TLR4 and necrotizing enterocolitis: We have shown that TLR4 expression on the lung epithelium is required for the recruitment of proinflammatory neutrophils into the lung through the upregulation of CCL25 (50, 51), and that strategies to either inhibit TLR4 via the administration of aerosolized inhibitors, or through genetic deletion, can serve as novel lung protective strategies in the setting of NEC (50).