Small molecule inhibition of hepatitis C virus E2 binding to CD81

Virology. 2003 Sep 15;314(1):371-80. doi: 10.1016/s0042-6822(03)00406-9.


The hepatitis C virus (HCV) is a causal agent of chronic liver infection, cirrhosis, and hepatocellular carcinoma infecting more than 170 million people. CD81 is a receptor for HCV envelope glycoprotein E2. Although the binding of HCV-E2 with CD81 is well documented the role of this interaction in the viral life cycle remains unclear. Host specificity and mutagenesis studies suggest that the helix D region of CD81 mediates binding to HCV-E2. Structural analysis of CD81 has enabled the synthesis of small molecules designed to mimic the space and hydrophobic features of the solvent-exposed face on helix D. Utilizing a novel bis-imidazole scaffold a series of over 100 compounds has been synthesized. Seven related, imidazole-based compounds were identified that inhibit binding of HCV-E2 to CD81. The inhibitory compounds have no short-term effect on cellular expression of CD81 or other tetraspanins, do not disrupt CD81 associations with other cell surface proteins, and bind reversibly to HCV-E2. These results provide an important proof of concept that CD81-based mimics can disrupt binding of HCV-E2 to CD81.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aminoimidazole Carboxamide / analogs & derivatives*
  • Aminoimidazole Carboxamide / chemical synthesis
  • Aminoimidazole Carboxamide / pharmacology
  • Antigens, CD / chemistry
  • Antigens, CD / metabolism*
  • Binding Sites / drug effects
  • Binding, Competitive
  • Cell Line
  • Hepacivirus / drug effects*
  • Hepacivirus / pathogenicity
  • Humans
  • Magnetic Resonance Spectroscopy
  • Membrane Proteins / chemistry
  • Membrane Proteins / metabolism*
  • Models, Molecular
  • Molecular Mimicry
  • Protein Binding / drug effects
  • Tetraspanin 28
  • Viral Envelope Proteins / genetics
  • Viral Envelope Proteins / metabolism*


  • Antigens, CD
  • CD81 protein, human
  • Membrane Proteins
  • Tetraspanin 28
  • Viral Envelope Proteins
  • glycoprotein E2, Hepatitis C virus
  • Aminoimidazole Carboxamide