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1.
Ann Med ; 54(1): 3189-3200, 2022 12.
Статья в английский | MEDLINE | ID: covidwho-2106905

Реферат

INTRODUCTION: In order to identify therapeutic targets in Coronavirus disease 2019 (COVID-19), it is important to identify molecules involved in the biological responses that are modulated in COVID-19. Lysophosphatidic acids (LPAs) are involved in the pulmonary inflammation and fibrosis are one of the candidate molecules. The aim of this study was to evaluate the association between the serum levels of autotaxin (ATX), which are enzymes involved in the synthesis of lysophosphatidic acids. MATERIAL AND METHODS: We enrolled 134 subjects with COVID-19 and 58 normal healthy subjects for the study. We measured serum ATX levels longitudinally in COVID-19 patients and investigated the time course and the association with severity and clinical parameters. RESULTS: The serum ATX levels were reduced in all patients with COVID-19, irrespective of the disease severity, and were negatively associated with the serum CRP, D-dimer, and anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody levels. DISCUSSION: Considering the biological properties of LPAs in the pulmonary inflammation and fibrosis, modulation of ATX might be compensatory biological responses to suppress immunological overreaction especially in the lung, which is an important underlying mechanism for the mortality of the disease. CONCLUSIONS: COVID-19 patients showed a decrease in the serum levels of ATX, irrespective of the disease severity. Key MessagesAutotaxin (ATX) is an enzyme involved in the synthesis of lysophosphatidic acid (LPA), which has been reported to be involved in pulmonary inflammation and fibrosis. Patients with COVID-19 show decrease in the serum levels of ATX. Modulation of ATX might be compensatory biological responses to suppress immunological overreaction.


Тема - темы
COVID-19 , Phosphoric Diester Hydrolases , Humans , COVID-19/blood , Fibrosis , Lung , Lysophospholipids , Phosphoric Diester Hydrolases/blood , SARS-CoV-2
2.
Cell Rep ; 41(8): 111708, 2022 Nov 22.
Статья в английский | MEDLINE | ID: covidwho-2095146

Реферат

Genome-wide association studies (GWASs) show that genetic factors contribute to the risk of severe coronavirus disease 2019 (COVID-19) and blood analyte levels. Here, we utilize GWAS summary statistics to study the shared genetic influences (pleiotropy) between severe COVID-19 and 344 blood analytes at the genome, gene, and single-nucleotide polymorphism (SNP) levels. Our pleiotropy analyses genetically link blood levels of 71 analytes to severe COVID-19 in at least one of the three levels of investigation-suggesting shared biological mechanisms or causal relationships. Six analytes (alanine aminotransferase, alkaline phosphatase, apolipoprotein B, C-reactive protein, triglycerides, and urate) display evidence of pleiotropy with severe COVID-19 at all three levels. Causality analyses indicate that higher triglycerides levels causally increase the risk of severe COVID-19, thereby providing important support for the use of lipid-lowering drugs such as statins and fibrates to prevent severe COVID-19.


Тема - темы
COVID-19 , Humans , COVID-19/blood , COVID-19/genetics , Genome-Wide Association Study , Polymorphism, Single Nucleotide , Triglycerides/blood , Risk Factors
3.
Iran J Immunol ; 18(1): 47-53, 2021 03.
Статья в английский | MEDLINE | ID: covidwho-2091347

Реферат

BACKGROUND: Incidence and severity of SARS-CoV2 infection are significantly lower in children and teenagers proposing that certain vaccines, routinely administered to neonates and children may provide cross-protection against this emerging infection. OBJECTIVE: To assess the cross-protection induced by prior measles, mumps and rubella (MMR) vaccinations against COVID-19. METHODS: The antibody responses to MMR and tetanus vaccines were determined in 53 patients affected with SARS-CoV2 infection and 52 age-matched healthy subjects. Serum levels of antibodies specific for NP and RBD of SARS-CoV2 were also determined in both groups of subjects with ELISA. RESULTS: Our results revealed significant differences in anti-NP (P<0.0001) and anti-RBD (P<0.0001) IgG levels between patients and healthy controls. While the levels of rubella- and mumps specific IgG were not different in the two groups of subjects, measles-specific IgG was significantly higher in patients (P<0.01). The serum titer of anti-tetanus antibody, however, was significantly lower in patients compared to healthy individuals (P<0.01). CONCLUSION: Our findings suggest that measles vaccination triggers those B cells cross-reactive with SARS-CoV2 antigens leading to the production of increased levels of measles-specific antibody.


Тема - темы
Antibodies, Viral/blood , Antigens, Viral/immunology , COVID-19/immunology , Immunization , Immunoglobulin G/blood , Measles-Mumps-Rubella Vaccine/therapeutic use , SARS-CoV-2/immunology , Age Factors , Aged , B-Lymphocytes/immunology , B-Lymphocytes/virology , Biomarkers/blood , COVID-19/blood , COVID-19/diagnosis , COVID-19/virology , Case-Control Studies , Cross Protection , Cross Reactions , Female , Host-Pathogen Interactions , Humans , Male , Measles-Mumps-Rubella Vaccine/immunology , Middle Aged , Tetanus Toxoid/immunology , Tetanus Toxoid/therapeutic use
4.
Vox Sang ; 116(2): 155-166, 2021 Feb.
Статья в английский | MEDLINE | ID: covidwho-2078680

Реферат

BACKGROUND AND OBJECTIVE: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a novel coronavirus, first identified in China at the end of 2019 and has now caused a worldwide pandemic. In this review, we provide an overview of the implications of SARS-CoV-2 for blood safety and sufficiency. MATERIAL AND METHOD: We searched the PubMed database, the preprint sites bioRxiv and medRxiv, the websites of the World Health Organization, European Centre for Disease Prevention and Control, the US Communicable Diseases Center and monitored ProMed updates. RESULTS: An estimated 15%-46% of SARS-CoV-2 infections are asymptomatic. The reported mean incubation period is 3 to 7 days with a range of 1-14 days. The blood phase of SARS-CoV-2 appears to be brief and low level, with RNAaemia detectable in only a small proportion of patients, typically associated with more severe disease and not demonstrated to be infectious virus. An asymptomatic blood phase has not been demonstrated. Given these characteristics of SARS-CoV-2 infection and the absence of reported transfusion transmission (TT), the TT risk is currently theoretical. To mitigate any potential TT risk, but more importantly to prevent respiratory transmission in donor centres, blood centres can implement donor deferral policies based on travel, disease status or potential risk of exposure. CONCLUSION: The TT risk of SARS-CoV-2 appears to be low. The biggest risk to blood services in the current COVID-19 pandemic is to maintain the sufficiency of the blood supply while minimizing respiratory transmission of SARS-CoV-19 to donors and staff while donating blood.


Тема - темы
Blood Safety , COVID-19/blood , COVID-19/prevention & control , COVID-19/virology , Transfusion Reaction/prevention & control , Blood Transfusion , Geography , Humans , RNA, Viral/analysis , Risk Assessment , SARS-CoV-2 , Safety Management , World Health Organization
5.
J Leukoc Biol ; 112(1): 201-212, 2022 07.
Статья в английский | MEDLINE | ID: covidwho-2075041

Реферат

T cells are thought to be an important correlates of protection against SARS-CoV2 infection. However, the composition of T cell subsets in convalescent individuals of SARS-CoV2 infection has not been well studied. The authors determined the lymphocyte absolute counts, the frequency of memory T cell subsets, and the plasma levels of common γ-chain in 7 groups of COVID-19 individuals, based on days since RT-PCR confirmation of SARS-CoV-2 infection. The data show that both absolute counts and frequencies of lymphocytes as well as, the frequencies of CD4+ central and effector memory cells increased, and the frequencies of CD4+ naïve T cells, transitional memory, stem cell memory T cells, and regulatory cells decreased from Days 15-30 to Days 61-90 and plateaued thereafter. In addition, the frequencies of CD8+ central memory, effector, and terminal effector memory T cells increased, and the frequencies of CD8+ naïve cells, transitional memory, and stem cell memory T cells decreased from Days 15-30 to Days 61-90 and plateaued thereafter. The plasma levels of IL-2, IL-7, IL-15, and IL-21-common γc cytokines started decreasing from Days 15-30 till Days 151-180. Severe COVID-19 patients exhibit decreased levels of lymphocyte counts and frequencies, higher frequencies of naïve cells, regulatory T cells, lower frequencies of central memory, effector memory, and stem cell memory, and elevated plasma levels of IL-2, IL-7, IL-15, and IL-21. Finally, there was a significant correlation between memory T cell subsets and common γc cytokines. Thus, the study provides evidence of alterations in lymphocyte counts, memory T cell subset frequencies, and common γ-chain cytokines in convalescent COVID-19 individuals.


Тема - темы
COVID-19 , Cytokines , Memory T Cells , CD4-Positive T-Lymphocytes , CD8-Positive T-Lymphocytes , COVID-19/blood , COVID-19/immunology , Convalescence , Cytokines/blood , Humans , Immunologic Memory/immunology , Interleukin-15/blood , Interleukin-2/blood , Interleukin-7/blood , Memory T Cells/immunology , RNA, Viral , SARS-CoV-2 , T-Lymphocyte Subsets/immunology
6.
Niger J Clin Pract ; 25(9): 1418-1423, 2022 Sep.
Статья в английский | MEDLINE | ID: covidwho-2055768

Реферат

Background: In coronavirus disease 2019 (COVID-19) caused by SARSCoV2 viruses, coagulation abnormalities are strongly correlated between disease severity and mortality risk. Aims: The aim was to search for new indices to determine mortality risk. Fibrinogen times D-dimer to albumin times platelet ratio calculated with the formula (FDAPR index: ((Fibrinogen × D-dimer)/(Albumin × Platelet)) investigated as a mortality marker in COVID-19 patients. The hospitalization data of 1124 patients were analyzed from the electronic archive system. Hemogram, coagulation, and inflammatory markers were investigated in the study group. Materials and Methods: All statistical analyses like the student t-test, Mann-Whitney U, Kaplan-Meier, and Cox hazard ratio, were performed with the SPSS 22.0 program. Results: Prothrombin time was prolonged significantly in patients (P < 0.05) compared to healthy subjects (n = 30). D-dimer and fibrinogen were high, and albumin and platelet counts were low in COVID-19 patients (all, P < 0.001). When the data of 224 non-survivors and 900 survived patients were compared, D-dimer and fibrinogen were higher, and albumin and platelet lower (all, P < 0.001) compared to mild and severe patients. At the cut-off value of 0.49, the FDAPR index was performed with 89.1% sensitivity and 88.6% specificity. FDAPR index had the highest mortality predictive power (P < 0.01; HR = 5.366; 95% CI; 1.729-16.654). Conclusions: This study revealed that the FDAPR index could be used as a mortality marker of COVID-19 disease.


Тема - темы
COVID-19 , Albumins , Biomarkers/blood , COVID-19/blood , COVID-19/mortality , Fibrin Fibrinogen Degradation Products , Fibrinogen , Humans , Retrospective Studies , SARS-CoV-2
7.
Thorac Cancer ; 13(22): 3200-3207, 2022 Nov.
Статья в английский | MEDLINE | ID: covidwho-2052169

Реферат

BACKGROUND: The correlation between COVID-19 and RT has not been determined to date and remains a clinical question. The aim of this study was to evaluate coronavirus disease 2019 (COVID-19) pneumonia before, during, and after radiation therapy (RT) regarding the radiation doses, radiation pneumonitis, and surfactant protein levels. METHODS: We evaluated patients diagnosed with COVID-19 before, during, or after RT for the lung between August 2020 and April 2022. In patients with breast cancer, the RT dose to the ipsilateral lung was determined. In all other patients, bilateral lung RT doses were determined. Patients diagnosed with COVID-19 after RT were evaluated to determine whether radiation pneumonitis had worsened compared with before RT. The serum levels of the surfactant proteins SP-A and SP-D were measured before, during, and after RT. RESULTS: The patients included in the study comprised three men (27.3%) and eight women (72.7%). The primary cancer sites were the breast (n = 7; 63.7%), lung (n = 2; 18.1%), esophagus (n = 1; 9.1%), and tongue (9.1%). COVID-19 was diagnosed before RT in four patients, during RT in two patients, and after RT in five patients. Six (54.5%) patients developed COVID-19 pneumonia. Radiation pneumonitis grade ≥2 was not identified in any patient, and radiation pneumonitis did not worsen after RT in any patient. No rapid increases or decreases in SP-A and SP-D levels occurred after the diagnosis of COVID-19 in all patients regardless of RT timing. CONCLUSIONS: COVID-19 did not appear to result in lung toxicity and surfactant protein levels did not change dramatically.


Тема - темы
COVID-19 , Lung , Pulmonary Surfactant-Associated Protein A , Pulmonary Surfactant-Associated Protein D , Radiation Pneumonitis , Female , Humans , Male , COVID-19/blood , COVID-19/epidemiology , Lung/radiation effects , Lung Neoplasms/radiotherapy , Lung Neoplasms/drug therapy , Pulmonary Surfactant-Associated Protein D/blood , Radiation Pneumonitis/epidemiology , Pulmonary Surfactant-Associated Protein A/blood , Breast Neoplasms/radiotherapy
8.
Proteomics Clin Appl ; 16(6): e2100100, 2022 Nov.
Статья в английский | MEDLINE | ID: covidwho-2047908

Реферат

PURPOSE: Acute phase reactants (APRs) play a critical role in inflammation. The difference in their physiological functions or the different dynamic ranges of these proteins in plasma makes it difficult to detect them simultaneously and to use several of these proteins as a tool in clinical practice. EXPERIMENTAL DESIGN: A novel multiplex assay has been designed and optimized to carry out a high-throughput and simultaneous screening of APRs, allowing the detection of each of them at the same time and in their corresponding dynamic range. RESULTS: Using Sars-CoV-2 infection as a model, it has been possible to profile different patterns of acute phase proteins that vary significantly between healthy and infected patients. In addition, severity profiles (acute respiratory distress syndrome and sepsis) have been established. CONCLUSIONS AND CLINICAL RELEVANCE: Differential profiles in acute phase proteins can serve as a diagnostic and prognostic tool, among patient stratification. The design of this new platform for their simultaneous detection paves the way for them to be more extensive use in clinical practice.


Тема - темы
Acute-Phase Proteins , Acute-Phase Reaction , COVID-19 , SARS-CoV-2 , Humans , Acute-Phase Proteins/analysis , COVID-19/blood , COVID-19/diagnosis , Proteomics , Acute-Phase Reaction/blood , Acute-Phase Reaction/diagnosis , Acute-Phase Reaction/virology
9.
MEDICC Rev ; 24(3-4): 53-56, 2022 Oct 31.
Статья в английский | MEDLINE | ID: covidwho-2026732

Реферат

INTRODUCTION: Bile acids are signaling molecules with immune, metabolic and intestinal microbiota control actions. In high serum concentrations they increase inflammatory response from the liver-gut axis, until causing multiorgan failure and death; therefore, they may be associated with COVID-19's clinical progression, as a consequence of tissue and metabolic damage caused by SARS-CoV-2. While this topic is of considerable clinical interest, to our knowledge, it has not been studied in Cuba. OBJECTIVE: Study and preliminarily characterize patients admitted with a diagnosis of COVID-19 and high levels of serum bile acids. METHODS: A preliminary exploratory study was carried out with descriptive statistical techniques in 28 COVID-19 patients (17 women, 11 men; aged 19-92 years) who exhibited high levels of serum bile acids (≥10.1 µmol/L) on admission to the Dr. Luis Díaz Soto Central Military Hospital in Havana, Cuba, from September through November 2021. RESULTS: On admission patients presented hypocholesterolemia (13/28; 46.4%), hyperglycemia (12/28; 43.0%) and hyper gamma-glutamyl transpeptidase (23/28; 84.2%). Median blood glucose (5.8 mmol/L) and cholesterol (4.1 mmol/L) were within normal ranges (3.2‒6.2 mmol/L and 3.9‒5.2 mmol/L, respectively). Severe or critical stage was the most frequent (13/28) and median serum bile acids (31.6 µmol/L) and gamma-glutamyl transferase (108.6 U/L) averaged well above their respective normal ranges (serum bile acids: 0‒10 µmol/L; GGT: 9‒36 U/L). Arterial hypertension was the most frequent comorbidity (19/28; 67.9%). CONCLUSIONS: Severe or critical stage predominated, with serum bile acids and gamma-glutamyl transferase blood levels above normal ranges. The study suggests that serum bile acid is toxic at levels ≥10.1 µmol/L, and at such levels is involved in the inflammatory process and in progression to severe and critical clinical stages of the disease. In turn, this indicates the importance of monitoring bile acid homeostasis in hospitalized COVID-19 patients and including control of its toxicity in treatment protocols.


Тема - темы
Bile Acids and Salts , COVID-19 , Female , Humans , Male , Bile Acids and Salts/blood , COVID-19/blood , COVID-19/diagnosis , Cuba/epidemiology , Hospitals , SARS-CoV-2 , Transferases , Young Adult , Adult , Middle Aged , Aged , Aged, 80 and over
10.
Front Immunol ; 13: 946522, 2022.
Статья в английский | MEDLINE | ID: covidwho-2022727

Реферат

Numerous publications have underlined the link between complement C5a and the clinical course of COVID-19. We previously reported that levels of C5a remain high in the group of severely ill patients up to 90 days after hospital discharge. We have now evaluated which complement pathway fuels the elevated levels of C5a during hospitalization and follow-up. The alternative pathway (AP) activation marker C3bBbP and the soluble fraction of C4d, a footprint of the classical/lectin (CP/LP) pathway, were assessed by immunoenzymatic assay in a total of 188 serial samples from 49 patients infected with SARS-CoV-2. Unlike C5a, neither C3bBbP nor C4d readouts rose proportionally to the severity of the disease. Detailed correlation analyses in hospitalization and follow-up samples collected from patients of different disease severity showed significant positive correlations of AP and CP/LP markers with C5a in certain groups, except for the follow-up samples of the patients who suffered from highly severe COVID-19 and presented the highest C5a readouts. In conclusion, there is not a clear link between persistently high levels of C5a after hospital discharge and markers of upstream complement activation, suggesting the existence of a non-canonical source of C5a in patients with a severe course of COVID-19.


Тема - темы
COVID-19 , Complement Activation , Complement C3b , Complement C4b , Complement C5a , Complement Factor B , Peptide Fragments , Biomarkers/blood , COVID-19/blood , COVID-19/immunology , Complement Activation/immunology , Complement C3b/immunology , Complement C4b/immunology , Complement C5a/analysis , Complement C5a/immunology , Complement Factor B/immunology , Complement System Proteins/immunology , Humans , Peptide Fragments/immunology , SARS-CoV-2
11.
Allergy Asthma Proc ; 43(5): 419-430, 2022 Sep 01.
Статья в английский | MEDLINE | ID: covidwho-2022489

Реферат

Background: Secretory immunoglobulin A (sIgA) plays an important role in antiviral protective immunity. Although salivary testing has been used for many viral infections, including severe acute respiratory syndrome (SARS) and Middle East Respiratory Syndrome (MERS), its use has not yet been well established with the SARS coronavirus 2 (SARS-CoV-2). Quantification of salivary IgA and IgG antibodies can elucidate mucosal and systemic immune responses after natural infection or vaccination. Here, we report the development and validation of a rapid enzyme-linked immunosorbent assay (ELISA) for anti-SARS-CoV-2 salivary IgA and serum IgG antibodies, and present quantitative results for immunized subjects both prior to or following COVID-19 infections. Objective: Total and serum SARS-CoV-2 spike-specific IgG responses were compared with salivary spike-specific IgA and IgG responses in samples obtained from patients recently infected with SARS-CoV-2 and from subjects recently immunized with COVID-19 vaccines. Methods: A total of 52 paired saliva and serum samples were collected from 26 study participants: 7 subjects after COVID-19 infection and 19 subjects who were uninfected. The ELISA results from these samples were compared with five prepandemic control serum samples. Total IgG and SARS-CoV-2 spike-specific IgG in the serum samples from the subjects who were infected and vaccinated were also measured in a commercial laboratory with an enzyme immunoassay. Results: A wide variation in antibody responses was seen in salivary and serum samples measured by both methods. Three groups of serum total and IgG spike-specific SARS-CoV-2 antibody responses were observed: (1) low, (2) intermediate, and (3) high antibody responders. A correlational analysis of salivary IgA (sIgA) responses with serum IgG concentrations showed a statistical correlation in the low and intermediate antibody responder groups but not in the high group (which we believe was a result of saturation). Conclusion: These preliminary findings suggest measuring salivary and serum IgG and IgA merit further investigation as markers of current or recent SARS-CoV-2 infections.


Тема - темы
COVID-19 Vaccines , COVID-19 , Immunoglobulin A , Immunoglobulin G , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Antibodies, Viral , COVID-19/blood , COVID-19/immunology , COVID-19/prevention & control , COVID-19 Vaccines/immunology , Humans , Immunization , Immunoglobulin A/analysis , Immunoglobulin A/blood , Immunoglobulin A/immunology , Immunoglobulin A, Secretory , Immunoglobulin G/analysis , Immunoglobulin G/blood , Immunoglobulin G/immunology , Saliva/chemistry , Saliva/immunology , Spike Glycoprotein, Coronavirus/immunology , Vaccination
12.
Biophys J ; 121(18): 3309-3319, 2022 09 20.
Статья в английский | MEDLINE | ID: covidwho-2003901

Реферат

Microthrombi and circulating cell clusters are common microscopic findings in patients with coronavirus disease 2019 (COVID-19) at different stages in the disease course, implying that they may function as the primary drivers in disease progression. Inspired by a recent flow imaging cytometry study of the blood samples from patients with COVID-19, we perform computational simulations to investigate the dynamics of different types of circulating cell clusters, namely white blood cell (WBC) clusters, platelet clusters, and red blood cell clusters, over a range of shear flows and quantify their impact on the viscosity of the blood. Our simulation results indicate that the increased level of fibrinogen in patients with COVID-19 can promote the formation of red blood cell clusters at relatively low shear rates, thereby elevating the blood viscosity, a mechanism that also leads to an increase in viscosity in other blood diseases, such as sickle cell disease and type 2 diabetes mellitus. We further discover that the presence of WBC clusters could also aggravate the abnormalities of local blood rheology. In particular, the extent of elevation of the local blood viscosity is enlarged as the size of the WBC clusters grows. On the other hand, the impact of platelet clusters on the local rheology is found to be negligible, which is likely due to the smaller size of the platelets. The difference in the impact of WBC and platelet clusters on local hemorheology provides a compelling explanation for the clinical finding that the number of WBC clusters is significantly correlated with thrombotic events in COVID-19 whereas platelet clusters are not. Overall, our study demonstrates that our computational models based on dissipative particle dynamics can serve as a powerful tool to conduct quantitative investigation of the mechanism causing the pathological alterations of hemorheology and explore their connections to the clinical manifestations in COVID-19.


Тема - темы
COVID-19 , Blood Viscosity , COVID-19/blood , Fibrinogen/metabolism , Hemorheology , Humans
14.
Science ; 377(6608): 803, 2022 08 19.
Статья в английский | MEDLINE | ID: covidwho-1992931

Реферат

Study implicates lack of key hormone, battle-weary immune cells, and awakened viruses.


Тема - темы
COVID-19 , COVID-19/blood , COVID-19/immunology , Humans , Hydrocortisone/blood , T-Lymphocytes/immunology
15.
Proc Natl Acad Sci U S A ; 119(30): e2203659119, 2022 07 26.
Статья в английский | MEDLINE | ID: covidwho-1991766

Реферат

This study analyzed whole blood samples (n = 56) retrieved from 30 patients at 1 to 21 (median 9) mo after verified COVID-19 to determine the polarity and duration of antigen-specific T cell reactivity against severe acute respiratory syndrome coronavirus 2-derived antigens. Multimeric peptides spanning the entire nucleocapsid protein triggered strikingly synchronous formation of interleukin (IL)-4, IL-12, IL-13, and IL-17 ex vivo until ∼70 d after confirmed infection, whereafter this reactivity was no longer inducible. In contrast, levels of nucleocapsid-induced IL-2 and interferon-γ remained stable and highly correlated at 3 to 21 mo after infection. Similar cytokine dynamics were observed in unvaccinated, convalescent patients using whole-blood samples stimulated with peptides spanning the N-terminal portion of the spike 1 protein. These results unravel two phases of T cell reactivity following natural COVID-19: an early, synchronous response indicating transient presence of multipolar, antigen-specific T helper (TH) cells followed by an equally synchronous and durable TH1-like reactivity reflecting long-lasting T cell memory.


Тема - темы
COVID-19 , Cytokines , SARS-CoV-2 , T-Lymphocytes, Helper-Inducer , Antibodies, Viral/blood , Antigens, Viral/immunology , COVID-19/blood , COVID-19/immunology , Convalescence , Cytokines/blood , Humans , Interferon-gamma/blood , Nucleocapsid Proteins/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , T-Lymphocytes, Helper-Inducer/immunology
16.
Proc Natl Acad Sci U S A ; 119(34): e2117089119, 2022 08 23.
Статья в английский | MEDLINE | ID: covidwho-1984597

Реферат

The COVID-19 pandemic has incurred tremendous costs worldwide and is still threatening public health in the "new normal." The association between neutralizing antibody levels and metabolic alterations in convalescent patients with COVID-19 is still poorly understood. In the present work, we conducted absolutely quantitative profiling to compare the plasma cytokines and metabolome of ordinary convalescent patients with antibodies (CA), convalescents with rapidly faded antibodies (CO), and healthy subjects. As a result, we identified that cytokines such as M-CSF and IL-12p40 and plasma metabolites such as glycylproline (gly-pro) and long-chain acylcarnitines could be associated with antibody fading in COVID-19 convalescent patients. Following feature selection, we built machine-learning-based classification models using 17 features (six cytokines and 11 metabolites). Overall accuracies of more than 90% were attained in at least six machine-learning models. Of note, the dipeptide gly-pro, a product of enzymatic peptide cleavage catalyzed by dipeptidyl peptidase 4 (DPP4), strongly accumulated in CO individuals compared with the CA group. Furthermore, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination experiments in healthy mice demonstrated that supplementation of gly-pro down-regulates SARS-CoV-2-specific receptor-binding domain antibody levels and suppresses immune responses, whereas the DPP4 inhibitor sitagliptin can counteract the inhibitory effects of gly-pro upon SARS-CoV-2 vaccination. Our findings not only reveal the important role of gly-pro in the immune responses to SARS-CoV-2 infection but also indicate a possible mechanism underlying the beneficial outcomes of treatment with DPP4 inhibitors in convalescent COVID-19 patients, shedding light on therapeutic and vaccination strategies against COVID-19.


Тема - темы
Antibodies, Neutralizing , Antibodies, Viral , COVID-19 , Convalescence , Cytokines , Dipeptides , Dipeptidyl-Peptidase IV Inhibitors , Animals , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , Antibody Formation , COVID-19/blood , COVID-19/drug therapy , COVID-19/immunology , Cytokines/blood , Dipeptides/blood , Dipeptidyl Peptidase 4/metabolism , Dipeptidyl-Peptidase IV Inhibitors/therapeutic use , Humans , Machine Learning , Metabolome , Mice , SARS-CoV-2 , Vaccination
17.
Nutrients ; 14(16)2022 Aug 10.
Статья в английский | MEDLINE | ID: covidwho-1979324

Реферат

BACKGROUND: Vitamin D deficiency has been associated with the severity of COVID-19. The role of vitamin D in pregnant women with COVID-19 has been poorly investigated to date. The aim of this study was to evaluate the influence of vitamin D in affecting some clinical features in pregnancy between SARS-CoV-2 positive and negative patients. METHODS: Vitamin D pathway related polymorphisms and 25-hydroxyvitamin D levels were quantified in pregnant women followed from the first to the third trimester of pregnancy. Vitamin D deficiency was considered with values ≤ 30 ng/mL. RESULTS: In total, 160 women were enrolled: 23 resulted positive for at least one SARS-CoV-2 related test (molecular swab or antibody tests). Vitamin D-associated polymorphisms were able to affect vitamin D levels in SARS-CoV-2 negative and positive subjects: remarkably, all the VDR TaqICC genotype patients were negative for SARS-CoV-2. In a sub-population (118 patients), vitamin D levels correlated with pregnancy-related factors, such as alpha-fetoprotein levels. Third-trimester vitamin D levels were lower in preterm births compared to full-term pregnancy: this trend was highlighted for SARS-CoV-2 positive patients. CONCLUSIONS: This is the first study demonstrating a role of vitamin D in affecting the clinical characteristics of pregnant women during the COVID-19 era. Further studies in larger and different cohorts of patients are required to confirm these findings.


Тема - темы
COVID-19 , Pregnancy , Premature Birth , Vitamin D Deficiency , Vitamin D , COVID-19/blood , COVID-19/complications , Female , Humans , Infant, Newborn , Pregnancy/blood , Premature Birth/blood , SARS-CoV-2 , Vitamin D/blood , Vitamin D Deficiency/blood , Vitamin D Deficiency/complications
18.
PLoS One ; 17(2): e0262591, 2022.
Статья в английский | MEDLINE | ID: covidwho-1968842

Реферат

SARS-CoV-2 Nucleocapsid (N) is the most abundant viral protein expressed in host samples and is an important antigen for diagnosis. N is a 45 kDa protein that does not present disulfide bonds. Intending to avoid non-specific binding of SARS-CoV-2 N to antibodies from patients who previously had different coronaviruses, a 35 kDa fragment of N was expressed without a conserved motif in E. coli as inclusion bodies (N122-419-IB). Culture media and IB washing conditions were chosen to obtain N122-419-IB with high yield (370 mg/L bacterial culture) and protein purity (90%). High pressure solubilizes protein aggregates by weakening hydrophobic and ionic interactions and alkaline pH promotes solubilization by electrostatic repulsion. The association of pH 9.0 and 2.4 kbar promoted efficient solubilization of N122-419-IB without loss of native-like tertiary structure that N presents in IB. N122-419 was refolded with a yield of 85% (326 mg/L culture) and 95% purity. The refolding process takes only 2 hours and the protein is ready for use after pH adjustment, avoiding the necessity of dialysis or purification. Antibody binding of COVID-19-positive patients sera to N122-419 was confirmed by Western blotting. ELISA using N122-419 is effective in distinguishing between sera presenting antibodies against SARS-CoV-2 from those who do not. To the best of our knowledge, the proposed condition for IB solubilization is one of the mildest described. It is possible that the refolding process can be extended to a wide range of proteins with high yields and purity, even those that are sensible to very alkaline pH.


Тема - темы
Antibodies, Viral/blood , Antigens, Viral/chemistry , COVID-19/blood , COVID-19/diagnosis , Coronavirus Nucleocapsid Proteins/chemistry , Immunoglobulin G/blood , Inclusion Bodies/chemistry , Protein Refolding , SARS-CoV-2/immunology , Antibodies, Viral/immunology , Antigens, Viral/immunology , COVID-19/virology , Coronavirus Nucleocapsid Proteins/immunology , Enzyme-Linked Immunosorbent Assay/methods , Escherichia coli/genetics , Escherichia coli/metabolism , Humans , Hydrogen-Ion Concentration , Hydrostatic Pressure , Immunoglobulin G/immunology , Phosphoproteins/chemistry , Phosphoproteins/immunology , Protein Structure, Tertiary , Recombinant Proteins/chemistry , Recombinant Proteins/immunology , Solubility
19.
Proc Natl Acad Sci U S A ; 119(33): e2203437119, 2022 08 16.
Статья в английский | MEDLINE | ID: covidwho-1960624

Реферат

The mortality of coronavirus disease 2019 (COVID-19) is strongly correlated with pulmonary vascular pathology accompanied by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection-triggered immune dysregulation and aberrant activation of platelets. We combined histological analyses using field emission scanning electron microscopy with energy-dispersive X-ray spectroscopy analyses of the lungs from autopsy samples and single-cell RNA sequencing of peripheral blood mononuclear cells to investigate the pathogenesis of vasculitis and immunothrombosis in COVID-19. We found that SARS-CoV-2 accumulated in the pulmonary vessels, causing exudative vasculitis accompanied by the emergence of thrombospondin-1-expressing noncanonical monocytes and the formation of myosin light chain 9 (Myl9)-containing microthrombi in the lung of COVID-19 patients with fatal disease. The amount of plasma Myl9 in COVID-19 was correlated with the clinical severity, and measuring plasma Myl9 together with other markers allowed us to predict the severity of the disease more accurately. This study provides detailed insight into the pathogenesis of vasculitis and immunothrombosis, which may lead to optimal medical treatment for COVID-19.


Тема - темы
COVID-19 , Lung , Myosin Light Chains , SARS-CoV-2 , Severity of Illness Index , Thromboinflammation , Vasculitis , COVID-19/blood , COVID-19/complications , COVID-19/pathology , Humans , Leukocytes, Mononuclear , Lung/blood supply , Lung/metabolism , Lung/pathology , Lung/virology , Myosin Light Chains/blood , RNA-Seq , SARS-CoV-2/isolation & purification , Single-Cell Analysis , Spectrometry, X-Ray Emission , Thromboinflammation/pathology , Thromboinflammation/virology , Vasculitis/pathology , Vasculitis/virology
20.
Pflugers Arch ; 474(10): 1069-1076, 2022 10.
Статья в английский | MEDLINE | ID: covidwho-1955965

Реферат

Proinflammatory cytokines target vascular endothelial cells during COVID-19 infections. In particular, the endothelial glycocalyx (eGC), a proteoglycan-rich layer on top of endothelial cells, was identified as a vulnerable, vasoprotective structure during infections. Thus, eGC damage can be seen as a hallmark in the development of endothelial dysfunction and inflammatory processes. Using sera derived from patients suffering from COVID-19, we could demonstrate that the eGC became progressively worse in relation to disease severity (mild vs severe course) and in correlation to IL-6 levels. This could be prevented by administering low doses of spironolactone, a well-known and highly specific aldosterone receptor antagonist. Our results confirm that SARS-CoV-2 infections cause eGC damage and endothelial dysfunction and we outline the underlying mechanisms and suggest potential therapeutic options.


Тема - темы
COVID-19 , Glycocalyx , Mineralocorticoid Receptor Antagonists , SARS-CoV-2 , Spironolactone , COVID-19/blood , COVID-19/drug therapy , COVID-19/pathology , Cytokines/pharmacology , Endothelial Cells/drug effects , Endothelial Cells/pathology , Glycocalyx/drug effects , Glycocalyx/pathology , Humans , Interleukin-6/blood , Mineralocorticoid Receptor Antagonists/pharmacology , Mineralocorticoid Receptor Antagonists/therapeutic use , Proteoglycans/analysis , Proteoglycans/blood , Spironolactone/pharmacology , Spironolactone/therapeutic use
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