Inflammation in IBD
Inflammation in IBD and function of TNFα
The pathogenesis of inflammatory bowel disease begins with injury to the gastrointestinal mucosa, diminishing the integrity of this barrier. Then, either chronic or repetitive assault from gastrointestinal bacteria or antigens leads to stimulation of inflammatory processes. Activation of antigen-presenting cells
promotes the differentiation of helper T cells, which enter a self-sustaining cycle with macrophages when combined with key cytokines (IFN = interferon). The activated macrophage then secretes TNFα.
TNFα plays a major role in the inflammation process. It acts at 4 levels:
In the self-sustaining inflammatory cycle, macrophages produce all of the following EXCEPT:
Extra info: To a great extent, the cyclic nature of the inflammatory process is due to macrophageal generation of IL-12 and IL-18, which stimulates macrophage reponse.