Differential effects of glycoprotein B epitope-specific antibodies on human cytomegalovirus-induced cell-cell fusion.
Attachment of, and cell-cell fusion induced by, human cytomegalovirus were studied in the presence of neutralizing monospecific antibodies against antigenic domains 1 (AD-1) or 2 (AD-2) of glycoprotein B (gB, gpUL55). Efficient inhibition of the virion-mediated fusion event was consistently observed for the human AD-2-specific antibody as determined by a reporter gene activation assay based on permissive astrocytoma cells. In contrast, antibodies directed against the major neutralizing gB epitope AD-1 reduced fusion only by 20-60 %. Virus attachment via heparan sulfate was unaffected by the antibodies under the conditions used. Virus receptor binding as examined by heparin treatment of adsorbed virus was significantly reduced only if the virus had been coated with the AD-2-specific antibody. Neutralization of virus infectivity by the AD-2-specific antibody thus seems most likely to result from interference with a receptor-binding event during initial virus-host cell interaction.
Gicklhorn
Dorothee
D
Institut für Virologie, Philipps-Universität Marburg, Robert-Koch-Straβe 17, 35037 Marburg, Germany.
Eickmann
Markus
M
Institut für Virologie, Philipps-Universität Marburg, Robert-Koch-Straβe 17, 35037 Marburg, Germany.
Meyer
Grit
G
Institut für Virologie, Philipps-Universität Marburg, Robert-Koch-Straβe 17, 35037 Marburg, Germany.
Ohlin
Mats
M
Department of Immunotechnology, Lund University, PO Box 7031, S-220 07 Lund, Sweden.
Radsak
Klaus
K
Institut für Virologie, Philipps-Universität Marburg, Robert-Koch-Straβe 17, 35037 Marburg, Germany.
D000911:Antibodies, Monoclonal / Q000276:immunology; D000914:Antibodies, Viral / Q000276:immunology*; D001254:Astrocytoma; D002459:Cell Fusion; D003587:Cytomegalovirus / Q000276:immunology* / Q000472:pathogenicity; D000939:Epitopes / Q000276:immunology*; D006801:Humans; D009500:Neutralization Tests; D014407:Tumor Cells, Cultured; D014759:Viral Envelope Proteins / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D000939:Epitopes; D014759:Viral Envelope Proteins; C040495:glycoprotein B, Simplexvirus