Anti‐DNA Antibodies Induced by BK Virus Inoculations

Abstract

The ability of BK virus to induce anti-DNA antibodies in rabbits, and the ability of these antibodies to bind natural eukaryotic DNA and synthetic polynucleotides have been analysed. The specificity of the binding was assayed by inhibition of anti-dsDNA and -ssDNA ELISA tests with dsDNA, ssDNA, and synthetic single-stranded as well as double-stranded polynucleotides. The anti-dsDNA activity of two rabbit antisera was effectively inhibited by dsDNA and ssDNA and poly(dAdT)-poly(dAdT). The other nucleotide antigens produced relatively less inhibition. The anti-ssDNA binding was most efficiently inhibited by the homologous antigen, whereas inhibition by dsDNA only reached approximately 70% of the maximum as defined by ssDNA as inhibitor. This indicates the existence of a selective anti-ssDNA antibody population and a population recognizing both ssDNA and dsDNA within the sera. Cross-reaction of the induced anti-DNA antibodies with phospholipid antigens, such as cardiolipin, phosphatidylic acid, and bacterial cell surface, could not be demonstrated. We conclude that antibodies resulting from inoculation with BK virus specifically bind to dsDNA and ssDNA and possess a high affinity for the synthetic duplex poly(dAdT). In this way, they have some similarities with anti-DNA antibodies encountered in SLE (systemic lupus erythematosus) in both man and mouse.