Of note, the reduction of the proinflammatory molecule CXCL1, a potent chemoattractant of neutrophils [28–30], in BAL and in the serum of COPD+Exe group could putatively lead to the reduction of neutrophil migration and activation in airways and consequently minimize the damage of chronic exposition of cigarette smoke in the lung. Here, CXCL1 is linked to chronic obstructive pulmonary disease.