Monocyte IL-10 produced in response to lipopolysaccharide modulates thrombin generation by inhibiting tissue factor expression and release of active tissue factor-bound microparticles.
Lipopolysaccharide (LPS)-stimulated monocytes are known to have a procoagulant effect. This property is currently explained by the fact that monocytes, in response to LPS, can express tissue factor (TF) and undergo a process of membrane microvesiculation. Interleukin-10 (IL-10) has been shown to downregulate TF expression and inhibit procoagulant activity (PCA). In order to further characterize the inhibitory effect of IL-10 on LPS-induced PCA, we used the integrated system of analysis of kinetics of thrombin generation in normal plasma (thrombinography). For this, we developed an original method of elutriation allowing to obtain a highly purified monocyte preparation, under endotoxin-free conditions. Thrombin generation was measured using a highly sensitive and specific fluorogenic method which we adapted to inhibit the contact factor pathway. Results show that recombinant human IL-10 decreased the kinetics of thrombin generation in a dose-dependent manner. Furthermore, the inhibition of endogenous IL-10 released by monocytes in response to LPS is associated with an increase in the kinetics of thrombin generation. We demonstrated that this effect was a consequence of the up-regulation of TF expression and TF-bound microparticle release. In conclusion, we report that IL-10 can regulate thrombin generation in conditions close to physiology as allowed by thrombinography, and that endogenous IL-10 regulates TF expression and release of active TF-bound microparticles by a negative feed back loop through IL-10 receptor alpha.
Poitevin
Stéphane
S
Laboratoire Central d'Hématologie, Hôpital Robert Debré, Avenue du Général Koenig, Reims Cedex, France.
Cochery-Nouvellon
Eva
E
Dupont
Annick
A
Nguyen
Philippe
P
D000911:Antibodies, Monoclonal; D001779:Blood Coagulation Factors / Q000037:antagonists & inhibitors / Q000378:metabolism*; D002469:Cell Separation / Q000379:methods; D002478:Cells, Cultured; D022162:Cytoplasmic Vesicles / Q000187:drug effects* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D025461:Feedback, Physiological; D005470:Fluorometry / Q000379:methods; D015870:Gene Expression / Q000187:drug effects*; D006801:Humans; D016753:Interleukin-10 / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D053709:Interleukin-10 Receptor alpha Subunit / Q000276:immunology / Q000378:metabolism; D007700:Kinetics; D008070:Lipopolysaccharides / Q000494:pharmacology*; D009000:Monocytes / Q000187:drug effects* / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D013917:Thrombin / Q000378:metabolism*; D013925:Thromboplastin / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D013997:Time Factors
D000911:Antibodies, Monoclonal; D001779:Blood Coagulation Factors; C508609:IL10 protein, human; D053709:Interleukin-10 Receptor alpha Subunit; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D011994:Recombinant Proteins; C045071:leukocyte procoagulant activity; C482199:lipopolysaccharide, E coli O55-B5; D016753:Interleukin-10; D013925:Thromboplastin; D013917:Thrombin