Dataset Information

Cytosolic 5'-Nucleotidase 1A As a Target of Circulating Autoantibodies in Autoimmune Diseases.

ABSTRACT: OBJECTIVE:Prior investigations demonstrated that autoantibodies recognizing cytosolic 5'-nucleotidase 1A (NT5C1A) are found in 33-76% of patients with inclusion body myositis (IBM) but are observed only rarely in patients with polymyositis (PM). Thus, anti-NT5C1A may help distinguish IBM from PM. Although 4-21% of patients with dermatomyositis (DM) were shown to be anti-NT5C1A antibody positive, the clinical features of anti-NT5C1A-positive patients with DM have not been described. Furthermore, the prevalence of anti-NT5C1A antibodies in other rheumatic conditions has not been reported. This study was undertaken to define the prevalence and clinical features of anti-NT5C1A-positive patients with DM, PM, IBM, or other systemic autoimmune diseases. METHODS:We screened for anti-NT5C1A autoantibodies in patients with IBM, DM, PM, Sjögren's syndrome (SS), or systemic lupus erythematosus (SLE) and in healthy volunteers. Clinical characteristics were compared between patients who were anti-NT5C1A positive and those who were anti-NT5C1A negative. RESULTS:Anti-NT5C1A autoantibodies were detected in 71 (61%) of 117 patients with IBM, 2 (5%) of 42 patients with PM, 2 (5%) of 42 healthy volunteers, 24 (15%) of 159 patients with DM, 10 (23%) of 44 patients with SS, and 13 (14%) of 96 patients with SLE. No anti-NT5C1A antibody-positive patients with SS or SLE had muscle involvement. Anti-NT5C1A-positive patients with IBM had a lower prevalence of rimmed vacuoles (62% versus 83% of antibody-negative patients; P?=?0.02). No differences in the clinical characteristics of antibody-positive and antibody-negative patients with DM, SS, or SLE were observed. CONCLUSION:Anti-NT5C1A is a common target of circulating autoantibodies, especially in IBM but also in several different autoimmune diseases. In SLE and SS, anti-NT5C1A autoreactivity is not associated with muscle disease.

SUBMITTER: Lloyd TE

PROVIDER: S-EPMC4887848 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Cytosolic 5'-Nucleotidase 1A As a Target of Circulating Autoantibodies in Autoimmune Diseases.

Lloyd Thomas E TE Christopher-Stine Lisa L Pinal-Fernandez Iago I Tiniakou Eleni E Petri Michelle M Baer Alan A Danoff Sonye K SK Pak Katherine K Casciola-Rosen Livia A LA Mammen Andrew L AL

Arthritis care & research 20160101 1

<h4>Objective</h4>Prior investigations demonstrated that autoantibodies recognizing cytosolic 5'-nucleotidase 1A (NT5C1A) are found in 33-76% of patients with inclusion body myositis (IBM) but are observed only rarely in patients with polymyositis (PM). Thus, anti-NT5C1A may help distinguish IBM from PM. Although 4-21% of patients with dermatomyositis (DM) were shown to be anti-NT5C1A antibody positive, the clinical features of anti-NT5C1A-positive patients with DM have not been described. Furth ...[more]

PMID: 25892010

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Dataset Information

Cytosolic 5'-Nucleotidase 1A As a Target of Circulating Autoantibodies in Autoimmune Diseases.

Publications

Cytosolic 5'-Nucleotidase 1A As a Target of Circulating Autoantibodies in Autoimmune Diseases.

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