In addition to their well-known role in acute injury and chronic
inflammation, “innate” cytokines play an important role in health
and the maintenance of normal immune homeostasis. This group includes
the prototypic cytokines IL-1 and TNF alpha, as well as several other
members belonging to the IL-1 and TNF family, such as IL-18, IL-33,
IL-36-38, and TL1A. The dichotomous role of these cytokines has been
best characterized in the intestine where innate cytokines may play both
a protective and a pro-inflammatory role, depending upon the
immmunological status of the host or the type and phase of the
inflammatory process. This new information has produced novel
pathogenetic hypotheses that have important translational implications
both in regard to the prevention and treatment of chronic intestinal
inflammation, including Crohn’s disease and ulcerative colitis, the two
major forms of inflammatory bowel disease. This review will discuss and
summarize current data regarding the role of IL-1, TNF alpha, and their
family members in regulating gut mucosal homeostasis and chronic
intestinal inflammation. (C) 2012 Published by Elsevier Ltd