CXCL8 and pulmonary emphysema: Proteases released by neutrophils (including elastase, matrix metalloproteinases, and cathepsins) are core pathological mediators, elastase directly degrades elastic and collagen fibers in alveolar walls, promoting the formation of pulmonary emphysema; these proteases amplify the inflammatory cascade by activating inflammatory mediators such as IL-8 and TNF-αand disrupting theα1-antitrypsin barrier; simultaneously, they induce airway smooth muscle proliferation and fibrosis, leading to airway remodeling and progressive airflow limitation (145).