Chemokines (CCL3, CCL4, and CCL5) Inhibit ATP-Induced Release of IL-1β by Monocytic Cells

Autor: Anca-Laura Amati, Anna Zakrzewicz, Kathrin Siebers, Sigrid Wilker, Sarah Heldmann, Dariusz Zakrzewicz, Andreas Hecker, J. Michael McIntosh, Winfried Padberg, Veronika Grau
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Zdroj: Mediators of Inflammation, Vol 2017 (2017)
Druh dokumentu: article
ISSN: 0962-9351
1466-1861
DOI: 10.1155/2017/1434872
Popis: Chemokines and ATP are among the mediators of inflammatory sites that can enter the circulation via damaged blood vessels. The main function of chemokines is leukocyte mobilization, and ATP typically triggers inflammasome assembly. IL-1β, a potent inflammasome-dependent cytokine of innate immunity, is essential for pathogen defense. However, excessive IL-1β may cause life-threatening systemic inflammation. Here, we hypothesize that chemokines control ATP-dependent secretion of monocytic IL-1β. Lipopolysaccharide-primed human monocytic U937 cells were stimulated with the P2X7 agonist BzATP for 30 min to induce IL-1β release. CCL3, CCL4, and CCL5 dose dependently inhibited BzATP-stimulated release of IL-1β, whereas CXCL16 was ineffective. The effect of CCL3 was confirmed for primary mononuclear leukocytes. It was blunted after silencing CCR1 or calcium-independent phospholipase A2 (iPLA2) by siRNA and was sensitive to antagonists of nicotinic acetylcholine receptors containing subunits α7 and α9. U937 cells secreted small factors in response to CCL3 that mediated the inhibition of IL-1β release. We suggest that CCL chemokines inhibit ATP-induced release of IL-1β from U937 cells by a triple-membrane-passing mechanism involving CCR, iPLA2, release of small mediators, and nicotinic acetylcholine receptor subunits α7 and α9. We speculate that whenever chemokines and ATP enter the circulation concomitantly, systemic release of IL-1β is minimized.
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