Human cytomegalovirus glycoprotein H/glycoprotein L complex modulates fusion-from-without

J Gen Virol. 1998 Apr;79 ( Pt 4):855-65. doi: 10.1099/0022-1317-79-4-855.


Glycoprotein H/glycoprotein L (gH/gL) complexes of herpesviruses are required for fusion of infecting virions with host cell membranes. In human cytomegalovirus (HCMV), neutralizing monoclonal antibodies (MAb) specific for gH inhibit the transfer of a fluorescent probe to the host cell from labelled virus particles. In similar fashion, in the present study, neutralizing gH-specific MAb inhibited HCMV-induced fusion-from-without in monolayers of both human embryonic fibroblasts and continuous astrocytoma cells (U373). No fusion was detected in cells co-infected with defective recombinant adenovirus vectors that elicited high-level expression of gH and gL, indicating that surface-expressed gH was not intrinsically fusogenic. However, when such cells were superinfected with HCMV that gave fusion-from-without, the resulting cell-to-cell fusion was considerably enhanced. Thus, under our experimental conditions, gH/gL on the cell surface functioned to increase membrane fusion once this was initiated by other components in the virus envelope.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoviridae / genetics
  • Antibodies, Monoclonal / pharmacology
  • Base Sequence
  • Cells, Cultured
  • Cytomegalovirus / genetics
  • Cytomegalovirus / pathogenicity*
  • Cytomegalovirus / physiology
  • DNA Primers / genetics
  • Dactinomycin / pharmacology
  • Defective Viruses / genetics
  • Humans
  • Membrane Fusion / drug effects
  • Membrane Fusion / physiology*
  • Polymerase Chain Reaction
  • Recombination, Genetic
  • Viral Envelope Proteins / genetics
  • Viral Envelope Proteins / immunology
  • Viral Envelope Proteins / physiology*


  • Antibodies, Monoclonal
  • DNA Primers
  • Viral Envelope Proteins
  • glycoprotein H, Cytomegalovirus
  • glycoprotein H, Human cytomegalovirus
  • glycoprotein L, Human herpesvirus 1
  • Dactinomycin