Modulation of gastrointestinal inflammation by chimeric proteins in experimental models

Conventional drug therapy in patients with chronic gastrointestinal inflammation is clinically effective in the majority of patients. However, in a relevant group of patients with highly active disease refractory to conventional drugs and for patients with severe side effects new therapeutic strategies are necessary. An advanced understanding of the immune mechanisms underlying chronic diseases resulted in the possibility to use chimeric proteins, in which the variable domains of an immunoglobulin are replaced by extracellular domains of cell surface molecules or cytokines for specific immunomodulation. The immunomodulating effects of chimeric proteins such as CTLA-4-IgG, interleukin-10-IgG, IL-2-IgG or tumour necrosis factor (TNF)-receptor IgG have been proven beneficial in a variety of in vitro and in vivo models of chronic gastrointestinal inflammation and autoimmune diseases. It thus seems likely that genetically engineered fusion proteins targeting specific elements of the immune response may become an essential element in new clinical treatment protocols.