IgA and IgG autoantibodies against alpha-fodrin as markers for Sjögren's syndrome. Systemic lupus erythematosus

J Rheumatol. 2000 Nov;27(11):2617-20.

Abstract

Objective: To determine the prevalence of IgA and IgG autoantibodies against alpha-fodrin in patients with primary and secondary Sjögren's syndrome (SS) and controls.

Methods: An ELISA detecting IgA and IgG antibodies against alpha-fodrin was developed. We examined the prevalence of IgA and IgG antibodies against alpha-fodrin in patients with primary and secondary SS, systemic lupus erythematosus (SLE), and rheumatoid arthritis (RA) and blood donors.

Results: IgA antibodies against alpha-fodrin were detected in 64% of patients with primary SS (n = 85), 47% of patients with secondary SS and SLE (n = 15), and 86% of patients with secondary SS and RA (n = 7). IgA autoantibodies against alpha-fodrin were detected in only one of 160 sera obtained from blood donors and in one of 50 and 2 of 12 sera obtained from SLE and RA patients without sicca syndrome, respectively. The prevalence of IgG antibodies against alpha-fodrin in SS was lower: they were detected in 55% of sera obtained from patients with primary SS, 40% of patients with secondary SS and SLE, and in 43% of patients with secondary SS and RA. Three of 160 sera from blood donors and one of 50 and 5 of 12 sera from SLE and RA patients without sicca syndrome, respectively, contained IgG antibodies against alpha-fodrin.

Conclusion: IgA rather than IgG antibodies against alpha-fodrin are specific for and frequently observed in primary and secondary SS and are useful markers for this autoimmune disorder.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Arthritis, Rheumatoid / complications
  • Arthritis, Rheumatoid / immunology
  • Autoantibodies / analysis*
  • Biomarkers
  • Blood Donors
  • Carrier Proteins / immunology*
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Humans
  • Immunoglobulin A / analysis*
  • Immunoglobulin G / analysis*
  • Lupus Erythematosus, Systemic / complications
  • Lupus Erythematosus, Systemic / immunology
  • Male
  • Microfilament Proteins / immunology*
  • Middle Aged
  • Sjogren's Syndrome / complications
  • Sjogren's Syndrome / immunology*

Substances

  • Autoantibodies
  • Biomarkers
  • Carrier Proteins
  • Immunoglobulin A
  • Immunoglobulin G
  • Microfilament Proteins
  • fodrin