Identification of connective tissue disease autoantibodies and a novel autoantibody anti-annexin A11 in patients with "idiopathic" interstitial lung disease.

Background: Autoantibodies are a hallmark feature of Connective Tissue Diseases (CTD). Their presence in patients with idiopathic interstitial lung disease (ILD) may suggest covert CTD. We aimed to determine the prevalence of CTD autoantibodies in patients diagnosed with idiopathic ILD.

The reliability of immunoassays to detect autoantibodies in patients with myositis is dependent on autoantibody specificity.

Objectives: In order to address the reliability of commercial assays to identify myositis-specific and -associated autoantibodies, we aimed to compare the results of two commercial immunoassays with the results obtained by protein immunoprecipitation.

Methods: Autoantibody status was determined using radio-labelled protein immunoprecipitation for patients referred to our laboratory for myositis autoantibody characterization. For each autoantibody of interest, the sera from 25 different patients were analysed by line blot (Euroline Myositis Antigen Profile 4, EuroImmun, Lübeck, Germany) and dot blot (D-Tek BlueDiver, Diagnostic Technology, Belrose, NSW, Australia).

Focused HLA analysis in Caucasians with myositis identifies significant associations with autoantibody subgroups.

Objectives: Idiopathic inflammatory myopathies (IIM) are a spectrum of rare autoimmune diseases characterised clinically by muscle weakness and heterogeneous systemic organ involvement. The strongest genetic risk is within the major histocompatibility complex (MHC). Since autoantibody presence defines specific clinical subgroups of IIM, we aimed to correlate serotype and genotype, to identify novel risk variants in the MHC region that co-occur with IIM autoantibodies.

The performance of the European League Against Rheumatism/American College of Rheumatology idiopathic inflammatory myopathies classification criteria in an expert-defined 10 year incident cohort.

Objectives: To assess the performance of the EULAR/ACR idiopathic inflammatory myopathies (IIMs) classification criteria in a cohort of incident IIM cases and examine how criteria-assigned IIM subtype correlates with expert opinion.

Methods: Adults with newly diagnosed IIM attending Salford Royal NHS Foundation Trust were identified over a 10 year period. A retrospective review of all putative cases was performed and those fulfilling a consensus expert opinion diagnosis of IIM were included.

Investigation of myositis and scleroderma specific autoantibodies in patients with lung cancer.

Background: The close temporal association between onset of some connective tissue diseases and cancer suggests a paraneoplastic association. Adult patients with scleroderma with anti-RNA polymerase III autoantibodies and adult patients with dermatomyositis with anti-transcriptional intermediary factor 1 (anti-TIF1) or anti-nuclear matrix protein 2 (anti-NXP2) autoantibodies have a significantly increased risk of developing cancer. Autoantibodies may serve as biomarkers for early detection of cancer and also could be relevant for prediction of responses to immune therapies.

Presence of anti-eukaryotic initiation factor-2B, anti-RuvBL1/2 and anti-synthetase antibodies in patients with anti-nuclear antibody negative systemic sclerosis.

Objectives: Autoantibodies targeting ubiquitously expressed nuclear antigens can be identified in most patients with SSc. Cytoplasmic autoantibodies (in otherwise ANA-negative sera) targeting eukaryotic initiation factor-2B (anti-eIF2B) have recently been identified in SSc with clinical associations to dcSSc disease and interstitial lung disease (ILD), although the majority of samples originated from a tertiary SSc-ILD centre. We investigated the prevalence and clinical associations of recently described SSc-specific (including anti-eIF2B) and other cytoplasmic autoantibodies in ANA-negative sera obtained from a large representative SSc cohort.

The EuroMyositis registry: an international collaborative tool to facilitate myositis research.

Aims: The EuroMyositis Registry facilitates collaboration across the idiopathic inflammatory myopathy (IIM) research community. This inaugural report examines pooled Registry data.

Methods: Cross-sectional analysis of IIM cases from 11 countries was performed.

Autoantibodies in juvenile-onset myositis: Their diagnostic value and associated clinical phenotype in a large UK cohort.

Objectives: Juvenile myositis is a rare and heterogeneous disease. Diagnosis is often difficult but early treatment is important in reducing the risk of associated morbidity and poor outcomes. Myositis specific autoantibodies have been described in both juvenile and adult patients with myositis and can be helpful in dividing patients into clinically homogenous groups.

Anti-HMGCR Autoantibodies in Juvenile Idiopathic Inflammatory Myopathies Identify a Rare but Clinically Important Subset of Patients.

Objective: We aimed to establish the prevalence and clinical associations of anti-HMG-CoA-reductase (anti-HMGCR) in a large UK cohort with juvenile myositis.

Methods: There were 381 patients investigated for anti-HMGCR using ELISA.

Results: Anti-HMGCR autoantibodies were detected in 4 patients (1%).

Brief Report: Anti-Eukaryotic Initiation Factor 2B Autoantibodies Are Associated With Interstitial Lung Disease in Patients With Systemic Sclerosis.

Objective: To investigate novel systemic sclerosis (SSc) autoantibodies in autoantibody-negative patients and establish clinical associations.

Methods: Serum samples and clinical data for 548 patients with SSc were collected. Routine serologic techniques were used to test the serum samples for known SSc autoantibodies, and samples with negative results were further investigated by radiolabeled-protein immunoprecipitation assay.

Muscle Biopsy Findings in Combination With Myositis-Specific Autoantibodies Aid Prediction of Outcomes in Juvenile Dermatomyositis.

Objective: Juvenile dermatomyositis (DM) is a rare and severe autoimmune condition characterized by rash and proximal muscle weakness. While some patients respond to standard treatment, others do not. This study was carried out to investigate whether histopathologic findings and myositis-specific autoantibodies (MSAs) have prognostic significance in juvenile DM.

Systematic protein-protein interaction and pathway analyses in the idiopathic inflammatory myopathies.

Background: The idiopathic inflammatory myopathies (IIM) are autoimmune diseases characterised by acquired proximal muscle weakness, inflammatory cell infiltrates in muscle and myositis-specific/associated autoantibodies. It is unclear which pathways are involved in IIM, and the functional relationship between autoantibody targets has not been systematically explored. Protein-protein interaction and pathway analyses were conducted to identify pathways relevant to disease, using autoantibody targets and gene products of IIM-associated single nucleotide polymorphism (SNP) loci.

Anti-MDA5 autoantibodies in juvenile dermatomyositis identify a distinct clinical phenotype: a prospective cohort study.

Introduction: The aim of this study was to define the frequency and associated clinical phenotype of anti-MDA5 autoantibodies in a large UK based, predominantly Caucasian, cohort of patients with juvenile dermatomyositis (JDM).

Methods: Serum samples and clinical data were obtained from 285 patients with JDM recruited to the UK Juvenile Dermatomyositis Cohort and Biomarker Study. The presence of anti-MDA5 antibodies was determined by immunoprecipitation and confirmed by ELISA using recombinant MDA5 protein.

Calcinosis in juvenile dermatomyositis is influenced by both anti-NXP2 autoantibody status and age at disease onset.

Objective: Calcinosis is a major cause of morbidity in JDM and has previously been linked to anti-NXP2 autoantibodies, younger age at disease onset and more persistent disease activity. This study aimed to investigate the clinical associations of anti-NXP2 autoantibodies in patients with JDM stratified by age at disease onset.

Methods: A total of 285 patients with samples and clinical data were recruited via the UK Juvenile Dermatomyositis Cohort and Biomarker Study.

The diagnostic utility of autoantibodies in adult and juvenile myositis.

Purpose Of Review: The purpose of this study is to review recent advances in the diagnostic utility of autoantibodies in dermatomyositis.

Recent Findings: Alternative nonspecialist testing methods have been developed for anti-transcription intermediary factor 1 gamma, anti-MDA5 and anti-nuclear matrix protein 2, which are potentially exploitable by any hospital laboratory. Although these have yet to be validated for diagnostic use, it is likely that testing for myositis-specific antibodies will soon become readily available.

Novel autoantibodies and clinical phenotypes in adult and juvenile myositis.

Autoantibodies targeting intracellular proteins involved in key processes are detected in patients with idiopathic inflammatory myopathies. These myositis-specific autoantibodies have been increasingly demonstrated to correlate with distinct clinical phenotypes within the myositis spectrum. This review highlights the clinical associations of the myositis-specific autoantibodies, with particular attention to the recently identified and characterized novel myositis autoantibodies: p155/140, p140 (MJ), CADM-140 (MDA5), SAE, and 200/100.

Pathogenic mechanisms of disease in myositis: autoantigens as clues.

Purpose Of Review: There is increasing evidence of autoimmunity in dermatomyositis and polymyositis, with strong correlations between particular myositis-specific autoantibodies (MSAs) and clinical subsets. It is now clear that corresponding autoantigens are selectively targeted, have distinct adjuvant properties and are upregulated in target tissues, suggesting a role in disease pathogenesis. This review highlights recent findings including the identification of novel MSAs and studies investigating autoantigen properties and expression in both target tissues and tumours.

Myositis-specific autoantibodies: their clinical and pathogenic significance in disease expression.

The idiopathic inflammatory myopathies (IIMs)--DM and PM--have been historically defined by broad clinical and pathological criteria. These conditions affect both adults and children with clinical features including muscle weakness, skin disease, internal organ involvement and an association with cancer in adults. Using a clinico-serological approach, DM and PM can be defined into more homogeneous subsets.

Newly identified autoantibodies: relationship to idiopathic inflammatory myopathy subsets and pathogenesis.

Purpose Of Review: There is increasing evidence that patients with polymyositis and dermatomyositis have specific clinico-serological profiles. Myositis-specific autoantibodies target intracellular proteins involved in key processes such as translocation and nuclear transcription, and are closely linked to patterns of disease expression. This review highlights the recent work on novel myositis-specific autoantibodies, their autoantigen targets, the relationship to clinical subsets and potential role in pathogenesis.

Antigen binding to GM1 ganglioside results in delayed presentation: minimal effects of GM1 on presentation of antigens internalized via other pathways.

Plasma membrane rafts are sphingolipid- and cholesterol-rich patches that function as membrane trafficking and surface signalling regions. Ganglioside GM1 is an integral component of these microdomains, and Escherichia coli enterotoxin B subunit (EtxB) is a pentamer that binds with high affinity to GM1 resulting in GM1 cross-linking. We previously demonstrated that antigen coupled directly to EtxB resulted in enhanced presentation relative to antigen taken up by fluid-phase endocytosis.