Title: Developing and optimising pHLA multimas as a biomarker for T1D
Funder: Juvenile Diabetes Research Foundation

Abstract: HLA class I molecules present small parts of proteins, called peptides, at the cell surface where they can be examined by our immune systems The killer T-cells of the human immune system are designed to recognize HLA-bound peptides. Several lines of new evidence suggest that rogue killer T-cells might contribute to, and possibly cause, Type 1 diabetes by recognizing peptides on the surface of insulin-producing islet cells in the pancreas. Our objective is to develop new technologies to identify and characterize the killer T-cells that recognize these peptides and destroy insulin-producing cells. We have found that autoimmune killer T-cells are different to the much better studied anti-germ killer T-cells. These differences mean that current technologies for the study killer T-cells are very poor at identifying the killer T-cells that are associated with Type 1 diabetes (T1D). We have developed technologies that circumvent this problem. It is extremely important that we are able to locate and comprehensively analyze T1D-associated killer T-cells in patient samples. We can only study the role of these potentially important cells if we are able to find them. The work we propose will allow a comprehensive analysis of these cells and their potential role in disease for the first time. Killer T-cells of the human immune system are designed to recognize virus fragments bound by a self molecule called HLA class I. This clever system allows killer T-cells to find and eliminate cells that have been infected with germs The same mechanism is thought to be a key, but inadvertent part of the process that leads to Type 1 diabetes (T1D). In T1D, rogue killer T-cells are thought to kill insulin-producing cells in the pancreas. Recent advances resulting from JDRF-funded work in the UK have provided strong support for this assertion, by showing that people with certain HLA class I molecules have a higher genetic risk of developing T1D and by generating killer T-cell clones from patients that can kill insulin-producing beta cells. We have built on these foundations with our recent JDRF award by showing there are high levels of killer T-cells that recognise a fragment of the preproinsulin molecule in T1D patients. We have also used X-rays to visualize the precise molecular interactions that enable this activity. Here we aim to build enhanced molecular reagents that bind to and identify those T-cells with the capacity to kill insulin-producing cells enabling us to track, study and understand these rogue cells. We have secured $100,000 of materials from the fastest growing commercial player in such T-cell detection technologies during infection. We are now in a unique position to pioneer such exciting approaches in autoimmune situations using T1D as a model system. Successful reagents will be made available to the T1D research community via Immudex (Copenhagen). These studies address a critical research gap by using novel approaches to solve the problem of detecting T1D-associated killer T-cells. In turn, our findings are expected to translate to a better understanding of how killer T-cells contribute to T1D. It is possible that the presence of activated T1D-associated killer T-cells in patient blood may act as an early biomarker of disease. The building of robust reagents for detecting these cells as we propose may enable early detection and treatment of disease before the onset of symptoms The technologies developed in these studies will allow the tracking and study of Type I diabetes (T1D)-associated killer T-cells in patient samples for the first time. Our recent studies have demonstrated that killer T-cells isolated from T1D patient blood can kill insulin-producing beta cells in the laboratory. Other studies this year have placed such killer T-cells firmly at ‘the scene of the crime’ early in disease. The existence of beta-cell-specific killer T-cells in the blood with an activated profile may provide an easily accessible marker of what coul


Research activity codes: 4.1 DISCOVERY AND PRECLINICAL TESTING OF MARKERS AND TECHNOLOGIES
Health categories: METABOLIC AND ENDOCRINE