Intestinal subepithelial myofibroblasts and mucosal immunophysiology

Abstract
A major challenge in gastrointestinal immunophysiology is to define the mucosal cells and soluble mediators whose integrated actions modulate gut absorption, secretion, motility, and blood flow. This knowledge has immense significance not only for attaining an in-depth understanding of normal physiology, but also for evolving insight into the molecular etiology and pathogenesis of gastrointestinal inflammatory disease. This article summarizes current knowledge of specialized mucosal cells commonly referred to as pericryptal fibroblasts or subepithelial myofibroblasts. Subepithelial myofibroblasts are members of a family of phenotypically interrelated cells that we collectively call juxtaparenchymal cells. Recognized morphologically for more than 25 years, the role of juxtaparenchymal cells in mucosal function remains an enigma. Given their strategic location at the interface between the epithelium and lamina propria, juxtaparenchymal cells may modulate information transfer between these tissue compartments and play a pivotal role in mucosal immunophysiology.