Synergy between tumour necrosis factor α and granulocyte-macrophage colony-stimulating factor in neutrophil stimulation

Abstract

We have examined the interaction between the cytokines, granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumour necrosis factor α (TNFα) on polymorphonuclear leukocyte (PMN) function and on PMN responses to further stimulation with formyl Met Leu Phe (fMLP). Incubation of PMN with TNFα (0.3 n M) and, to a lesser extent, with GM-CSF (1 n M) directly stimulated superoxide anion (O2-) generation and increased the response to subsequent stimulation of PMN by fMLP (100 n M). However, the combination of GM-CSF and TNFα did not result in increased O2- generation and there was no synergistic effect of the combination of these cytokines on the priming of fMLP-induced O2- generation. The ..