In this study, we hypothesized that SFC alleviated inflammation in patients with COPD by increasing the percentage of Foxp3+Tregs in the peripheral blood to enhance immune tolerance, thereby reducing the total numbers of cells and neutrophils in induced sputum, and reducing the levels of inflammatory factors such as IL-8, TNF-α, and IL-17A. The gene discussed is IL17A; the disease is chronic obstructive pulmonary disease.