T cell transfer model of colitis: a great tool to assess the contribution of T cells in chronic intestinal inflammation.

Inflammatory bowel diseases (IBD) consist of Crohn's disease (CD) and ulcerative colitis (UC) affecting about 0.1% of the western population. These two chronic gut diseases affect youth at their prime of life causing diarrhoea, intestinal bleeding, and severe gut discomfort. Mouse models of colitis have been major tools in understanding the pathogenesis of IBD. A number of mouse models are available to assess the contribution of T cells in the pathogenesis of CD and UC. Among these, the T cell transfer model of colitis is the most widely used model to dissect the initiation, induction, and regulation of immunopathology in chronic colitis mediated by T cells. The methodology below describes the classification of various animal models and explains the T cell transfer model in detail, including flow cytometry-based isolation of naïve T cells that are used in the transfer, immunological concepts, detailed immune-pathological assessment, shortcomings of the model, and the latest improvements to this colitis model. A special focus is paid to the utilisation of the T cell transfer model in delineating the immunopathology in a primary epithelial defect model of colitis, namely Winnie.