Revisiting autoantibody profiles in systemic lupus erythematosus

To obtain more definitive assays of the spectrum of soluble autoantigens targeted by individual patients with systemic lupus erythematosus (SLE) and to determine whether the autoimmune response is restricted in specificity. Although there are many reports of a broad spectrum of autoantibody specificities in SLE, none has considered the diversity of autoantibody sets, which may more accurately describe the autoimmune response.

Sera of 68 patients with SLE were assayed for autoantibodies by ELISA and/or immunoprecipitation. Specificities were grouped into sets, including double stranded (ds) DNA and/or histone, U1 RNP and/or Sm, Ro and/or La, ribosomes, Ku, Ki, and others. An analysis was also performed of reported SLE autoantibody profiles.

The prevalences of autoantibody sets included: dsDNA and/or histone, 59%; U1 RNP and/or Sm, 40%; Ro and/or La, 41%; ribosomes, 4.4%; Ku, 4.4%; Ki, 2.9%. On average, autoantibody positive patients had 2-3 autoantibodies (median = 2) and about 2-3 autoantibody sets (median = 2), consistent with a retrospective analysis of past studies.

Immune dysregulation in SLE generally involves a multiplicity of autoantibody specificities. These data further support a model in which global immune dysregulation in SLE leads to organ-nonspecific autoimmunity against particular ubiquitous autoantigens.