Intestinal Fibroblasts (IF)

Fibroblasts are mesenchymal cells derived from the embryonic mesoderm. They have been extensively used for a wide range of cellular and molecular studies, as they are one of the easiest types of cells to grow in culture. In addition, their durability makes them amenable to a wide variety of manipulations ranging from studies employing gene transfection to microinjection. There is evidence showing that fibroblasts in various organs are intrinsically different. Fibroblasts secrete a non-rigid extracellular matrix that is rich in type I and/or type III collagen. Intestinal fibroblasts (IF) constitutively express both IL21R and the common gamma chain receptor, which are necessary for IL21-driven signalling. IL21 enhances intestinal fibroblast production of MMP-1,2,3 and 9, but not tissue inhibitors of MMP-1 and 2. IBD LPMC supernatants stimulate MMP secretion by intestinal fibroblasts, and this effect is partly inhibited by IL21R/Fc. These results suggest that intestinal  fibroblasts are a potential target of IL21 in the gut and that IL21 controls MMP secretion by fibroblasts.