Type 1 Diabetes Can be Identified Early by a Blood Test
Being able to predict patients who will develop Type-1 diabetes is of great clinical importance. Using technology developed by Antigen Express, a wholly-owned subsidiary of Generex Biotechnology, Antigen Express researchers are now a step closer to a reliable, highly sensitive blood test that will identify Type-1 diabetes patients to allow early intervention.
This new research will be presented at the American Diabetes Association’s 68th meeting, June 6-10, in San Francisco.
Type-1 diabetes occurs when the immune system mistakenly attacks pancreatic beta cells(the insulin producing cells). A key factor in the development of Type-1 diabetes is T cell mistaken recognition of islet cell antigens.
Several proteins are associated with development of Type-1 diabetes, in particular insulin and glutamic acid decarboxylase 65 (GAD65). (Currently, a highly sensitive, specific assay for T cells reactive to insulin or GAD65 is still under development, and not available as a diagnostic or prognostic tool to clinicians.) At the present time, Type I diabetes can only be diagnosed by the presence of antibodies when the disease is already well underway.
The antigen used in the new study was called GAD65, a protein that frequently triggers the autoimmune response in some type 1diabetics. Scientists attached an antigenic peptide derived from GAD65 to a protein fragment, which is associated with mistaken activation (an autoimmune response) of receptors on the T cells.
Investigators isolated peripheral T cells from thirteen patients with Type-1 diabetes, and 17 healthy subjects matched for age. T cells were then analyzed for T cell activation. T cells from patients with Type I diabetes demonstrated a distinct profile of activation compared to cells from healthy volunteers.
T cell reactivity to GAD65 is of particular interest in individuals who develop diabetes later in life, as this helps to differentiate them from the more common Type-2 diabetes. Since treatment and maintenance differ considerably for the two diseases, a validated diagnostic based on GAD65 could put those patients on the right treatment regimen earlier. A test based on might also be useful in monitoring treatments of clinical-stage diabetes medications.
It could also help identify patients at high risk for developing Type-1 diabetes later in life, or who are at the disease’s earliest stages. Several studies are underway that attempt to delay or reverse the onset of Type-1 diabetes by slowing down or even turning off the autoimmune response against insulin and islet cell antigens.
