Islet Cell Antibodies Blood Test

Islet cell antibodies (ICA) are autoantibodies produced by the immune system that target the islet cells in the pancreas. The islets of Langerhans contain beta cells, which are responsible for producing insulin. In autoimmune type 1 diabetes, the immune system mistakenly attacks and destroys these beta cells, leading to insulin deficiency. Type 1 diabetes is an autoimmune condition where the body cannot produce sufficient insulin due to beta cell destruction. In contrast, type 2 diabetes is primarily characterised by insulin resistance—the body produces insulin but cannot use it effectively—and does not involve autoimmune processes. Islet cell antibodies are present in approximately 95% of people with autoimmune type 1 diabetes at the time of diagnosis, while they are typically absent in type 2 diabetes. This makes them valuable for distinguishing between the two types, which is important because treatment approaches differ significantly. The test may also help identify latent autoimmune diabetes in adults (LADA), sometimes called type 1.5 diabetes, which is a slowly progressing form of autoimmune diabetes that develops in adulthood and may initially be misdiagnosed as type 2 diabetes. Results are reported as positive or negative. A positive result indicates the presence of islet cell antibodies and suggests an autoimmune component to diabetes. However, results should always be interpreted alongside other clinical findings and diabetes markers by your healthcare provider.