Type 1 diabetes (T1D) is a chronic autoimmune condition in which the body’s immune system attacks and destroys the insulin-producing cells in the pancreas, known as beta-cells (b-cells). This leads to a lack of insulin production, which is the underlying cause of the disease.
There are several types of autoantibodies that have been identified in individuals with T1D. These include:
- Glutamic acid decarboxylase autoantibodies (GADA)
- Insulinoma-associated-2 autoantibodies (IA2A)
- Islet cell autoantibodies (ICA), and
- Zinc transporter 8 autoantibodies (ZnT8A)
These autoantibodies can be detected through blood tests and they are often used as a diagnostic markers for T1D. Additionally, the presence of autoantibodies can also indicate an increased risk for the development of T1D, even before symptoms appear. Understanding the role of autoantibodies in T1D is crucial for the development of new therapies and prevention strategies for the disease.
Intact proinsulin is a precursor molecule of insulin. Intact proinsulin is produced by pancreatic b-cells and it is converted to insulin by the removal of C-peptide. Elevated levels of proinsulin relative to C-peptide (PI:C ratios) have been observed in individuals with T1D. This is thought to be due to a failure of the b-cells to correctly process proinsulin into insulin. Measuring proinsulin levels can provide insights into the disease etiology, help to identify individuals at high risk of developing T1D, and monitor their progression.