IL-10 inhibits LPS-induced human monocyte tissue factor expression in whole blood.
Interleukin 4 (IL-4), IL-10 and IL-13 are all known to modulate several proinflammatory functions in human monocytes. They have also previously been shown to down-regulate lipopolysaccharide (LPS)-induced tissue factor (TF) expression in isolated cultured monocytes. In this study we investigated the effect of these three cytokines on the induction of monocytic TF in a whole blood environment at three levels: mRNA quantitation, surface antigen expression and procoagulant activity. We showed that IL-10 attenuated LPS-induced monocyte TF expression and activity in whole blood in a concentration-dependent manner, both when added to the blood prior to LPS and, although to a lesser extent, when added up to 1 h subsequent to LPS challenge. Maximum inhibition occurred at 5 ng/ml of IL-10 when the cytokine was added before LPS. IL-4 and IL-13, however, did not exhibit any inhibitory effect in the whole blood environment, contrary to the reported findings in cell culture experiments. Our results confirm the potential of IL-10 as an anti-inflammatory, TF-preventing drug, whereas the effects of IL-4 and IL-13 on monocytes in whole blood seem more complex, and require further investigation.
Lindmark
E
E
Department of Clinical Chemistry, University Hospital, Uppsala, Sweden.
Tenno
T
T
Chen
J
J
Siegbahn
A
A
D015536:Down-Regulation; D005434:Flow Cytometry; D006801:Humans; D016753:Interleukin-10 / Q000494:pharmacology*; D018793:Interleukin-13 / Q000494:pharmacology; D015847:Interleukin-4 / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology*; D009000:Monocytes / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D013925:Thromboplastin / Q000378:metabolism*
D018793:Interleukin-13; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D016753:Interleukin-10; D015847:Interleukin-4; D013925:Thromboplastin