Use of a commercial line blot assay as a screening test for autoantibodies in inflammatory myopathies

Autoimmun Rev. 2009 Sep;9(1):58-61. doi: 10.1016/j.autrev.2009.03.005. Epub 2009 Mar 11.


Aims: To evaluate the clinical utility of a commercial immunoblot assay for the detection of myositis-specific autoantibodies.

Methods: Serum samples from 153 myositis patients and 77 disease controls were investigated. The commercial Euroline assay with seven autoantigens (Mi-2, Ku, PM-Scl, Jo-1, Pl-7, Pl-12 and SSA/Ro-52) was used according to the manufacturer s instructions, and supplemented with an anti-SRP strip. In a separate experiment analyses were performed at different temperatures. Results were recorded with densitometry.

Results: Anti-Jo-1 was found in 18 myositis and one systemic sclerosis patient. Antibodies against Mi-2 were found in 5 myositis patients, and eleven myositis patients had antibodies against PM-Scl. Four myositis patients showed anti-Pl-7 reactivity, whereas no patients had antibodies against Pl-12. Anti-Ku antibodies were found in 4 myositis and 2 primary Sjögren's syndrome patients. Anti-SRP was found in 8 myositis patients as well as in two disease controls. Antibodies against SSA/Ro52 ranged between 23-62% in all groups except juvenile dermatomyositis patients. Most autoantibody reactivities were clearly positive, only 11% (14/127) were borderline positive. Higher assay temperature increased antibody reactivities.

Conclusions: Except for anti-SSA/Ro-52 and anti-Ku the antibody reactivities were rather myositis-specific, supporting the use of this immunoblot assay. However, assay validation needs to be determined against other methods.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Autoantibodies / blood
  • Autoantigens / immunology*
  • Feasibility Studies
  • Female
  • Humans
  • Immunoblotting*
  • Lupus Erythematosus, Systemic / blood
  • Lupus Erythematosus, Systemic / diagnosis
  • Lupus Erythematosus, Systemic / immunology
  • Male
  • Middle Aged
  • Myositis / blood
  • Myositis / diagnosis*
  • Myositis / immunology
  • Scleroderma, Systemic / blood
  • Scleroderma, Systemic / diagnosis
  • Scleroderma, Systemic / immunology
  • Sensitivity and Specificity
  • Temperature


  • Autoantibodies
  • Autoantigens