MORPHOLOGY AND ANTIGENICITY OF RECOMBINANT B19 PARVOVIRUS CAPSIDS EXPRESSED IN TRANSFECTED COS-7 CELLS

COS-7 cells transfected with parvovirus B19-simian virus 40 (SV40) hyb rid vectors have previously been shown to express B19 structural prote ins. In this study the morphology and antigenicity of B19 proteins exp ressed in these cells were investigated. At 84 h after transfection, a pproximately 10% of the COS-7 cells expressed B19 antigen, and the yie ld was equivalent to 2 x 10(3) to 2 x 10(5) B19 particles/transfected cell. The B19 proteins self-assembled into capsids that were morpholog ically and antigenically similar to native B19 virions, and could subs titute for native antigen in a B19 IgM assay. Recombinant capsids lack ing the recently described 11 kDa protein also resembled native virion s.