title: Immune hemolytic assay for identification of human anti-dsDNA antibodies with DNA-coated red blood cells as target cells.
abstract: A hemolytic assay was developed with the primary aim of being able to identify human lymphocytes producing anti-dsDNA antibodies found in patients with systemic lupus erythematosus (SLE). The coating of sheep red-blood cells with DNA was performed after precoating the cells with poly-L-lysine. The DNA-SRBC were lysed by anti-DNA antibodies from SLE sera, and the percent hemolysis was found to correlate with the anti-DNA activity demonstrated by the Farr assay (r = 0.87). Single-stranded DNA at the surface of the coated cells could be removed after digestion with nuclease S1. The effect of the digestion was verified by SLE serum specific for single-stranded DNA. With slight modifications, the target cells may be used to determine not only the titer of anti-DNA antibodies but also the complement-consumption and immunoglobulin classes of the anti-DNA antibodies.
authors.affiliation: Laboratory of Medical Immunology, State University Hospital (Rigshospitalet), Copenhagen, Denmark.
authors.forename: M K
authors.initials: MK
authors.lastname: Loftager
authors.forename: C
authors.initials: C
authors.lastname: Koch
authors.forename: P
authors.initials: P
authors.lastname: Hellung-Larsen
authors.forename: V
authors.initials: V
authors.lastname: Andersen
mesh_terms: D000937:Antigen-Antibody Reactions; D001323:Autoantibodies / Q000032:analysis*; D004247:DNA / Q000276:immunology*; D004720:Endonucleases / Q000494:pharmacology; D004912:Erythrocytes; D006461:Hemolysis; D006801:Humans; D066298:In Vitro Techniques; D008180:Lupus Erythematosus, Systemic / Q000276:immunology*; D015719:Single-Strand Specific DNA and RNA Endonucleases
chemical_list: D001323:Autoantibodies; D004247:DNA; D004720:Endonucleases; D015719:Single-Strand Specific DNA and RNA Endonucleases