AutoImmun: Novel tests for T1DM diagnostics

In the joint project AutoImmun, the Kompetenzzentrum Diabetes Karlsburg (KDK) in cooperation with the company EUROIMMUN is developing a new test system for the diagnosis of diabetes mellitus type 1. The aim of the project is to realize a rapid and easy-to-use test that detects diabetes-associated autoantibodies against glutamate decarboxylase (GAD65), tyrosine phosphatase (IA-2) and insulin already at an early stage. AutoImmun is thus developing a functional alternative to previously used methods.

In this regard, the project team is using a chemiluminescence immunoassay. Chemiluminescence immunoassay is a method for detecting even the smallest traces of antibodies in an organism. It is based on the chemical reaction of an antigen with an antibody. In this phenomenon, part of the energy released is emitted in the form of visible light, which is then measured. To date, the radioimmunoassay is considered the gold standard in the diagnosis of type 1 diabetes mellitus. However, due to the use of radioactively labeled antigens, the procedure is relatively time-consuming and requires a corresponding amount of safety and technical effort.  

Furthermore, the AutoImmun collaborative project aims to explore alternatives for the diagnosis of type 1 diabetes autoantibodies. A possible alternative to the detection of autoantibodies could be the direct detection of the diabetes-associated autoantigens glutamate decarboxylase (GAD65) and tyrosine phosphatase (IA-2) in the body, since the formation of autoantibodies requires the release of autoantigens from damaged beta cells. Initial studies on the detection of GAD65 antigens showed the feasibility of this approach in principle. The detection of autoantigens would not only be of interest for the prediction and differential diagnosis of diabetes, but also of relevance for the early detection of graft rejection in patients after islet cell transplantation.

At the Kompetenzzentrum Diabetes Karlsburg , the chemiluminescence immunoassay test systems developed in the project will be tested for their sensitivity and specificity. In close cooperation with the Klinikum Karlsburg, the development and validation of the special bioanalytical method will then be carried out with clinically characterized patient samples.

In parallel, medical aspects will be investigated. Of interest here is whether the measurement of autoantibodies is also suitable for monitoring the course of the disease in patients with type 1 diabetes and whether they could provide indications of incipient late complications. For this subproject, clinical course samples of newly manifested type 1 diabetes patients will be collected over a period of 2 years and the correlation of marker levels with disease and therapy progression will be investigated.

The detection of single autoantibodies is the earliest sign of the autoimmune process. The risk of developing type 1 diabetes mellitus increases with the concentration, number, and specificity of different autoantibodies. The chances of successful therapeutic intervention are greatest at the time of single autoantibody detection. By using automatable, sensitive autoantibody screening, type 1 diabetes diseases can be detected and treated at an early stage in the future.