Effect of cytokines and colony-stimulating factors on passive polymorphonuclear leukocyte deformability in vitro

Cytokines are potent polymorphonuclear leukocyte (PMN) activators and can decrease their deformability. We evaluated passive PMN deformability using the micropipette method after incubation with different concentrations of lipopolysaccharide (LPS), interleukins (IL-) 1, 6, 8 and 10, tumour necrosis factor (TNF), granulocyte (G) and granulocyte-macrophage (GM) colony-stimulating factors (CSF). TNF, IL-1, G-CSF, GM-CSF and, to a lesser degree, IL-6 significantly and in a dose-dependent fashion decrease PMN deformability. LPS had no direct effect on PMN deformability. When cytokines at concentrations with no effect on deformability were combined they increased PMN rigidity. The findings suggest that several cytokines and CSF impair directly, and not by activation alone, PMN deformability.