Lupus autoantibodies to native DNA cross-react with the A and D SnRNP polypeptides.
Antibodies to native DNA (nDNA) in sera from patients with systemic lupus erythematosus have been found to frequently correlate with antibodies to the A and D SnRNP proteins measured in Western blot assays. 40 of 54 SLE (74.1%) sera with anti-nDNA bound to A and D proteins, while 9 of 113 sera (8%) without anti-nDNA bound the A and D proteins, P < 10(-8) by Fisher's exact test. Antibodies to nDNA correlated closely with anti-A and anti-D in seven of eight patients followed sequentially, r = 0.7865. Nine human polyclonal anti-nDNA populations were isolated from DNA cellulose columns. Seven reacted equally with A and D, and two reacted predominantly with D. Two of three murine monoclonal anti-DNA antibodies isolated from NZB/NZW F1 hybrid mice bound A and D equally in Western blot with a titer > 1/40,000. These reactions were directed to the unfolded A and D proteins measurable in Western blot since these monoclonals (and several of the human anti-nDNA populations) failed to react with native U1RNP in ELISA or in RNA immunoprecipitation experiments. These newly recognized cross reactions of anti-nDNA may amplify the immune response to DNA and be part of the original immunogenic drive.
Reichlin
M
M
Arthritis/Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City 73104.
Martin
A
A
Taylor-Albert
E
E
Tsuzaka
K
K
Zhang
W
W
Reichlin
M W
MW
Koren
E
E
Ebling
F M
FM
Tsao
B
B
Hahn
B H
BH
D000818:Animals; D000911:Antibodies, Monoclonal; D001323:Autoantibodies / Q000097:blood* / Q000302:isolation & purification; D015153:Blotting, Western; D002846:Chromatography, Affinity; D003429:Cross Reactions; D004247:DNA / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008815:Mice, Inbred Strains / Q000276:immunology; D008970:Molecular Weight; D017411:Ribonucleoproteins, Small Nuclear / Q000276:immunology*
D000911:Antibodies, Monoclonal; D001323:Autoantibodies; D017411:Ribonucleoproteins, Small Nuclear; D004247:DNA