Anti-nuclear antibody

Anti-nuclear antibodies (ANAs, also known as anti-nuclear factor or ANF) are detected in a large group of autoimmune disorders. The presence of ANA is indicative of lupus erythematosus, though they also appear in some other auto-immune diseases such as Sjögren's syndrome, rheumatoid arthritis, autoimmune hepatitis, scleroderma and dermatomyositis, and various non-rheumatological conditions associated with tissue damage.

Following detection of a high titer of ANAs (e.g. 1:160), various subtypes are determined (Kavanaugh et al 2000). This is nowadays ususally done on cells of the HEp-2 cell line. Examples include:

• Anti-ENA (extractable nuclear antigen)
• Anti-dsDNA (double-stranded DNA)
• Anti-Jo (SS-A)
• Anti-Ro (SS-B)
• Anti-Sm (Smith antigen)
• Anti-nRNP (nuclear ribonucleoproteins)
• Anti-Scl-70
• Anti-topoisomerase I
• Anti-centromere

History

The LE cell was discovered in bone marrow in 1948 by Hargraves et al. This was the first indication that processes affecting the cell nucleus were responsible for lupus erythematosus (LE). In the 1950s, progressively more sensitive and specific ANA serology tests became available.

See also

• Rheumatoid factor
• Anti-neutrophil cytoplasmic antibody (ANCA)

Reference

• Hargraves M, Richmond H, Morton R. Presentation of two bone marrow components, the tart cell and the LE cell. Mayo Clin Proc 1948;27:25–28.
• Kavanaugh A, Tomar R, Reveille J, Solomon DH, Homburger HA. Guidelines for clinical use of the antinuclear antibody test and tests for specific autoantibodies to nuclear antigens. American College of Pathologists. Arch Pathol Lab Med 2000;124:71-81. PMID 10629135.