Non-septic Acute Lung Injury and Inflammation: Role of TLR4

Although the role of Toll-like receptor 4 (TLR4) in bacterial infection and sepsis is well characterized, recent studies have also shown that TLR4 can play an important role in contributing to acute inflammatory processes and organ dysfunction in settings in which lipopolysaccharide (LPS) or other bacterial products are not present. In particular, there is increasing evidence that TLR4 is not just a receptor for LPS, but can also transduce other pro-inflammatory signals and, thereby, contribute to cellular activation leading to acute lung injury (ALI) and other organ system dysfunction.