[Responsiveness of a new parvovirus B19 antigen produced in baculovirus expression system to B19-specific IgG and IgM antibodies in every epidemic, 1968, 1980, 1987 and 1992 in Japan].

A new recombinant parvovirus B19 antigen was tested whether it was responsive to human serum antibodies in every epidemic year of erythema infectiosum for 25 years, because wild strains of B19 parvovirus were changeable genetically. The antigen was empty particles of both B19-VP1 and VP2 produced in baculovirus expression system. Specimens were 21 sera in 1968, 19 in 1980, 44 in 1987 and 33 in 1992, derived from 67 patients with erythema infectiosum, fever and/or non-specific exanthem and aplastic crisis in persons with hereditary spherocytosis. Each patient had been confirmed of B19 parvovirus infection by other methods as radio immunoassay and/or enzyme-linked immunosolvent assay for B19-IgG and IgM using other antigens and by detection of B19-genome DNA using the polymerase chain reaction. Days of the illness of every serum were confirmed including before infection to 216 days after onset. Sera from 23 patients with measles, Kawasaki disease and rubella were selected for controls, and those patients who had not been infected with B19 parvovirus. Tests were carried out by enzyme immunoassay, indirect method for IgG and IgM capture method. In a total of 103 specimens after onset of symptoms B19-IgG was positive in yearly specimens, and B19-IgM was also positive in all acute phase sera. B19-IgG in most of all sera was kept in peak level up to 216 days after onset. B19-IgM increased rapidly in acute phase and seemed to disappear within one to 5 months after onset. Thirty-seven specimens including 14 obtained at state before infection and 23 controls were completely negative for both B19-IgG and IgM.(ABSTRACT TRUNCATED AT 250 WORDS)