Previous Article
Clinical and Diagnostic Laboratory Immunology, May 2003, p. 495-497, Vol. 10, No. 3
1071-412X/03/$08.00+0 DOI: 10.1128/CDLI.10.3.495-497.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.
Activation of Coagulation by Administration of Recombinant Factor VIIa Elicits Interleukin 6 (IL-6) and IL-8 Release in Healthy Human Subjects
Evert de Jonge,1* Philip W. Friederich,2 George P. Vlasuk,3 William E. Rote,3 Margaretha B. Vroom,1 Marcel Levi,2 and Tom van der Poll2,4
Departments of Intensive Care,1
Internal Medicine,2
Laboratory of Experimental Internal Medicine, Academic Medical Center, University of Amsterdam, The Netherlands,4
Corvas International, San Diego, California3
Received 18 July 2002/
Returned for modification 16 December 2002/
Accepted 21 January 2003

ABSTRACT
The activation of coagulation has been shown to contribute to
proinflammatory responses in animal and in vitro experiments.
Here we report that the activation of coagulation in healthy
human subjects by the administration of recombinant factor VIIa
also elicits a small but significant increase in the concentrations
of interleukin 6 (IL-6) and IL-8 in plasma. This increase was
absent when the subjects were pretreated with recombinant nematode
anticoagulant protein c2, the inhibitor of tissue factor-factor
VIIa.

TEXT
The activations of coagulation and inflammation during sepsis
appear to be linked in a bimodal way. While cytokines are involved
in the procoagulant state that follows endotoxemia or severe
infection, recent studies have shown that activated coagulation
factors in turn are capable of eliciting a proinflammatory response
(
9). Ex vivo clotting of human blood stimulates interleukin
8 (IL-8) and IL-6 production by monocytes and endothelial cells
(
13,
14). Recent in vitro studies have shown that several coagulation
factors, such as factor VIIa, factor Xa, and thrombin, can activate
cells directly and provoke a variety of proinflammatory responses
(
9). In this study we sought to determine whether activation
of coagulation in vivo might also elicit a proinflammatory response.
We therefore measured the cytokine response following the generation
of thrombin by the intravenous administration of factor VIIa
to healthy human subjects with and without pretreatment with
recombinant nematode anticoagulant protein c2 (rNAPc2) (Corvas
Inc., San Diego, Calif.), a potent inhibitor of the factor VIIa-tissue
factor complex (
2). Previous studies have shown that the infusion
of recombinant factor VIIa (rVIIa) leads to factor Xa-dependent
thrombin formation in chimpanzees (
21) as well as in humans
(
10). The study was performed as a double-blind, randomized,
placebo-controlled crossover study of six healthy male volunteers
(21 to 26 years of age). Treatment consisted of an intravenous
bolus injection of 90 µg of rVIIa (NovoSeven; NovoNordisk,
Copenhagen, Denmark) per kg of body weight 4 h after the subjects
received either rNAPc2 at a dose of 3.5 µg/kg as a single
subcutaneous injection or a placebo. Assays for prothrombin
activation fragment F1+2, factor X activation peptide, and the
levels of factor VIIa, tumor necrosis factor (TNF), IL-6, IL-8,
soluble TNF receptor type 1 (sTNF-R1), IL-1 receptor antagonist
(IL-1ra) and sE-selectin in plasma were performed according
to the instructions of the manufacturer and were described previously
(
8,
10,
18). Detection limits were 0.4 pmol/ml, 8.2 pg/ml, 3.2
ng/ml, 82 pg/ml, and 140 pg/ml for factor VIIa, TNF, sE-selectin,
IL-1ra, and sTNF-R1, respectively.
Values are given as means ± standard errors of the means. Differences in the results between the two treatment groups were tested by repeated-measurement analysis of variance.
The coagulant response to rVIIa and the anticoagulant effect of the factor VIIa-tissue factor inhibitor rNAPc2 have been described in detail in another report (10). We found that the levels of factor VIIa in plasma were below the limit of detection prior to the administration of rVIIa. Peak levels of 23.7 ± 2.4 nmol per liter of plasma were reached at 30 min after its administration. Pretreatment with rNAPc2 had no effect on the levels of factor VIIa in plasma (data not shown). As previously described in detail, the administration of rVIIa resulted in the substantial activation of thrombin generation, as reflected by a 3.6-fold increase in F1+2 levels to 4.0 ± 0.3 nmol/liter. Pretreatment with rNAPc2 attenuated thrombin generation (peak levels, 3.2 ± 1.5 nmol/liter; P < 0.05) (10). Maximal levels of factor X activation peptide in plasma were reached at 60 min following the administration of rVIIa. Pretreatment with rNAPc2 resulted in lower rVIIa-induced peak levels of factor X activation peptide than those resulting from the injection of rVIIa alone (from 116 ± 6 to 387 ± 6 pmol/liter after the administration of rVIIa-placebo and from 87 ± 9 pmol/liter to 302 ± 25 pmol/liter after the administration of rVIIa preceded by that of rNAPc2;, P < 0.05 for the difference in the results between the treatment groups).
Plasma IL-6 levels increased from below the limit of detection (1.2 pg/ml) at the baseline to 5.5 ± 2.5 pg/ml at 4 h after the administration of rVIIa and to 2.9 ± 1.6 pg/ml at 6 h after the administration of rVIIa preceded by that of rNAPc2 (P = 0.05 for the difference in the results between the treatment groups) (Fig. 1). The levels of IL-8 increased from <2 pg/ml to 8.3 ± 3.3 pg/ml at 6 h after the administration of rVIIa and to 3.7 ± 1.1 pg/ml at 4 h after the administration of rVIIa-rNAPc2 (P < 0.05 for the difference in the results between the treatment groups). In contrast, the levels in plasma of TNF, the cytokine inhibitors sTNF-R1 and IL-1ra, and sE-selectin (a marker for endothelial-cell activation) were not influenced by the administration of rVIIa (data not shown), but the scope of this study is clearly insufficient to exclude such an effect.
This is the first study to show that the activation of coagulation
can induce the release of cytokines in humans. Pretreatment
with the factor VIIa-tissue factor inhibitor rNAPc2 decreased
rVIIa-induced thrombin generation and prevented an increase
in circulating IL-6 and IL-8. Consistent with our observation
that release of IL-6 and IL-8 is stimulated by the rVIIa-induced
activation of coagulation, in vitro studies with human whole
blood revealed that activation of coagulation stimulates the
production of IL-8 and, to a lesser extent, IL-6, but not TNF
(
13). Furthermore, in primate models of sepsis, the levels of
IL-6 and IL-8, but not TNF, were significantly attenuated by
anticoagulant interventions with tissue factor pathway inhibitor
(
6) or antithrombin (
19). Several coagulation factors could
potentially contribute to the release of IL-6 and IL-8. The
administration of rVIIa resulted in thrombin generation, as
reflected by increased levels of F1+2. Thrombin has been shown
to stimulate the release of IL-1, IL-6, IL-8, TNF, and monocyte
chemotactic protein 1by monocytes and endothelial cells (
5,
11,
12,
14,
15,
17,
22), probably because of its catalytic activity
(
1,
14) and because of the cleavage of cell surface protease-activated
receptors (
16). Another candidate for eliciting an inflammatory
response is factor Xa. Factor Xa, by binding to effector cell
protease receptor 1 and independently of thrombin, has been
found to trigger acute inflammatory responses in animal experiments
(
4). Factor Xa was shown to stimulate cultured human endothelial
cells to produce IL-6, IL-8, monocyte chemotactic protein 1,
and the adhesion molecules sE-selectin, intercellular adhesion
molecule 1, and vascular cell adhesion molecule 1 by a mechanism
independent of thrombin and effector cell protease receptor
1 (
20). Indeed, a prolonged increase of factor X activation
peptide was found in our study following the administration
of rVIIa. Finally, factor VIIa itself could contribute to the
observed increase in cytokine levels. It has been shown that
factor VIIa, independently of other coagulation proteins, can
induce proinflammatory changes in mononuclear cells (
7), possibly
by the activation of protease-activated receptor 2 (PAR2) and
to a lesser degree PAR1 (
3). In the presence of factor Xa, low
picomolar concentrations of factor VIIa caused robust signaling
in cells expressing tissue factor and PAR2 (
3). It is worth
noting that these concentrations are much lower than the nanomolar
concentrations of factor VIIa that were measured in our experiments
after the administration of rVIIa. Our observations indicate
that activation of the coagulation response in humans can elicit
cytokine release. Clearly, this inflammatory response is small,
with IL-6 and IL-8 levels below 10 pg/ml. This limited response
could be caused by the short-term and relatively modest effect
of the intravenous bolus injection of rVIIa on thrombin generation.
A more prolonged activation of coagulation could potentially
have more influence on inflammatory responses. Furthermore,
coagulation could have a more profound effect on other inflammatory
cascades when these are already activated to some extent by
a common stimulus, such as bacterial infection or endotoxin.
Alternatively, the limited effect of rVIIa on the cytokine response
could be explained by the absence of the expression of its cofactor,
tissue factor, on the circulating cells of healthy subjects.
In situations with increased tissue factor expression on circulating
blood cells, as during severe sepsis, the activation of coagulation
could potentially induce a larger proinflammatory response.
However, in the mild inflammation model of endotoxemia in healthy
humans, in which the endotoxin-induced activation of coagulation
was prevented by the administration of tissue factor pathway
inhibitor, this inhibition of thrombin generation did not affect
the cytokine response (
8). Thus, it can be argued that the magnitude
of the inflammatory response following the activation of coagulation
could be higher in different situations. On the other hand,
the possibility cannot be excluded that the inflammatory response
is exclusively the result of very high, supraphysiological levels
of factor VIIa and thus has limited physiological relevance.
Further studies are planned to determine whether the coagulation-initiated
inflammatory response may be quantitatively relevant in clinical
situations, like sepsis, with disseminated intravascular coagulation.
In conclusion, we demonstrated that the activation of coagulation by the administration of recombinant factor VIIa can elicit both IL-6 and IL-8 responses in healthy human subjects. This cytokine response can be prevented by attenuating the activation of coagulation with the inhibitor of factor VIIa-tissue factor, rNAPc2.

FOOTNOTES
* Corresponding author. Mailing address: Department of Intensive Care, Academic Medical Center, P.O. Box 22660, 1100 DD Amsterdam, The Netherlands. Phone: 31 20 5662509. Fax: 31 20 6972988. E-mail:
e.dejonge{at}amc.uva.nl.


REFERENCES
1 - Anrather, D., M. T. Millan, A. Palmetshofer, S. C. Robson, C. Geczy, A. J. Ritchie, F. H. Bach, and B. M. Ewenstein. 1997. Thrombin activates nuclear factor-kappaB and potentiates endothelial cell activation by TNF. J. Immunol. 159:5620-5628.[Abstract]
2 - Bergum, P. W., A. Cruikshank, S. L. Maki, C. R. Kelly, W. Ruf, and G. P. Vlasuk. 2001. Role of zymogen and activated factor X as scaffolds for the inhibition of the blood coagulation factor VIIa-tissue factor complex by recombinant nematode anticoagulant protein c2. J. Biol. Chem. 276:10063-10071.[Abstract/Free Full Text]
3 - Camerer, E., W. Huang, and S. R. Coughlin. 2000. Tissue factor- and factor X-dependent activation of protease-activated receptor 2 by factor VIIa. Proc. Natl. Acad. Sci. USA 97:5255-5260.[Abstract/Free Full Text]
4 - Cirino, G., C. Cicala, M. Bucci, L. Sorrentino, G. Ambrosini, G. DeDominicis, and D. C. Altieri. 1997. Factor Xa as an interface between coagulation and inflammation. Molecular mimicry of factor Xa association with effector cell protease receptor-1 induces acute inflammation in vivo. J. Clin. Investig. 99:2446-2451.[Medline]
5 - Colotta, F., F. L. Sciacca, M. Sironi, W. Luini, M. J. Rabiet, and A. Mantovani. 1994. Expression of monocyte chemotactic protein-1 by monocytes and endothelial cells exposed to thrombin. Am. J. Pathol. 144:975-985.[Abstract]
6 - Creasey, A. A., A. C. Chang, L. Feigen, T. C. Wun, F. B. J. Taylor, and L. B. Hinshaw. 1993. Tissue factor pathway inhibitor reduces mortality from Escherichia coli septic shock. J. Clin. Investig. 91:2850-2856.
7 - Cunningham, M. A., P. Romas, P. Hutchinson, S. R. Holdsworth, and P. G. Tipping. 1999. Tissue factor and factor VIIa receptor/ligand interactions induce proinflammatory effects in macrophages. Blood 94:3413-3420.[Abstract/Free Full Text]
8 - de Jonge, E., P. E. P. Dekkers, A. A. Creasey, C. E. Hack, S. K. Paulson, A. Karim, J. Kesecioglu, M. Levi, S. J. van Deventer, and T. van der Poll. 2000. Tissue factor pathway inhibitor (TFPI) dose-dependently inhibits coagulation activation without influencing the fibrinolytic and cytokine response during human endotoxemia. Blood 95:1124-1129.[Abstract/Free Full Text]
9 - Esmon, C. T. 2000. Introduction: are natural anticoagulants candidates for modulating the inflammatory response to endotoxin? Blood 95:1113-1116.[Free Full Text]
10 - Friederich, P. W., M. Levi, K. A. Bauer, G. P. Vlasuk, W. E. Rote, D. Breederveld, T. Keller, M. Spataro, S. Barzegar, and H. R. Buller. 2001. The ability of recombinant factor VIIa to generate thrombin during inhibition of tissue factor in human subjects. Circulation 103:2555-2559.[Abstract/Free Full Text]
11 - Grandaliano, G., A. J. Valente, and H. E. Abboud. 1994. A novel biologic activity of thrombin: stimulation of monocyte chemotactic protein production. J. Exp. Med. 179:1737-1741.[Abstract/Free Full Text]
12 - Hoffman, M., and S. T. Cooper. 1995. Thrombin enhances monocyte secretion of tumor necrosis factor and interleukin-1 beta by two distinct mechanisms. Blood Cells Mol. Dis. 21:156-167.
13 - Johnson, K., L. Aarden, Y. Choi, E. De Groot, and A. Creasey. 1996. The proinflammatory cytokine response to coagulation and endotoxin in whole blood. Blood 87:5051-5060.[Abstract/Free Full Text]
14 - Johnson, K., Y. Choi, E. DeGroot, I. Samuels, A. Creasey, and L. Aarden. 1998. Potential mechanisms for a proinflammatory vascular cytokine response to coagulation activation. J. Immunol. 160:5130-5135.[Abstract/Free Full Text]
15 - Jones, A., and C. L. Geczy. 1990. Thrombin and factor Xa enhance the production of interleukin-1. Immunology 71:236-241.[Medline]
16 - Kahn, M. L., M. Nakanishi-Matsui, M. J. Shapiro, H. Ishihara, and S. R. Coughlin. 1999. Protease-activated receptors 1 and 4 mediate activation of human platelets by thrombin. J. Clin. Investig. 103:879-887.[Medline]
17 - Kranzhofer, R., S. K. Clinton, K. Ishii, S. R. Coughlin, J. W. Fenton II, and P. Libby. 1996. Thrombin potently stimulates cytokine production in human vascular smooth muscle cells but not in mononuclear phagocytes. Circ. Res. 79:286-294.[Abstract/Free Full Text]
18 - Leeuwenberg, J. F., E. F. Smeets, J. J. Neefjes, M. A. Shaffer, T. Cinek, T. M. Jeunhomme, T. J. Ahern, and W. A. Buurman. 1992. E-selectin and intercellular adhesion molecule-1 are released by activated human endothelial cells in vitro. Immunology 77:543-549.[Medline]
19 - Minnema, M. C., A. C. Chang, P. M. Jansen, Y. T. Lubbers, B. M. Pratt, B. G. Whittaker, F. B. Taylor, C. E. Hack, and B. Friedman. 2000. Recombinant human antithrombin III improves survival and attenuates inflammatory responses in baboons lethally challenged with Escherichia coli. Blood 95:1117-1123.[Abstract/Free Full Text]
20 - Senden, N. H. M., T. M. A. A. Jeunhomme, J. W. M. Heemskerk, R. Wagenvoord, C. van 't Veer, H. Coenraad Hemker, and W. A. Buurman. 1998. Factor Xa induces cytokine production and expression of adhesion molecules by human umbilical vein endothelial cells. J. Immunol. 161:4318-4324.[Abstract/Free Full Text]
21 - ten Cate, H., K. A. Bauer, M. Levi, T. S. Edgington, R. D. Sublett, S. Barzegar, B. L. Kass, and R. D. Rosenberg. 1993. The activation of factor X and prothrombin by recombinant factor VIIa in vivo is mediated by tissue factor. J. Clin. Investig. 92:1207-1212.
22 - Ueno, A., K. Murakami, K. Yamanouchi, M. Watanabe, and T. Kondo. 1996. Thrombin stimulates production of interleukin-8 in human umbilical vein endothelial cells. Immunology 88:76-81.[CrossRef][Medline]
Clinical and Diagnostic Laboratory Immunology, May 2003, p. 495-497, Vol. 10, No. 3
1071-412X/03/$08.00+0 DOI: 10.1128/CDLI.10.3.495-497.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.
This article has been cited by other articles:
-
Sass, C., Blanquart, C., Morange, P.-E., Pfister, M., Visvikis-Siest, S.
(2004). Association Between Factor VII Polymorphisms and Blood Pressure: The Stanislas Cohort. Hypertension
44: 674-680
[Abstract]
[Full Text]
-
Levi, M., van der Poll, T., Buller, H. R.
(2004). Bidirectional Relation Between Inflammation and Coagulation. Circulation
109: 2698-2704
[Full Text]