Clinical features of anti-TIF1-α antibody-positive dermatomyositis patients are closely associated with coexistent dermatomyositis-specific autoantibodies and anti-TIF1-γ or anti-Mi-2 autoantibodies.

Abstract

OBJECTIVE:

Myositis-specific autoantibodies (MSAs), which characterize certain forms of inflammatory myopathy, are useful in the diagnosis and prediction of prognosis in DM/PM. Anti-transcriptional intermediary factor 1-α (TIF1-α) antibodies were recently reported to be associated with cancer-associated DM in conjunction with anti-TIF1-γ antibodies. This study aimed to identify a subset of DM patients who have anti-TIF1-α antibodies by using biotinylated recombinant proteins and to clarify the clinical and other serological features of DM patients with these antibodies.

METHODS:

Sera from 202 Japanese patients with CTDs, including 108 with DM and 20 healthy controls, were screened for anti-TIF1-α antibodies by our novel ELISAs. Positive sera were further examined by immunoprecipitation and also investigated for the detection of anti-TIF1-γ and anti-Mi-2 antibodies.

RESULTS:

Sera from 12 patients with DM were confirmed to be positive for anti-TIF1-α antibodies. None of the patients with other CTDs and none of the healthy controls had the antibodies. Seven anti-TIF1-α-positive patients simultaneously had anti-TIF1-γ antibodies and the other five had anti-Mi-2 antibodies, both of which are well known to be MSAs. These double-positive patients with anti-TIF1-α and anti-γ antibodies included three JDM and two cancer-associated adult DM patients, whereas all the double-positive patients with anti-TIF1-α and anti-Mi-2 antibodies were classical adult DM.

CONCLUSION:

Although MSAs have been regarded as mutually exclusive, anti-Mi-2 antibody-positive patients simultaneously have anti-TIF1-α antibodies. Anti-Mi-2 antibody-positive patients are associated with classical DM without cancer even with the simultaneous presence of anti-TIF1-α antibodies.

• Authors: Yoshinao Muro, Asuka Ishikawa, Kazumitsu Sugiura, Masashi Akiyama
• Journal: Rheumatology (Oxford, England) (Rheumatology (Oxford)) Vol. 51 Issue 8 Pg. 1508-13 (Aug 2012) ISSN: 1462-0332 [Electronic] England
• PMID: 22539482 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Autoantibodies
• Autoantigens
• Mi-2 antibodies
• Nuclear Proteins
• Recombinant Proteins
• TRIM33 protein, human
• Transcription Factors
• transcriptional intermediary factor 1

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Autoantibodies (blood, immunology)
• Autoantigens (immunology)
• Case-Control Studies
• Child
• Child, Preschool
• Dermatomyositis (immunology)
• Enzyme-Linked Immunosorbent Assay (methods)
• Female
• Humans
• Immunoprecipitation
• Infant
• Male
• Middle Aged
• Nuclear Proteins (immunology)
• Recombinant Proteins
• Transcription Factors (immunology)
• Young Adult