Two anti-parvovirus B 19 IgM capture assays incorporating a mouse monoclonal antibody specific for B 19 viral capsid proteins VP 1 and VP 2

During an outbreak of parvovirus B 19 in 1989 in Northern Ireland, 7580 blood donors were screened for B 19 antigen. Two units screened positive, one of which was obtained for use as viral antigen. A monoclonal antibody (R92F6) made against this antigen was specific for B 19 capsid proteins VP 1 and VP 2. The monoclonal antibody was used in the development of 2 anti-B 19 IgM capture enzyme assays. These used a conventional substrate (O-phenylene diamine) and a chemiluminescent signal reagent. There was excellent concordance between the 2 assays. A total of 403 patients sera were tested and 65 sera were positive in each assay.