Figure 4.

(a) Western blot analysis of biomarkers in induced sputum samples from seven healthy smokers and seven smokers with stage 2 chronic obstructive pulmonary disease (COPD II). Experimental molecular masses of the major band are shown. Arrows indicate predicted direction of change in patients with COPD from two-dimensional gel electrophoresis data. α-2-HS glycoprotein = α₂-Heremans–Schmid glycoprotein; HS = healthy smokers; PLUNC = palate, lung, and nasal epithelium clone protein; PSP94 = prostate secretory protein of 94 amino acids. (b) Densitometry analysis of results from the Western blot, indicating significance of change between the two groups compared by Student t test (denoted by brackets: P < 0.05).