Generating and Analyzing Germ-Free Mice.

The normal gut microbiota has evoked many investigators' interest over the years and the pioneering work of James Reyniers in the 1920s generated the first germ-free guinea pigs. Comparing the physiology between germ-free and conventionally raised animals has provided invaluable insights on how the gut microbiota affect host biology. Today we know that the gut microbiota modulate the immune system, epithelial cell proliferation, intestinal angiogenesis, hormone production, energy absorption, and behavior. Furthermore, recent data have demonstrated that obesity is associated with an altered gut microbiota, and a direct role for the microbiota in disease development was demonstrated by the use of germ-free mice. Here we are presenting protocols for maintaining and generating germ-free mice. Curr. Protoc. Mouse Biol. 2:307-316 © 2012 by John Wiley & Sons, Inc.