title: Thromboxane A2 synthase inhibitors prevent production of infectious hepatitis C virus in mice with humanized livers.
abstract: OBJECTIVE
  A 3-dimensional (3D) culture system for immortalized human hepatocytes (HuS-E/2 cells) recently was shown to support the lifecycle of blood-borne hepatitis C virus (HCV). We used this system to identify proteins that are active during the HCV lifecycle under 3D culture conditions.
  
  
  METHODS
  We compared gene expression profiles of HuS-E/2 cells cultured under 2-dimensional and 3D conditions. We identified signaling pathways that were activated differentially in the cells, and analyzed their functions in the HCV lifecycle using a recombinant HCV-producing cell-culture system, with small interfering RNAs and chemical reagents. We investigated the effects of anti-HCV reagents that altered these signaling pathways in mice with humanized livers (carrying human hepatocytes).
  
  
  RESULTS
  Microarray analysis showed that cells cultured under 2-dimensional vs 3D conditions expressed different levels of messenger RNAs encoding prostaglandin synthases. Small interfering RNA-mediated knockdown of thromboxane A2 synthase (TXAS) and incubation of hepatocytes with a TXAS inhibitor showed that this enzyme is required for production of infectious HCV, but does not affect replication of the HCV genome or particle release. The TXAS inhibitor and a prostaglandin I2 receptor agonist, which has effects that are opposite those of thromboxane A2, reduced serum levels of HCV and inhibited the infection of human hepatocytes by blood-borne HCV in mice.
  
  
  CONCLUSIONS
  An inhibitor of the prostaglandin synthase TXAS inhibits production of infectious HCV particles in cultured hepatocytes and HCV infection of hepatocytes in mice with humanized livers. It therefore might be therapeutic for HCV infection.
authors.affiliation: Institute of Virus Research, Kyoto University, Kyoto, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Abe
authors.forename: Hussein Hassan
authors.initials: HH
authors.lastname: Aly
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Hiraga
authors.forename: Michio
authors.initials: M
authors.lastname: Imamura
authors.forename: Takaji
authors.initials: T
authors.lastname: Wakita
authors.forename: Kunitada
authors.initials: K
authors.lastname: Shimotohno
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Chayama
authors.forename: Makoto
authors.initials: M
authors.lastname: Hijikata
mesh_terms: D000818:Animals; D001483:Base Sequence; D018929:Cell Culture Techniques; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D004791:Enzyme Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D019084:Fluorescent Antibody Technique, Indirect; D016174:Hepacivirus / Q000187:drug effects / Q000201:enzymology* / Q000472:pathogenicity; D006526:Hepatitis C / Q000517:prevention & control* / Q000821:virology; D022781:Hepatocytes / Q000821:virology*; D006801:Humans; D008689:Methacrylates / Q000494:pharmacology / Q000627:therapeutic use*; D051379:Mice; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013930:Thromboxane-A Synthase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D014764:Viral Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: D004791:Enzyme Inhibitors; D008689:Methacrylates; D014764:Viral Proteins; D013930:Thromboxane-A Synthase; C034364:ozagrel
keywords: 2-dimensional; 2D; 3-dimensional; 3D; AAC; Antiviral Drug; COX; HCV; HCVcc; IP; Infectious Virus Particle; LD; Lipid Mediator; PG; PGIS; RT-PCR; TP; TXA(2); TXAS; TXB(2); arachidonic acid cascade; bbHCV; blood-borne hepatitis C virus; cAMP; cyclic adenosine monophosphate; cyclooxygenase; hepatitis C virus; hepatitis C virus from cell culture; lipid droplet; mRNA; messenger RNA; prostaglandin; prostaglandin I(2) receptor; prostaglandin I(2) synthase; qRT-PCR; quantitative reverse-transcription polymerase chain reaction; reverse-transcription polymerase chain reaction; siRNA; small interfering RNA; thromboxane A(2); thromboxane A(2) receptor; thromboxane A(2) synthase; thromboxane B(2)