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2.
Clin Appl Thromb Hemost ; 27: 10760296211048808, 2021.
Article in English | MEDLINE | ID: covidwho-1495924

ABSTRACT

We aimed to investigate association between mean platelet volume (MVP), platelet distribution width (PDW) and red cell distribution width (RDW) and mortality in patients with COVID-19 and find out in which patients the use of acetylsalicylic acid (ASA) affects the prognosis due to the effect of MPV on thromboxan A2. A total of 5142 patients were divided into those followed in the intensive care unit (ICU) and those followed in the ward. Patient medical records were examined retrospectively. ROC analysis showed that the area under curve (AUC) values were 0.714, 0.750, 0.843 for MPV, RDW and D-Dimer, the cutoff value was 10.45fl, 43.65fl, 500.2 ng/mL respectively. (all P < .001). Survival analysis showed that patients with MPV >10.45 f/l and D-Dimer >500.2 ng/mL, treatment with ASA had lower in-hospital and 180-day mortality than patients without ASA in ICU patients (HR = 0.773; 95% CI = 0.595-0.992; P = .048, HR = 0.763; 95% CI = 0.590-0.987; P = .036). Administration of low-dose ASA in addition to anti-coagulant according to MPV and D-dimer levels reduces mortality.


Subject(s)
Blood Platelets , COVID-19/blood , Erythrocyte Indices , Erythrocytes , Mean Platelet Volume , Aged , Aged, 80 and over , Anticoagulants/therapeutic use , Aspirin/therapeutic use , Blood Platelets/drug effects , COVID-19/diagnosis , COVID-19/drug therapy , COVID-19/mortality , Female , Hospital Mortality , Humans , Male , Middle Aged , Platelet Aggregation Inhibitors/therapeutic use , Predictive Value of Tests , Retrospective Studies , Severity of Illness Index , Time Factors , Treatment Outcome
3.
Eur Rev Med Pharmacol Sci ; 25(19): 5904-5912, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1478932

ABSTRACT

OBJECTIVE: Liver injury has been reported in patients with COVID-19. This condition is characterized by severe outcome and could be related with the ability of SARS-CoV-2 to activate cytotoxic T cells. The purpose of this study is to show the histological and scanning electron microscopy features of liver involvement in COVID-19 to characterize the liver changes caused by the activation of multiple molecular pathways following this infection. PATIENTS AND METHODS: Liver biopsies from 4 patients (3 post-mortems and 1 in vivo) with COVID-19 were analyzed with histology and by scanning electron microscopy. RESULTS: The liver changes showed significant heterogeneity. The first case showed ground glass hepatocytes and scattered fibrin aggregates in the sinusoidal lumen. The second evidenced intra-sinusoidal thrombi. The third was characterized by sinusoidal dilatation, atrophy of hepatocytes, Disse's spaces dilatation and intra-sinusoidal aggregates of fibrin and red blood cells. The fourth case exhibited diffuse fibrin aggregates in the dilated Disse spaces and microthrombi in the sinusoidal lumen. CONCLUSIONS: In COVID-19-related liver injury, a large spectrum of pathological changes was observed. The most peculiar features were very mild inflammation, intra-sinusoidal changes, including sinusoidal dilatation, thrombotic sinusoiditis and diffuse intra-sinusoidal fibrin deposition. These findings suggested that a thrombotic sinusoiditis followed by a local diffuse intra-vascular (intra-sinusoidal) coagulation could be the typical features of the SARS-CoV-2-related liver injury.


Subject(s)
Blood Coagulation Disorders/pathology , COVID-19/pathology , Liver Diseases/pathology , Liver/pathology , Thrombosis/pathology , Aged , Autopsy , Biopsy , Erythrocytes/pathology , Fibrin , Hepatocytes/pathology , Humans , Male , Microscopy, Electron, Scanning , Middle Aged , Thrombosis/complications , Young Adult
4.
Sci Rep ; 11(1): 20502, 2021 10 15.
Article in English | MEDLINE | ID: covidwho-1469992

ABSTRACT

The COVID-19 is difficult to contain due to its high transmissibility rate and a long incubation period of 5 to 14 days. Moreover, more than half of the infected patients were young and asymptomatic. Virus transmission through asymptomatic patients is a major challenge to disease containment. Due to limited treatment options, preventive measures play major role in controlling the disease spread. Gargling with antiseptic formulation may have potential role in eliminating the virus in the throat. Four commercially available mouthwash/gargle formulations were tested for virucidal activity against SARS-CoV-2 in both clean (0.3 g/l BSA) and dirty (0.3 g/l BSA + 3 mL/L human erythrocytes) conditions at time points 30 and 60 s. The virus was isolated and propagated in Vero E6 cells. The cytotoxicity of the products to the Vero E6 was evaluated by kill time assay based on the European Standard EN14476:2013/FprA1:2015 protocol. Virus titres were calculated as 50% tissue culture infectious dose (TCID50/mL) using the Spearman-Karber method. A reduction in virus titer of 4 log10 corresponds to an inactivation of ≥ 99.99%. Formulations with cetylperidinium chloride, chlorhexidine and hexitidine achieved > 4 log10 reduction in viral titres when exposed within 30 s under both clean and dirty conditions. Thymol formulations achieved only 0.5 log10 reduction in viral titres. In addition, salt water was not proven effective. Gargle formulations with cetylperidinium chloride, chlorhexidine and hexetidine have great potential in reducing SAR-CoV-2 at the source of entry into the body, thus minimizing risk of transmission of COVID-19.


Subject(s)
COVID-19/drug therapy , COVID-19/prevention & control , Erythrocytes/virology , Mouthwashes , SARS-CoV-2/drug effects , Animals , Anti-Infective Agents, Local , Antiviral Agents , Cetylpyridinium , Chlorhexidine/analogs & derivatives , Chlorhexidine/chemistry , Chlorocebus aethiops , Erythrocytes/drug effects , Humans , Thymol/chemistry , Vero Cells , Viral Load , Water
6.
Life Sci Alliance ; 4(11)2021 11.
Article in English | MEDLINE | ID: covidwho-1404295

ABSTRACT

High levels of autoimmune antibodies are observed in COVID-19 patients but their specific contribution to disease severity and clinical manifestations remains poorly understood. We performed a retrospective study of 115 COVID-19 hospitalized patients with different degrees of severity to analyze the generation of autoimmune antibodies to common antigens: a lysate of erythrocytes, the lipid phosphatidylserine (PS) and DNA. High levels of IgG autoantibodies against erythrocyte lysates were observed in a large percentage (up to 36%) of patients. Anti-DNA and anti-PS antibodies determined upon hospital admission correlated strongly with later development of severe disease, showing a positive predictive value of 85.7% and 92.8%, respectively. Patients with positive values for at least one of the two autoantibodies accounted for 24% of total severe cases. Statistical analysis identified strong correlations between anti-DNA antibodies and markers of cell injury, coagulation, neutrophil levels and erythrocyte size. Anti-DNA and anti-PS autoantibodies may play an important role in the pathogenesis of COVID-19 and could be developed as predictive biomarkers for disease severity and specific clinical manifestations.


Subject(s)
Antibodies, Antinuclear/immunology , Autoantibodies/immunology , COVID-19/immunology , COVID-19/metabolism , Adult , Aged , Aged, 80 and over , Antibodies, Antinuclear/blood , Autoantibodies/blood , Biomarkers , DNA/chemistry , DNA/immunology , Erythrocytes/immunology , Female , Humans , Male , Middle Aged , Phosphatidylserines/immunology , Prognosis , Retrospective Studies , SARS-CoV-2/isolation & purification , Severity of Illness Index
8.
Med Hypotheses ; 144: 109976, 2020 Nov.
Article in English | MEDLINE | ID: covidwho-1386300

ABSTRACT

Several attempts to control the dreadfulness of SARS-CoV-2 are still underway. Based on the literature evidences we have speculated a prospective contemporary remedy, which was categorized into Specificity, Remedy, and a Conveyor. In which, pros and cons were discussed and inferred the possible alternatives. (a) Specificity: Implicit to express the ACE2 receptors in conveyor cells to deceive SARS-CoV-2 frompreponetargets. (b) Remedy: As depletion of pulmonary surfactants causes strong acute respiratory distress syndrome, we propose an entity of a cost-effective artificialsurfactantsystem as a remedy to pulmonary complications. (c) Conveyor: We propose red blood cells (RBCs) as a conveyor with embedded artificial surfactant and protruding ACE2 receptors for the target-specific delivery. Overall we postulate focused insights by employing a combinational contemporary strategy to steer towards a prospective direction on combating SARS-CoV-2.


Subject(s)
Angiotensin-Converting Enzyme 2/therapeutic use , COVID-19/virology , Erythrocytes , Pulmonary Surfactants/therapeutic use , Receptors, Virus/therapeutic use , SARS-CoV-2/physiology , Viral Tropism , Angiotensin-Converting Enzyme 2/administration & dosage , COVID-19/complications , COVID-19/prevention & control , Drug Costs , Drug Delivery Systems , Humans , Pulmonary Alveoli/drug effects , Pulmonary Alveoli/virology , Pulmonary Surfactants/administration & dosage , Pulmonary Surfactants/chemical synthesis , Pulmonary Surfactants/economics , Receptors, Virus/administration & dosage , Respiratory Distress Syndrome/prevention & control
9.
Int J Mol Sci ; 22(15)2021 Jul 28.
Article in English | MEDLINE | ID: covidwho-1346499

ABSTRACT

Glycosylation is a complex post-translational modification that conveys functional diversity to glycoconjugates. Cell surface glycosylation mediates several biological activities such as induction of the intracellular signaling pathway and pathogen recognition. Red blood cell (RBC) membrane N-glycans determine blood type and influence cell lifespan. Although several proteomic studies have been carried out, the glycosylation of RBC membrane proteins has not been systematically investigated. This work aims at exploring the human RBC N-glycome by high-sensitivity MALDI-MS techniques to outline a fingerprint of RBC N-glycans. To this purpose, the MALDI-TOF spectra of healthy subjects harboring different blood groups were acquired. Results showed the predominant occurrence of neutral and sialylated complex N-glycans with bisected N-acetylglucosamine and core- and/or antennary fucosylation. In the higher mass region, these species presented with multiple N-acetyllactosamine repeating units. Amongst the detected glycoforms, the presence of glycans bearing ABO(H) antigens allowed us to define a distinctive spectrum for each blood group. For the first time, advanced glycomic techniques have been applied to a comprehensive exploration of human RBC N-glycosylation, providing a new tool for the early detection of distinct glycome changes associated with disease conditions as well as for understanding the molecular recognition of pathogens.


Subject(s)
Blood Group Antigens/metabolism , Erythrocytes/metabolism , Glycomics , Polysaccharides/analysis , Protein Processing, Post-Translational , Glycosylation , Humans , Proteomics , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
10.
Int J Mol Sci ; 21(21)2020 Nov 03.
Article in English | MEDLINE | ID: covidwho-1344351

ABSTRACT

Progressive respiratory failure is seen as a major cause of death in severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2)-induced infection. Relatively little is known about the associated morphologic and molecular changes in the circulation of these patients. In particular, platelet and erythrocyte pathology might result in severe vascular issues, and the manifestations may include thrombotic complications. These thrombotic pathologies may be both extrapulmonary and intrapulmonary and may be central to respiratory failure. Previously, we reported the presence of amyloid microclots in the circulation of patients with coronavirus disease 2019 (COVID-19). Here, we investigate the presence of related circulating biomarkers, including C-reactive protein (CRP), serum ferritin, and P-selectin. These biomarkers are well-known to interact with, and cause pathology to, platelets and erythrocytes. We also study the structure of platelets and erythrocytes using fluorescence microscopy (using the markers PAC-1 and CD62PE) and scanning electron microscopy. Thromboelastography and viscometry were also used to study coagulation parameters and plasma viscosity. We conclude that structural pathologies found in platelets and erythrocytes, together with spontaneously formed amyloid microclots, may be central to vascular changes observed during COVID-19 progression, including thrombotic microangiopathy, diffuse intravascular coagulation, and large-vessel thrombosis, as well as ground-glass opacities in the lungs. Consequently, this clinical snapshot of COVID-19 strongly suggests that it is also a true vascular disease and considering it as such should form an essential part of a clinical treatment regime.


Subject(s)
Blood Platelets/pathology , Cardiovascular Diseases/virology , Coronavirus Infections/blood , Coronavirus Infections/pathology , Erythrocytes/pathology , Ferritins/blood , P-Selectin/blood , Pneumonia, Viral/blood , Pneumonia, Viral/pathology , Betacoronavirus/isolation & purification , Blood Coagulation/physiology , Blood Platelets/virology , COVID-19 , Cardiovascular Diseases/blood , Cardiovascular Diseases/pathology , Coronavirus Infections/virology , Erythrocytes/virology , Female , Humans , Male , Middle Aged , Pandemics , Pneumonia, Viral/virology , SARS-CoV-2 , Thrombosis/pathology , Thrombosis/virology
11.
PLoS One ; 16(7): e0254498, 2021.
Article in English | MEDLINE | ID: covidwho-1325435

ABSTRACT

To screen for additional vaccine candidate antigens of Plasmodium pre-erythrocytic stages, fourteen P. falciparum proteins were selected based on expression in sporozoites or their role in establishment of hepatocyte infection. For preclinical evaluation of immunogenicity of these proteins in mice, chimeric P. berghei sporozoites were created that express the P. falciparum proteins in sporozoites as an additional copy gene under control of the uis4 gene promoter. All fourteen chimeric parasites produced sporozoites but sporozoites of eight lines failed to establish a liver infection, indicating a negative impact of these P. falciparum proteins on sporozoite infectivity. Immunogenicity of the other six proteins (SPELD, ETRAMP10.3, SIAP2, SPATR, HT, RPL3) was analyzed by immunization of inbred BALB/c and outbred CD-1 mice with viral-vectored (ChAd63 or ChAdOx1, MVA) vaccines, followed by challenge with chimeric sporozoites. Protective immunogenicity was determined by analyzing parasite liver load and prepatent period of blood stage infection after challenge. Of the six proteins only SPELD immunized mice showed partial protection. We discuss both the low protective immunogenicity of these proteins in the chimeric rodent malaria challenge model and the negative effect on P. berghei sporozoite infectivity of several P. falciparum proteins expressed in the chimeric sporozoites.


Subject(s)
Malaria, Falciparum/parasitology , Plasmodium falciparum/pathogenicity , Animals , Antibodies, Protozoan/immunology , Antibodies, Protozoan/metabolism , Antigens, Protozoan/immunology , Antigens, Protozoan/metabolism , Erythrocytes/metabolism , Female , Malaria Vaccines/therapeutic use , Malaria, Falciparum/genetics , Malaria, Falciparum/immunology , Mice , Mice, Inbred BALB C , Plasmodium falciparum/metabolism , Protozoan Proteins/metabolism , Sporozoites/pathogenicity
12.
Adv Sci (Weinh) ; 8(18): e2100323, 2021 09.
Article in English | MEDLINE | ID: covidwho-1316190

ABSTRACT

Blood cell analysis is a major pillar of biomedical research and healthcare. These analyses are performed in central laboratories. Rapid shipment from collection site to the central laboratories is currently needed because cells and biomarkers degrade rapidly. The dried blood spot from a fingerstick allows the preservation of cellular molecules for months but entire cells are never recovered. Here leucocyte elution is optimized from dried blood spots. Flow cytometry and mRNA expression profiling are used to analyze the recovered cells. 50-70% of the leucocytes that are dried on a polyester solid support via elution after shaking the support with buffer are recovered. While red blood cells lyse upon drying, it is found that the majority of leucocytes are preserved. Leucocytes have an altered structure that is improved by adding fixative in the elution buffer. Leucocytes are permeabilized, allowing an easy staining of all cellular compartments. Common immunophenotyping and mRNAs are preserved. The ability of a new biomarker (CD169) to discriminate between patients with and without Severe Acute Respiratory Syndrome induced by Coronavirus 2 (SARS-CoV-2) infections is also preserved. Leucocytes from blood can be dried, shipped, and/or stored for at least 1 month, then recovered for a wide variety of analyses, potentially facilitating biomedical applications worldwide.


Subject(s)
Communicable Diseases/diagnosis , Diagnostic Tests, Routine/methods , Dried Blood Spot Testing/methods , Hematology/methods , Immunophenotyping/methods , Antibodies, Viral/blood , Biomarkers/blood , Blood Specimen Collection/methods , COVID-19/diagnosis , Cell Separation/methods , Communicable Diseases/virology , Erythrocytes/virology , Flow Cytometry/methods , Humans , Leukocytes/virology , RNA, Messenger/blood , SARS-CoV-2/genetics
13.
Int J Mol Sci ; 22(13)2021 Jun 24.
Article in English | MEDLINE | ID: covidwho-1304662

ABSTRACT

The aim of this study was to evaluate the effect of everolimus, a mammalian target of rapamycin (mTOR) inhibitor, on red blood cell parameters in the context of iron homeostasis in patients with tuberous sclerosis complex (TSC) and evaluate its effect on cell size in vitro. Everolimus has a significant impact on red blood cell parameters in patients with TSC. The most common alteration was microcytosis. The mean MCV value decreased by 9.2%, 12%, and 11.8% after 3, 6, and 12 months of everolimus treatment. The iron level declined during the first 3 months, and human soluble transferrin receptor concentration increased during 6 months of therapy. The size of K562 cells decreased when cultured in the presence of 5 µM everolimus by approximately 8%. The addition of hemin to the cell culture with 5 µM everolimus did not prevent any decrease in cell size. The stage of erythroid maturation did not affect the response to everolimus. Our results showed that the mTOR inhibitor everolimus caused red blood cell microcytosis in vivo and in vitro. This effect is not clearly related to a deficit of iron and erythroid maturation. This observation confirms that mTOR signaling plays a complex role in the control of cell size.


Subject(s)
Cell Size/drug effects , Erythrocytes/drug effects , Erythrocytes/pathology , Protein Kinase Inhibitors/pharmacology , TOR Serine-Threonine Kinases/antagonists & inhibitors , Adolescent , Biomarkers , Cell Differentiation/drug effects , Cell Line , Child , Child, Preschool , Erythrocyte Indices , Erythrocytes/metabolism , Everolimus/administration & dosage , Everolimus/adverse effects , Everolimus/pharmacology , Flow Cytometry , Humans , Iron/metabolism , K562 Cells , Protein Kinase Inhibitors/administration & dosage , Protein Kinase Inhibitors/adverse effects
14.
Am J Physiol Lung Cell Mol Physiol ; 321(2): L485-L489, 2021 08 01.
Article in English | MEDLINE | ID: covidwho-1299247

ABSTRACT

COVID-19, the disease caused by the SARS-CoV-2 virus, can progress to multisystem organ failure and viral sepsis characterized by respiratory failure, arrhythmias, thromboembolic complications, and shock with high mortality. Autopsy and preclinical evidence implicate aberrant complement activation in endothelial injury and organ failure. Erythrocytes express complement receptors and are capable of binding immune complexes; therefore, we investigated complement activation in patients with COVID-19 using erythrocytes as a tool to diagnose complement activation. We discovered enhanced C3b and C4d deposition on erythrocytes in COVID-19 sepsis patients and non-COVID sepsis patients compared with healthy controls, supporting the role of complement in sepsis-associated organ injury. Our data suggest that erythrocytes may contribute to a precision medicine approach to sepsis and have diagnostic value in monitoring complement dysregulation in COVID-19-sepsis and non-COVID sepsis and identifying patients who may benefit from complement targeted therapies.


Subject(s)
COVID-19/complications , Complement Activation/immunology , Complement C3b/immunology , Complement C4b/immunology , Erythrocytes/immunology , Peptide Fragments/immunology , Respiratory Insufficiency/diagnosis , Sepsis/diagnosis , COVID-19/immunology , COVID-19/virology , Complement C3b/metabolism , Complement C4b/metabolism , Erythrocytes/metabolism , Erythrocytes/virology , Female , Humans , Male , Middle Aged , Peptide Fragments/metabolism , Respiratory Insufficiency/immunology , Respiratory Insufficiency/metabolism , Respiratory Insufficiency/virology , SARS-CoV-2/isolation & purification , Sepsis/immunology , Sepsis/metabolism , Sepsis/virology
15.
Eur Rev Med Pharmacol Sci ; 25(10): 3886-3897, 2021 May.
Article in English | MEDLINE | ID: covidwho-1264765

ABSTRACT

OBJECTIVE: Platelets, blood coagulation along with fibrinolysis are greatly involved in the pathophysiology of infectious diseases induced by bacteria, parasites and virus. This phenomenon is not surprising since both the innate immunity and the hemostatic systems are two ancestral mechanisms which closely cooperate favoring host's defense against foreign invaders. However, the excessive response of these systems may be dangerous for the host itself. MATERIALS AND METHODS: We searched and retrieved the articles, using the following electronic database: MedLine and Embase. We limited our search to articles published in English, but no restrictions in terms of article type, publication year, and geography were adopted. RESULTS: The hemostatic phenotype of the infectious diseases is variable depending on the points of attack of the different involved pathogens. Infectious diseases which show a prothrombotic phenotype are bacterial sepsis, SARS-CoV-2 and malaria. However, among the bacterial sepsis, Yersinia Pestis is characterized by a profibrinolytic behavior. On the contrary, the hemorrhagic fevers, due to Dengue and Ebola virus, mainly exploit the activation of fibrinolysis secondary to a huge endothelial damage which can release a large amount of t-PA in the early phase of the diseases. CONCLUSIONS: Blood coagulation and fibrinolysis are greatly activated based on the strategy of the different infectious agents which exploit the excess of response of both systems to achieve the greatest possible virulence.


Subject(s)
Blood Coagulation , COVID-19/pathology , Fibrinolysis , COVID-19/complications , COVID-19/virology , Endothelial Cells/cytology , Endothelial Cells/metabolism , Endothelial Cells/virology , Erythrocytes/cytology , Erythrocytes/metabolism , Erythrocytes/parasitology , Humans , Monocytes/cytology , Monocytes/metabolism , Monocytes/virology , SARS-CoV-2/isolation & purification , Thromboplastin/metabolism , Viruses/pathogenicity
16.
Transfus Apher Sci ; 60(5): 103188, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1263383

ABSTRACT

OBJECTIVES AND BACKGROUND: In December 2019, the first case of COVID-19 was reported in Wuhan, China. Its causative virus, is a novel strain of RNA viruses with high mortality rate. There is no definitive treatment, but among available approaches the use of recovered patients' plasma containing specific antibodies can enhance the immune response against coronavirus. However, the dearth of eligible donors and also ABO incompatibility in plasma transfusion, have limited this therapeutic method. Therefore, it is highly desirable to introduce a simple procedure that allows efficient reduction or even removal of natural ABO antibodies. Accordingly, we aimed to evaluate a RBC-mediated adsorption technique that reduces the titer of the mentioned antibodies in plasma. METHODS/MATERIALS: This experimental study was conducted in Kerman University of Medical Sciences, Kerman, Iran. The pre- and post-incubation antibody titers of 168 plasma samples were determined. For incubation, each plasma sample was exposed (60 min) to different percentages of RBCs at room temperature or 4 °C. RESULTS: The results evidenced that both the concentration of RBCs and temperature had significant decreasing effects on antibody titer (P < 0.001) and all concentrations significantly reduced titer. Compared to RT, 4 °C further reduced the antibody titer. Overall, the best incubation condition for reducing antibody titer in all blood groups was 4 °C and 2% RBCs concentration. CONCLUSION: The presented adsorption procedure is able to produce universal plasma (we call it Ubiquitous Convalescent Plasma) with a non-immunogenic level of ABO mismatch antibodies which can be used for COVID-19 patients with any type of blood group with desirable simplicity, feasibility, and efficacy.


Subject(s)
COVID-19/therapy , Immunosorbent Techniques , Isoantibodies/blood , Plasma , SARS-CoV-2 , ABO Blood-Group System/immunology , Adsorption , Blood Group Antigens , COVID-19/blood , Cold Temperature , Convalescence , Erythrocyte Count , Erythrocytes/immunology , Humans , Immunization, Passive/methods , Isoantibodies/immunology
18.
Immunobiology ; 226(3): 152093, 2021 05.
Article in English | MEDLINE | ID: covidwho-1237723

ABSTRACT

In order to study the mechanisms of COVID-19 damage following the complement activation phase occurring during the innate immune response to SARS-CoV-2, CR1 (the regulating complement activation factor, CD35, the C3b/C4b receptor), C4d deposits on Erythrocytes (E), and the products of complement activation C3b/C3bi, were assessed in 52 COVID-19 patients undergoing O2 therapy or assisted ventilation in ICU units in Rheims France. An acquired decrease of CR1 density on E from COVID-19 patients was observed (Mean = 418, SD = 162, N = 52) versus healthy individuals (Mean = 592, SD = 287, N = 400), Student's t-test p < 10-6, particularly among fatal cases, and in parallel with several parameters of clinical severity. Large deposits of C4d on E in patients were well above values observed in normal individuals, mostly without concomitant C3 deposits, in more than 80% of the patients. This finding is reminiscent of the increased C4d deposits on E previously observed to correlate with sub endothelial pericapillary deposits in organ transplant rejection, and with clinical SLE flares. Conversely, significant C3 deposits on E were only observed among » of the patients. The decrease of CR1/E density, deposits of C4 fragments on E and previously reported detection of virus spikes or C3 on E among COVID-19 patients, suggest that the handling and clearance of immune complex or complement fragment coated cell debris may play an important role in the pathophysiology of SARS-CoV-2. Measurement of C4d deposits on E might represent a surrogate marker for assessing inflammation and complement activation occurring in organ capillaries and CR1/E decrease might represent a cumulative index of complement activation in COVID-19 patients. Taken together, these original findings highlight the participation of complement regulatory proteins and indicate that E are important in immune pathophysiology of COVID-19 patients. Besides a potential role for monitoring the course of disease, these observations suggest that novel therapies such as the use of CR1, or CR1-like molecules, in order to down regulate complement activation and inflammation, should be considered.


Subject(s)
Antigen-Antibody Complex/metabolism , COVID-19/immunology , Complement C4b/metabolism , Erythrocytes/metabolism , Peptide Fragments/metabolism , Receptors, Complement 3b/metabolism , SARS-CoV-2/physiology , COVID-19/therapy , Complement Activation , Erythrocytes/pathology , France , Gene Expression Regulation , Humans , Intensive Care Units , Receptors, Complement 3b/genetics , Receptors, Complement 3b/therapeutic use
19.
Crit Care Med ; 49(4): 661-670, 2021 04 01.
Article in English | MEDLINE | ID: covidwho-1238251

ABSTRACT

OBJECTIVES: In this study, we hypothesized that coronavirus disease 2019 patients exhibit sublingual microcirculatory alterations caused by inflammation, coagulopathy, and hypoxemia. DESIGN: Multicenter case-controlled study. SETTING: Two ICUs in The Netherlands and one in Switzerland. PATIENTS: Thirty-four critically ill coronavirus disease 2019 patients were compared with 33 healthy volunteers. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The microcirculatory parameters quantified included total vessel density (mm × mm-2), functional capillary density (mm × mm-2), proportion of perfused vessels (%), capillary hematocrit (%), the ratio of capillary hematocrit to systemic hematocrit, and capillary RBC velocity (µm × s-1). The number of leukocytes in capillary-postcapillary venule units per 4-second image sequence (4 s-1) and capillary RBC microaggregates (4 s-1) was measured. In comparison with healthy volunteers, the microcirculation of coronavirus disease 2019 patients showed increases in total vessel density (22.8 ± sd 5.1 vs 19.9 ± 3.3; p < 0.0001) and functional capillary density (22.2 ± 4.8 vs 18.8 ± 3.1; p < 0.002), proportion of perfused vessel (97.6 ± 2.1 vs 94.6 ± 6.5; p < 0.01), RBC velocity (362 ± 48 vs 306 ± 53; p < 0.0001), capillary hematocrit (5.3 ± 1.3 vs 4.7 ± 0.8; p < 0.01), and capillary-hematocrit-to-systemic-hematocrit ratio (0.18 ± 0.0 vs 0.11 ± 0.0; p < 0.0001). These effects were present in coronavirus disease 2019 patients with Sequential Organ Failure Assessment scores less than 10 but not in patients with Sequential Organ Failure Assessment scores greater than or equal to 10. The numbers of leukocytes (17.6 ± 6.7 vs 5.2 ± 2.3; p < 0.0001) and RBC microaggregates (0.90 ± 1.12 vs 0.06 ± 0.24; p < 0.0001) was higher in the microcirculation of the coronavirus disease 2019 patients. Receiver-operating-characteristics analysis of the microcirculatory parameters identified the number of microcirculatory leukocytes and the capillary-hematocrit-to-systemic-hematocrit ratio as the most sensitive parameters distinguishing coronavirus disease 2019 patients from healthy volunteers. CONCLUSIONS: The response of the microcirculation to coronavirus disease 2019-induced hypoxemia seems to be to increase its oxygen-extraction capacity by increasing RBC availability. Inflammation and hypercoagulation are apparent in the microcirculation by increased numbers of leukocytes and RBC microaggregates.


Subject(s)
COVID-19/mortality , Capillaries , Hypoxia/etiology , Leukocytes , Microcirculation/physiology , Erythrocytes , Female , Humans , Male , Middle Aged
20.
Opt Lett ; 46(10): 2344-2347, 2021 May 15.
Article in English | MEDLINE | ID: covidwho-1229026

ABSTRACT

Rapid screening of red blood cells for active infection of COVID-19 is presented using a compact and field-portable, 3D-printed shearing digital holographic microscope. Video holograms of thin blood smears are recorded, individual red blood cells are segmented for feature extraction, then a bi-directional long short-term memory network is used to classify between healthy and COVID positive red blood cells based on their spatiotemporal behavior. Individuals are then classified based on the simple majority of their cells' classifications. The proposed system may be beneficial for under-resourced healthcare systems. To the best of our knowledge, this is the first report of digital holographic microscopy for rapid screening of COVID-19.


Subject(s)
COVID-19 Testing/methods , COVID-19/blood , Deep Learning , Erythrocytes/pathology , Holography/instrumentation , SARS-CoV-2 , COVID-19/classification , Humans , Image Enhancement/instrumentation , Microscopy/instrumentation , Reproducibility of Results , Sensitivity and Specificity
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