Anti-OJ Ab

Laboratory assay overview

Anti-histidyl-tRNA synthetase autoantibodies are the most common Myositis Specific Antibodies (MSA), comprising 30-40% of Idiopathic Inflammatory Myopathies (IIM), although OJ specifically is seen in less than 5% of IIM. Anti-Synthetase antibodies can be found in polymyositis, dermatomyositis or overlap myositis. Symptoms associated with these antibodies include non-erosive arthritis, ILD, fever, mechanic's hands and Raynaud's.

Laboratory assay overview

This Anti-Synthetase Profile is comprised of Anti-Jo-1 Ab, Anti-PL-7 Ab, Anti-PL-12 Ab, Anti-EJ Ab and Anti-OJ Ab. Anti-synthetase syndrome is an autoimmune disease characterized by interstitial lung disease (ILD), non-erosive arthritis, myositis, Raynaud’s phenomenon, unexplained fever and/or mechanic’s hands.1

Laboratory assay overview

Interstitial Lung Disease (ILD) can complicate several collagen vascular diseases, including Systemic Sclerosis (SS),Sjorgens's Syndrome (SjS), Systemic Lupus Erythematosus (SLE), Rheumatoid Arthritis (RA), Idiopathic Inflammatory Myopathies (IIM), and ANCA-Associated Vasculitis (AAV). Identifying an underlying autoimmune disorder in ILD patients has critical importance in therapuetic decision-making and has a meaningful impact on prognosis.

Laboratory assay overview

A subset of interstitial lung disease (ILD) patients have underlying connective tissue diseases (CTDs). This panel serves as an aid for the diagnosis of CTDs, including rheumatoid arthritis, inflammatory myositis, systemic sclerosis, and Sjogren’s syndrome, that are associated with the development of ILD. If left untreated, these CTD patients may develop lung fibrosis and inflammation. ILD is a direct consequence of these pathological changes. When severe, ILD leads to restrictive lung disease, pulmonary arterial hypertension, and cardiac disease (cor pulmonale).

Laboratory assay overview

Interstitial Lung Disease (ILD) can complicate several collagen vascular diseases including Systemic Sclerosis, Idiopathic Inflammatory Myopathies, Sjogren's Syndrome, Systemic Lupus Erythematosis, Rheumatoid Arthritis, and ANCA-Associated Vasculitis. This profile is designed to identify an underlying autoimmune disorder, assist therapeutic decision-making and assess disease prognosis.

Laboratory assay overview

The MyoMarker 3 Plus Profile can be used to assist in the diagnosis of dermatomyositis, polymyositis and the anti-synthetase syndrome. Furthermore, it allows charcterization of various subsets of these disorders and offers prognostic information.

Laboratory assay overview

Myositis-specific autoantibodies (MSAs) are highly selective, usually exclusive and are associated with particular clinical phenotypes within the myositis spectrum. Myositis-specific autoantibodies to cytoplasmic enzymes that catalyze the binding of specific amino acids to their cognate tRNA define the anti-synthetase syndrome characterized by myositis and lung inflammation, and include autoantibodies to Jo-1 (antihistidyl-tRNA synthetase), PL-7 (threonyl), PL-12 (alanyl), EJ (glycyl), and OJ (isoleucyl). A further subset of myositis patients is characterized by the presence of autoantibodies directed against the signal recognition particle (SRP). Autoantibodies to Mi-2 (Mi-2/nucleosome remodeling and deacetylase (NuRD) complex) are detected in patients with hallmark dermatomyositis features. Autoantibody to a cytoplasmic 140-kDa protein, melanoma-differentiation associated gene 5 (MDA5), also known as anti-CADM140, identified patients with clinically amyopathic dermatomyositis (CADM) and rapidly progressive lung disease. Autoantibodies to transcriptional intermediary factor 1-gamma (TIF-1 y), a p155/140 nuclear protein involved in cellular differentiation, have been reported in adult and juvenile dermatomyositis; in adults, it is associated with malignancy. Autoantibodies to nuclear matrix protein NXP-2, another 140-kDa protein, is found in juvenile dermatomyositis (JDM). Anti-TIF-1 y and anti-NXP-2, two novel serological subsets in JDM, occur collectively in >40% of children and appear to identify those with more severe disease.

Quest Diagnostics population reference ranges

Quest Diagnostics calculates these statistical intervals for this specific assay and demographic group, not as universal optimal targets.