Dorte Christiansen - Academia.edu (original) (raw)
Papers by Dorte Christiansen
Immunobiology, Oct 1, 2016
Immunopharmacology, Aug 1, 2000
Apmis, Mar 25, 2018
Title: Granulocyte and monocyte CD11b expression during plasma separation is dependent on complem... more Title: Granulocyte and monocyte CD11b expression during plasma separation is dependent on complement factor 5 (C5)-an ex vivo study with blood from a C5 deficient individual. Running head: CD11b expression depends on C5.
Thrombosis and Haemostasis, 1999
Platelet compatibility after coating an artificial material with functionally active heparin was ... more Platelet compatibility after coating an artificial material with functionally active heparin was investigated. Blood was circulated in uncoated or heparin coated PVC tubing. In one hour platelet counts decreased from 155 (113-184)x10(9)/l to 124 (100-148)x10(9)/l with uncoated compared to 164 (132-192)x10(9)/l with heparin coated tubing (intergroup p = 0.02). Beta-thromboglobulin increased from 116 (80-148) microg/l to 1039 (757-1298) microg/l with uncoated and to 352 (229-638) microg/l with heparin coated tubing (intergroup p = 0.005). Platelet counts and beta-thromboglobulin correlated closely with complement activation. Solid-phase enzyme immunoassay demonstrated substantial deposition of CD42a/GPIbIX and CD61/GPIIIa on uncoated, but not on heparin coated tubing (intergroup p<0.0005). Scanning electron microscopy demonstrated activated platelets and aggregates on uncoated in contrast to heparin coated tubing, where scattered, unactivated platelets were found. Changes in P-selectin and microparticles were minor. In conclusion, this heparin surface substantially improved platelet compatibility. Markers of choice for in vitro evaluation were platelet counts, beta-thromboglobulin and platelet deposition.
Proceedings of the National Academy of Sciences of the United States of America, Sep 15, 2009
Complement component C5 is crucial for experimental animal inflammatory tissue damage; however, i... more Complement component C5 is crucial for experimental animal inflammatory tissue damage; however, its involvement in human inflammation is incompletely understood. The responses to Gram-negative bacteria were here studied taking advantage of human genetic complement-deficiencies-nature's own knockouts-including a previously undescribed C5 defect. Such deficiencies provide a unique tool for investigating the biological role of proteins. The experimental conditions allowed cross-talk between the different inflammatory pathways using a whole blood model based on the anticoagulant lepirudin, which does not interfere with the complement system. Expression of tissue factor, cell adhesion molecules, and oxidative burst depended highly on C5, mediated through the activation product C5a, whereas granulocyte enzyme release relied mainly on C3 and was C5a-independent. Release of cytokines and chemokines was mediated to varying degrees by complement and CD14; for example, interleukin (IL)-1 and IL-8 were more dependent on complement than IFN-␥ and IL-6, which were highly dependent on CD14. IL-1 receptor antagonist (IL-1ra) and IFN-␥ inducible protein 10 (IP-10) were fully dependent on CD14 and inversely regulated by complement, that is, complement deficiency and complement inhibition enhanced their release. Granulocyte responses were mainly complement-dependent, whereas monocyte responses were more dependent on CD14. Notably, all responses were abolished by combined neutralization of complement and CD14. The present study provides important insight into the comprehensive role of complement in human inflammatory responses to Gram-negative bacteria.
Immunobiology, Nov 1, 2012
, CFHR5) are also reported in MPGN II patients. Here we report two related MPGN II patients, who ... more , CFHR5) are also reported in MPGN II patients. Here we report two related MPGN II patients, who present decreased C3 plasma level and increased Ba values in the early stages of disease, but lack C3 nephritic factor (C3 Nef), factor H, C3b and factor B autoantibodies. Multiplex ligation dependent probe amplification (MLPA) identified a heterozygous chromosomal deletion of exons IV and V in the CFHR2 gene. In addition, the chromosomal breakpoint in CFHR2 intron III and deletion of a 5.3 kb genomic segment spanning from the CFHR2 to CFHR5 was identified by inverse-nested PCR. Rearrangement of CFHR2/CFHR5 region results in expression of a novel 65-70 kDa protein doublet secreted in plasma which represents differently glycosylated forms of a hybrid protein, including SCRs 1-2 of CFHR2 and all 9 SCRs of CFHR5. To address the function of the novel hybrid protein a recombinant hybrid rCFHR21-2-CFHR5 was expressed and the mutant protein was purified from plasma of the two patients. rCFHR21-2-CFHR5 bound to C3 and C3 activation fragments, caused deregulation of the C3 convertase and enhanced enzyme activity in form of C3a generation. Moreover, rCFHR21-2-CFHR5 stimulated AP in normal human serum and caused C3b accumulation on surfaces. In conclusion, we define a new genetic cause for MPGN II/DDD based on a chromosomal deletion in the CFHR gene cluster and expression of a CFHR2/CFHR5 gene protein. Defective AP regulation by the hybrid protein apparently explains deposition of C3 fragments at the GBM and consequently development of MPGN II. This defective regulation by the new hybrid protein provides fundamental insights into the pathomechanism of MPGN II and is relevant to define the appropriate therapy for the patients.
The Journal of Immunology
The complement system is an intricate cascade of the innate immune system and plays a key role in... more The complement system is an intricate cascade of the innate immune system and plays a key role in microbial defense, inflammation, organ development, and tissue regeneration. There is increasing interest in developing complement regulatory and inhibitory agents to treat complement dysfunction. In this study, we describe the nanobody hC3Nb3, which is specific for the C-terminal C345c domain of human and mouse complement component C3/C3b/C3c and potently inhibits C3 cleavage by the alternative pathway. A high-resolution structure of the hC3Nb3–C345c complex explains how the nanobody blocks proconvertase assembly. Surprisingly, although the nanobody does not affect classical pathway–mediated C3 cleavage, hC3Nb3 inhibits classical pathway–driven hemolysis, suggesting that the C-terminal domain of C3b has an important function in classical pathway C5 convertase activity. The hC3Nb3 nanobody binds C3 with low nanomolar affinity in an SDS-resistant complex, and the nanobody is demonstrated...
Molecular Immunology, Oct 1, 2008
Human astroviruses (HAstVs) constitute a family of nonenveloped, RNA viruses that cause non-infla... more Human astroviruses (HAstVs) constitute a family of nonenveloped, RNA viruses that cause non-inflammatory gastroenteritis, predominantly in infants. While HAstVs represent a significant public health concern, very little is known about the host immune response to these viruses. The HAstV capsid is initially assembled from multiple copies of the coat protein (CP) precursor and we have previously demonstrated that purified HAstV CP specifically binds to C1q resulting in inhibition of classical pathway activity. To further analyze the precise mechanism of inhibition, we examined the suppression of C1 activity by CP. CP was found to inhibit the activation of C1s and downstream complement activation (C5a) in the presence of heat-aggregated IgG, a potent classical pathway activator. CP dose-dependently bound to C1q, the isolated globular heads and the collagen-like regions of the C1q molecule and formed complexes with C1q in solution. Given the structural and functional relatedness of C1q and MBL, we subsequently investigated the interactions between CP and MBL. CP bound to purified MBL and was able to inhibit mannan-mediated activation of the lectin pathway as well. Finally, given the evolutionarily conserved nature of mammalian complement factors, we investigated whether CP was able to cross the species barrier and inhibit complement activation in rodent serum. CP inhibited complement activation in rat serum demonstrating dose-dependent inhibition of C3 activation and MAC formation. Together, our data demonstrates that HAstV CP is a novel complement inhibitor that binds C1q and MBL to suppress activation of both the classical and lectin pathways of complement.
Frontiers in Immunology, 2022
IntroductionAir embolism may complicate invasive medical procedures. Bubbles trigger complement C... more IntroductionAir embolism may complicate invasive medical procedures. Bubbles trigger complement C3-mediated cytokine release, coagulation, and platelet activationin vitroin human whole blood. Since these findings have not been verifiedin vivo, we aimed to examine the effects of air embolism in pigs on thromboinflammation.MethodsForty-five landrace pigs, average 17 kg (range 8.5-30), underwent intravenous air infusion for 300 or 360 minutes (n=29) or served as sham (n=14). Fourteen pigs were excluded due to e.g. infections or persistent foramen ovale. Blood was analyzed for white blood cells (WBC), complement activation (C3a and terminal C5b-9 complement complex [TCC]), cytokines, and hemostatic parameters including thrombin-antithrombin (TAT) using immunoassays and rotational thromboelastometry (ROTEM). Lung tissue was analyzed for complement and cytokines using qPCR and immunoassays. Results are presented as medians with interquartile range.ResultsIn 24 pigs receiving air infusion,...
The Journal of Immunology, 2021
Venous air embolism, which may complicate medical and surgical procedures, activates complement a... more Venous air embolism, which may complicate medical and surgical procedures, activates complement and triggers thromboinflammation. In lepirudin-anticoagulated human whole blood, we examined the effect of air bubbles on complement and its role in thromboinflammation. Whole blood from 16 donors was incubated with air bubbles without or with inhibitors of C3, C5, C5aR1, or CD14. Complement activation, hemostasis, and cytokine release were measured using ELISA and quantitative PCR. Compared with no air, incubating blood with air bubbles increased, on average, C3a 6.5-fold, C3bc 6-fold, C3bBbP 3.7-fold, C5a 4.6-fold, terminal complement complex sC5b9 3.6-fold, prothrombin fragments 1+2 (PTF1+2) 25-fold, tissue factor mRNA (TF-mRNA) 26-fold, microparticle tissue factor 6.1-fold, β-thromboglobulin 26-fold (all p < 0.05), and 25 cytokines 11-fold (range, 1.5–78-fold; all p < 0.0001). C3 inhibition attenuated complement and reduced PTF1+2 2-fold, TF-mRNA 5.4-fold, microparticle tissue f...
Journal of Clinical Apheresis, 2019
Introduction: Even if proprotein convertase subtilisin/kexin type 9 inhibitors have replaced lipo... more Introduction: Even if proprotein convertase subtilisin/kexin type 9 inhibitors have replaced lipoprotein apheresis in many patients, lipoprotein apheresis still is an important option in homozygous familial hypercholesterolemia, progressive atherosclerosis or when removal of lipoprotein(a) is indicated. Additional possible favorable effects beyond lipid lowering could include changes in the concentration of cytokines and improvement of hemorheology. Methods: We evaluated how whole blood adsorption, dextran sulfate plasma adsorption and double filtration plasmapheresis lipoprotein apheresis systems affected cytokine concentrations, using a human whole blood ex vivo model differentiating the effect of the lipoprotein apheresis and plasma separation columns and describing temporal changes. Results: Compared to the control bag, the whole blood adsorption system reduced IFN-γ, IL-8, IL-1ra, eotaxin, TNF, MCP-1, PDGF-BB, RANTES, MIP-1β and IP-10 (p<0.05). The dextran sulfate plasma adsorption system reduced IFN-γ, IL-8, IL-1ra, eotaxin, TNF, MCP-1, PDGF-BB, MIP-1β and IP10 (p<0.05). VEGF and GM-CSF were increased in the whole blood and dextran sulfate plasma adsorption systems (p <0.05). The double filtration plasmapheresis system reduced IFN-γ, IL-1ra, TNF, MIP-1β and IP-10 (p<0.05), while MCP-1,VEGF, GM-CSF and RANTES were increased (p <0.05). The plasma separation column increased concentration of RANTES, and was a barrier to reduction of eotaxin. Temporal patterns of concentration change indicated first pass increase of PDGF-BB and first pass reduction of IP-10. Conclusion: There were marked differences in how the three systems affected total and temporal cytokine concentration changes in this in vitro model, as well as compared to former in vivo studies.
Journal of Thrombosis and Haemostasis, 2018
coccus aureus-induced complement activation promotes tissue factor-mediated coagulation.
Molecular Immunology, 2017
treated ex vivo. Formation of TCC on other complement activating structures like monosodium urate... more treated ex vivo. Formation of TCC on other complement activating structures like monosodium urate crystals and zymosan was not affected by BCD. These data demonstrate that BCD inhibits CC-induced inflammatory responses, which may be explained by BCD-mediated attenuation of complement activation. Thus, these findings support the potential for using BCD in treatment of atherosclerosis.
Clinical and Experimental Immunology, 2018
SummaryThere is a close cross-talk between complement, Toll-like receptors (TLRs) and coagulation... more SummaryThere is a close cross-talk between complement, Toll-like receptors (TLRs) and coagulation. The role of the central complement component 5 (C5) in physiological and pathophysiological hemostasis has not, however, been fully elucidated. This study examined the effects of C5 in normal hemostasis and in Escherichia coli-induced coagulation and tissue factor (TF) up-regulation. Fresh whole blood obtained from six healthy donors and one C5-deficient individual (C5D) was anti-coagulated with the thrombin inhibitor lepirudin. Blood was incubated with or without E. coli in the presence of the C5 inhibitor eculizumab, a blocking anti-CD14 monoclonal antibody (anti-CD14) or the TLR-4 inhibitor eritoran. C5D blood was reconstituted with purified human C5. TF mRNA was measured by quantitative polymerase chain reaction (qPCR) and monocyte TF and CD11b surface expression by flow cytometry. Prothrombin fragment 1+2 (PTF1·2) in plasma and microparticles exposing TF (TF-MP) was measured by en...
Acta Anaesthesiologica Scandinavica, 2021
This is an open access article under the terms of the Creative Commons Attribution License, which... more This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Journal of Immunological Methods, 2020
The Complement System, 2021
Enzyme-linked immunosorbent assay (ELISA) enables fast and simple quantification of analytes in t... more Enzyme-linked immunosorbent assay (ELISA) enables fast and simple quantification of analytes in the pico- to nanogram range in complex samples. Here, we describe an ELISA for the detection of porcine C3a as a marker for complement activation. Antibody specificity is critical for a robust assay. This assay is based on a pair of antibodies specific for the porcine C3a molecule and thus does not react with native C3.
Shock, 2021
ABSTRACT Vitamin C combined with hydrocortisone is increasingly being used to treat septic patien... more ABSTRACT Vitamin C combined with hydrocortisone is increasingly being used to treat septic patients, even though this treatment regimen is based on questionable evidence. When used, a marked effect on key players of innate immunity would be expected, as sepsis is featured by a dysregulated immune response.Here, we explored the effect of vitamin C and hydrocortisone alone and combined, in an ex vivo human whole-blood model of Escherichia coli- or Staphylococcus aureus-induced inflammation. Inflammatory markers for activation of complement (TCC), granulocytes (myeloperoxidase), platelets (β-thromboglobulin), cytokines (TNF, IL-1β, IL6 and IL-8) and leukocytes (CD11b and oxidative burst) were quantified, by ELISA, multiplex technology and flow cytometry.In E. coli- and S. aureus-stimulated whole blood, a broad dose-titration of vitamin C and hydrocortisone alone did not lead to dose-response effects for the central innate immune mediators TCC and IL-6. Hence, the clinically relevant doses were used further. Compared to the untreated control sample, 2 of the 9 biomarkers induced by Escherichia coli were reduced by hydrocortisone and/or vitamin C. TNF was reduced by hydrocortisone alone (19%, p = 0.01) and by the combination (31%, p = 0.01). The oxidative burst of monocytes and granulocytes was reduced for both drugs alone and their combination, (ranging 8-19%, p < 0.05). Using Staphylococcus aureus, neither of the drugs, alone nor in combination, had any effects on the 9 biomarkers.In conclusion, despite the limitation of the ex vivo model, the effect of vitamin C and hydrocortisone on bacteria-induced inflammatory response in human whole blood is limited and following the clinical data.
Molecular Immunology, 2017
Immunobiology, Oct 1, 2016
Immunopharmacology, Aug 1, 2000
Apmis, Mar 25, 2018
Title: Granulocyte and monocyte CD11b expression during plasma separation is dependent on complem... more Title: Granulocyte and monocyte CD11b expression during plasma separation is dependent on complement factor 5 (C5)-an ex vivo study with blood from a C5 deficient individual. Running head: CD11b expression depends on C5.
Thrombosis and Haemostasis, 1999
Platelet compatibility after coating an artificial material with functionally active heparin was ... more Platelet compatibility after coating an artificial material with functionally active heparin was investigated. Blood was circulated in uncoated or heparin coated PVC tubing. In one hour platelet counts decreased from 155 (113-184)x10(9)/l to 124 (100-148)x10(9)/l with uncoated compared to 164 (132-192)x10(9)/l with heparin coated tubing (intergroup p = 0.02). Beta-thromboglobulin increased from 116 (80-148) microg/l to 1039 (757-1298) microg/l with uncoated and to 352 (229-638) microg/l with heparin coated tubing (intergroup p = 0.005). Platelet counts and beta-thromboglobulin correlated closely with complement activation. Solid-phase enzyme immunoassay demonstrated substantial deposition of CD42a/GPIbIX and CD61/GPIIIa on uncoated, but not on heparin coated tubing (intergroup p<0.0005). Scanning electron microscopy demonstrated activated platelets and aggregates on uncoated in contrast to heparin coated tubing, where scattered, unactivated platelets were found. Changes in P-selectin and microparticles were minor. In conclusion, this heparin surface substantially improved platelet compatibility. Markers of choice for in vitro evaluation were platelet counts, beta-thromboglobulin and platelet deposition.
Proceedings of the National Academy of Sciences of the United States of America, Sep 15, 2009
Complement component C5 is crucial for experimental animal inflammatory tissue damage; however, i... more Complement component C5 is crucial for experimental animal inflammatory tissue damage; however, its involvement in human inflammation is incompletely understood. The responses to Gram-negative bacteria were here studied taking advantage of human genetic complement-deficiencies-nature's own knockouts-including a previously undescribed C5 defect. Such deficiencies provide a unique tool for investigating the biological role of proteins. The experimental conditions allowed cross-talk between the different inflammatory pathways using a whole blood model based on the anticoagulant lepirudin, which does not interfere with the complement system. Expression of tissue factor, cell adhesion molecules, and oxidative burst depended highly on C5, mediated through the activation product C5a, whereas granulocyte enzyme release relied mainly on C3 and was C5a-independent. Release of cytokines and chemokines was mediated to varying degrees by complement and CD14; for example, interleukin (IL)-1 and IL-8 were more dependent on complement than IFN-␥ and IL-6, which were highly dependent on CD14. IL-1 receptor antagonist (IL-1ra) and IFN-␥ inducible protein 10 (IP-10) were fully dependent on CD14 and inversely regulated by complement, that is, complement deficiency and complement inhibition enhanced their release. Granulocyte responses were mainly complement-dependent, whereas monocyte responses were more dependent on CD14. Notably, all responses were abolished by combined neutralization of complement and CD14. The present study provides important insight into the comprehensive role of complement in human inflammatory responses to Gram-negative bacteria.
Immunobiology, Nov 1, 2012
, CFHR5) are also reported in MPGN II patients. Here we report two related MPGN II patients, who ... more , CFHR5) are also reported in MPGN II patients. Here we report two related MPGN II patients, who present decreased C3 plasma level and increased Ba values in the early stages of disease, but lack C3 nephritic factor (C3 Nef), factor H, C3b and factor B autoantibodies. Multiplex ligation dependent probe amplification (MLPA) identified a heterozygous chromosomal deletion of exons IV and V in the CFHR2 gene. In addition, the chromosomal breakpoint in CFHR2 intron III and deletion of a 5.3 kb genomic segment spanning from the CFHR2 to CFHR5 was identified by inverse-nested PCR. Rearrangement of CFHR2/CFHR5 region results in expression of a novel 65-70 kDa protein doublet secreted in plasma which represents differently glycosylated forms of a hybrid protein, including SCRs 1-2 of CFHR2 and all 9 SCRs of CFHR5. To address the function of the novel hybrid protein a recombinant hybrid rCFHR21-2-CFHR5 was expressed and the mutant protein was purified from plasma of the two patients. rCFHR21-2-CFHR5 bound to C3 and C3 activation fragments, caused deregulation of the C3 convertase and enhanced enzyme activity in form of C3a generation. Moreover, rCFHR21-2-CFHR5 stimulated AP in normal human serum and caused C3b accumulation on surfaces. In conclusion, we define a new genetic cause for MPGN II/DDD based on a chromosomal deletion in the CFHR gene cluster and expression of a CFHR2/CFHR5 gene protein. Defective AP regulation by the hybrid protein apparently explains deposition of C3 fragments at the GBM and consequently development of MPGN II. This defective regulation by the new hybrid protein provides fundamental insights into the pathomechanism of MPGN II and is relevant to define the appropriate therapy for the patients.
The Journal of Immunology
The complement system is an intricate cascade of the innate immune system and plays a key role in... more The complement system is an intricate cascade of the innate immune system and plays a key role in microbial defense, inflammation, organ development, and tissue regeneration. There is increasing interest in developing complement regulatory and inhibitory agents to treat complement dysfunction. In this study, we describe the nanobody hC3Nb3, which is specific for the C-terminal C345c domain of human and mouse complement component C3/C3b/C3c and potently inhibits C3 cleavage by the alternative pathway. A high-resolution structure of the hC3Nb3–C345c complex explains how the nanobody blocks proconvertase assembly. Surprisingly, although the nanobody does not affect classical pathway–mediated C3 cleavage, hC3Nb3 inhibits classical pathway–driven hemolysis, suggesting that the C-terminal domain of C3b has an important function in classical pathway C5 convertase activity. The hC3Nb3 nanobody binds C3 with low nanomolar affinity in an SDS-resistant complex, and the nanobody is demonstrated...
Molecular Immunology, Oct 1, 2008
Human astroviruses (HAstVs) constitute a family of nonenveloped, RNA viruses that cause non-infla... more Human astroviruses (HAstVs) constitute a family of nonenveloped, RNA viruses that cause non-inflammatory gastroenteritis, predominantly in infants. While HAstVs represent a significant public health concern, very little is known about the host immune response to these viruses. The HAstV capsid is initially assembled from multiple copies of the coat protein (CP) precursor and we have previously demonstrated that purified HAstV CP specifically binds to C1q resulting in inhibition of classical pathway activity. To further analyze the precise mechanism of inhibition, we examined the suppression of C1 activity by CP. CP was found to inhibit the activation of C1s and downstream complement activation (C5a) in the presence of heat-aggregated IgG, a potent classical pathway activator. CP dose-dependently bound to C1q, the isolated globular heads and the collagen-like regions of the C1q molecule and formed complexes with C1q in solution. Given the structural and functional relatedness of C1q and MBL, we subsequently investigated the interactions between CP and MBL. CP bound to purified MBL and was able to inhibit mannan-mediated activation of the lectin pathway as well. Finally, given the evolutionarily conserved nature of mammalian complement factors, we investigated whether CP was able to cross the species barrier and inhibit complement activation in rodent serum. CP inhibited complement activation in rat serum demonstrating dose-dependent inhibition of C3 activation and MAC formation. Together, our data demonstrates that HAstV CP is a novel complement inhibitor that binds C1q and MBL to suppress activation of both the classical and lectin pathways of complement.
Frontiers in Immunology, 2022
IntroductionAir embolism may complicate invasive medical procedures. Bubbles trigger complement C... more IntroductionAir embolism may complicate invasive medical procedures. Bubbles trigger complement C3-mediated cytokine release, coagulation, and platelet activationin vitroin human whole blood. Since these findings have not been verifiedin vivo, we aimed to examine the effects of air embolism in pigs on thromboinflammation.MethodsForty-five landrace pigs, average 17 kg (range 8.5-30), underwent intravenous air infusion for 300 or 360 minutes (n=29) or served as sham (n=14). Fourteen pigs were excluded due to e.g. infections or persistent foramen ovale. Blood was analyzed for white blood cells (WBC), complement activation (C3a and terminal C5b-9 complement complex [TCC]), cytokines, and hemostatic parameters including thrombin-antithrombin (TAT) using immunoassays and rotational thromboelastometry (ROTEM). Lung tissue was analyzed for complement and cytokines using qPCR and immunoassays. Results are presented as medians with interquartile range.ResultsIn 24 pigs receiving air infusion,...
The Journal of Immunology, 2021
Venous air embolism, which may complicate medical and surgical procedures, activates complement a... more Venous air embolism, which may complicate medical and surgical procedures, activates complement and triggers thromboinflammation. In lepirudin-anticoagulated human whole blood, we examined the effect of air bubbles on complement and its role in thromboinflammation. Whole blood from 16 donors was incubated with air bubbles without or with inhibitors of C3, C5, C5aR1, or CD14. Complement activation, hemostasis, and cytokine release were measured using ELISA and quantitative PCR. Compared with no air, incubating blood with air bubbles increased, on average, C3a 6.5-fold, C3bc 6-fold, C3bBbP 3.7-fold, C5a 4.6-fold, terminal complement complex sC5b9 3.6-fold, prothrombin fragments 1+2 (PTF1+2) 25-fold, tissue factor mRNA (TF-mRNA) 26-fold, microparticle tissue factor 6.1-fold, β-thromboglobulin 26-fold (all p < 0.05), and 25 cytokines 11-fold (range, 1.5–78-fold; all p < 0.0001). C3 inhibition attenuated complement and reduced PTF1+2 2-fold, TF-mRNA 5.4-fold, microparticle tissue f...
Journal of Clinical Apheresis, 2019
Introduction: Even if proprotein convertase subtilisin/kexin type 9 inhibitors have replaced lipo... more Introduction: Even if proprotein convertase subtilisin/kexin type 9 inhibitors have replaced lipoprotein apheresis in many patients, lipoprotein apheresis still is an important option in homozygous familial hypercholesterolemia, progressive atherosclerosis or when removal of lipoprotein(a) is indicated. Additional possible favorable effects beyond lipid lowering could include changes in the concentration of cytokines and improvement of hemorheology. Methods: We evaluated how whole blood adsorption, dextran sulfate plasma adsorption and double filtration plasmapheresis lipoprotein apheresis systems affected cytokine concentrations, using a human whole blood ex vivo model differentiating the effect of the lipoprotein apheresis and plasma separation columns and describing temporal changes. Results: Compared to the control bag, the whole blood adsorption system reduced IFN-γ, IL-8, IL-1ra, eotaxin, TNF, MCP-1, PDGF-BB, RANTES, MIP-1β and IP-10 (p<0.05). The dextran sulfate plasma adsorption system reduced IFN-γ, IL-8, IL-1ra, eotaxin, TNF, MCP-1, PDGF-BB, MIP-1β and IP10 (p<0.05). VEGF and GM-CSF were increased in the whole blood and dextran sulfate plasma adsorption systems (p <0.05). The double filtration plasmapheresis system reduced IFN-γ, IL-1ra, TNF, MIP-1β and IP-10 (p<0.05), while MCP-1,VEGF, GM-CSF and RANTES were increased (p <0.05). The plasma separation column increased concentration of RANTES, and was a barrier to reduction of eotaxin. Temporal patterns of concentration change indicated first pass increase of PDGF-BB and first pass reduction of IP-10. Conclusion: There were marked differences in how the three systems affected total and temporal cytokine concentration changes in this in vitro model, as well as compared to former in vivo studies.
Journal of Thrombosis and Haemostasis, 2018
coccus aureus-induced complement activation promotes tissue factor-mediated coagulation.
Molecular Immunology, 2017
treated ex vivo. Formation of TCC on other complement activating structures like monosodium urate... more treated ex vivo. Formation of TCC on other complement activating structures like monosodium urate crystals and zymosan was not affected by BCD. These data demonstrate that BCD inhibits CC-induced inflammatory responses, which may be explained by BCD-mediated attenuation of complement activation. Thus, these findings support the potential for using BCD in treatment of atherosclerosis.
Clinical and Experimental Immunology, 2018
SummaryThere is a close cross-talk between complement, Toll-like receptors (TLRs) and coagulation... more SummaryThere is a close cross-talk between complement, Toll-like receptors (TLRs) and coagulation. The role of the central complement component 5 (C5) in physiological and pathophysiological hemostasis has not, however, been fully elucidated. This study examined the effects of C5 in normal hemostasis and in Escherichia coli-induced coagulation and tissue factor (TF) up-regulation. Fresh whole blood obtained from six healthy donors and one C5-deficient individual (C5D) was anti-coagulated with the thrombin inhibitor lepirudin. Blood was incubated with or without E. coli in the presence of the C5 inhibitor eculizumab, a blocking anti-CD14 monoclonal antibody (anti-CD14) or the TLR-4 inhibitor eritoran. C5D blood was reconstituted with purified human C5. TF mRNA was measured by quantitative polymerase chain reaction (qPCR) and monocyte TF and CD11b surface expression by flow cytometry. Prothrombin fragment 1+2 (PTF1·2) in plasma and microparticles exposing TF (TF-MP) was measured by en...
Acta Anaesthesiologica Scandinavica, 2021
This is an open access article under the terms of the Creative Commons Attribution License, which... more This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Journal of Immunological Methods, 2020
The Complement System, 2021
Enzyme-linked immunosorbent assay (ELISA) enables fast and simple quantification of analytes in t... more Enzyme-linked immunosorbent assay (ELISA) enables fast and simple quantification of analytes in the pico- to nanogram range in complex samples. Here, we describe an ELISA for the detection of porcine C3a as a marker for complement activation. Antibody specificity is critical for a robust assay. This assay is based on a pair of antibodies specific for the porcine C3a molecule and thus does not react with native C3.
Shock, 2021
ABSTRACT Vitamin C combined with hydrocortisone is increasingly being used to treat septic patien... more ABSTRACT Vitamin C combined with hydrocortisone is increasingly being used to treat septic patients, even though this treatment regimen is based on questionable evidence. When used, a marked effect on key players of innate immunity would be expected, as sepsis is featured by a dysregulated immune response.Here, we explored the effect of vitamin C and hydrocortisone alone and combined, in an ex vivo human whole-blood model of Escherichia coli- or Staphylococcus aureus-induced inflammation. Inflammatory markers for activation of complement (TCC), granulocytes (myeloperoxidase), platelets (β-thromboglobulin), cytokines (TNF, IL-1β, IL6 and IL-8) and leukocytes (CD11b and oxidative burst) were quantified, by ELISA, multiplex technology and flow cytometry.In E. coli- and S. aureus-stimulated whole blood, a broad dose-titration of vitamin C and hydrocortisone alone did not lead to dose-response effects for the central innate immune mediators TCC and IL-6. Hence, the clinically relevant doses were used further. Compared to the untreated control sample, 2 of the 9 biomarkers induced by Escherichia coli were reduced by hydrocortisone and/or vitamin C. TNF was reduced by hydrocortisone alone (19%, p = 0.01) and by the combination (31%, p = 0.01). The oxidative burst of monocytes and granulocytes was reduced for both drugs alone and their combination, (ranging 8-19%, p < 0.05). Using Staphylococcus aureus, neither of the drugs, alone nor in combination, had any effects on the 9 biomarkers.In conclusion, despite the limitation of the ex vivo model, the effect of vitamin C and hydrocortisone on bacteria-induced inflammatory response in human whole blood is limited and following the clinical data.
Molecular Immunology, 2017