ABSTRACT
The small intestinal barrier plays a significant role in protecting the premature infant from necrotizing enterocolitis (NEC). The epithelium provides both a physical barrier and highly specialized immune functions to protect the host. Moreover, the epithelial layer is in constant flux with programmed cellular turnover, and disruption of individual cell types may play a role in NEC development. In NEC and other inflammatory diseases of the intestine, disruption of the cellular junctions appears to be a critical step in pathogenesis. This chapter aims to provide an understanding of the role of the epithelial barrier in the development of NEC.
