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1.
Platelets ; 33(2): 200-207, 2022 Feb 17.
Article in English | MEDLINE | ID: covidwho-1788406

ABSTRACT

Evolving evidence demonstrates that platelets have major roles in viral syndromes through previously unrecognized viral sensing and effector functions. Activated platelets and increased platelet-leukocyte aggregates are observed in clinical and experimental viral infections. The mechanisms and outcomes of platelet-leukocyte interactions depend on the interacting leukocyte as well as on the pathogen and pathological conditions. In this review, we discuss the mechanisms involved in platelet interactions with leukocytes and its functions during viral infections. We focus on the contributions of human platelet-leukocyte interactions to pathophysiological and protective responses during viral infections of major global health relevance, including acquired immunodeficiency syndrome (AIDS), dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS), influenza pneumonia, and COVID-19.


Subject(s)
Blood Platelets/metabolism , Leukocytes/metabolism , Virus Diseases/blood , Humans
2.
J Vis Exp ; (181)2022 Mar 22.
Article in English | MEDLINE | ID: covidwho-1786126

ABSTRACT

White blood cell (WBC) is an important indicator of inflammation in the body, and it can help distinguish between bacterial and viral infections. At present, most primary medical institutions in China have a poor percentage of adoption of blood-testing technology, and a hematology detection system with a high price to performance ratio and easy operation is urgently needed in primary healthcare centers. This paper introduces the principle and operation procedures of a point-of-care testing (POCT) card-based leukocyte analyzer (evaluated system), which was used to detect WBC indexes such as neutrophils, lymphocytes, and intermediate group cells (including eosinophils, basophils, and monocytes) in whole blood. The results from the evaluated system were compared to those from two commercial automatic hematology analyzers (reference system). The correlation and consistency between the evaluated system and the commercial reference systems were analyzed. The results showed that WBC count and number of granulocytes detected by the evaluated and reference systems showed a strong positive correlation (rs = 0.972 and 0.973, respectively), while the number of lymphocytes showed a relatively low correlation (rs = 0.851). A Bland-Altman plot showed that the major difference between the values detected by the evaluated system and the reference systems is within 95% limits of agreement (LoA), indicating that the two systems are in good agreement. In conclusion, the evaluated system has an excellent correlation, robust consistency, and a reliable comparison with the results of the widely used automatic hematology analyzers. It is ideal for WBC detection in primary medical institutions where a full-automatic five-category hematology analyzer is unavailable, especially during the COVID-19 normalized prevention and control period.


Subject(s)
COVID-19 , Hematology , Humans , Leukocyte Count , Leukocytes , Point-of-Care Testing , Reproducibility of Results
3.
Front Immunol ; 13: 798712, 2022.
Article in English | MEDLINE | ID: covidwho-1779939

ABSTRACT

The immune system is a complex and sophisticated biological system, spanning multiple levels of complexity, from the molecular level to that of tissue. Our current understanding of its function and complexity, of the heterogeneity of leukocytes, is a result of decades of concentrated efforts to delineate cellular markers using conventional methods of antibody screening and antigen identification. In mammalian models, this led to in-depth understanding of individual leukocyte subsets, their phenotypes, and their roles in health and disease. The field was further propelled forward by the development of single-cell (sc) RNA-seq technologies, offering an even broader and more integrated view of how cells work together to generate a particular response. Consequently, the adoption of scRNA-seq revealed the unexpected plasticity and heterogeneity of leukocyte populations and shifted several long-standing paradigms of immunology. This review article highlights the unprecedented opportunities offered by scRNA-seq technology to unveil the individual contributions of leukocyte subsets and their crosstalk in generating the overall immune responses in bony fishes. Single-cell transcriptomics allow identifying unseen relationships, and formulating novel hypotheses tailored for teleost species, without the need to rely on the limited number of fish-specific antibodies and pre-selected markers. Several recent studies on single-cell transcriptomes of fish have already identified previously unnoticed expression signatures and provided astonishing insights into the diversity of teleost leukocytes and the evolution of vertebrate immunity. Without a doubt, scRNA-seq in tandem with bioinformatics tools and state-of-the-art methods, will facilitate studying the teleost immune system by not only defining key markers, but also teaching us about lymphoid tissue organization, development/differentiation, cell-cell interactions, antigen receptor repertoires, states of health and disease, all across time and space in fishes. These advances will invite more researchers to develop the tools necessary to explore the immunology of fishes, which remain non-conventional animal models from which we have much to learn.


Subject(s)
Fishes/genetics , Fishes/immunology , Leukocytes/immunology , Leukocytes/metabolism , RNA-Seq , Single-Cell Analysis , Animals , Immunity , Single-Cell Analysis/methods
4.
Clin Nucl Med ; 47(2): e177-e179, 2022 Feb 01.
Article in English | MEDLINE | ID: covidwho-1684920

ABSTRACT

ABSTRACT: Occurrence of invasive fungal infections has gained significant attention during recent times in patients with COVID-19. Patients with severe form of COVID-19, such as those treated in the intensive care unit with prolonged steroid use, are particularly vulnerable to secondary bacterial and fungal infections. Disseminated systemic mycosis is a life-threatening condition, especially in immunocompromised patients. Here, we report a case of a recovered severe COVID-19 patient, who presented with persistent fever. 18F-FDG-labeled leukocyte scan revealed focal accumulation of radiotracer in the small intestine and right lung lower lobe. Subsequently, performed biopsy revealed mucormycosis.


Subject(s)
COVID-19 , Invasive Fungal Infections , Fluorodeoxyglucose F18 , Humans , Leukocytes , Positron Emission Tomography Computed Tomography , SARS-CoV-2
5.
Cell Death Dis ; 13(2): 137, 2022 02 10.
Article in English | MEDLINE | ID: covidwho-1683990

ABSTRACT

Acute respiratory distress syndrome (ARDS) is triggered by various aetiological factors such as trauma, sepsis and respiratory viruses including SARS-CoV-2 and influenza A virus. Immune profiling of severe COVID-19 patients has identified a complex pattern of cytokines including granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin (IL)-5, which are significant mediators of viral-induced hyperinflammation. This strong response has prompted the development of therapies that block GM-CSF and other cytokines individually to limit inflammation related pathology. The common cytokine binding site of the human common beta (ßc) receptor signals for three inflammatory cytokines: GM-CSF, IL-5 and IL-3. In this study, ßc was targeted with the monoclonal antibody (mAb) CSL311 in engineered mice devoid of mouse ßc and ßIL-3 and expressing human ßc (hßcTg mice). Direct pulmonary administration of lipopolysaccharide (LPS) caused ARDS-like lung injury, and CSL311 markedly reduced lung inflammation and oedema, resulting in improved oxygen saturation levels in hßcTg mice. In a separate model, influenza (HKx31) lung infection caused viral pneumonia associated with a large influx of myeloid cells into the lungs of hßcTg mice. The therapeutic application of CSL311 potently decreased accumulation of monocytes/macrophages, neutrophils, and eosinophils without altering lung viral loads. Furthermore, CSL311 treatment did not limit the viral-induced expansion of NK and NKT cells, or the tissue expression of type I/II/III interferons needed for efficient viral clearance. Simultaneously blocking GM-CSF, IL-5 and IL-3 signalling with CSL311 may represent an improved and clinically applicable strategy to reducing hyperinflammation in the ARDS setting.


Subject(s)
Cytokine Receptor Common beta Subunit/genetics , Cytokine Receptor Common beta Subunit/physiology , Respiratory Distress Syndrome/immunology , Animals , Antibodies, Monoclonal/immunology , Cytokine Receptor Common beta Subunit/immunology , Cytokines , Eosinophils/immunology , Female , Humans , Immunity/genetics , Immunity/physiology , Inflammation/immunology , Leukocytes/metabolism , Male , Mice , Mice, Transgenic , Neutrophils/metabolism , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor , Receptors, Interleukin-3 , Receptors, Interleukin-5 , Respiratory Distress Syndrome/physiopathology
7.
Adv Protein Chem Struct Biol ; 129: 163-188, 2022.
Article in English | MEDLINE | ID: covidwho-1653881

ABSTRACT

Selectin enzymes are glycoproteins and are an important adhesion molecule in the mammalian immune system, especially in the inflammatory response and the healing process of tissues. Selectins play an important role in a variety of biological processes, including the rolling of leukocytes in endothelial cells, a process known as the adhesion cascade. It has recently been discovered and reported that the selectin mechanism plays a role in cancer and thrombosis disease. This process begins with non-covalent interactions-based selectin-ligand binding and the glycans play a role as a connector between cancer cells and the endothelium in this process. The selectin mechanism is critical for the immune system, but it is also involved in disease mechanisms, earning the selectins the nickname "Selectins-The Two Dr. Jekyll and Mr. Hyde Faces". As a result, the drug for selectins should have a multifaceted role and be a dynamic molecule that targets the disease mechanism specifically. This chapter explores the role of selectins in the disease mechanism at the mechanism level that provides the impact for identifying the selectin inhibitors. Overall, this chapter provides the molecular level insights on selectins, their ligands, involvement in normal and disease mechanisms.


Subject(s)
Endothelial Cells , Selectins , Animals , Endothelial Cells/metabolism , Humans , Leukocytes/metabolism , Ligands , Mammals/metabolism , Selectins/metabolism
8.
J Mol Med (Berl) ; 100(4): 569-584, 2022 04.
Article in English | MEDLINE | ID: covidwho-1653410

ABSTRACT

For over a year, the coronavirus disease 2019 has been affecting the world population by causing severe tissue injuries and death in infected people. Adenosine triphosphate (ATP) and the nicotinamide adenine dinucleotide (NAD +) are two molecules that are released into the extracellular microenvironment after direct virus infection or cell death caused by hyper inflammation and coagulopathy. Also, these molecules are well known to participate in multiple pathways and have a pivotal role in the purinergic signaling pathway. Thus, using public datasets available on the Gene Expression Omnibus (GEO), we analyzed raw proteomics data acquired using mass spectrometry (the gold standard method) and raw genomics data from COVID-19 patient samples obtained by microarray. The data was analyzed using bioinformatics and statistical methods according to our objectives. Here, we compared the purinergic profile of the total leukocyte population and evaluated the levels of these soluble biomolecules in the blood, and their correlation with coagulation components in COVID-19 patients, in comparison to healthy people or non-COVID-19 patients. The blood metabolite analysis showed a stage-dependent inosine increase in COVID-19 patients, while the nucleotides ATP and ADP had positive correlations with fibrinogen and other coagulation proteins. Also, ATP, ADP, inosine, and hypoxanthine had positive and negative correlations with clinical features. Regarding leukocyte gene expression, COVID-19 patients showed an upregulation of the P2RX1, P2RX4, P2RX5, P2RX7, P2RY1, P2RY12, PANX1, ADORA2B, NLPR3, and F3 genes. Yet, the ectoenzymes of the canonical and non-canonical adenosinergic pathway (ENTPD1 and CD38) are upregulated, suggesting that adenosine is produced by both active adenosinergic pathways. Hence, approaches targeting these biomolecules or their specific purinoreceptors and ectoenzymes may attenuate the high inflammatory state and the coagulopathy seen in COVID-19 patients. KEY MESSAGES : Adenosinergic pathways are modulated on leukocytes from COVID-19 patients. Plasmatic inosine levels are increased in COVID-19 patients. ATP, ADP, AMP, hypoxanthine, and inosine are correlated with coagulation players. The nucleotides and nucleosides are correlated with patients' clinical features. The P2 receptors and ectoenzymes are correlated with Tissue factor in COVID-19.


Subject(s)
COVID-19 , Adenosine/metabolism , Adenosine Triphosphate/metabolism , Connexins , Humans , Leukocytes/metabolism , Nerve Tissue Proteins , Signal Transduction
9.
JAMA Intern Med ; 182(3): 291-300, 2022 03 01.
Article in English | MEDLINE | ID: covidwho-1637435

ABSTRACT

Importance: Telomeres protect DNA from damage. Because they shorten with each mitotic cycle, leukocyte telomere length (LTL) serves as a mitotic clock. Reduced LTL has been associated with multiple human disorders. Objective: To determine the association between LTL and overall as well as disease-specific mortality and morbidity. Design, Setting, and Participants: This multicenter, community-based cohort study conducted from March 2006 to December 2010 included longitudinal follow-up (mean [SD], 12 [2] years) for 472 432 English participants from the United Kingdom Biobank (UK Biobank) and analyzed morbidity and mortality. The data were analyzed in 2021. Main Outcomes and Measures: Hazard ratios (HRs) and odds ratios for mortality and morbidity associated with a standard deviation change in LTL, adjusted for age, sex, body mass index (calculated as weight in kilograms divided by height in meters squared), and ethnicity. Results: This study included a total of 472 432 English participants, of whom 54% were women (mean age, 57 years). Reduced LTL was associated with increased overall (HR, 1.08; 95% CI, 1.07-1.09), cardiovascular (HR, 1.09; 95% CI, 1.06-1.12), respiratory (HR, 1.40; 95% CI, 1.34-1.45), digestive (HR, 1.26; 95% CI, 1.19-1.33), musculoskeletal (HR, 1.51; 95% CI, 1.35-1.92), and COVID-19 (HR, 1.15; 95% CI, 1.07-1.23) mortality, but not cancer-related mortality. A total of 214 disorders were significantly overrepresented and 37 underrepresented in participants with shorter LTL. Respiratory (11%), digestive/liver-related (14%), circulatory (18%), and musculoskeletal conditions (6%), together with infections (5%), accounted for most positive associations, whereas (benign) neoplasms and endocrinologic/metabolic disorders were the most underrepresented entities. Malignant tumors, esophageal cancer, and lymphoid and myeloid leukemia were significantly more common in participants with shorter LTL, whereas brain cancer and melanoma were less prevalent. While smoking and alcohol consumption were associated with shorter LTL, additional adjustment for both factors, as well as cognitive function/major comorbid conditions, did not significantly alter the results. Conclusions and Relevance: This cohort study found that shorter LTL was associated with a small risk increase of overall mortality, but a higher risk of mortality was associated with specific organs and diseases.


Subject(s)
Leukocytes/physiology , Mortality/trends , Telomere/physiology , Adult , Aged , Female , Follow-Up Studies , Humans , Longitudinal Studies , Male , Middle Aged , Risk , United Kingdom
10.
Front Immunol ; 12: 774776, 2021.
Article in English | MEDLINE | ID: covidwho-1581334

ABSTRACT

Both RNA N6-methyladenosine (m6A) modification of SARS-CoV-2 and immune characteristics of the human body have been reported to play an important role in COVID-19, but how the m6A methylation modification of leukocytes responds to the virus infection remains unknown. Based on the RNA-seq of 126 samples from the GEO database, we disclosed that there is a remarkably higher m6A modification level of blood leukocytes in patients with COVID-19 compared to patients without COVID-19, and this difference was related to CD4+ T cells. Two clusters were identified by unsupervised clustering, m6A cluster A characterized by T cell activation had a higher prognosis than m6A cluster B. Elevated metabolism level, blockage of the immune checkpoint, and lower level of m6A score were observed in m6A cluster B. A protective model was constructed based on nine selected genes and it exhibited an excellent predictive value in COVID-19. Further analysis revealed that the protective score was positively correlated to HFD45 and ventilator-free days, while negatively correlated to SOFA score, APACHE-II score, and crp. Our works systematically depicted a complicated correlation between m6A methylation modification and host lymphocytes in patients infected with SARS-CoV-2 and provided a well-performing model to predict the patients' outcomes.


Subject(s)
Adenosine/analogs & derivatives , COVID-19/immunology , COVID-19/virology , Host-Pathogen Interactions/immunology , Leukocytes/immunology , RNA, Viral/genetics , SARS-CoV-2/physiology , Adenosine/metabolism , Cluster Analysis , Computational Biology/methods , Disease Susceptibility/immunology , Gene Expression Profiling , Humans , Leukocytes/metabolism , RNA, Viral/metabolism , ROC Curve
11.
Viruses ; 13(12)2021 12 15.
Article in English | MEDLINE | ID: covidwho-1572672

ABSTRACT

Uncontrolled inflammatory responses play a critical role in coronavirus disease (COVID-19). In this context, because the triggering-receptor expressed on myeloid cells-1 (TREM-1) is considered an intrinsic amplifier of inflammatory signals, this study investigated the role of soluble TREM-1 (sTREM-1) as a biomarker of the severity and mortality of COVID-19. Based on their clinical scores, we enrolled COVID-19 positive patients (n = 237) classified into mild, moderate, severe, and critical groups. Clinical data and patient characteristics were obtained from medical records, and their plasma inflammatory mediator profiles were evaluated with immunoassays. Plasma levels of sTREM-1 were significantly higher among patients with severe disease compared to all other groups. Additionally, levels of sTREM-1 showed a significant positive correlation with other inflammatory parameters, such as IL-6, IL-10, IL-8, and neutrophil counts, and a significant negative correlation was observed with lymphocyte counts. Most interestingly, sTREM-1 was found to be a strong predictive biomarker of the severity of COVID-19 and was related to the worst outcome and death. Systemic levels of sTREM-1 were significantly correlated with the expression of matrix metalloproteinases (MMP)-8, which can release TREM-1 from the surface of peripheral blood cells. Our findings indicated that quantification of sTREM-1 could be used as a predictive tool for disease outcome, thus improving the timing of clinical and pharmacological interventions in patients with COVID-19.


Subject(s)
Biomarkers/blood , COVID-19/diagnosis , COVID-19/mortality , Leukocytes/metabolism , Matrix Metalloproteinase 8/metabolism , Severity of Illness Index , Triggering Receptor Expressed on Myeloid Cells-1/blood , Adolescent , Adult , Aged , Aged, 80 and over , Brazil , Female , Humans , Inflammation , Interleukin-10/blood , Interleukin-6/blood , Interleukin-8/blood , Leukocyte Count , Male , Middle Aged , Neutrophils/metabolism , Prospective Studies , SARS-CoV-2 , Triggering Receptor Expressed on Myeloid Cells-1/metabolism , Young Adult
12.
Viruses ; 13(12)2021 12 11.
Article in English | MEDLINE | ID: covidwho-1572660

ABSTRACT

Patients with COVID-19 generally raise antibodies against SARS-CoV-2 following infection, and the antibody level is positively correlated to the severity of disease. Whether the viral antibodies exacerbate COVID-19 through antibody-dependent enhancement (ADE) is still not fully understood. Here, we conducted in vitro assessment of whether convalescent serum enhanced SARS-CoV-2 infection or induced excessive immune responses in immune cells. Our data revealed that SARS-CoV-2 infection of primary B cells, macrophages and monocytes, which express variable levels of FcγR, could be enhanced by convalescent serum from COVID-19 patients. We also determined the factors associated with ADE, and found which showed a time-dependent but not viral-dose dependent manner. Furthermore, the ADE effect is not associated with the neutralizing titer or RBD antibody level when testing serum samples collected from different patients. However, it is higher in a medium level than low or high dilutions in a given sample that showed ADE effect, which is similar to dengue. Finally, we demonstrated more viral genes or dysregulated host immune gene expression under ADE conditions compared to the no-serum infection group. Collectively, our study provides insight into the understanding of an association of high viral antibody titer and severe lung pathology in severe patients with COVID-19.


Subject(s)
Antibody-Dependent Enhancement/immunology , Leukocytes/virology , SARS-CoV-2/pathogenicity , COVID-19/immunology , Cells, Cultured , Gene Expression Profiling , Humans , Immune Sera/immunology , Leukocytes/metabolism , Receptors, IgG/metabolism , Virus Replication/immunology
13.
BMC Infect Dis ; 21(1): 1236, 2021 Dec 09.
Article in English | MEDLINE | ID: covidwho-1566509

ABSTRACT

BACKGROUND: Peripheral hematological changes in severe COVID-19 patients may reflect the immune response during SARS-CoV-2 infection. Characteristics of peripheral white blood cells as early signals were needed to be investigated for clarifying its associations with the fatal outcomes in COVID-19 patients. METHODS: A retrospective cohort study was performed and the hospitalized COVID-19 patients were recruited in wards of Sino-French New City Branch of Tongji Hospital in Wuhan, Hubei province, China. Characteristics of peripheral white blood cells in survivors and non-survivors were analyzed. Comparison among patients with different level of eosinophils was performed. RESULTS: Of 198 patients included in this study, 185 were discharged and 13 died. Levels of eosinophils, lymphocytes and basophils in non-survivors were significantly lower than those in survivors. Death rate in low eosinophils group was higher and no patient died in normal eosinophils group (16.7% vs 0, P < 0.001). The proportion of patients in low eosinophils group who used glucocorticoids was higher than in normal eosinophils group, but glucocorticoids usage was not an indicator for death in subgroup analysis in low eosinophils patients. Moreover, positive correlation was found between the counts of lymphocytes and eosinophils in patients with glucocorticoids use but not in patients without the treatment. CONCLUSIONS: Hematological changes differed between survivors and non-survivors with COVID-19. Lymphopenia and eosinopenia could be predictors for poor prognosis of COVID-19 patients. Initial counts of eosinophils may guide us in usage of glucocorticoids for COVID-19 treatment.


Subject(s)
COVID-19 , COVID-19/drug therapy , China , Humans , Leukocytes , Retrospective Studies , SARS-CoV-2
14.
Free Radic Res ; 55(9-10): 982-995, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1555313

ABSTRACT

The inflammation and activation of the immune system induced by SARS-CoV-2 are mediated by a pro-oxidant microenvironment that can induce cytotoxic effects that enhance tissue damage, favoring organic deterioration. We investigated whether the induction of oxidative stress and inflammation by COVID-19 infection could inhibit mitochondrial function and cause cellular damage in leukocytes. We evaluated levels of oxidative/inflammation markers and their correlation with mitochondrial function and leukocyte cell death in COVID-19 patients at two moments: viremia and severe sepsis with multi-organ failure. COVID-19 induces increased oxidative stress and inflammation markers that activate cellular damage processes. In the viremia stage, an increase in peroxide, nitric oxide, carbonylated proteins, and IL-6 was observed, which was correlated with a marked inhibition of mitochondrial function, decreased cell viability, early apoptosis, necrosis, and leukocytes-reactivity. The severe sepsis stage with multi-organ failure also showed a further increase in levels of peroxide, carbonylated proteins, and IL-6, with a slight decrease in nitric oxide. This oxidative process and inflammation were correlated with less inhibition of mitochondrial function, decreased cell viability and an increase in late apoptosis, and morphology changes evidencing damage in the leukocytes. SARS-CoV-2 induced damage promotes levels of oxidative stress and inflammation markers and mitochondrial dysfunction that potentiate morphological changes and cell death in leukocytes. These processes explain the rapid changes in the immune system, and that present an initial over-activation and early massive death due to SARS-CoV-2 infection, promoting endothelial-alveolar damage that would cause multi-organ failure, sustained by oxidative stress and inflammation.


Subject(s)
COVID-19 , Cell Death , Humans , Inflammation , Leukocytes , Mitochondria , Oxidative Stress , SARS-CoV-2
15.
Int J Mol Sci ; 22(22)2021 Nov 16.
Article in English | MEDLINE | ID: covidwho-1534087

ABSTRACT

Five novel analogs of 6-(ethyl)(4-isobutoxy-3-isopropylphenyl)amino)nicotinic acid-or NEt-4IB-in addition to seven novel analogs of 4-[1-(3,5,5,8,8-pentamethyl-5,6,7,8-tetrahydro-2-naphthyl)ethynyl]benzoic acid (bexarotene) were prepared and evaluated for selective retinoid-X-receptor (RXR) agonism alongside bexarotene (1), a FDA-approved drug for cutaneous T-cell lymphoma (CTCL). Bexarotene treatment elicits side-effects by provoking or disrupting other RXR-dependent pathways. Analogs were assessed by the modeling of binding to RXR and then evaluated in a human cell-based RXR-RXR mammalian-2-hybrid (M2H) system as well as a RXRE-controlled transcriptional system. The analogs were also tested in KMT2A-MLLT3 leukemia cells and the EC50 and IC50 values were determined for these compounds. Moreover, the analogs were assessed for activation of LXR in an LXRE system as drivers of ApoE expression and subsequent use as potential therapeutics in neurodegenerative disorders, and the results revealed that these compounds exerted a range of differential LXR-RXR activation and selectivity. Furthermore, several of the novel analogs in this study exhibited reduced RARE cross-signaling, implying RXR selectivity. These results demonstrate that modification of partial agonists such as NEt-4IB and potent rexinoids such as bexarotene can lead to compounds with improved RXR selectivity, decreased cross-signaling of other RXR-dependent nuclear receptors, increased LXRE-heterodimer selectivity, and enhanced anti-proliferative potential in leukemia cell lines compared to therapeutics such as 1.


Subject(s)
Antineoplastic Agents/pharmacology , Apolipoproteins E/genetics , Bexarotene/pharmacology , Leukocytes/drug effects , Nicotinic Acids/pharmacology , Retinoid X Receptor alpha/agonists , Animals , Antineoplastic Agents/chemical synthesis , Apolipoproteins E/metabolism , Bexarotene/analogs & derivatives , Bexarotene/chemical synthesis , Cell Line, Tumor , Dose-Response Relationship, Drug , Gene Expression , Humans , Leukocytes/metabolism , Leukocytes/pathology , Nicotinic Acids/chemical synthesis , Retinoid X Receptor alpha/genetics , Retinoid X Receptor alpha/metabolism , Structure-Activity Relationship
16.
Viruses ; 13(11)2021 11 08.
Article in English | MEDLINE | ID: covidwho-1512696

ABSTRACT

Survivors of severe SARS-CoV-2 infections frequently suffer from a range of post-infection sequelae. Whether survivors of mild or asymptomatic infections can expect any long-term health consequences is not yet known. Herein we investigated lasting changes to soluble inflammatory factors and cellular immune phenotype and function in individuals who had recovered from mild SARS-CoV-2 infections (n = 22), compared to those that had recovered from other mild respiratory infections (n = 11). Individuals who had experienced mild SARS-CoV-2 infections had elevated levels of C-reactive protein 1-3 months after symptom onset, and changes in phenotype and function of circulating T-cells that were not apparent in individuals 6-9 months post-symptom onset. Markers of monocyte activation, and expression of adherence and chemokine receptors indicative of altered migratory capacity, were also higher at 1-3 months post-infection in individuals who had mild SARS-CoV-2, but these were no longer elevated by 6-9 months post-infection. Perhaps most surprisingly, significantly more T-cells could be activated by polyclonal stimulation in individuals who had recently experienced a mild SARS-CoV-2, infection compared to individuals with other recent respiratory infections. These data are indicative of prolonged immune activation and systemic inflammation that persists for at least three months after mild or asymptomatic SARS-CoV-2 infections.


Subject(s)
Asymptomatic Infections , COVID-19/immunology , Cytokines/metabolism , Leukocytes/immunology , Leukocytes/metabolism , Respiratory Tract Infections/immunology , SARS-CoV-2/immunology , Adult , Aged , Antibodies, Viral , Biomarkers , C-Reactive Protein/immunology , C-Reactive Protein/metabolism , COVID-19/virology , Cytokines/immunology , Female , Humans , Immunophenotyping/methods , Inflammation/metabolism , Inflammation/virology , Lymphocyte Activation , Male , Middle Aged , Respiratory Tract Infections/virology , Spike Glycoprotein, Coronavirus/immunology , Survivors , T-Lymphocytes/immunology , T-Lymphocytes/metabolism
17.
Int Immunopharmacol ; 101(Pt A): 108292, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1487772

ABSTRACT

Leukopenia is a common manifestation of many diseases, including global outbreak SAS-CoV-2 infection. Granulocyte-macrophage colony-stimulating factor (GM -CSF) has been proved to be effective in promoting lymphocyte regeneration, but adverse immunological effects have also emerged. This study aim to investigate the effect of GM -CSF on BCR heavy chain CDR3 repertoire while promoting lymphocyte regeneration. Cyclophosphamide (CTX) and GM -CSF were used to inhibit and stimulate bone marrow hematopoiesis, respectively. High throughput sequencing was applied to detect the characteristics of BCR CDR3 repertoire in controls, CTX group and GM -CSF group. The white blood cells (WBCs) were quickly reduced (P < 0.05) with lymphocytes decreasing causing by CTX, and the WBCs and lymphocytes returned to the level of controls after GM -CSF treatment. The diversity of BCR heavy chain CDR3 repertoire was also significantly decreased in CTX group. Although there is still a big gap from the controls, the diversity was picked up after GM -CSF treatment. The expression of IGHD01-01, IGHD02-14 and IGHJ04-01 with high-frequency usage regularly and significantly changed in three groups, and many genes with low-frequency usage lost in CTX group and did not reappear in GM -CSF group. Moreover, two shared sequences and accounted for the highest proportion in GM -CSF group have been detected in animal model of chronic lymphocytic leukemia. These results revealed that GM -CSF can partially restore changes in the BCR heavy chain CDR3 repertoire while promoting lymphocyte regeneration, but it may also lead to rearrangement, proliferation and activation of abnormal B cells, which can provide a basis for further study on the adverse immunological effects and mechanism of GM -CSF treatment.


Subject(s)
Cyclophosphamide/adverse effects , Granulocyte-Macrophage Colony-Stimulating Factor/immunology , Leukopenia/immunology , Lymphocytes/drug effects , Lymphocytes/immunology , Receptors, Antigen, B-Cell/drug effects , Receptors, Antigen, B-Cell/metabolism , Animals , Complementarity Determining Regions/drug effects , Complementarity Determining Regions/genetics , Complementarity Determining Regions/metabolism , Cyclophosphamide/therapeutic use , Female , Granulocyte-Macrophage Colony-Stimulating Factor/therapeutic use , Immunoglobulin Heavy Chains/drug effects , Immunoglobulin Heavy Chains/genetics , Immunoglobulin Heavy Chains/metabolism , Immunoglobulin Joining Region/drug effects , Immunoglobulin Joining Region/metabolism , Immunoglobulin Variable Region/drug effects , Immunoglobulin Variable Region/metabolism , Leukocytes/drug effects , Leukopenia/chemically induced , Leukopenia/drug therapy , Lymphocytes/metabolism , Mice, Inbred BALB C , Receptors, Antigen, B-Cell/immunology
18.
Physiol Rep ; 9(20): e15075, 2021 10.
Article in English | MEDLINE | ID: covidwho-1485552

ABSTRACT

Exercise has substantial health benefits, but the effects of exercise on immune status and susceptibility to respiratory infections are less clear. Furthermore, there is limited research examining the effects of prolonged exercise on local respiratory immunity and antiviral activity. To assess the upper respiratory tract in response to exercise, we collected nasal lavage fluid (NALF) from human subjects (1) at rest, (2) after 45 min of moderate-intensity exercise, and (3) after 180 min of moderate-intensity exercise. To assess immune responses of the lower respiratory tract, we utilized a murine model to examine the effect of exercise duration on bronchoalveolar lavage (BAL) fluid immune cell content and lung gene expression. NALF cell counts did not change after 45 min of exercise, whereas 180 min significantly increased total cells and leukocytes in NALF. Importantly, fold change in NALF leukocytes correlated with the post-exercise fatigue rating in the 180-min exercise condition. The acellular portion of NALF contained strong antiviral activity against Influenza A in both resting and exercise paradigms. In mice undergoing moderate-intensity exercise, BAL total cells and neutrophils decreased in response to 45 or 90 min of exercise. In lung lobes, increased expression of heat shock proteins suggested that cellular stress occurred in response to exercise. However, a broad upregulation of inflammatory genes was not observed, even at 180 min of exercise. This work demonstrates that exercise duration differentially alters the cellularity of respiratory tract fluids, antiviral activity, and gene expression. These changes in local mucosal immunity may influence resistance to respiratory viruses, including influenza or possibly other pathogens in which nasal mucosa plays a protective role, such as rhinovirus or SARS-CoV-2.


Subject(s)
Exercise/physiology , Influenza A virus/immunology , Leukocytes/immunology , Lung/immunology , Nasal Lavage Fluid/immunology , Neutrophils/immunology , Adolescent , Adult , Animals , Bronchoalveolar Lavage Fluid/cytology , Bronchoalveolar Lavage Fluid/immunology , Female , Gene Expression , Humans , Leukocytes/metabolism , Lung/cytology , Lung/metabolism , Male , Mice , Mice, Inbred BALB C , Nasal Lavage/methods , Nasal Lavage Fluid/cytology , Nasal Mucosa/cytology , Nasal Mucosa/immunology , Nasal Mucosa/metabolism , Neutrophils/metabolism , Time Factors , Young Adult
19.
Front Endocrinol (Lausanne) ; 12: 727419, 2021.
Article in English | MEDLINE | ID: covidwho-1444039

ABSTRACT

Background: Blood parameters, such as neutrophil-to-lymphocyte ratio, have been identified as reliable inflammatory markers with diagnostic and predictive value for the coronavirus disease 2019 (COVID-19). However, novel hematological parameters derived from high-density lipoprotein-cholesterol (HDL-C) have rarely been studied as indicators for the risk of poor outcomes in patients with severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) infection. Here, we aimed to assess the prognostic value of these novel biomarkers in COVID-19 patients and the diabetes subgroup. Methods: We conducted a multicenter retrospective cohort study involving all hospitalized patients with COVID-19 from January to March 2020 in five hospitals in Wuhan, China. Demographics, clinical and laboratory findings, and outcomes were recorded. Neutrophil to HDL-C ratio (NHR), monocyte to HDL-C ratio (MHR), lymphocyte to HDL-C ratio (LHR), and platelet to HDL-C ratio (PHR) were investigated and compared in both the overall population and the subgroup with diabetes. The associations between blood parameters at admission with primary composite end-point events (including mechanical ventilation, admission to the intensive care unit, or death) were analyzed using Cox proportional hazards regression models. Receiver operating characteristic curves were used to compare the utility of different blood parameters. Results: Of 440 patients with COVID-19, 67 (15.2%) were critically ill. On admission, HDL-C concentration was decreased while NHR was high in patients with critical compared with non-critical COVID-19, and were independently associated with poor outcome as continuous variables in the overall population (HR: 0.213, 95% CI 0.090-0.507; HR: 1.066, 95% CI 1.030-1.103, respectively) after adjusting for confounding factors. Additionally, when HDL-C and NHR were examined as categorical variables, the HRs and 95% CIs for tertile 3 vs. tertile 1 were 0.280 (0.128-0.612) and 4.458 (1.817-10.938), respectively. Similar results were observed in the diabetes subgroup. ROC curves showed that the NHR had good performance in predicting worse outcomes. The cutoff point of the NHR was 5.50. However, the data in our present study could not confirm the possible predictive effect of LHR, MHR, and PHR on COVID-19 severity. Conclusion: Lower HDL-C concentrations and higher NHR at admission were observed in patients with critical COVID-19 than in those with noncritical COVID-19, and were significantly associated with a poor prognosis in COVID-19 patients as well as in the diabetes subgroup.


Subject(s)
COVID-19/blood , Cholesterol, HDL/blood , Diabetes Mellitus/blood , Aged , Biomarkers/blood , COVID-19/diagnosis , COVID-19/mortality , China , Diabetes Mellitus/diagnosis , Diabetes Mellitus/mortality , Female , Humans , Kaplan-Meier Estimate , Leukocytes/cytology , Male , Middle Aged , Prognosis , ROC Curve , Retrospective Studies , Severity of Illness Index
20.
J Leukoc Biol ; 110(6): 1253-1268, 2021 12.
Article in English | MEDLINE | ID: covidwho-1437055

ABSTRACT

Systemic infections, especially in patients with chronic diseases, may result in sepsis: an explosive, uncoordinated immune response that can lead to multisystem organ failure with a high mortality rate. Patients with similar clinical phenotypes or sepsis biomarker expression upon diagnosis may have different outcomes, suggesting that the dynamics of sepsis is critical in disease progression. A within-subject study of patients with Gram-negative bacterial sepsis with surviving and fatal outcomes was designed and single-cell transcriptomic analyses of peripheral blood mononuclear cells (PBMC) collected during the critical period between sepsis diagnosis and 6 h were performed. The single-cell observations in the study are consistent with trends from public datasets but also identify dynamic effects in individual cell subsets that change within hours. It is shown that platelet and erythroid precursor responses are drivers of fatal sepsis, with transcriptional signatures that are shared with severe COVID-19 disease. It is also shown that hypoxic stress is a driving factor in immune and metabolic dysfunction of monocytes and erythroid precursors. Last, the data support CD52 as a prognostic biomarker and therapeutic target for sepsis as its expression dynamically increases in lymphocytes and correlates with improved sepsis outcomes. In conclusion, this study describes the first single-cell study that analyzed short-term temporal changes in the immune cell populations and their characteristics in surviving or fatal sepsis. Tracking temporal expression changes in specific cell types could lead to more accurate predictions of sepsis outcomes and identify molecular biomarkers and pathways that could be therapeutically controlled to improve the sepsis trajectory toward better outcomes.


Subject(s)
COVID-19/immunology , Gram-Negative Bacterial Infections/immunology , Leukocytes , Sepsis/immunology , Transcriptome/immunology , Adult , Aged , Aged, 80 and over , Female , Humans , Inflammation/immunology , Male , Middle Aged , Retrospective Studies , SARS-CoV-2 , Single-Cell Analysis
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