Animal models of inflammatory bowel disease: how to make the right choice?

Ulcerative colitis (UC) and Crohn’s disease (CD) belong to the group of inflammatory bowel diseases (IBD), being chronic relapsing inflammatory conditions of the gastrointestinal tract. There is a continuous increase in morbidity and disability among the working-age young population aged 20-40 years. The most effective method for studying the pathogenesis of the disease and developing new lines of therapy remains experimental modelling of IBD in vivo. There are more than sixty different experimental models of UC and BC in animals, which include chemically induced colitis (oxazolone, TNBS, sodium dextran sulfate, acetic acid), models with adaptive T-cell transfer, genetic models, models with spontaneous mutations, and models induced by changes in the composition of the intestinal microbiota. Despite the results obtained in animal studies and which have made a huge contribution to the study of the mechanisms of IBD, today there is no ideal model that would ensure full compliance with the clinical situation. When choosing an experimental model, a number of factors should be taken into account, namely, the localization of inflammation, the nature of the inflammatory stimulus, the dynamics of the course of inflammation, the features of the immune response and the composition of the cellular infiltrate, as well as the presence of chronic complications specific to the two most important forms of IBD.