CD163, CD204 and CD206 immunohistochemical staining of lung tissue samples from a non-smoker, a smoker, a mild chronic obstructive pulmonary disease patient (COPD), and a very severe COPD.

<p>(A) Positive reactivity was identified by 3–3′-diaminobenzidine-4HCl (DAB). Bar: 50 µm. (B) Double immunohistochemical analysis for CD163/CD204, CD163/CD206 and CD206/CD204. Lung tissues were obtained from a very severe COPD. CD163 (brown)/CD204 (green), CD163 (brown)/CD206 (green) and CD206 (brown)/CD204 (green) were double stained with DAB (brown) and HistoGreen (green), respectively. Bar: 50 µm.