Anti‑insulin receptor antibodies (IRAb) are autoantibodies that target the insulin receptor, a key transmembrane protein responsible for mediating insulin’s metabolic effects. By binding to the receptor’s extracellular domain, these antibodies can either block insulin signaling—leading to severe insulin resistance—or, less commonly,
activate the receptor and cause hypoglycemia 1. IRAb is most often associated with a rare autoimmune condition known as type B insulin resistance syndrome, which is frequently linked to underlying disorders such as systemic lupus erythematosus or other autoimmune diseases 2. Their presence disrupts normal glucose homeostasis, resulting in extreme metabolic instability that can be difficult to manage clinically. Understanding the structure, binding characteristics, and physiological impact of IRAb is essential for
diagnosing autoimmune insulin resistance and guiding targeted therapies, including immunosuppression and metabolic management strategies.

This assay is a sandwich enzyme-linked immunosorbent assay (ELISA). The microtiter plate is pre-coated with a human insulin receptor protein. Controls and samples are pipetted into the wells and any human IRAb present is bound by the immobilized protein. After washing away any unbound substances, a biotin labelled human insulin receptor protein is added to the wells. After wash step to remove any unbound reagents, streptavidin-horseradish peroxidase conjugate (STP-HRP) is added. After the last wash step, an HRP substrate solution is added and color develops in proportion to the amount of human IRAb bound initially. The assay is stopped, and the optical density of the wells is determined using a microplate reader. The increases in absorbance are directly proportional to the amount of captured insulin receptor autoantibody.

The following assay data is provided for demonstration only. A dataset should be generated for each set of sample assay.

Precision
Intra-assay Precision (Precision within an assay) C.V. <8%.
Inter-assay Precision (Precision between assays) C.V. <10%.