Experimental Immunology

No matter where we are, we are surrounded by pathogens – bacteria, viruses, fungi and parasites are everywhere. The human immune system has developed various strategies to control the spreading of pathogens within the body and to prevent their pathogenic effect to keep us healthy. On a random basis, our body produces highly specific immune cells (T and B lymphocytes) to specifically recognize and attack the numerous pathogens. Certainly, this random process bears the risk that cells are generated that recognize molecules of the own body instead of pathogens and thereby might cause autoimmune diseases like rheumatoid arthritis, diabetes or multiple sclerosis.

Regulatory T cells, the "Blue Helmets" of the immune system

The vast majority of those self-reactive immune cells are already eliminated during the process of their generation by a control procedure called "central tolerance". However, a number of self-reactive cells escapes the elimination and exists in any human. In order to prevent an attack on the body's own cells and thus the generation of autoimmune diseases, the immune system has developed various regulatory mechanisms, so-called "peripheral tolerance mechanisms".

As an important part of the peripheral tolerance regulatory T cells (Tregs) are produced, which belong to the group of T lymphocytes. One can imagine these cells as “blue helmets” of the immune system. Their function is to prevent immune reactions against the body's own tissues. Additionally, Tregs interfere in a de-escalating way within the body's defense against invading pathogens and prevent excessive immune reactions, which in worst case can cause severe organ damage. However, if Tregs are present at too high numbers, wanted immune responses against pathogens and tumors as well as responses towards vaccinations might be suppressed. Thus, an optimal balance of Tregs is essential for a fully functional immune system.

In order to apply or modulate Tregs for therapeutic purposes, we have to extend our knowledge about their origin, functional properties and mechanisms of action. This is the focus of the Department of Experimental Immunology.