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1.
Br J Haematol ; 196(5): 1159-1169, 2022 03.
Article in English | MEDLINE | ID: covidwho-1583669

ABSTRACT

COVID-19 has compelled scientists to better describe its pathophysiology to find new therapeutic approaches. While risk factors, such as older age, obesity, and diabetes mellitus, suggest a central role of endothelial cells (ECs), autopsies have revealed clots in the pulmonary microvasculature that are rich in neutrophils and DNA traps produced by these cells, called neutrophil extracellular traps (NETs.) Submicron extracellular vesicles, called microparticles (MPs), are described in several diseases as being involved in pro-inflammatory pathways. Therefore, in this study, we analyzed three patient groups: one for which intubation was not necessary, an intubated group, and one group after extubation. In the most severe group, the intubated group, platelet-derived MPs and endothelial cell (EC)-derived MPs exhibited increased concentration and size, when compared to uninfected controls. MPs of intubated COVID-19 patients triggered EC death and overexpression of two adhesion molecules: P-selectin and vascular cell adhesion molecule-1 (VCAM-1). Strikingly, neutrophil adhesion and NET production were increased following incubation with these ECs. Importantly, we also found that preincubation of these COVID-19 MPs with the phosphatidylserine capping endogenous protein, annexin A5, abolished cytotoxicity, P-selectin and VCAM-1 induction, all like increases in neutrophil adhesion and NET release. Taken together, our results reveal that MPs play a key role in COVID-19 pathophysiology and point to a potential therapeutic: annexin A5.


Subject(s)
COVID-19/immunology , Cell-Derived Microparticles/immunology , Endothelial Cells/immunology , Neutrophils/immunology , SARS-CoV-2/immunology , COVID-19/pathology , COVID-19/therapy , Cell Adhesion , Cell Death , Cell-Derived Microparticles/pathology , Cells, Cultured , Endothelial Cells/pathology , Extracellular Traps/immunology , Humans , Inflammation/immunology , Inflammation/pathology , Intubation , Neutrophils/pathology , Phosphatidylserines/immunology
2.
Trends Biochem Sci ; 47(3): 265-278, 2022 03.
Article in English | MEDLINE | ID: covidwho-1550091

ABSTRACT

Cell adhesion is essential for the formation of organs, cellular migration, and interaction with target cells and the extracellular matrix. Integrins are large protein α/ß-chain heterodimers and form a major family of cell adhesion molecules. Recent research has dramatically increased our knowledge of how integrin phosphorylations regulate integrin activity. Phosphorylations determine the signaling complexes formed on the cytoplasmic tails, regulating downstream signaling. α-Chain phosphorylation is necessary for inducing ß-chain phosphorylation in LFA-1, and the crosstalk from one integrin to another activating or inactivating its function is in part mediated by phosphorylation of ß-chains. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus receptor angiotensin-converting enzyme 2 (ACE2) and possible integrin coreceptors may crosstalk and induce a phosphorylation switch and autophagy.


Subject(s)
COVID-19 , Integrins , Cell Adhesion , Humans , Integrins/metabolism , Phosphorylation , SARS-CoV-2
3.
Angiogenesis ; 24(3): 677-693, 2021 08.
Article in English | MEDLINE | ID: covidwho-1549443

ABSTRACT

Endothelial barrier disruption and vascular leak importantly contribute to organ dysfunction and mortality during inflammatory conditions like sepsis and acute respiratory distress syndrome. We identified the kinase Arg/Abl2 as a mediator of endothelial barrier disruption, but the role of Arg in endothelial monolayer regulation and its relevance in vivo remain poorly understood. Here we show that depletion of Arg in endothelial cells results in the activation of both RhoA and Rac1, increased cell spreading and elongation, redistribution of integrin-dependent cell-matrix adhesions to the cell periphery, and improved adhesion to the extracellular matrix. We further show that Arg is activated in the endothelium during inflammation, both in murine lungs exposed to barrier-disruptive agents, and in pulmonary microvessels of septic patients. Importantly, Arg-depleted endothelial cells were less sensitive to barrier-disruptive agents. Despite the formation of F-actin stress fibers and myosin light chain phosphorylation, Arg depletion diminished adherens junction disruption and intercellular gap formation, by reducing the disassembly of cell-matrix adhesions and cell retraction. In vivo, genetic deletion of Arg diminished vascular leak in the skin and lungs, in the presence of a normal immune response. Together, our data indicate that Arg is a central and non-redundant regulator of endothelial barrier integrity, which contributes to cell retraction and gap formation by increasing the dynamics of adherens junctions and cell-matrix adhesions in a Rho GTPase-dependent fashion. Therapeutic inhibition of Arg may provide a suitable strategy for the treatment of a variety of clinical conditions characterized by vascular leak.


Subject(s)
Extracellular Matrix/metabolism , Gap Junctions/enzymology , Human Umbilical Vein Endothelial Cells/enzymology , Protein-Tyrosine Kinases/metabolism , Pulmonary Alveoli/enzymology , Animals , Cell Adhesion/genetics , Enzyme Activation , Extracellular Matrix/genetics , Gap Junctions/genetics , Humans , Inflammation/enzymology , Inflammation/genetics , Mice , Mice, Knockout , Protein-Tyrosine Kinases/genetics
4.
Int J Mol Sci ; 22(21)2021 Nov 07.
Article in English | MEDLINE | ID: covidwho-1512380

ABSTRACT

Heparin and its derivatives are saving thousands of human lives annually, by successfully preventing and treating thromboembolic events. Although the mode of action during anticoagulation is well studied, their influence on cell behavior is not fully understood as is the risk of bleeding and other side effects. New applications in regenerative medicine have evolved supporting production of cell-based therapeutics or as a substrate for creating functionalized matrices in biotechnology. The currently resurgent interest in heparins is related to the expected combined anti-inflammatory, anti-thrombotic and anti-viral action against COVID-19. Based on a concise summary of key biochemical and clinical data, this review summarizes the impact for manufacturing and application of cell therapeutics and highlights the need for discriminating the different heparins.


Subject(s)
Anticoagulants/chemistry , Cell- and Tissue-Based Therapy/methods , Heparin/analogs & derivatives , Anticoagulants/adverse effects , Anticoagulants/therapeutic use , Biocompatible Materials/chemistry , Biocompatible Materials/therapeutic use , Cell Adhesion , Hemorrhage/etiology , Heparin/adverse effects , Heparin/therapeutic use , Humans , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Regenerative Medicine , Thromboembolism/drug therapy
5.
Int J Mol Sci ; 22(21)2021 Nov 01.
Article in English | MEDLINE | ID: covidwho-1512379

ABSTRACT

The research presented herein follows an urgent global need for the development of novel surface engineering techniques that would allow the fabrication of next-generation cardiovascular stents, which would drastically reduce cardiovascular diseases (CVD). The combination of hydrothermal treatment (HT) and treatment with highly reactive oxygen plasma (P) allowed for the formation of an oxygen-rich nanostructured surface. The morphology, surface roughness, chemical composition and wettability of the newly prepared oxide layer on the Ti substrate were characterized by scanning electron microscopy (SEM) with energy-dispersive X-ray analysis (EDX), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and water contact angle (WCA) analysis. The alteration of surface characteristics influenced the material's bio-performance; platelet aggregation and activation was reduced on surfaces treated by hydrothermal treatment, as well as after plasma treatment. Moreover, it was shown that surfaces treated by both treatment procedures (HT and P) promoted the adhesion and proliferation of vascular endothelial cells, while at the same time inhibiting the adhesion and proliferation of vascular smooth muscle cells. The combination of both techniques presents a novel approach for the fabrication of vascular implants, with superior characteristics.


Subject(s)
Endothelial Cells/cytology , Muscle, Smooth, Vascular/cytology , Plasma/chemistry , Titanium/chemistry , Cell Adhesion , Cell Line , Cell Proliferation , Humans , Microscopy, Atomic Force , Microscopy, Electron, Scanning , Nanostructures , Particle Size , Stents , Surface Properties , Wettability
6.
Nat Commun ; 12(1): 5552, 2021 09 21.
Article in English | MEDLINE | ID: covidwho-1434105

ABSTRACT

Sepsis is a life-threatening condition caused by the extreme release of inflammatory mediators into the blood in response to infection (e.g., bacterial infection, COVID-19), resulting in the dysfunction of multiple organs. Currently, there is no direct treatment for sepsis. Here we report an abiotic hydrogel nanoparticle (HNP) as a potential therapeutic agent for late-stage sepsis. The HNP captures and neutralizes all variants of histones, a major inflammatory mediator released during sepsis. The highly optimized HNP has high capacity and long-term circulation capability for the selective sequestration and neutralization of histones. Intravenous injection of the HNP protects mice against a lethal dose of histones through the inhibition of platelet aggregation and migration into the lungs. In vivo administration in murine sepsis model mice results in near complete survival. These results establish the potential for synthetic, nonbiological polymer hydrogel sequestrants as a new intervention strategy for sepsis therapy and adds to our understanding of the importance of histones to this condition.


Subject(s)
Hydrogels/therapeutic use , Nanoparticles/therapeutic use , Sepsis/drug therapy , Animals , Blood Platelets/drug effects , Cell Adhesion , Cell Survival/drug effects , Disease Models, Animal , Histones/antagonists & inhibitors , Histones/metabolism , Histones/toxicity , Hydrogels/chemistry , Hydrogels/metabolism , Hydrogels/pharmacology , Lung/drug effects , Lung/metabolism , Lung/pathology , Mice , Nanoparticles/chemistry , Nanoparticles/metabolism , Platelet Aggregation/drug effects , Polyethylene Glycols/chemistry , Polyethylene Glycols/metabolism , Polyethylene Glycols/pharmacology , Polyethylene Glycols/therapeutic use , Protein Binding , Sepsis/mortality , Survival Rate
7.
Viruses ; 13(9)2021 09 17.
Article in English | MEDLINE | ID: covidwho-1430976

ABSTRACT

Human leukocyte antigen (HLA) is a group of molecules involved in inflammatory and infective responses. We evaluated blood sHLA-E and sHLA-G levels in hospitalized COVID-19 patients with respiratory failure and their relationship with clinical evolution, changes in endothelial activation biomarker profile, and neutrophil adhesion. sHLA-E, sHLA-G, and endothelial activation biomarkers were quantified by ELISA assay in plasma samples. Neutrophil adhesion to endothelium was assessed in the presence/absence of patients' plasma samples. At admission, plasma levels of sHLA-G and sHLA-E were significantly higher in COVID-19 patients with respiratory failure compared to controls. COVID-19 clinical improvement was associated with increased sHLA-G plasma levels. In COVID-19, but not in control patients, an inverse correlation was found between serum sICAM-1 and E-selectin levels and plasma sHLA-G values. The in vitro analysis of activated endothelial cells confirmed the ability of HLA-G molecules to control sICAM-1 and sE-selectin expression via CD160 interaction and FGF2 induction and consequently neutrophil adhesion. We suggest a potential role for sHLA-G in improving COVID-19 patients' clinical condition related to the control of neutrophil adhesion to activated endothelium.


Subject(s)
Biomarkers , COVID-19/immunology , COVID-19/virology , HLA-G Antigens/immunology , Neutrophils/immunology , SARS-CoV-2/immunology , Aged , Alleles , COVID-19/epidemiology , Cell Adhesion/immunology , Endothelial Cells/immunology , Endothelial Cells/metabolism , Enzyme-Linked Immunosorbent Assay , Female , Gene Frequency , HLA-G Antigens/blood , Humans , Male , Middle Aged , Models, Biological , Neutrophils/metabolism
8.
Molecules ; 26(17)2021 Aug 27.
Article in English | MEDLINE | ID: covidwho-1403854

ABSTRACT

This paper presents the results of the first part of testing a novel electrospun fiber mat based on a unique macromolecule: polyisobutylene (PIB). A PIB-based compound containing zinc oxide (ZnO) was electrospun into self-supporting mats of 203.75 and 295.5 g/m2 that were investigated using a variety of techniques. The results show that the hydrophobic mats are not cytotoxic, resist fibroblast cell adhesion and biofilm formation and are comfortable and easy to breathe through for use as a mask. The mats show great promise for personal protective equipment and other applications.


Subject(s)
Polyenes/chemistry , Polymers/chemistry , Biofilms/drug effects , Cell Adhesion/drug effects , Cells, Cultured , Fibroblasts/drug effects , Humans , Materials Testing/methods , Nanofibers/chemistry , Zinc Oxide/chemistry
9.
Int J Mol Sci ; 22(9)2021 Apr 27.
Article in English | MEDLINE | ID: covidwho-1390655

ABSTRACT

The identification of thrombospondin-1 as an angiogenesis inhibitor in 1990 prompted interest in its role in cancer biology and potential as a therapeutic target. Decreased thrombospondin-1 mRNA and protein expression are associated with progression in several cancers, while expression by nonmalignant cells in the tumor microenvironment and circulating levels in cancer patients can be elevated. THBS1 is not a tumor suppressor gene, but the regulation of its expression in malignant cells by oncogenes and tumor suppressor genes mediates some of their effects on carcinogenesis, tumor progression, and metastasis. In addition to regulating angiogenesis and perfusion of the tumor vasculature, thrombospondin-1 limits antitumor immunity by CD47-dependent regulation of innate and adaptive immune cells. Conversely, thrombospondin-1 is a component of particles released by immune cells that mediate tumor cell killing. Thrombospondin-1 differentially regulates the sensitivity of malignant and nonmalignant cells to genotoxic stress caused by radiotherapy and chemotherapy. The diverse activities of thrombospondin-1 to regulate autophagy, senescence, stem cell maintenance, extracellular vesicle function, and metabolic responses to ischemic and genotoxic stress are mediated by several cell surface receptors and by regulating the functions of several secreted proteins. This review highlights progress in understanding thrombospondin-1 functions in cancer and the challenges that remain in harnessing its therapeutic potential.


Subject(s)
Neoplasms , Thrombospondin 1/physiology , Tumor Microenvironment/physiology , Animals , Cell Adhesion , Cell Movement , Humans , Integrins/metabolism , Mice , Neoplasms/blood supply , Neoplasms/immunology , Neoplasms/pathology , Neovascularization, Pathologic/metabolism , Neovascularization, Physiologic/genetics , T-Lymphocytes/immunology , Thrombospondin 1/genetics , Thrombospondin 1/metabolism
10.
J Virol ; 95(17): e0079421, 2021 08 10.
Article in English | MEDLINE | ID: covidwho-1350003

ABSTRACT

Increased mortality in COVID-19 cases is often associated with microvascular complications. We have recently shown that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein promotes an inflammatory cytokine interleukin 6 (IL-6)/IL-6R-induced trans signaling response and alarmin secretion. Virus-infected or spike-transfected human epithelial cells exhibited an increase in senescence, with a release of senescence-associated secretory phenotype (SASP)-related inflammatory molecules. Introduction of the bromodomain-containing protein 4 (BRD4) inhibitor AZD5153 to senescent epithelial cells reversed this effect and reduced SASP-related inflammatory molecule release in TMNK-1 or EAhy926 (representative human endothelial cell lines), when cells were exposed to cell culture medium (CM) derived from A549 cells expressing SARS-CoV-2 spike protein. Cells also exhibited a senescence phenotype with enhanced p16, p21, and senescence-associated ß-galactosidase (SA-ß-Gal) expression and triggered SASP pathways. Inhibition of IL-6 trans signaling by tocilizumab and inhibition of inflammatory receptor signaling by the Bruton's tyrosine kinase (BTK) inhibitor zanubrutinib, prior to exposure of CM to endothelial cells, inhibited p21 and p16 induction. We also observed an increase in reactive oxygen species (ROS) in A549 spike-transfected and endothelial cells exposed to spike-transfected CM. ROS generation in endothelial cell lines was reduced after treatment with tocilizumab and zanubrutinib. Cellular senescence was associated with an increased level of the endothelial adhesion molecules vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1), which have in vitro leukocyte attachment potential. Inhibition of senescence or SASP function prevented VCAM-1/ICAM-1 expression and leukocyte attachment. Taken together, we identified that human endothelial cells exposed to cell culture supernatant derived from SARS-CoV-2 spike protein expression displayed cellular senescence markers, leading to enhanced leukocyte adhesion. IMPORTANCE The present study was aimed at examining the underlying mechanism of extrapulmonary manifestations of SARS-CoV-2 spike protein-associated pathogenesis, with the notion that infection of the pulmonary epithelium can lead to mediators that drive endothelial dysfunction. We utilized SARS-CoV-2 spike protein expression in cultured human hepatocytes (Huh7.5) and pneumocytes (A549) to generate conditioned culture medium (CM). Endothelial cell lines (TMNK-1 or EAhy926) treated with CM exhibited an increase in cellular senescence markers by a paracrine mode and led to leukocyte adhesion. Overall, the link between these responses in endothelial cell senescence and a potential contribution to microvascular complication in productively SARS-CoV-2-infected humans is implicated. Furthermore, the use of inhibitors (BTK, IL-6, and BRD4) showed a reverse effect in the senescent cells. These results may support the selection of potential adjunct therapeutic modalities to impede SARS-CoV-2-associated pathogenesis.


Subject(s)
Cellular Senescence , Endothelial Cells/metabolism , Leukocytes/metabolism , Paracrine Communication , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/metabolism , A549 Cells , Cell Adhesion , Cell Cycle Proteins/antagonists & inhibitors , Cell Cycle Proteins/metabolism , Endothelial Cells/pathology , Endothelial Cells/virology , Heterocyclic Compounds, 2-Ring/pharmacology , Humans , Intercellular Adhesion Molecule-1/metabolism , Interleukin-6/metabolism , Leukocytes/pathology , Leukocytes/virology , Piperazines/pharmacology , Pyrazoles , Pyridazines , Reactive Oxygen Species/metabolism , Receptors, Interleukin-6/metabolism , Signal Transduction , Transcription Factors/antagonists & inhibitors , Transcription Factors/metabolism , Vascular Cell Adhesion Molecule-1/metabolism
11.
Molecules ; 26(15)2021 Jul 29.
Article in English | MEDLINE | ID: covidwho-1346516

ABSTRACT

We recently developed a molecule (GT-73) that blocked leukocyte transendothelial migration from blood to the peripheral tissues, supposedly by affecting the platelet endothelial cell adhesion molecule (PECAM-1) function. GT-73 was tested in an LPS-induced acute respiratory distress syndrome (ARDS) mouse model. The rationale for this is based on the finding that the mortality of COVID-19 patients is partly caused by ARDS induced by a massive migration of leukocytes to the lungs. In addition, the role of tert-butyl and methyl ester moieties in the biological effect of GT-73 was investigated. A human leukocyte, transendothelial migration assay was applied to validate the blocking effect of GT-73 derivatives. Finally, a mouse model of LPS-induced ARDS was used to evaluate the histological and biochemical effects of GT-73. The obtained results showed that GT-73 has a unique structure that is responsible for its biological activity; two of its chemical moieties (tert-butyl and a methyl ester) are critical for this effect. GT-73 is a prodrug, and its lipophilic tail covalently binds to PECAM-1 via Lys536. GT-73 significantly decreased the number of infiltrating leukocytes in the lungs and reduced the inflammation level. Finally, GT-73 reduced the levels of IL-1ß, IL-6, and MCP-1 in bronchoalveolar lavage fluid (BALF). In summary, we concluded that GT-73, a blocker of white blood cell transendothelial migration, has a favorable profile as a drug candidate for the treatment of ARDS in COVID-19 patients.


Subject(s)
COVID-19/drug therapy , Leukocytes/drug effects , Platelet Endothelial Cell Adhesion Molecule-1/antagonists & inhibitors , Pyrimidines/pharmacology , Respiratory Distress Syndrome/drug therapy , Transendothelial and Transepithelial Migration/drug effects , Animals , COVID-19/pathology , Cell Adhesion/drug effects , Cell Adhesion/immunology , Cell Movement/drug effects , Cytokine Release Syndrome/drug therapy , Cytokines/metabolism , Disease Models, Animal , Female , Humans , Leukocytes/immunology , Lipopolysaccharides/adverse effects , Mice , Mice, Inbred BALB C , Platelet Endothelial Cell Adhesion Molecule-1/immunology , Pyrimidines/chemistry , Respiratory Distress Syndrome/chemically induced , SARS-CoV-2
12.
Cells ; 10(7)2021 Jul 06.
Article in English | MEDLINE | ID: covidwho-1295777

ABSTRACT

Integrins belong to a group of cell adhesion molecules (CAMs) which is a large group of membrane-bound proteins. They are responsible for cell attachment to the extracellular matrix (ECM) and signal transduction from the ECM to the cells. Integrins take part in many other biological activities, such as extravasation, cell-to-cell adhesion, migration, cytokine activation and release, and act as receptors for some viruses, including severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2). They play a pivotal role in cell proliferation, migration, apoptosis, tissue repair and are involved in the processes that are crucial to infection, inflammation and angiogenesis. Integrins have an important part in normal development and tissue homeostasis, and also in the development of pathological processes in the eye. This review presents the available evidence from human and animal research into integrin structure, classification, function and their role in inflammation, infection and angiogenesis in ocular diseases. Integrin receptors and ligands are clinically interesting and may be promising as new therapeutic targets in the treatment of some eye disorders.


Subject(s)
Eye Diseases/metabolism , Inflammation/metabolism , Integrins/metabolism , Neovascularization, Pathologic/metabolism , Animals , COVID-19/metabolism , COVID-19/pathology , Cell Adhesion , Extracellular Matrix/metabolism , Extracellular Matrix/pathology , Eye Diseases/pathology , Humans , Inflammation/pathology , Integrins/analysis , Neovascularization, Pathologic/pathology , SARS-CoV-2/metabolism
14.
Viruses ; 13(4)2021 04 09.
Article in English | MEDLINE | ID: covidwho-1178431

ABSTRACT

The spike glycoprotein attached to the envelope of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) binds to and exploits angiotensin-converting enzyme 2 (ACE2) as an entry receptor to infect pulmonary epithelial cells. A subset of integrins that recognize the arginyl-glycyl-aspartic acid (RGD) sequence in the cognate ligands has been predicted in silico to bind the spike glycoprotein and, thereby, to be exploited for viral infection. Here, we show experimental evidence that the ß1 integrins predominantly expressed on human pulmonary epithelial cell lines and primary mouse alveolar epithelial cells bind to this spike protein. The cellular ß1 integrins support adhesive interactions with the spike protein independently of ACE2, suggesting the possibility that the ß1 integrins may function as an alternative receptor for SARS-CoV-2, which could be targeted for the prevention of viral infections.


Subject(s)
Alveolar Epithelial Cells/metabolism , Integrin beta1/metabolism , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/metabolism , Angiotensin-Converting Enzyme 2/metabolism , Animals , COVID-19/virology , Cell Adhesion , Cell Line , Humans , Lung/metabolism , Mice , Mice, Inbred C57BL , Oligopeptides , Protein Binding , Receptors, Virus/metabolism , THP-1 Cells , Virus Internalization
15.
Life Sci ; 276: 119376, 2021 Jul 01.
Article in English | MEDLINE | ID: covidwho-1157590

ABSTRACT

The severe forms and worsened outcomes of COVID-19 (coronavirus disease 19) are closely associated with hypertension and cardiovascular disease. Endothelial cells express Angiotensin-Converting Enzyme 2 (ACE2), which is the entrance door for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The hallmarks of severe illness caused by SARS-CoV-2 infection are increased levels of IL-6, C-reactive protein, D-dimer, ferritin, neutrophilia and lymphopenia, pulmonary intravascular coagulopathy and microthrombi of alveolar capillaries. The endothelial glycocalyx, a proteoglycan- and glycoprotein-rich layer covering the luminal side of endothelial cells, contributes to vascular homeostasis. It regulates vascular tonus and permeability, prevents thrombosis, and modulates leukocyte adhesion and inflammatory response. We hypothesized that cytokine production and reactive oxygen species (ROS) generation associated with COVID-19 leads to glycocalyx degradation. A cohort of 20 hospitalized patients with a confirmed COVID-19 diagnosis and healthy subjects were enrolled in this study. Mechanisms associated with glycocalyx degradation in COVID-19 were investigated. Increased plasma concentrations of IL-6 and IL1-ß, as well as increased lipid peroxidation and glycocalyx components were detected in plasma from COVID-19 patients compared to plasma from healthy subjects. Plasma from COVID-19 patients induced glycocalyx shedding in cultured human umbilical vein endothelial cells (HUVECs) and disrupted redox balance. Treatment of HUVECs with low molecular weight heparin inhibited the glycocalyx perturbation. In conclusion, plasma from COVID-19 patients promotes glycocalyx shedding and redox imbalance in endothelial cells, and heparin treatment potentially inhibits glycocalyx disruption.


Subject(s)
COVID-19/blood , COVID-19/pathology , Glycocalyx/pathology , Heparin/pharmacology , Aged , Blood Coagulation Disorders/blood , Blood Coagulation Disorders/virology , COVID-19/metabolism , COVID-19 Testing , Case-Control Studies , Cell Adhesion/physiology , Endothelium, Vascular/metabolism , Female , Glycocalyx/metabolism , Glycocalyx/virology , Human Umbilical Vein Endothelial Cells , Humans , Interleukin-1beta/blood , Interleukin-6/blood , Male , Middle Aged , Oxidation-Reduction , SARS-CoV-2 , Thrombosis/metabolism
16.
J Am Soc Nephrol ; 31(2): 297-307, 2020 02.
Article in English | MEDLINE | ID: covidwho-992922

ABSTRACT

BACKGROUND: Myeloperoxidase-specific ANCA (MPO-ANCA) are implicated in the pathogenesis of vasculitis and GN. Kinins play a major role during acute inflammation by regulating vasodilatation and vascular permeability and by modulating adhesion and migration of leukocytes. Kinin system activation occurs in patients with ANCA vasculitis. Previous studies in animal models of GN and sclerosing kidney diseases have demonstrated protective effects of bradykinin receptor 1 (B1R) blockade via interference with myeloid cell trafficking. METHODS: To investigate the role of B1R in a murine model of MPO-ANCA GN, we evaluated effects of B1R genetic ablation and pharmacologic blockade. We used bone marrow chimeric mice to determine the role of B1R in bone marrow-derived cells (leukocytes) versus nonbone marrow-derived cells. We elucidated mechanisms of B1R effects using in vitro assays for MPO-ANCA-induced neutrophil activation, endothelial adherence, endothelial transmigration, and neutrophil adhesion molecule surface display. RESULTS: B1R deficiency or blockade prevented or markedly reduced ANCA-induced glomerular crescents, necrosis, and leukocyte influx in mice. B1R was not required for in vitro MPO-ANCA-induced neutrophil activation. Leukocyte B1R deficiency, but not endothelial B1R deficiency, decreased glomerular neutrophil infiltration induced by MPO-ANCA in vivo. B1R enhanced ANCA-induced neutrophil endothelial adhesion and transmigration in vitro. ANCA-activated neutrophils exhibited changes in Mac-1 and LFA-1, important regulators of neutrophil endothelial adhesion and transmigration: ANCA-activated neutrophils increased surface expression of Mac-1 and increased shedding of LFA-1, whereas B1R blockade reduced these effects. CONCLUSIONS: The leukocyte B1R plays a critical role in the pathogenesis of MPO-ANCA-induced GN in a mouse model by modulating neutrophil-endothelial interaction. B1R blockade may have potential as a therapy for ANCA GN and vasculitis.


Subject(s)
Antibodies, Antineutrophil Cytoplasmic/immunology , Glomerulonephritis/etiology , Peroxidase/immunology , Receptor, Bradykinin B1/physiology , Animals , Bradykinin B1 Receptor Antagonists/therapeutic use , Cell Adhesion , Disease Models, Animal , Endothelial Cells/physiology , Glomerulonephritis/drug therapy , Mice , Mice, Inbred C57BL , Neutrophils/physiology
17.
Epigenomics ; 12(22): 1969-1981, 2020 11.
Article in English | MEDLINE | ID: covidwho-948022

ABSTRACT

Aim: To elucidate the transcriptional characteristics of COVID-19. Materials & methods: We utilized an integrative approach to comprehensively analyze the transcriptional features of both COVID-19 patients and SARS-CoV-2 infected cells. Results: Widespread infiltration of immune cells was observed. We identified 233 genes that were codifferentially expressed in both bronchoalveolar lavage fluid and lung samples of COVID-19 patients. Functional analysis suggested upregulated genes were related to immune response such as neutrophil activation and antivirus response, while downregulated genes were associated with cell adhesion. Finally, we identified LCN2, STAT1 and UBE2L6 as core genes during SARS-CoV-2 infection. Conclusion: The identification of core genes involved in COVID-19 can provide us with more insights into the molecular features of COVID-19.


Subject(s)
COVID-19/pathology , Lipocalin-2/genetics , SARS-CoV-2/immunology , STAT1 Transcription Factor/genetics , Ubiquitin-Conjugating Enzymes/genetics , A549 Cells , Bronchoalveolar Lavage Fluid/cytology , COVID-19/immunology , Cell Adhesion/genetics , Cell Adhesion/physiology , Cell Line, Tumor , Cytokines/blood , Humans , Lung/immunology , Neutrophil Activation/genetics , Neutrophil Activation/immunology , SARS-CoV-2/genetics , Transcription, Genetic/genetics
18.
Vaccine ; 38(48): 7629-7637, 2020 11 10.
Article in English | MEDLINE | ID: covidwho-879777

ABSTRACT

This work demonstrates the presence of immune regulatory cells in the cervical lymph nodes draining Bacillus Calmette-Guérin (BCG) vaccinated site on the dorsum of the ear in guinea pigs. It is shown that whole cervical lymph node cells did not proliferate in vitro in the presence of soluble mycobacterial antigens (PPD or leprosin) despite being responsive to whole mycobacteria. Besides, T cells from these lymph nodes separated as a non-adherent fraction on a nylon wool column, proliferated to PPD in the presence of autologous antigen presenting cells. Interestingly, addition of as low as 20% nylon wool adherent cells to these, sharply decreased the proliferation by 83%. Looking into what cells in the adherent fraction suppressed the proliferation, it was found that neither the T cell nor the macrophage enriched cell fractions of this population individually showed suppressive effect, indicating that their co-presence was necessary for the suppression. Since BCG induced granulomas resolve much faster than granulomas induced by other mycobacteria such as Mycobacterium leprae the present experimental findings add to the existing evidence that intradermal BCG vaccination influences subsequent immune responses in the host and may further stress upon its beneficial role seen in Covid-19 patients.


Subject(s)
Antigens, Bacterial/pharmacology , BCG Vaccine/pharmacology , Granuloma/immunology , Lymph Nodes/immunology , T-Lymphocytes/immunology , Tuberculin/pharmacology , Animals , Antigen-Presenting Cells/drug effects , Antigen-Presenting Cells/immunology , Antigen-Presenting Cells/microbiology , COVID-19 , Cell Adhesion , Cell Proliferation , Coronavirus Infections/prevention & control , Ear , Female , Granuloma/microbiology , Guinea Pigs , Humans , Injections, Intradermal , Lymph Nodes/microbiology , Macrophages/drug effects , Macrophages/immunology , Macrophages/microbiology , Male , Mycobacterium bovis/immunology , Mycobacterium leprae/immunology , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Remission, Spontaneous , T-Lymphocytes/classification , T-Lymphocytes/drug effects , T-Lymphocytes/microbiology
19.
J Infect Dis ; 222(11): 1789-1793, 2020 Nov 09.
Article in English | MEDLINE | ID: covidwho-722491

ABSTRACT

Beside the commonly described pulmonary expression of the coronavirus disease 2019 (COVID-19), major vascular events have been reported. The objective of this study was to investigate whether increased levels of circulating endothelial cells (CECs) might be associated with severe forms of COVID-19. Ninety-nine patients with COVID-19 were enrolled in this retrospective study. Patients in the intensive care units (ICU) had significantly higher CEC counts than non-ICU patients and the extent of endothelial injury was correlated with putative markers of disease severity and inflammatory cytokines. Together, these data provide in vivo evidence that endothelial injury is a key feature of COVID-19.


Subject(s)
COVID-19/pathology , Endothelium, Vascular/pathology , Adult , Aged , Biomarkers/analysis , COVID-19/blood , COVID-19/virology , Cell Adhesion/physiology , Endothelium, Vascular/virology , Female , Humans , Intensive Care Units , Male , Middle Aged , Retrospective Studies , SARS-CoV-2/isolation & purification
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