IL4 and chronic obstructive pulmonary disease: Compared to the asthma and COPD groups, higher levels of IL-4 (Figure 1Da), IL-6 (Figure 1Db), TNF-α (Figure 1Dc), IL-1β (Figure 1Dd), IL-17A (Figure 1De), and IFN-γ (Figure 1Df) in ACO were observed, and there were significances in IL-4, IL-6, TNF-α, and IFN-γ compared to the control group (P < 0.01).