The Immunological Importance of the Mesentery

Abstract

The mesentery contains large amounts of adipocytes and is actively involved in the storage of lipids as well as the release of various adipokines controlling immune cell homeostasis and metabolism. Ileal Crohn’s disease, a subform of inflammatory bowel disease, is characterized by the development of creeping fat where the inflamed intestinal ileum is tightly wrapped with hyperplastic mesenteric adipose tissue, ultimately leading to the recruitment of various lymphocytes and monocytic cells and the secretion of adipokines and cytokines. The functional role of this phenomenon has been the topic of numerous studies over the last decades. In this book chapter, we will focus on the immune modulatory role of creeping fat and thus the position within Crohn’s disease itself and discuss the immune regulatory function of key adipokines as well as of distinct immune cell populations identified within creeping fat. Furthermore, we will provide a working model based on the currently available literature. Although the characteristic changes of mesenteric fat in Crohn’s disease have been described for a long time, the discussion of cause and consequence of this finding is still ongoing. In this chapter, we will focus on the immune regulatory role of the mesentery in Crohn’s disease and conclude by suggesting a working model, thus summarizing the current knowledge.