• Clinical science

Antibody diagnosis of autoimmune diseases


Antibody diagnostics play a vital role in the differential diagnosis of autoimmune diseases. Many of these autoantibodies can be differentiated into antibodies against nuclear antigens (ANAs) and antibodies against cytoplasmic antigens (ANCAs). Although both of these antibodies are detectable in numerous autoimmune diseases, elevated ANAs are typical for connective tissue diseases and elevated ANCAs for vasculitis. Diagnosis of individual conditions can be further supported by detecting disease-specific ANAs or ANCAs, such as anti-dsDNA in systemic lupus erythematosus or c-ANCA in Wegener's granulomatosis.

Antinuclear antibodies (ANAs)

  • Brief description
    • ANAs are comprised of numerous antibodies against specific nuclear antigens.
    • In addition, ANAs include autoantibodies against DNA and histones.
    • ANAs were previously further classified into ENA (extractable nuclear antigen antibodies).
      • ANAs specifically target antigens within the nucleus.
      • ANAs are determined via a standardized immunofluorescence assay based on the pattern of fluorescence that is produced.
  • Assessment
Connective tissue diseases

Specific ANA

Other autoantibodies

Systemic lupus erythematosus (SLE)

Systemic sclerosis (scleroderma)

Sjögren syndrome

Polymyositis and dermatomyositis

  • Anti-Jo1
  • Anti-Mi2
  • RF

Mixed connective tissue disease

  • Anti-U1 RNP
  • RF


Antineutrophil cytoplasmic antibodies (ANCAs)

Specific ANCA Diseases
(Proteinase-3 antibody)
(Myeloperoxidase antibody)
atypical p-ANCA