摘要
As the interface between the gut lumen and the body,the intestinal epithelial layer is continuously exposed to large numbers of microbial and dietary antigens.Consequently,intestinal homeostasis requires sophisticated immune networks that effectively clear pathogenic microbes while maintaining tolerance to harmless antigens.To achieve this balance,intraepithelial lymphocytes(IELs)that are scattered among intestinal epithelial cells carry out numerous important functions.
