GENERATION OF NEUTRALIZING ANTI-B19 PARVOVIRUS HUMAN MONOCLONAL-ANTIBODIES FROM PATIENTS INFECTED WITH HUMAN-IMMUNODEFICIENCY-VIRUS

The prevalence of IgG antibodies to human B19 parvovirus (anti-B19) is elevated in individuals infected with human immunodeficiency virus (H IV), especially during the later stages of HIV infection. In subjects with high titers of IgG anti-B19, 86% (19 of 22) had circulating B cel ls producing anti-B19. Immortalization of these cells with Epstein-Bar r virus and generation of heterohybridomas by fusion with a mouse x hu man heteromyeloma resulted in the production of two cell lines produci ng IgG1kappa monoclonal antibodies (MAbs). Both of these MAbs were spe cific for conformational epitopes on the VP2 capsid protein of B19 par vovirus and both were capable of neutralizing 50% of the viral infecti vity in a human erythroid colony-forming unit assay at less-than-or-eq ual-to 1 mug of MAb/mL. These human MAbs are potentially useful in the treatment of acute B19 parvovirus infection.