Fig. 2
Detection of cross-reactivity in affinity-purified pp65422-439-specific IgG in serum from patients with systemic lupus erythematosus (SLE). a Immunoblot analysis with serum from patients with SLE, healthy controls and anti-pp65422-439 antibody from ten pooled SLE-double-stranded DNA (SLE-dsDNA(+) or SLE-dsDNA(-)) serum against human cytomegalovirus (HCMV)pp65. We used 100× diluted serum from patients with SLE or healthy controls and anti-His-tag antibody as positive and negative controls. Molecular mass markers (kD) are shown on the left. MW molecular weight, kDa kilodalton. b-c ELISA for anti-pp65422-439 and anti-dsDNA activity: 100× diluted normal serum and 3 μg anti-pp65422-439 antibody from SLE-dsDNA(+) or SLE-dsDNA(-) sera were used. For the competitive inhibitory assay, 1 μg/well of pp65422-439 or dsDNA was used. d Representatives of C. luciliae stain by 100× diluted serum from SLE-dsDNA(+) (d1) or healthy control and anti-pp65422-439 antibody (d2) from SLE-dsDNA(+) (d3) or SLE-dsDNA(-) (d4) serum. White arrowheads indicate the positive stains. e HEp-2 substrate slides were used for detection of anti-nuclear antibodies. Patterns of speckle (e4) and nucleosome/chromatin (e2, e5) stains were revealed by anti-pp65422-439 antibody from SLE-dsDNA(+) or SLE-dsDNA(-) serum. Nuclear reactivity was not observed from 100× diluted normal serum (e3, e6). White arrowheads indicate the patterns of nuclear response. These results are representative of triplicated experiments. O.D. optical density