Abstract
Gut is always exposed to enteric bacteria and food antigens, but maintains its homeostasis without the development of acute or chronic inflammation in normal situations. In contrast, abnormal innate immunity to enteric flora may develop intestinal inflammation in inflammatory bowel disease (IBD). This paper reviewed recent studies regarding intestinal macrophage (Mφ) function in gut. Intestinal Mφ contributes to the elimination of pathogens and gut immune homeostasis. However, it also causes chronic inflammation by producing proinflammatory cytokines. Thus, intestinal Mφ is “a double-edged sword” for individuals. Dysregulation of this mucosal immune system may induce abnormal responses to commensal and food antigen resulting in development of IBD.
