The immune system is possibly the most complex system in the human body. This intricate array of interconnected cells and signals provides a sophisticated defence mechanism against potentially harmful materials, both living and non-living. Functions of the immune system include recognizing foreign substances, neutralization and expulsion from the body. This incredible system provides a life-saving function on a daily basis by protecting us against opportunistic infections and diseases, and the system is not easily duped into tolerating anything that is “non-self”.
While the immune system’s trigger-happy sensitivity is a virtue for protecting against truly harmful invading substances, it can also lead to problems. For example, diseases like type 1 diabetes (T1D), Crohn’s disease and rheumatoid arthritis are examples of an overzealous immune system attacking the host’s own tissues by failing to differentiate self from non-self. In the case of T1D, the pancreatic islet cells are attacked and destroyed, leading to the inability of the host to produce insulin. Another challenge is presented when there is a desire to introduce something foreign into the body, such as the case with transplantation surgeries. The Edmonton Protocol, the pancreatic islet cell transplant procedure developed by ADI scientists and adopted around the world, is one such example. This procedure is potentially life-saving for recipients, but must overcome rejection by the recipient’s own immune system. While donor-recipient matching alleviates some of this rejection, there is still a need to further suppress the immune system with drugs to achieve sufficient tolerance. The Edmonton Protocol represents the most advanced approach to date for islet transplantation combined with immunomodulation, but there are still challenges posed by inherent recipient rejection and the toxicity of immunosuppressive drugs.
Immunology research at the ADI focuses on two key areas that are intimately linked: striving to better understand the aspects that make up and control the immune system, and using this knowledge to develop immune response modulation. Understanding the immune system is like peeling an onion – immunity has multiple layers of defence that are not easily overcome with a single strategy. But scientists at ADI are steadily making progress towards unravelling these mechanisms. More importantly, they are using this knowledge to improve on the immunosuppression procedure they developed for the Edmonton Protocol. While one goal of immunology research is to develop improved drug therapies that produce minimal side effects in the patient, the ultimate goal is to achieve islet transplantation that elicits zero immunogenicity, alleviating the need for any immunosuppression.