Anti-Nucleic Acid Antibodies in SLE—Clinical and Pathological Significance

Clinical significance of antibodies to double stranded DNA (dsDNA) for systemic lupus erythematosus (SLE)

In sera of patients with systemic lupus erythematosus (SLE) a wide variety of antibodies against nuclear antigens can be found, including antibodies to nucleic acids, histones and non-histone nuclear proteins. Among these, antibodies to double stranded DNA (dsDNA) appear to be mainly restricted to SLE. Yet, in daily practice one also finds patients that have antibodies to dsDNA during a long time ( greater than 5 years) but have not developed SLE. These anti-dsDNA positive non-SLE patients often fulfil several of the ARA criteria for SLE though one may not conclude that they form a specific clinical subset of SLE. It has often been tried to discriminate between clinical subsets of this heterogeneous disease by studying differences within the population of anti-dsDNA antibodies. Immunospecificity, complement-fixing ability, avidity, immunoglobulin (sub)class composition have all been the subject of different studies; yet, conclusions from these studies are often contradictory and more work will be necessary to elucidate this. The prognostic significance of anti-dsDNA levels in prospective studies has been proven valuable. A continuous increase in anti-dsDNA level correlates well with the appearance of an exacerbation of the disease. In other studies merely the amount of antibodies was found to be correlated with disease activity. Therapeutical consequences of these findings are still discutable. The role of anti-dsDNA antibodies in the pathogenesis of the disease is merely based on the above mentioned correlations and on the specificity of the antibodies to SLE. Questions regarding the etiology of SLE or the mere existence of anti-dsDNA antibodies in this kind of patients are unresolved.(ABSTRACT TRUNCATED AT 250 WORDS)