IL6 and primary ciliary dyskinesia: Macrophages stimulated with PCD sputum exhibited enhanced phagocytosis (MFI 194268 vs. 58235, p = 0.0002), increased expression of M2-associated surface markers CD163, CD206 and CD16, and reduced secretion of proinflammatory cytokines IL-6 (10.38 vs. 113.22 pg/ml, p = 0.0013) and IL-1β (0.75 vs. 3.60 pg/ml, p < 0.0001).