 |
|
Prevention of Endotoxin-Induced Mortality by Antitissue Factor Immunization
Alan P. B. Dackiw, MD;
Ian D. McGilvray, MD;
Michael Woodside;
Avery B. Nathens, MD;
John C. Marshall, MD;
Ori D. Rotstein, MD
Arch Surg. 1996;131(12):1273-1279.
Abstract
Background
Microvascular thrombosis with intravascular fibrin deposition is a characteristic pathologic alteration during endotoxic shock. This effect is predominantly mediated by expression of the cellular procoagulant tissue factor by endothelial cells and cells of monocyte or macrophage lineage, resulting in acceleration of the coagulation cascade and fibrin deposition.
Objective
To determine whether modulation of this response by treatment with an antitissue factor antibody might have beneficial effects.
Design
A polyclonal antibody to murine tissue factor was prepared by injecting rabbits with a synthesized peptide sequence of murine tissue factor. To determine the activity of the antibody, elicited murine peritoneal macrophages were treated for 4 hours with 10-µg/mL lipopolysaccharide (LPS), and procoagulant activity was determined via a clotting assay (milliunits of activity per 106 macrophages).
Results
The tissue factor antibody abrogated LPS-induced macrophage procoagulant activity, confirming activity of the antibody (macrophages, 236±28 mU/106 macrophages; macrophages/LPS, 3801±190* mU/106 macrophages; macrophages/LPS/ -tissue factor, 753±92* mU/106 macrophages; n=3; the asterisk indicates P<.05 by an analysis of variance). Additionally, antibody-protein affinity was confirmed by Western blot analysis. Having determined the activity of the antibody in vitro, we tested its efficacy in vivo in a lethal endotoxemia model. Mice were immunized with 200 µL of antiserum intraperitoneally 2 hours before injection with 250 µg of LPS intraperitoneally and 24 hours later. Control animals received 200 µL of saline solution. All animals initially exhibited lethargy and piloerection, characteristic of the predicted response to LPS. However, immunized animals had a significantly (P<.05) reduced mortality compared with control animals. Fibrinogen levels were significantly (P<.05) higher in the immunized mice, suggesting decreased consumption of coagulation factors, a finding consistent with an antitissue factor effect. Further, plasma tumor necrosis factor levels 90 minutes after LPS injection were similar in both groups, suggesting normal induction of the cytokine cascade.
Conclusions
Modulation of microvascular fibrin deposition by abrogating tissue factor—mediated coagulation significantly (P<.05) improved survival in this model without attenuating the initiation of the cytokine cascade. These findings suggest a pathogenic role for coagulation in the induction of acute organ injury during sepsis.
Arch Surg. 1996;131:1273-1279
Author Affiliations
From the Department of Surgery, The Toronto Hospital, the University of Toronto, and The Toronto Hospital Research Institute, Toronto, Ontario.
 CiteULike  Connotea  Delicious  Digg  Facebook  Reddit  Technorati  Twitter
What's this?
THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES
|
Inhibition of intravascular thrombosis in murine endotoxemia by targeted expression of hirudin and tissue factor pathway inhibitor analogs to activated endothelium
Chen et al.
Blood 2004;104:1344-1349.
ABSTRACT
| FULL TEXT
Accumulation of Tissue Factor into Developing Thrombi In Vivo Is Dependent upon Microparticle P-Selectin Glycoprotein Ligand 1 and Platelet P-Selectin
Falati et al.
JEM 2003;197:1585-1598.
ABSTRACT
| FULL TEXT
Regulation of tissue factor and inflammatory mediators by Egr-1 in a mouse endotoxemia model
Pawlinski et al.
Blood 2003;101:3940-3947.
ABSTRACT
| FULL TEXT
The in vivo kinetics of tissue factor messenger RNA expression during human endotoxemia: relationship with activation of coagulation
Franco et al.
Blood 2000;96:554-559.
ABSTRACT
| FULL TEXT
Lipopolysaccharide Induction of Tissue Factor Expression in Rabbits
Erlich et al.
Infect. Immun. 1999;67:2540-2546.
ABSTRACT
| FULL TEXT
|
