Ulcerative colitis is a chronic inflammatory disease of the large intestine usually characterized by acute episodes with recurring bouts of diarrhea, intestinal bleeding and colic. It is estimated that more than 150,000 people in Germany are affected by this disease, which is caused by a misdirected immune reaction in which the immune system mistakenly attacks cells in the large intestine. As the disease can be very different from one person to the next—both in its characteristics and also presumably in its causes—the few drugs that have been approved to date are largely only effective for some and nowhere near all of those affected. Therefore there is a large unmet need for therapies to fight IBD via new mechanisms of action. These could supplement the existing range of therapies with a new active principle and would therefore also have the potential to help patients for whom existing therapies have so far remained unsuccessful.