title: Polyspecific binding of Escherichia coli beta-galactosidase by murine antibodies to DNA.
abstract: To characterize further polyspecific interactions of antibodies to DNA, the binding of sera from autoimmune MRL-lpr/lpr mice to Escherichia coli beta-galactosidase (beta-gal) was analyzed. This protein was selected for study because of preliminary observations that sera from autoimmune mice bound unexpectedly to cloned fusion protein constructions containing beta-gal. Using ELISA assays, sera from MRL-lpr/lpr mice demonstrated high levels of antibodies to both DNA and beta-gal, in titers significantly greater than those of BALB/c controls. Affinity chromatography using beta-gal-Sepharose demonstrated that antibodies enriched for anti-beta-gal activity bound both DNA as well as beta-gal, indicating the presence of a population of cross-reactive anti-DNA antibodies. Furthermore, anti-DNA mAb of MRL-lpr/lpr strain origin also bound beta-gal by ELISA, although these levels were lower than those to DNA. Together, these results extend the range of polyspecific binding of murine anti-DNA antibodies to bacterial proteins. They further suggest caution in the interpretation of immunoassays using fusion protein constructions containing beta-gal, especially with sera from autoimmune mice.
authors.affiliation: Medical Research Service, Durham VA Hospital, NC 27705.
authors.forename: D S
authors.initials: DS
authors.lastname: Pisetsky
authors.forename: J P
authors.initials: JP
authors.lastname: Grudier
mesh_terms: D000818:Animals; D000974:Antibodies, Antinuclear / Q000378:metabolism*; D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D001666:Binding Sites, Antibody; D003429:Cross Reactions; D004247:DNA / Q000276:immunology*; D004926:Escherichia coli / Q000201:enzymology* / Q000276:immunology; D005696:Galactosidases / Q000378:metabolism*; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D011993:Recombinant Fusion Proteins / Q000276:immunology / Q000378:metabolism; D001616:beta-Galactosidase / Q000276:immunology / Q000378:metabolism*
chemical_list: D000974:Antibodies, Antinuclear; D000911:Antibodies, Monoclonal; D011993:Recombinant Fusion Proteins; D004247:DNA; D005696:Galactosidases; D001616:beta-Galactosidase