IL17A and chronic obstructive pulmonary disease: COPD is characterized by chronic inflammation in the airways and lung tissues, leading to thickening of airway walls and hyperplasia of mucous glands, further leading to airway obstruction, luminal narrowing, and hypercontractility of airway smooth muscle to restrict airflow and exacerbate pulmonary injury.[23] IL-6, IL-17, and LTB4 function as key pro-inflammatory cytokines that critically regulate inflammatory and immune processes.