3507 – Medizym^® anti-GAD M

Highlights

• Use of recombinant human glutamic acid decarboxylase (GAD65)
• Quality assured handling in routine laboratories
• Incubation at room temperature
• Quantitative determination of antibodies against GAD65)
• Calibrated with the international standard preparation NIBSC code 97/550
• Results expressed in IU/mL
• Excellent diagnostic sensitivity and specificity
• High precision within the measurement range
• Performance characteristics are provided in the current Instructions for Use (IFU)
• CE marked
• Fully automatable

Intended Purpose

The Medizym^® anti-GAD M is a quantitative enzyme-linked immunosorbent assay for the determination of antibodies against Glutamic Acid Decarboxylase (GAD₆₅) in human serum. The Medizym^® anti-GAD M is intended as an aid in the diagnosis of diabetes mellitus type 1 , when used in conjunction with other clinical and laboratory finding. The immunoassay is designed for manual professional in vitro diagnostic use.

Diagnostic Relevance

Type 1 Diabetes Mellitus: Overview

Type 1 diabetes mellitus is a chronic autoimmune disease in which the immune system destroys the insulin-producing beta cells of the pancreatic islets of Langerhans. As a result, insulin production decreases, which leads to elevated blood glucose levels characteristic of diabetes mellitus. Although genetic predispositions and viral infections are considered important risk factors, the exact causes remain incompletely understood.

Role of Islet Cell Antibodies

Islet autoantibodies are important biomarkers of autoimmune beta-cell injury and may be detected months to years before the clinical onset of type 1 diabetes. Beta-cell destruction is driven predominantly by T-cell-mediated immune mechanisms rather than by autoantibodies themselves.

Autoantibodies against GAD65, IA-2, ZnT8, insulin, and islet cell antigens (ICA) are valuable markers for identifying autoimmune diabetes and assessing the risk of disease development. Their combined determination supports the laboratory diagnosis of type 1 diabetes when interpreted together with clinical findings and other laboratory results.

Biochemical Perspective: Glutamic Acid Decarboxylase (GAD)

Glutamic acid decarboxylase (GAD) catalyzes the synthesis of the neurotransmitter GABA in the brain and in pancreatic beta cells. Two isoforms exist: GAD65 (65 kDa) and GAD67 (67 kDa). Most patients with type 1 diabetes, as well as many prediabetic individuals, develop antibodies against GAD65.

In contrast, patients with the rare neuromuscular Stiff-man syndrome produce antibodies against both GAD isoforms.