PTGES and asthma: In Ptges-deficient mice, the decrease in anti-allergic PGE2 allows excessive production of pro-allergic cys-LTs and other PGs, leading to aspirin hypersensitivity and airway inflammation similar to aspirin-induced asthma in humans (12), highlighting that mPGES-1-derived PGE2 plays a crucial role in maintaining lung homeostasis.