ACTA1 and chronic obstructive pulmonary disease: Western analysis showed that cells isolated from peripheral lung of the smokers without COPD (0.40, SD 0.38) or COPD (0.39, SD 0.31) expressed a 0.70-fold lower amount of α-SMA compared to non-smoking individuals (0.56, SD 0.35) even though the statistical difference was not significant (Figure 5).