Figure 8From: Variability in the precursor proteins of collagen I and III in different stages of COPD Precursor protein of collagen III in the small airways of non-smokers, smokers and the patients with COPD. The subepithelial area with positive staining for precursor protein of collagen III was thinner in severe COPD compared to non-smokers (p = 0.017), smokers (p = 0.045) and patients with stage I-II COPD (p = 0.012).Back to article page