Inflammasome Activation in Acute Lung Injury

Inflammasomes are multi-protein complexes tasked with sensing endogenous or exogenous inflammatory signals, and integrating this signal into a downstream response. Inflammasome activation has been implicated in a variety of pulmonary diseases, including pulmonary hypertension, bacterial pneumonia, COPD and asthma. Of increasing interest is the contribution of inflammasome activation in the context of acute lung injury/acute respiratory distress syndrome (ALI/ARDS). Inflammasome activation in both the lung parenchyma and resident immune cells generates intereukin-1β (IL-1β) and IL-18, both of which drive the cascade of lung inflammation forward. Blockade of these responses has been shown to be beneficial in animal models, and is a focus of translational research in the field. In this review, we will discuss the assembly and regulation of inflammasomes during lung inflammation, highlighting therapeutically-viable effector steps. We will examine the importance of IL-1β and IL-18, two key products of inflammasome activation, in ALI, as well as the contribution of the pulmonary endothelial cell to this process. Finally, we will explore translational research moving toward anti-inflammasome therapies for ALI/ARDS, and speculate toward future directions for the field.