Friend or Foe? Scientists Determine How the Intestine Keeps Us Safe From Microbial Invaders

How the immune system is switched on and off, or how it detects friend or foe, has baffled scientists for years. New research from the University of Pennsylvania School of Veterinary Medicine shows that tiny cells called intestinal epithelial cells play a central role in both turning on anti-microbial immune responses and turning off harmful responses that can cause chronic inflammation in the intestine.