Autoantibodies to alpha-fodrin in primary Sjögren's syndrome and SLE detected by an in vitro transcription and translation assay

Clin Exp Rheumatol. Jan-Feb 2003;21(1):49-56.

Abstract

Objective: To investigate the prevalence of alpha-fodrin autoantibodies in primary Sjögren's syndrome (SS) and systemic lupus erythematosus (SLE) with and without secondary SS, using an in vitro transcription and translation assay (ITT).

Methods: cDNA encoding JS-1, the amino-terminal portion of alpha-fodrin, was used for ITT. Immunoprecipitation was performed with sera from 56 primary SS patients and 67 SLE patients, 14 with and 53 without secondary SS. Correlations to RF, ANA, anti-dsDNA, anti-SS-A and anti-SS-B antibodies, hypergammaglobulinemia, labial salivary gland biopsy grade, extraglandular manifestations and a modified SLE disease activity index (mSLEDAI) were made.

Results: Autoantibodies against alpha-fodrin were detected in 16/56 (29%) of primary SS patients and in 25/53 (47%) of sera from SLE patients without secondary SS. In SLE patients with secondary SS the prevalence was 3/14 (21%). None of the blood donors showed alpha-fodrin reactivity. Correlations were found to RF, ANA, anti-dsDNA antibodies and a positive mSLEDAI score.

Conclusion: The frequency of alpha-fodrin autoantibodies detected by this method is similar in sera from primary SS patients and SLE patients with or without secondary SS. The presence of alpha-fodrin autoantibodies seems to reflect non-organ-specific autoimmunity in primary SS and SLE and to be of limited discriminating value.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Autoantibodies / analysis*
  • Biological Assay
  • Biomarkers / analysis
  • Carrier Proteins / genetics
  • Carrier Proteins / immunology*
  • Cell Line
  • DNA, Complementary / analysis
  • Female
  • Humans
  • In Vitro Techniques
  • Lupus Erythematosus, Systemic / blood
  • Lupus Erythematosus, Systemic / immunology*
  • Lupus Erythematosus, Systemic / physiopathology
  • Male
  • Microfilament Proteins / genetics
  • Microfilament Proteins / immunology*
  • Middle Aged
  • Precipitin Tests
  • Protein Biosynthesis
  • Rheumatoid Factor / blood
  • Severity of Illness Index
  • Sjogren's Syndrome / blood
  • Sjogren's Syndrome / immunology*
  • Sjogren's Syndrome / physiopathology
  • Transcription, Genetic

Substances

  • Autoantibodies
  • Biomarkers
  • Carrier Proteins
  • DNA, Complementary
  • Microfilament Proteins
  • fodrin
  • Rheumatoid Factor