title: Detection of human parvovirus B19-specific IgM and IgG antibodies using a recombinant viral VP1 antigen expressed in insect cells and estimation of time of infection by testing for antibody avidity.
abstract: Sera from patients with symptoms of recent human parvovirus B19 (B19) infection were tested for B19-specific IgM in an immunofluorescence assay (IFA) using insect cells expressing B19 recombinant VP1 coat protein as an antigen. A highly significant correlation (P < 0.001) was found between titres obtained in the IgM IFA and the units obtained in an IgM antibody-capture RIA using plasma derived native B19 antigen. An IgG IFA using the recombinant antigen was performed on 57 sera and the antibody avidity determined. There was a highly significant correlation (P < 0.001) between the relative amounts of low avidity B19-specific IgG antibodies and time after onset of illness. This finding allows the detection of IgG to be used for diagnosing acute infection.
authors.affiliation: Clinical Microbiology and Public Health Laboratory, Addenbrooke's Hospital, Cambridge, UK.
authors.forename: J J
authors.initials: JJ
authors.lastname: Gray
authors.forename: B J
authors.initials: BJ
authors.lastname: Cohen
authors.forename: U
authors.initials: U
authors.lastname: Desselberger
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D000915:Antibody Affinity; D000956:Antigens, Viral / Q000276:immunology*; D002213:Capsid / Q000276:immunology*; D036022:Capsid Proteins; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D016731:Erythema Infectiosum / Q000097:blood / Q000276:immunology*; D005455:Fluorescent Antibody Technique; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D007075:Immunoglobulin M / Q000097:blood*; D007313:Insecta; D016732:Parvovirus B19, Human / Q000276:immunology*; D011863:Radioimmunoassay; D011993:Recombinant Fusion Proteins / Q000276:immunology*; D012217:Rheumatoid Factor / Q000097:blood; D014777:Virus Diseases / Q000097:blood / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D036022:Capsid Proteins; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D011993:Recombinant Fusion Proteins; D012217:Rheumatoid Factor