The last-minute redemption of inflammatory cells in lung repair

Extract

Inflammatory cells play a central role in the pathogenesis of acute lung injury. Danger signals within the alveolar structures trigger a stereotypical response that results in the activation of an inflammatory response within alveoli and the interstitium. In addition to resident cells, the release of proinflammatory mediators, including chemoattractants, results in the recruitment of inflammatory cells from the circulation. Activated macrophages and neutrophils participate in the early phase of acute injury, mainly by promoting tissue disruption [1]. This acute response aims to remove pathogens and damaged cells in an expedited way and, if the severity of injury is mild or moderate, may result in effective repair or even regeneration. However, in case of severe damage, the intra-alveolar inflammatory response may impair lung function, worsening gas exchange and respiratory mechanics.