Anti-Nuclear antibodies: Current concepts and future direction for diagnosing connective tissue disease

Abstract

Identification of antinuclear antibodies has been used for the diagnosis of connective tissue diseases for more than fifty years. Indirect immunofluorescence on human epithelial (HEp-2) cells is considered the gold standard screening method for the detection of antinuclear autoantibodies. As the demand of ANA testing increased, the need for automation and standardization has also come forth. A high level of false positive and false negative cases is seen in various populations making it difficult to take clinical decisions. Newer technologies were introduced for the antibody detection to ensure high sensitivity and specificity. This article intends to provide an overview of the concepts on ANA testing, the different diagnostic methods available, the various patterns and clinical utility, the clinical guidelines to be followed, the drawbacks and what lies ahead in the future of ANA testing.

A Hospital-Based Insight into the Antinuclear Antibody Patterns in Autoimmune Disorders

“…2 The ANA attack self-proteins within cell nucleus structures, now encompassing nuclear envelope components, mitotic spindle apparatus, cytosol, cytoplasmic organelles, and cell membranes. 3 Their presence in serum may indicate either a systemic autoimmune disease like systemic lupus erythematosus (SLE), scleroderma and polymyositis/dermatomyositis, or an organ-specific condition like autoimmune thyroiditis and hepatitis. 2 Identification of ANA patterns and their target antigen on the basis of variable cellular staining pattern can be correlated to specific autoimmune disease as part of diagnostic clinical immunology.…”

Autoantibodies in healthy blood donors, rheumatic and autoimmune liver diseases

“…One of the well-known and most frequently requested autoantibody tests is autoantibodies against nuclear antigens, i.e., antinuclear antibodies (ANA). ANA constitute a large family of autoantibodies with multiple specificities that are associated with many rheumatologic disorders but can also be found in, e.g., autoimmune liver diseases (8). In addition to ANA, an increasing number of autoantibody specificities against several tissue-and cell-associated antigens have been identified and many of these are associated with specific muscular, renal and neurologic autoimmune diseases (9).…”