Antiviral effect of the heparan sulfate mimetic, PI-88, against dengue and encephalitic flaviviruses

Antiviral Res. 2006 Jan;69(1):31-8. doi: 10.1016/j.antiviral.2005.08.006. Epub 2005 Nov 10.


Many viruses, including flaviviruses, display affinity for cell surface heparan sulfate (HS) proteoglycans with biological relevance in virus attachment/entry. This raises the possibility of the application of HS mimetics in antiviral therapy. We have evaluated the antiviral effect of the sulfated polysaccharides, suramin, pentosan polysulfate (PPS) and PI-88, which are currently approved or in trial for clinical use, against dengue virus (DEN) and the encephalitic flaviviruses, Japanese encephalitis virus, West Nile virus, and Murray Valley encephalitis virus. A flow cytometry-based method for the measurement of inhibition of virus infectivity was developed, which showed the in vitro antiviral activity of the three compounds, albeit with differences in efficiency which were virus-dependent. The 50% effective concentration (EC(50)) values for DEN inhibition were in the order: PPS<suramin<PI-88, and for Japanese encephalitis virus, PPS<PI-88<or=suramin. Heparin inhibited the DEN infectivity 30-fold more efficiently than the best of the test compounds, which was not the case for encephalitic flaviviruses. The in vitro anti-flaviviral effectiveness of the HS mimetics did not reliably predict their in vivo therapeutic activity. In mouse models for DEN and flaviviral encephalitis, only PI-88 demonstrated a significant beneficial effect in disease outcome.

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Antiviral Agents / chemistry
  • Antiviral Agents / pharmacology*
  • Antiviral Agents / therapeutic use
  • Cell Line
  • Dengue / drug therapy*
  • Dengue Virus / drug effects*
  • Disease Models, Animal
  • Drug Evaluation, Preclinical
  • Encephalitis Viruses, Japanese / drug effects*
  • Encephalitis, Arbovirus / drug therapy
  • Female
  • Flavivirus Infections / drug therapy
  • Heparitin Sulfate / pharmacology*
  • Heparitin Sulfate / therapeutic use
  • Injections, Intraperitoneal
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Oligosaccharides / chemistry
  • Oligosaccharides / pharmacology*
  • Oligosaccharides / therapeutic use
  • Pentosan Sulfuric Polyester / chemistry
  • Pentosan Sulfuric Polyester / pharmacology
  • Pentosan Sulfuric Polyester / therapeutic use
  • Suramin / chemistry
  • Suramin / pharmacology
  • Suramin / therapeutic use
  • Treatment Outcome


  • Antiviral Agents
  • Oligosaccharides
  • phosphomannopentaose sulfate
  • Pentosan Sulfuric Polyester
  • Suramin
  • Heparitin Sulfate