title: Virus attenuation after deletion of the cytomegalovirus Fc receptor gene is not due to antibody control.
abstract: The murine cytomegalovirus (MCMV) fcr-1 gene codes for a glycoprotein located at the surface of infected cells which strongly binds the Fc fragment of murine immunoglobulin G. To determine the biological significance of the fcr-1 gene during viral infection, we constructed MCMV fcr-1 deletion mutants and revertants. The fcr-1 gene was disrupted by insertion of the Escherichia coli lacZ gene. In another mutant, the marker gene was also deleted, by recombinase cre. As expected for its hypothetical role in immunoevasion, the infection of mice with fcr-1 deletion mutants resulted in significantly restricted replication in comparison with wild-type MCMV and revertant virus. In mutant mice lacking antibodies, however, the fcr-1 deletion mutants also replicated poorly. This demonstrated that the cell surface-expressed viral glycoprotein with FcR activity strongly modulates the virus-host interaction but that this biological function is not caused by the immunoglobulin binding property.
authors.affiliation: Max von Pettenkofer-Institut für Hygiene und Medizinische Mikrobiologie, University of Munich, Germany.
authors.forename: I
authors.initials: I
authors.lastname: Crnković-Mertens
authors.forename: M
authors.initials: M
authors.lastname: Messerle
authors.forename: I
authors.initials: I
authors.lastname: Milotić
authors.forename: U
authors.initials: U
authors.lastname: Szepan
authors.forename: N
authors.initials: N
authors.lastname: Kucić
authors.forename: A
authors.initials: A
authors.lastname: Krmpotić
authors.forename: S
authors.initials: S
authors.lastname: Jonjić
authors.forename: U H
authors.initials: UH
authors.lastname: Koszinowski
mesh_terms: D016475:3T3 Cells; D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology*; D017353:Gene Deletion; D006023:Glycoproteins / Q000276:immunology*; D007141:Immunoglobulin Fc Fragments / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology; D008562:Membrane Glycoproteins / Q000276:immunology*; D051379:Mice; D018146:Muromegalovirus / Q000235:genetics* / Q000276:immunology; D011961:Receptors, Fc / Q000235:genetics* / Q000276:immunology*; D014764:Viral Proteins
chemical_list: D000914:Antibodies, Viral; C110265:Fcr-1 protein, Mouse cytomegalovirus 1; D006023:Glycoproteins; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D008562:Membrane Glycoproteins; D011961:Receptors, Fc; D014764:Viral Proteins