytoplasmic and Nuclear; D011971:Receptors, Immunologic; D051193:Toll-Like Receptors / Q000096:biosynthesis / Q000235:genetics*; D014779:Virus Replication
chemical_list: D004279:DNA, Viral; D018160:Receptors, Cytoplasmic and Nuclear; D011971:Receptors, Immunologic; D051193:Toll-Like Receptors; C452820:RIGI protein, human; D000071457:DEAD Box Protein 58
keywords: Antiviral activity; Hepatitis B virus; Hepatocyte; Pathogen recognition receptor; Toll-like receptor