ITGAM and chronic obstructive pulmonary disease: We then examined the expression of each of phagocytosis-associated receptors (FcγRI, CD11b, MSR-1, CD36 and Siglec-1) on the surface of FSChi/SSChi/CD45+/CD206+ alveolar macrophages in flow-cytometry, that were collected from lung tissues of CNS (n = 11), CES (n = 9) and COPD with mild-to-moderate airflow limitation severity (n = 5 in GOLD stage1, n = 6 in GOLD stage2).