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2.
Blood ; 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31971571

RESUMO

Storage lesion-induced red cell-derived microvesicles (RBC-MVs) propagate coagulation by supporting the assembly of the prothrombinase complex. It has also been reported that RBC-MVs initiate coagulation via the intrinsic pathway. To elucidate the mechanism(s) of RBC-MV-induced coagulation activation, the ability of storage lesion-induced RBC-MVs to activate each zymogen of the intrinsic pathway was assessed in a buffer system. Simultaneously, the thrombin generation (TG) assay was used to assess their ability to initiate coagulation in plasma. RBC-MVs directly activated factor XII (FXII) or prekallikrein, but not FXI or FIX. RBC-MVs initiated TG in normal pooled plasma and in FXII-deficient or FXI-deficient, but not in FIX-deficient plasma, suggesting an alternate pathway that bypasses both FXII and FXI. Interestingly, RBC-MVs generated FIXa in a prekallikrein-dependent manner. Similarly, purified kallikrein activated FIX in buffer and initiated TG in normal pooled plasma, as well as FXII-deficient or FXI-deficient, but not FIX-deficient plasma. Dual inhibition of FXIIa by corn trypsin inhibitor and kallikrein by soybean trypsin inhibitor was required to abolish RBC-MV-induced TG in normal pooled plasma, whereas kallikrein inhibition alone was sufficient to abolish TG in FXII-deficient or FXI-deficient plasma. Heating RBC-MVs at 60°C for 15 minutes or pre-treatment with trypsin abolished TG, suggesting the presence of microvesicle-associated protein(s) that is(are) required for contact activation. In summary, RBC-MVs activate both FXII and prekallikrein, leading to FIX activation by two independent pathways, namely the classical FXIIa-FXI-FIX pathway and via direct kallikrein activation of FIX. These data suggest novel mechanisms by which RBC transfusion mediates inflammatory and/or thrombotic outcomes.

3.
Cell Rep ; 29(6): 1690-1706.e4, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31693905

RESUMO

Changes in the endothelium of the cerebral vasculature can contribute to inflammatory, thrombotic, and malignant disorders. The importance of defining cell-type-specific genes and their modification in disease is increasingly recognized. Here, we develop a bioinformatics-based approach to identify normal brain cell-enriched genes, using bulk RNA sequencing (RNA-seq) data from 238 normal human cortex samples from 2 independent cohorts. We compare endothelial cell-enriched gene profiles with astrocyte, oligodendrocyte, neuron, and microglial cell profiles. Endothelial changes in malignant disease are explored using RNA-seq data from 516 lower-grade gliomas and 401 glioblastomas. Lower-grade gliomas appear to be an "endothelial intermediate" between normal brain and glioblastoma. We apply our method for the prediction of glioblastoma-specific endothelial biomarkers, providing potential diagnostic or therapeutic targets. In summary, we provide a roadmap of endothelial cell identity in normal and malignant brain, using a method developed to resolve bulk RNA-seq into constituent cell-type-enriched profiles.

4.
Front Immunol ; 10: 2011, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507606

RESUMO

Factor XII (FXII) is the zymogen of serine protease, factor XIIa (FXIIa). FXIIa enzymatic activities have been extensively studied and FXIIa inhibition is emerging as a promising target to treat or prevent thrombosis without creating a hemostatic defect. FXII and plasma prekallikrein reciprocally activate each other and result in liberation of bradykinin. Due to its unique structure among coagulation factors, FXII exerts mitogenic activity in endothelial and smooth muscle cells, indicating that zymogen FXII has activities independent of its protease function. A growing body of evidence has revealed that both FXII and FXIIa upregulate neutrophil functions, contribute to macrophage polarization and induce T-cell differentiation. In vivo, these signaling activities contribute to host defense against pathogens, mediate the development of neuroinflammation, influence wound repair and may facilitate cancer maintenance and progression. Here, we review the roles of FXII in innate immunity as they relate to non-sterile and sterile immune responses.

6.
J Thromb Haemost ; 17(11): 1848-1859, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31400072

RESUMO

BACKGROUND: Laboratory analyses of blood samples are essential for diagnostics and therapy monitoring of patients with bleeding and thromboembolic diseases. Following publication of the core curriculum for clinical thrombosis and hemostasis, the International Society on Thrombosis and Haemostasis (ISTH) recognized that thrombosis and hemostasis laboratory specialists require distinct competencies that differ from medical doctors working clinically with patients. To address this gap the ISTH formed a working group of international hemostasis and thrombosis laboratory specialists to develop an evidence-based core curriculum for laboratory specialists. OBJECTIVE: This research sought consensus from the international community on core competencies required for laboratory specialists in thrombosis and hemostasis. METHODS: A draft list of 64 competencies was developed and an online stakeholder survey was circulated electronically to 15 302 ISTH members and contacts in the wider international community. The results were analyzed and used to develop the final approved core curriculum. RESULTS: Three hundred and thirty responses contained meaningful data, with broad international representation of specialists. No draft competencies were excluded, and 58 were rated as "does" or "shows how." The Leik measure of consensus for most competences was "moderate" (n = 30) or "fair" (n = 32). CONCLUSIONS: The development of an international core curriculum for laboratory specialists provides a foundation for the development and enhancement of education and quality management of the laboratory. Although there is no formal designation for laboratory specialists, international governing bodies and regulatory organizations are encouraged to consider the diagnostic core curriculum for development and accreditation of more standardized educational programs and formal assessment across jurisdictions.

7.
Blood ; 134(19): 1658-1669, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31366623

RESUMO

The contact system produces the inflammatory peptide bradykinin and contributes to experimental thrombosis. C1 esterase-inhibitor (C1INH) deficiency or gain-of-function mutations in factor XII (FXII) cause hereditary angioedema, a life-threatening tissue swelling disease. C1INH is a relatively weak contact system enzyme inhibitor. Although α1-antitrypsin (α1AT) does not naturally inhibit contact system enzymes, a human mutation (M358R; α1AT-Pittsburgh) changes it into a powerful broad-spectrum enzyme inhibitor. It blocks the contact system, but also thrombin and activated protein C (APC), making it an unattractive candidate for therapeutic contact system blockade. We adapted the reactive center loop of α1AT-Pittsburgh (AIPR/S) to overcome these obstacles. Two α1AT variants (SMTR/S and SLLR/S) strongly inhibit plasma kallikrein, activated FXII, and plasmin. α1AT-SMTR/S no longer inhibits thrombin, but residually inhibits APC. In contrast, α1AT-SLLR/S residually inhibits thrombin, but no longer APC. Additional modification at the P1' position (S→V) eliminates residual inhibition of thrombin and APC for both variants, while retaining their properties as contact system inhibitors. Both α1AT-SMTR/V and -SLLR/V are superior to C1INH in reducing bradykinin production in plasma. Owing to their capacity to selectively block contact system-driven coagulation, both variants block vascular occlusion in an in vivo model for arterial thrombosis. Furthermore, both variants block acute carrageenan-induced tissue edema in mice. Finally, α1AT-SLLR/V, our most powerful candidate, suppresses epithelial leakage of the gut in a mouse model of colitis. Our findings confirm that redesign of α1AT strongly alters its inhibitory behavior and can be used for the treatment of contact system-mediated thrombosis and inflammation.

8.
N Engl J Med ; 380(26): 2529-2540, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31242362

RESUMO

BACKGROUND: Data regarding high-sensitivity troponin concentrations in patients presenting to the emergency department with symptoms suggestive of myocardial infarction may be useful in determining the probability of myocardial infarction and subsequent 30-day outcomes. METHODS: In 15 international cohorts of patients presenting to the emergency department with symptoms suggestive of myocardial infarction, we determined the concentrations of high-sensitivity troponin I or high-sensitivity troponin T at presentation and after early or late serial sampling. The diagnostic and prognostic performance of multiple high-sensitivity troponin cutoff combinations was assessed with the use of a derivation-validation design. A risk-assessment tool that was based on these data was developed to estimate the risk of index myocardial infarction and of subsequent myocardial infarction or death at 30 days. RESULTS: Among 22,651 patients (9604 in the derivation data set and 13,047 in the validation data set), the prevalence of myocardial infarction was 15.3%. Lower high-sensitivity troponin concentrations at presentation and smaller absolute changes during serial sampling were associated with a lower likelihood of myocardial infarction and a lower short-term risk of cardiovascular events. For example, high-sensitivity troponin I concentrations of less than 6 ng per liter and an absolute change of less than 4 ng per liter after 45 to 120 minutes (early serial sampling) resulted in a negative predictive value of 99.5% for myocardial infarction, with an associated 30-day risk of subsequent myocardial infarction or death of 0.2%; a total of 56.5% of the patients would be classified as being at low risk. These findings were confirmed in an external validation data set. CONCLUSIONS: A risk-assessment tool, which we developed to integrate the high-sensitivity troponin I or troponin T concentration at emergency department presentation, its dynamic change during serial sampling, and the time between the obtaining of samples, was used to estimate the probability of myocardial infarction on emergency department presentation and 30-day outcomes. (Funded by the German Center for Cardiovascular Research [DZHK]; ClinicalTrials.gov numbers, NCT00470587, NCT02355457, NCT01852123, NCT01994577, and NCT03227159; and Australian New Zealand Clinical Trials Registry numbers, ACTRN12611001069943, ACTRN12610000766011, ACTRN12613000745741, and ACTRN12611000206921.).


Assuntos
Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Medição de Risco/métodos , Troponina/sangue , Adulto , Idoso , Biomarcadores/sangue , Estudos de Coortes , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Sensibilidade e Especificidade , Troponina I/sangue
9.
Front Med (Lausanne) ; 6: 76, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31106204

RESUMO

Activated platelets and mast cells expose the inorganic polymer, polyphosphate (polyP) on their surfaces. PolyP initiates procoagulant and proinflammatory reactions and the polymer has been recognized as a therapeutic target for interference with blood coagulation and vascular hyperpermeability. PolyP content and chain length depend on the specific cell type and energy status, which may affect cellular functions. PolyP metabolism has mainly been studied in bacteria and yeast, but its roles in eukaryotic cells and mammalian systems have remained enigmatic. In this review, we will present an overview of polyP functions, focusing on intra- and extracellular roles of the polymer and discuss open questions that emerge from the current knowledge on polyP regulation.

10.
Blood ; 133(19): 2090-2099, 2019 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-30898865

RESUMO

Tissue factor, coagulation factor XII, platelets, and neutrophils are implicated as important players in the pathophysiology of (experimental) venous thrombosis (VT). Their role became evident in mouse models in which surgical handlings were required to provoke VT. Combined inhibition of the natural anticoagulants antithrombin (Serpinc1) and protein C (Proc) using small interfering RNA without additional triggers also results in a venous thrombotic phenotype in mice, most notably with vessel occlusion in large veins of the head. VT is fatal but is fully rescued by thrombin inhibition. In the present study, we used this VT mouse model to investigate the involvement of tissue factor, coagulation factor XII, platelets, and neutrophils. Antibody-mediated inhibition of tissue factor reduced the clinical features of VT, the coagulopathy in the head, and fibrin deposition in the liver. In contrast, genetic deficiency in, and small interfering RNA-mediated depletion of, coagulation factor XII did not alter VT onset, severity, or thrombus morphology. Antibody-mediated depletion of platelets fully abrogated coagulopathy in the head and liver fibrin deposition. Although neutrophils were abundant in thrombotic lesions, depletion of circulating Ly6G-positive neutrophils did not affect onset, severity, thrombus morphology, or liver fibrin deposition. In conclusion, VT after inhibition of antithrombin and protein C is dependent on the presence of tissue factor and platelets but not on coagulation factor XII and circulating neutrophils. This study shows that distinct procoagulant pathways operate in mouse VT, dependent on the triggering stimulus.


Assuntos
Plaquetas/metabolismo , Fator XII/metabolismo , Neutrófilos/metabolismo , Tromboplastina/metabolismo , Trombose Venosa/sangue , Animais , Antitrombina III/antagonistas & inibidores , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Proteína C/antagonistas & inibidores
11.
FASEB J ; 33(2): 2599-2609, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30281335

RESUMO

Neutrophil recruitment and plasma exudation are key elements in the immune response to injury or infection. Activated neutrophils stimulate opening of the endothelial barrier; however, the underlying mechanisms have remained largely unknown. In this study, we identified a pivotal role of the proinflammatory kallikrein-kinin system and consequent formation of bradykinin in neutrophil-evoked vascular leak. In mouse and hamster models of acute inflammation, inhibitors of bradykinin generation, and signaling markedly reduced plasma exudation in response to chemoattractant activation of neutrophils. The neutrophil-driven leak was likewise suppressed in mice deficient in either the bradykinin B2 receptor or factor XII (initiator of the kallikrein-kinin system). In human endothelial cell monolayers, material secreted from activated neutrophils induced cytoskeletal rearrangement, leading to paracellular gap formation in a bradykinin-dependent manner. As a mechanistic basis, we found that a neutrophil-derived heparin-binding protein (HBP/azurocidin) displaced the bradykinin precursor high-molecular-weight kininogen from endothelial cells, thereby enabling proteolytic processing of kininogen into bradykinin by neutrophil and plasma proteases. These data provide novel insight into the signaling pathway by which neutrophils open up the endothelial barrier and identify the kallikrein-kinin system as a target for therapeutic interventions in acute inflammatory reactions.-Kenne, E., Rasmuson, J., Renné, T., Vieira, M. L., Müller-Esterl, W., Herwald, H., Lindbom, L. Neutrophils engage the kallikrein-kinin system to open up the endothelial barrier in acute inflammation.


Assuntos
Permeabilidade da Membrana Celular , Endotélio Vascular/fisiologia , Inflamação/patologia , Sistema Calicreína-Cinina/fisiologia , Neutrófilos/metabolismo , Edema Pulmonar/patologia , Animais , Bradicinina/metabolismo , Endotélio Vascular/citologia , Fator XII/metabolismo , Feminino , Humanos , Inflamação/metabolismo , Cininogênio de Alto Peso Molecular/metabolismo , Masculino , Mesocricetus , Camundongos , Camundongos Endogâmicos C57BL , Infiltração de Neutrófilos , Edema Pulmonar/etiologia , Edema Pulmonar/metabolismo
12.
FASEB J ; 33(2): p. 2599-2609, 2019.
Artigo | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib15819

RESUMO

Neutrophil recruitment and plasma exudation are key elements in the immune response to injury or infection. Activated neutrophils stimulate opening of the endothelial barrier; however, the underlying mechanisms have remained largely unknown. In this study, we identified a pivotal role of the proinflammatory kallikrein-kinin system and consequent formation of bradykinin in neutrophil-evoked vascular leak. In mouse and hamster models of acute inflammation, inhibitors of bradykinin generation, and signaling markedly reduced plasma exudation in response to chemoattractant activation of neutrophils. The neutrophil-driven leak was likewise suppressed in mice deficient in either the bradykinin B-2 receptor or factor XII (initiator of the kallikrein-kinin system). In human endothelial cell monolayers, material secreted from activated neutrophils induced cytoskeletal rearrangement, leading to paracellular gap formation in a bradykinin-dependent manner. As a mechanistic basis, we found that a neutrophil-derived heparin-binding protein (HBP/azurocidin) displaced the bradykinin precursor high-molecular-weight kininogen from endothelial cells, thereby enabling proteolytic processing of kininogen into bradykinin by neutrophil and plasma proteases. These data provide novel insight into the signaling pathway by which neutrophils open up the endothelial barrier and identify the kallikrein-kinin system as a target for therapeutic interventions in acute inflammatory reactions.Kenne, E., Rasmuson, J., Renne, T., Vieira, M. L., Muller-Esterl, W., Herwald, H., Lindbom, L. Neutrophils engage the kallikrein-kinin system to open up the endothelial barrier in acute inflammation.

13.
Sci Rep ; 8(1): 14668, 2018 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-30279450

RESUMO

The intermediate filament protein nestin is expressed during embryonic development, but considered largely restricted to areas of regeneration in the adult. Here, we perform a body-wide transcriptome and protein-profiling analysis to reveal that nestin is constitutively, and highly-selectively, expressed in adult human endothelial cells (EC), independent of proliferative status. Correspondingly, we demonstrate that it is not a marker for tumour EC in multiple malignancy types. Imaging of EC from different vascular beds reveals nestin subcellular distribution is shear-modulated. siRNA inhibition of nestin increases EC proliferation, and nestin expression is reduced in atherosclerotic plaque neovessels. eQTL analysis reveals an association between SNPs linked to cardiovascular disease and reduced aortic EC nestin mRNA expression. Our study challenges the dogma that nestin is a marker of proliferation, and provides insight into its regulation and function in EC. Furthermore, our systems-based approach can be applied to investigate body-wide expression profiles of any candidate protein.


Assuntos
Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Nestina/fisiologia , Biologia de Sistemas/métodos , Adulto , Aorta/citologia , Aorta/patologia , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/patologia , Movimento Celular , Proliferação de Células , Células Cultivadas , Bases de Dados Genéticas/estatística & dados numéricos , Conjuntos de Dados como Assunto , Endotélio Vascular/citologia , Endotélio Vascular/patologia , Feminino , Perfilação da Expressão Gênica/métodos , Haplótipos , Humanos , Masculino , Neoplasias/patologia , Neovascularização Patológica/patologia , Polimorfismo de Nucleotídeo Único , Cultura Primária de Células , Proteômica/métodos , Locos de Características Quantitativas , RNA Interferente Pequeno/metabolismo , Análise Serial de Tecidos/métodos
14.
J Immunol ; 201(10): 3106-3118, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30355783

RESUMO

A disintegrin and metalloproteinase (ADAM) 17 has been implicated in many shedding processes. Major substrates of ADAM17 are TNF-α, IL-6R, and ligands of the epidermal growth factor receptor. The essential role of the protease is emphasized by the fact that ADAM17 deficiency is lethal in mice. To study ADAM17 function in vivo, we generated viable hypomorphic ADAM17 mice called ADAM17ex/ex mice. Recent studies indicated regulation of proteolytic ADAM17 activity by cellular processes such as cytoplasmic phosphorylation and removal of the prodomain by furin cleavage. Maturation and thus activation of ADAM17 is not fully understood. So far, studies of ADAM17 maturation have been mainly limited to mouse embryonic fibroblasts or transfected cell lines relying on nonphysiologic stimuli such as phorbol esters, thus making interpretation of the results difficult in a physiologic context. In this article, we present a robust cell system to study ADAM17 maturation and function in primary cells of the immune system. To this end, HoxB8 conditionally immortalized macrophage precursor cell lines were derived from bone marrow of wild-type and hypomorphic ADAM17ex/ex mice, which are devoid of measurable ADAM17 activity. ADAM17 mutants were stably expressed in macrophage precursor cells, differentiated to macrophages under different growth factor conditions (M-CSF versus GM-CSF), and analyzed for cellular localization, proteolytic activity, and podosome disassembly. Our study reveals maturation and activity of ADAM17 in a more physiological-immune cell system. We show that this cell system can be further exploited for genetic modifications of ADAM17 and for studying its function in immune cells.


Assuntos
Proteína ADAM17/química , Proteína ADAM17/metabolismo , Técnicas de Cultura de Células/métodos , Células Dendríticas/enzimologia , Macrófagos/enzimologia , Animais , Linhagem Celular , Proteínas de Homeodomínio , Camundongos
15.
Sci Rep ; 8(1): 14823, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30287927

RESUMO

Mouse models are important and versatile tools to study mechanisms and novel therapies of human disease in vivo. Both, the number and the complexity of murine models are constantly increasing and modification of genes of interest as well as any exogenous challenge may lead to unanticipated biological effects. Laboratory diagnostics of blood samples provide a comprehensive and rapid screening for multiple organ function and are fundamental to detect human disease. Here, we adapt an array of laboratory medicine-based tests commonly used in humans to establish a platform for standardized, multi-parametric, and quality-controlled diagnostics of murine blood samples. We determined sex-dependent reference intervals of 51 commonly used laboratory medicine tests for samples obtained from the C57BL/6J mouse strain. As a proof of principle, we applied these diagnostic tests in a mouse cytomegalovirus (MCMV) infection model to screen for organ damage. Consistent with histopathological findings, plasma concentrations of liver-specific enzymes were elevated, supporting the diagnosis of a virus-induced hepatitis. Plasma activities of aminotransferases correlated with viral loads in livers at various days after MCMV infection and discriminated infected from non-infected animals. This study provides murine blood reference intervals of common laboratory medicine parameters and illustrates the use of these tests for diagnosis of infectious disease in experimental animals.


Assuntos
Análise Química do Sangue/métodos , DNA Viral/sangue , Testes Diagnósticos de Rotina/métodos , Hepatite Viral Animal/diagnóstico , Infecções por Herpesviridae/veterinária , Muromegalovirus/isolamento & purificação , Doenças dos Roedores/diagnóstico , Animais , Hepatite Viral Animal/virologia , Infecções por Herpesviridae/diagnóstico , Infecções por Herpesviridae/virologia , Testes de Função Hepática , Camundongos Endogâmicos C57BL , Doenças dos Roedores/virologia , Transaminases/sangue
16.
Nat Microbiol ; 3(10): 1161-1174, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30202017

RESUMO

Congenital Zika virus (ZIKV) syndrome may cause fetal microcephaly in ~1% of affected newborns. Here, we investigate whether the majority of clinically inapparent newborns might suffer from long-term health impairments not readily visible at birth. Infection of immunocompetent pregnant mice with high-dose ZIKV caused severe offspring phenotypes, such as fetal death, as expected. By contrast, low-dose (LD) maternal ZIKV infection resulted in reduced fetal birth weight but no other obvious phenotypes. Male offspring born to LD ZIKV-infected mothers had increased testosterone (TST) levels and were less likely to survive in utero infection compared to their female littermates. Males also presented an increased number of immature neurons in apical and basal hippocampal dendrites, while female offspring had immature neurons in basal dendrites only. Moreover, male offspring with high but not very high (storm) TST levels were more likely to suffer from learning and memory impairments compared to females. Future studies are required to understand the impact of TST on neuropathological and neurocognitive impairments in later life. In summary, increased sex-specific vigilance is required in countries with high ZIKV prevalence, where impaired neurodevelopment may be camouflaged by a healthy appearance at birth.


Assuntos
Transtornos Neurocognitivos/etiologia , Complicações Infecciosas na Gravidez , Infecção por Zika virus/complicações , Zika virus , Animais , Animais Recém-Nascidos , Encéfalo/patologia , Modelos Animais de Doenças , Feminino , Humanos , Transmissão Vertical de Doença Infecciosa , Masculino , Transtornos Neurocognitivos/patologia , Transtornos Neurocognitivos/fisiopatologia , Insuficiência Placentária , Gravidez , Fatores Sexuais , Testosterona/sangue , Infecção por Zika virus/transmissão
17.
J Reprod Immunol ; 128: 30-37, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29886307

RESUMO

During pregnancy the maternal immune system has to develop tolerance towards the developing fetus. These changes in maternal immunity can result in increased severity of certain infections, but also in amelioration of autoimmune diseases. Pregnancy-related hormones have been suggested to play a central role in the adaptation of the maternal immune system, but their specific effects on innate immune function is not well understood. In a longitudinal study of pregnant women, we investigated innate immune cell function in response to toll-like receptors (TLR) 4 and 7 stimulation, two TLR pathways playing a critical role in early innate immune recognition of bacteria and viruses. IFNα production by TLR7-stimulated pDCs was decreased in early pregnancy, and increased towards the end of pregnancy. In contrast, pro-inflammatory TLR4-induced TNFα production by monocytes was increased during early pregnancy, but declined after the first trimester. Changes in cytokine production were associated with changes in pregnancy-related hormones and monocyte subpopulations over the course of pregnancy. These data demonstrating a significant association between pregnancy-related hormones and modulation of innate immune responses mediated by TLRs provide novel insights into the immunological adaptations occurring during pregnancy.


Assuntos
Células Dendríticas/imunologia , Tolerância Imunológica/imunologia , Monócitos/imunologia , Receptor 4 Toll-Like/metabolismo , Receptor 7 Toll-Like/metabolismo , Gonadotropina Coriônica/sangue , Feminino , Humanos , Imunidade Inata/imunologia , Estudos Longitudinais , Masculino , Gravidez , Estudos Prospectivos , Fator de Necrose Tumoral alfa/sangue
18.
Blood ; 131(17): 1903-1909, 2018 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-29483100

RESUMO

Combinations of proinflammatory and procoagulant reactions are the unifying principle for a variety of disorders affecting the cardiovascular system. The factor XII-driven contact system starts coagulation and inflammatory mechanisms via the intrinsic pathway of coagulation and the bradykinin-producing kallikrein-kinin system, respectively. The biochemistry of the contact system in vitro is well understood; however, its in vivo functions are just beginning to emerge. Challenging the concept of the coagulation balance, targeting factor XII or its activator polyphosphate, provides protection from thromboembolic diseases without interfering with hemostasis. This suggests that the polyphosphate/factor XII axis contributes to thrombus formation while being dispensable for hemostatic processes. In contrast to deficiency in factor XII providing safe thromboprotection, excessive FXII activity is associated with the life-threatening inflammatory disorder hereditary angioedema. The current review summarizes recent findings of the polyphosphate/factor XII-driven contact system at the intersection of procoagulant and proinflammatory disease states. Elucidating the contact system offers the exciting opportunity to develop strategies for safe interference with both thrombotic and inflammatory disorders.


Assuntos
Angioedemas Hereditários/metabolismo , Fator XII/metabolismo , Polifosfatos/metabolismo , Tromboembolia/metabolismo , Trombose/metabolismo , Angioedemas Hereditários/genética , Angioedemas Hereditários/patologia , Fator XII/genética , Humanos , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Tromboembolia/genética , Tromboembolia/patologia , Trombose/genética , Trombose/patologia
19.
PLoS One ; 13(2): e0191150, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29474368

RESUMO

BACKGROUND: Venous thromboembolism (VTE) is a major cause of morbidity and mortality in elderly patients. Extracellular DNA is a pro-inflammatory and pro-thrombotic mediator in vitro and in animal models. Levels of circulating extracellular DNA (ceDNA) are increased in VTE patients, but the association of ceDNA with VTE extent and clinical outcome is poorly understood. OBJECTIVES: We analyzed the association of ceDNA with the extent of VTE, categorized as distal and proximal deep vein thrombosis and pulmonary embolism, and with the clinical outcomes VTE recurrence and mortality. METHODS: We quantified ceDNA by a fluorescent probe, as well as circulating nucleosomes and neutrophil extracellular traps (NETs) by ELISA in plasma from 611 patients aged ≥ 65 years with acute VTE of a prospective cohort study (SWITCO65+). RESULTS: Levels of ceDNA and nucleosomes, but not NETs, correlated with VTE extent. Infectious comorbidities independently increased ceDNA levels in VTE. CeDNA strongly correlated with C-reactive protein and leukocytosis, suggesting an association of ceDNA with inflammation in VTE patients. CeDNA furthermore predicted PE-related and all-cause mortality, but not VTE recurrence, during a 3-year follow-up. CONCLUSIONS: Our study suggests that ceDNA levels in VTE patients reflect the degree of inflammation and may serve as a biomarker to stratify VTE patients at risk for mortality.


Assuntos
DNA/sangue , Tromboembolia Venosa/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Estudos de Coortes , Líquido Extracelular/metabolismo , Armadilhas Extracelulares/metabolismo , Feminino , Humanos , Mediadores da Inflamação/sangue , Masculino , Nucleossomos/metabolismo , Estudos Prospectivos , Embolia Pulmonar/sangue , Embolia Pulmonar/mortalidade , Recidiva , Fatores de Risco , Suíça/epidemiologia , Tromboembolia Venosa/mortalidade , Trombose Venosa/sangue , Trombose Venosa/mortalidade
20.
J Clin Invest ; 128(3): 944-959, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29376892

RESUMO

Coagulation factor XII (FXII) deficiency is associated with decreased neutrophil migration, but the mechanisms remain uncharacterized. Here, we examine how FXII contributes to the inflammatory response. In 2 models of sterile inflammation, FXII-deficient mice (F12-/-) had fewer neutrophils recruited than WT mice. We discovered that neutrophils produced a pool of FXII that is functionally distinct from hepatic-derived FXII and contributes to neutrophil trafficking at sites of inflammation. FXII signals in neutrophils through urokinase plasminogen activator receptor-mediated (uPAR-mediated) Akt2 phosphorylation at S474 (pAktS474). Downstream of pAkt2S474, FXII stimulation of neutrophils upregulated surface expression of αMß2 integrin, increased intracellular calcium, and promoted extracellular DNA release. The sum of these activities contributed to neutrophil cell adhesion, migration, and release of neutrophil extracellular traps in a process called NETosis. Decreased neutrophil signaling in F12-/- mice resulted in less inflammation and faster wound healing. Targeting hepatic F12 with siRNA did not affect neutrophil migration, whereas WT BM transplanted into F12-/- hosts was sufficient to correct the neutrophil migration defect in F12-/- mice and restore wound inflammation. Importantly, these activities were a zymogen FXII function and independent of FXIIa and contact activation, highlighting that FXII has a sophisticated role in vivo that has not been previously appreciated.


Assuntos
Fator XII/metabolismo , Neutrófilos/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Cicatrização , Animais , Cálcio/metabolismo , Adesão Celular , Movimento Celular , Células Cultivadas , Armadilhas Extracelulares , Feminino , Humanos , Inflamação , Leucócitos/citologia , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Peritonite/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/metabolismo , Transdução de Sinais
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