Formoterol exerted pro-inflammatory effects on IL-8, GM-CSF and IL-1β secretion in both peripheral blood and sputum neutrophils from healthy controls and COPD patients (Fig. 2b, Additional file 2: Figure SE1 and Additional file 1: Table SE1), while salmeterol showed weak inhibitory or pro-inflammatory effects depending on the measured cytokine (Fig. 2b, Additional file 2: Figure SE1 and Additional file 1: Table SE1). Here, CSF2 is linked to chronic obstructive pulmonary disease.