Key Interleukins in Inflammatory Bowel Disease-A Review of Recent Studies

Inflammatory bowel disease (IBD) is an immune disorder of the gastrointestinal tract with a complex aetiopathogenesis, whose development is influenced by many factors. The prevalence of IBD is increasing worldwide, in both industrialized and developing countries, making IBD a global health problem that seriously affects quality of life. In 2019, there were approximately 4.9 million cases of IBD worldwide. Such a large number of patients entails significant healthcare costs. In the treatment of patients with IBD, the current therapeutic target is mucosal healing, as intestinal inflammation often persists despite resolution of abdominal symptoms. Treatment strategies include amino salicylates, corticosteroids, immunosuppressants, and biologic therapies that focus on reducing intestinal mucosal inflammation, inducing and prolonging disease remission, and treating complications. The American College of Gastroenterology (ACG) guidelines also indicate that nutritional therapies may be considered in addition to other therapies. However, current therapeutic approaches are not fully effective and are associated with various limitations, such as drug resistance, variable efficacy, and side effects. As the chronic inflammation that accompanies IBD is characterized by infiltration of a variety of immune cells and increased expression of a number of pro-inflammatory cytokines, including IL-6, TNF-α, IL-12, IL-23 and IFN-γ, new therapeutic approaches are mainly targeting immune pathways. Interleukins are one of the molecular targets in IBD therapy. Interleukins and related cytokines serve as a means of communication for innate and adaptive immune cells, as well as nonimmune cells and tissues. These cytokines play an important role in the pathogenesis and course of IBD, making them promising targets for current and future therapies. In our work, we review scientific studies published between January 2022 and November 2024 describing the most important interleukins involved in the pathogenesis of IBD. Some of the papers present new data on the precise role that individual interleukins play in IBD. New clinical data have also been provided, particularly on blocking interleukin 23 and interleukin 1beta. In addition, several new approaches to the use of different interleukins in the treatment of IBD have been described in recent years.