After the 12-week SFC therapy, the proportion of Foxp3+Tregs as a percentage of total CD4+ T cells in the peripheral blood of COPD patients significantly increased from 3.33 ± 0.23% to 4.14 ± 0.21% (p < 0.001), as analyzed by flow cytometry. This evidence concerns the gene CD4 and chronic obstructive pulmonary disease.