Detection of Diagnostic Antibodies in Immune-Mediated Diseases: A Focus on Antigens and Technologies

Autoimmune diseases are conditions characterized by aberrant B-cell and T-cell reactivity against self-antigens. Autoantibodies are serological biomarkers of autoimmune diseases, as such, autoantibody testing is a key step for diagnosing and classifying many autoimmune diseases, as well as monitoring disease activity and devising a treatment strategy. Considering the rising number of people affected by autoimmune diseases worldwide, it is even more important to have efficient techniques that combine high sensitivity and specificity with reduced sample processing times and an automated high-throughput workflow. In this context, the identification and validation of new autoantigens and autoantibodies, together with the implementation of technological advancements, has led, in the last decades, to an improvement in patient diagnosis and stratification. Here, we review the major antigens of some of the most common autoimmune diseases, and the most widely used assays employed in diagnostic laboratories for the detection of their cognate antibody, confronting more traditional platforms with emerging ones in selected cases of study.