FIG 5.

Illustration of mature and immature intestinal barriers in neonates. Peristalsis (reduced intestinal motility), maldigestion of nutrient sources, and a compromised gut barrier may render the mucosa susceptible to invasion by opportunistic pathogens in the gut environment. The resulting imbalance between epithelial cell injury and repair leads to a vicious cycle of maldigestion, bacterial invasion, immune activation, and uncontrolled inflammation. The illustration is not drawn to scale. (Created with BioRender.com.)