Graves’ Disease

Graves’ disease (GD) is a prevalent autoimmune thyroid disorder and the leading cause of hyperthyroidism, affecting up to 1% of the population. It stands as one of the most common autoimmune diseases globally. It arises when the immune system produces thyroid-stimulating hormone receptor antibodies (TRAb), which bind to and activate the thyroid-stimulating hormone receptor (TSHR). This abnormal stimulation causes excessive thyroid hormone production, leading to characteristic symptoms such as unintended weight loss, tachycardia, heat intolerance, and tremors. Some patients also develop Graves’ orbitopathy, characterized by bulging eyes, discomfort, and vision problems [1, 2, 3].

The detection of TRAb is pivotal for diagnosing GD, distinguishing it from other thyroid disorders, and monitoring treatment efficacy. As a hallmark of GD, TRAb has become an indispensable biomarker. Over the years, advances in diagnostic technology have dramatically enhanced the sensitivity and specificity of TRAb detection, ensuring more accurate and efficient diagnoses [1]

Advanced Diagnostics with third-generation Immunoassay 

Diagnostic assays for TRAb detection have evolved through three generations, each offering improvements in performance and practicality: 

• • • 1st generation assays utilized TRAb’s ability to inhibit the binding of labeled TSH to TSHR in the fluid phase. While foundational, their sensitivity was limited. 
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  • • 2nd generation assays employed immobilized TSHR on solid phases, significantly improving sensitivity without compromising specificity. 
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  • • 3rd generation assays  encompass the use of solid phase-immobilized TSHR and a monoclonal TRAb recognizing the TSH binding site replacing TSH as the competitive reagen.

At Medipan & GA Generic Assays we have developed 3rd generation radioimmunoassays (RIA) and enzyme-linked immunosorbent assays (ELISA) advancing TRAb detection methodologies. Solid phase-immobilized human TSHR and the mouse monoclonal TRAb mimicking the binding of TSH to the TSHR are used for the competitive assay environment.  

The SELco^® TRAb human 1 step represents an innovative radioimmunoassays (RIA) in diagnostic innovation. This combines typically elevated precision and superior sensitivity of RIA with efficiency to meet the challenges of TRAb detection. Utilizing a competitive reaction mechanism in a single-step protocol, it reduces processing time while maintaining unparalleled diagnostic accuracy. Its design is tailored for automation, making it particularly suited for routine use in nuclear medicine laboratories [2]. 

The Medizym^® T.R.A. human offers a highly sensitive and specific ELISA-based method for detecting TSH receptor autoantibodies for all laboratories. Optimized for manual processing as well as automation with widely used ELISA processors, this test ensures efficiency and consistency in high-throughput laboratories. Its standardization capabilities make it a robust tool for routine diagnostics, meeting the demands of both large-scale and specialized clinical settings [3]. 

These advancements not only improve diagnostic accuracy but also streamline workflows, paving the way for more efficient management of GD in both routine and specialized clinical laboratories. 

References 

[1] Zöphel, Z., et al. (2010). “Continuously Increasing Sensitivity over Three Generations of TSH Receptor Autoantibody Assays” Horm Metab Res, 42: 900–902

[2] Roggenbuck, J. J., et al. (2021). “Third generation radioimmunoassay (RIA) for TSH receptor autoantibodies (TRAb) – one step less, similar results?” Nuklearmedizin, 60(1), 38-46

[3] Roggenbuck, J. J., et al. (2019). “A novel third-generation TSH receptor antibody (TRAb) enzyme-linked immunosorbent assay based on a murine monoclonal TSH receptor-binding antibody.” Immunologic Research, 66(5), 768-776