title: Rubella reimmunization: comparative analysis of the immunoglobulin G response to rubella virus vaccine in previously seronegative and seropositive individuals.
abstract: Rubella virus (RV)-specific immunoglobulin G (IgG) antibodies were studied in military recruits undergoing unselected immunization with live attenuated measles, mumps, and rubella virus (MMR) vaccine. Three different whole-RV enzyme immunoassays (EIAs) and an epitope-specific EIA with a synthetic peptide (BCH-178c) representing a heutralization domain on the RV E1 envelope protein were used. Before vaccination, 84.2, 87.7, and 84.5% of the subjects tested (n = 399) were found to be seropositive (> 10 IU/ml or assay equivalent) by the three whole-RV EIAs, respectively, while only 82.5% were seropositive by the BCH-178c EIA. Although prevaccination seropositivity rates were similar for the whole-RV EIAs (sensitivity, 94 to 100%), many sera considered seropositive by the whole-RV EIAs had E1 peptide EIA antibody levels of < 10 IU/ml (sensitivity, 77.4 to 80.7%). One month after vaccination, 97.8, 97.2, and 93.5% of the subjects who were followed (n = 356) were seropositive by the three whole-RV EIAs, respectively, while 89% had BCH-178c peptide-specific IgG titers of > 10 IU/ml. After vaccination, depending on the assay used, up to 20.6% of initially seropositive individuals exhibited a greater than fourfold increase in RV-specific IgG, while up to 47.3% showed a greater than twofold increase. Increased antibody titers after vaccination (seroboosting) were most frequently associated with low levels of BCH-178c peptide-specific IgG before vaccination. RV protein-specific IgG was also studied by immunoblot assays in a subset (n = 56) of individuals receiving the MMR vaccine. Of these, 89.4 and 91.1% exhibited RV protein (E1, E2, and C protein)-specific IgG before and after vaccination, respectively. Seroboosting (two- to fourfold increase in EIA titers of individuals seropositive by the whole-RV EIA before vaccination) was usually accompanied by a shift in the IgG immunoblot pattern from a single (E1) to multiple (E1-E1, E1-C, or E1-E2-C) specificities, suggesting exposure of new epitopes as a result of viral replication.
authors.affiliation: Department of Pathology, University of British Columbia, Vancouver, Canada. leslie@wpog.childhosp.bc.ca
authors.forename: L A
authors.initials: LA
authors.lastname: Mitchell
authors.forename: M K
authors.initials: MK
authors.lastname: Ho
authors.forename: J E
authors.initials: JE
authors.lastname: Rogers
authors.forename: A J
authors.initials: AJ
authors.lastname: Tingle
authors.forename: R G
authors.initials: RG
authors.lastname: Marusyk
authors.forename: J M
authors.initials: JM
authors.lastname: Weber
authors.forename: P
authors.initials: P
authors.lastname: Duclos
authors.forename: M L
authors.initials: ML
authors.lastname: Tepper
authors.forename: M
authors.initials: M
authors.lastname: Lacroix
authors.forename: M
authors.initials: M
authors.lastname: Zrein
mesh_terms: D000293:Adolescent; D000328:Adult; D000914:Antibodies, Viral / Q000097:blood*; D002648:Child; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D012409:Rubella / Q000097:blood / Q000276:immunology / Q000517:prevention & control*; D012411:Rubella Vaccine / Q000276:immunology / Q000627:therapeutic use*; D012412:Rubella virus / Q000276:immunology*; D015164:Vaccines, Inactivated / Q000276:immunology / Q000627:therapeutic use
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G; D012411:Rubella Vaccine; D015164:Vaccines, Inactivated