Taken together, these results show the anti-inflammatory effects of inhibiting VAP-1/SSAO enzymatic function and highlight the potential of PXS-4728A as a novel therapeutic tool in diseases that are characterized by a neutrophilic pattern of inflammation, including acute lung injury, chronic obstructive pulmonary disease, cystic fibrosis, and bronchiolitis obliterans syndrome. Here, AOC3 is linked to bronchiolitis obliterans syndrome.