MPs were isolated from the sputum of mild to severe COPD patients and were positive for CD66b (granulocytes), CD235ab (erythrocytes), CD31 (platelets/endothelial cell adhesion molecules 1), CD41 (platelets/megakaryocytes), and CD11a (leukocytes).There was a negative correlation between CD31-MPs and FEV1, whereas CD66b-MPs were correlated with a worse COPD performance index. Here, PECAM1 is linked to chronic obstructive pulmonary disease.