Interleukin 6: biological significance and role in inflammatory bowel diseases

Cytokines affect a number of processes in the living body. Interleukin 6 (IL-6) is a cytokine involved in inflammation, infection response and also regulation of metabolism. It stimulates target cells through a membrane-bound IL-6 receptor. Inflammatory bowel diseases (IBD) are autoimmune diseases whose incidence and prevalence are increasing worldwide. It is a group of chronic gastrointestinal disorders characterized by multifactorial, still unknown pathogenesis, varied symptomatology, course with periods of exacerbation and remission, and polymorphic infiltration in histopathological examination. As it is known, pro-inflammatory cytokines, including IL-6, in IBD initiate, intensify and support the development of the inflammatory process in the intestine. Our knowledge of IL-6 biology has important consequences for therapeutic strategies. Elevation of IL-6 concentration can be considered as an early and sensitive, although non-specific marker for various inflammatory conditions and may be used in the diagnosis and monitoring of patients with IBD.