Understanding Idiopathic Interstitial Pneumonia: A Gene-Based Review of Stressed Lungs

Figure 1

Hypothesized scheme of increased mechanical stress in MUC5B risk allele carriers. At areas with maximal mechanical stress in the lung, optimal surface tension lowering capacity of alveolar surfactant fluid is required. Through breathing mechanics admixture of alveolar and airway surfactant occurs. Increased amounts of MUC5B protein in MUC5B risk allele carriers have detrimental effect on surface tension lowering capacity of the alveolar surfactant fluid. In case of suboptimal surfactant, inflation requires increased traction on the alveolar wall and induces epithelial damage. Alveolar repair causes high epithelial cell turnover with consequent critical shortening of telomeres, which in turn induce senescence of alveolar epithelial type II cells.