GSK3B and chronic obstructive pulmonary disease: Phospho-GSK3β-Ser9 staining was higher in lung tissue macrophages of COPD patients (70.5 ± 4.1% positive) than in control smokers (46.5 ± 6.2, P < 0.01) and nonsmokers (19.3 ± 3.8, P < 0.001) and was also higher in control smokers than nonsmokers (Fig. 1, A and B).