title: Anti-Klebsiella K30 phospholipid antibodies in systemic lupus erythematosus: antigen cross-reactions and idiotypic sharing with antibodies to DNA and Klebsiella K30 polysaccharide.
abstract: Patients with systemic lupus erythematosus were examined for the presence of serum antibodies reactive with phospholipids (PL) extracted from the membranes of Klebsiella K30 (K30PL). Affinity-purified anti-K30PL antibodies were tested for their ability to cross-react with other PL antigens or DNA and for the presence of idiotypic markers known to be associated with anti-DNA antibodies or antibodies to Klebsiella K30 polysaccharide (K30p). Affinity-purified antibodies to K30PL, phosphatidylserine (PS), or phosphatidylinositol (PL) uniformly cross-reacted with each other. Analysis of the PL preparations by thin-layer chromatography and reversed-phase high-performance liquid chromatography (HPLC) showed the presence of several components. Lupus sera reacted with one component mainly in the HPLC-fractionated K30PL preparation, although this component appeared to be present in the other PL preparations. Direct-binding and inhibition studies showed that affinity-purified antibodies to the K30PL extract, PS, or PI reacted poorly with DNA. However, the anti-K30PL antibodies possessed a prominent anti-DNA idiotypic marker (AM Id) in 61% of the patients and an anti-K30p idiotypic marker (SP Id) in 94% of the patients. The results thus show that anti-K30PL antibodies are idiotypically related to anti-DNA and anti-K30p antibody subpopulations, although they do not share the same antigen-binding characteristics.
authors.affiliation: University of Edinburgh, Department of Veterinary Pathology, UK.
authors.forename: G D
authors.initials: GD
authors.lastname: Harkiss
authors.forename: F M
authors.initials: FM
authors.lastname: Hendrie
authors.forename: D
authors.initials: D
authors.lastname: Thompson
mesh_terms: D000974:Antibodies, Antinuclear / Q000032:analysis*; D000907:Antibodies, Bacterial / Q000032:analysis*; D000918:Antibody Specificity; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007130:Immunoglobulin Idiotypes / Q000032:analysis*; D007709:Klebsiella / Q000032:analysis / Q000276:immunology*; D008180:Lupus Erythematosus, Systemic / Q000276:immunology* / Q000382:microbiology; D010743:Phospholipids / Q000276:immunology* / Q000302:isolation & purification; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D013057:Spectrum Analysis
chemical_list: D000974:Antibodies, Antinuclear; D000907:Antibodies, Bacterial; D007130:Immunoglobulin Idiotypes; D010743:Phospholipids; D011135:Polysaccharides, Bacterial