Anti-GAD (Glutamic Acid Decarboxylase) antibodies, often referred to as GAD autoantibodies or GADA, target the enzyme glutamic acid decarboxylase, which catalyzes the conversion of glutamate to γ-aminobutyric acid (GABA). Two main isoforms of GAD exist—GAD65 and GAD67—with GAD65 being the primary target in autoimmune diabetes. GAD65 is expressed in pancreatic β-cells and neurons, and its autoimmune recognition marks a key step in the immune-mediated destruction of β-cells that leads to type 1 diabetes mellitus (T1DM). Anti-GAD antibodies are among the earliest and most persistent islet autoantibodies detected during the preclinical phase of T1DM, often years before disease onset.
In the clinical context, anti-GAD antibody testing is widely used for the diagnosis and differentiation of autoimmune diabetes. It helps confirm type 1 diabetes and is particularly valuable in identifying latent autoimmune diabetes in adults (LADA) —a slowly progressive form of autoimmune diabetes that can initially resemble type 2 diabetes. The presence of anti-GAD antibodies indicates ongoing autoimmune activity against pancreatic β-cells and can guide management decisions, such as the likelihood of insulin dependence. Elevated anti-GAD levels may also appear in certain neurological autoimmune conditions, including stiff-person syndrome, cerebellar ataxia, and autoimmune encephalitis, reflecting the enzyme’s neuronal expression.
In research settings, anti-GAD antibodies are central to studies on autoimmune pathogenesis, disease prediction, and immune tolerance mechanisms. They are commonly used as biomarkers in prospective cohort studies of individuals at genetic risk for T1DM and as endpoints in immunotherapy trials aimed at halting or delaying β-cell destruction. Investigating GAD autoimmunity has also provided insights into cross-reactivity between the endocrine and nervous systems, supporting its dual relevance in diabetes and neuroimmunology research.
This product is manufactured in Germany by Medipan GmbH.
| Size | 1 x 96 Well |
| Incubation Time | 2 hours 40 minutes |
| Sample Type | Serum |
| Storage | 2-8°C |
| Alternative Names | Anti-GAD antibodies, GAD autoantibodies, glutamic acid decarboxylase antibodies, GADA, and anti–glutamate decarboxylase antibodies |
