T Regulatory Mechanisms in Airway and Interstitial Lung Disease.

Chronic lung disease is a sequela of unresolving pathogenesis in the lung. Current estimates report approximately 7.4% of the world's population live with chronic respiratory diseases. The architectural differences in the airways and individual alveoli provide unique microenvironments for mechanisms of disease and thus necessitate specialized modes of regulation. A key immune cell type that has the ability to adapt and provide copius regulatory mechanisms are T regulatory cells (Tregs). In the last two decades, studies have revealed that Tregs respond to their microenvironment and phenotypically change to conduct versatile functions; however, during chronic inflammatory diseases, Tregs are potentially skewed toward pathogenic mechanisms. In this review, we will focus on the differential mechanisms of Treg responses in the lung airways versus interstitium as unique microenvironments by focusing on asthma, acute lung injury/airway respiratory disease syndrome, and interstitial lung disease.