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1.
iScience ; 24(12): 103426, 2021 Dec 17.
Article in English | MEDLINE | ID: covidwho-1509907

ABSTRACT

Glycosylation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike glycoprotein mediates viral entry and immune escape. While glycan site is determined by viral genetic code, glycosylation is completely dependent on host cell post-translational modification. Here, by producing SARS-CoV-2 virions from various host cell lines, viruses of different origins with diverse spike protein glycan patterns were revealed. Binding affinities to C-type lectin receptors (CLRs) DC&L-SIGN differed in the different glycan pattern virions. Although none of the CLRs supported viral productive infection, viral trans&cis-infection mediated by the CLRs were substantially changed among the different virions. Specifically, trans&cis-infection of virions with a high-mannose structure (Man5GlcNAc2) at the N1098 glycan site of the spike postfusion trimer were markedly enhanced. Considering L-SIGN co-expression with ACE2 on respiratory tract cells, our work underlines viral epigenetic glycosylation in authentic viral infection and highlights the attachment co-receptor role of DC&L-SIGN in SARS-CoV-2 infection and prevention.

4.
Mol Ther Methods Clin Dev ; 23: 108-118, 2021 Dec 10.
Article in English | MEDLINE | ID: covidwho-1379195

ABSTRACT

Because of the relatively limited understanding of coronavirus disease 2019 (COVID-19) pathogenesis, immunological analysis for vaccine development is needed. Mice and macaques were immunized with an inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine prepared by two inactivators. Various immunological indexes were tested, and viral challenges were performed on day 7 or 150 after booster immunization in monkeys. This inactivated SARS-CoV-2 vaccine was produced by sequential inactivation with formaldehyde followed by propiolactone. The various antibody responses and specific T cell responses to different viral antigens elicited in immunized animals were maintained for longer than 150 days. This comprehensive immune response could effectively protect vaccinated macaques by inhibiting viral replication in macaques and substantially alleviating immunopathological damage, and no clinical manifestation of immunopathogenicity was observed in immunized individuals during viral challenge. This candidate inactivated vaccine was identified as being effective against SARS-CoV-2 challenge in rhesus macaques.

5.
Front Med (Lausanne) ; 8: 708140, 2021.
Article in English | MEDLINE | ID: covidwho-1372657

ABSTRACT

Naive CD4+ T cells can differentiate into different cell subsets after receiving antigen stimulation, which secrete corresponding characteristic cytokines and thereby exert biological effects in various diseases. Th22 cells, a novel subset of CD4+ T cells, are different from Th1, Th2, Th17, and Treg cell subsets, which have been discovered in recent years. They can express CCR4, CCR6, and CCR10 molecules and secrete IL-22, IL-13, and TNF-α. They are not able to secrete IL-17, IL-4, and interferon-γ (IFN-γ). IL-22 is considered as a major effector molecule of Th22 cells whose functions and mechanisms of regulating cell differentiation have been constantly improved. In this review, we provide an overview of the origin, differentiation of Th22 cells. Moreover, we also describe the interrelationships between Th22 cells and Th17, Th1, and Th2 cells. Additionally, the role of Th22 cells were discussed in human diseases with virus infection, which will provide novel insight for the prevention and treatment of viral infection in human.

6.
Journal of Physics: Conference Series ; 1978(1), 2021.
Article in English | ProQuest Central | ID: covidwho-1327334

ABSTRACT

The COVID-19 epidemic has had a major impact on people’s lives around the world, and many countries and regions have adopted voluntary nucleic acid testing with mandatory isolation for confirmed household to control COVID-19. Based on the method of branching process, this paper analyzes the influence of related factors on the control effect of voluntary nucleic acid testing with mandatory isolation for confirmed household by establishing a specific household model. Through numerical simulation and comparative analysis, we found that increasing the proportion of voluntary nucleic acid testing and shortening the start time of voluntary testing could enhance the epidemic control effect of this measure. At the same time, the proportion of the symptomatic will also have an impact on the effectiveness of the measure.

7.
Bioconjug Chem ; 32(5): 1034-1046, 2021 05 19.
Article in English | MEDLINE | ID: covidwho-1217668

ABSTRACT

SARS-CoV-2 caused the COVID-19 pandemic that lasted for more than a year. Globally, there is an urgent need to use safe and effective vaccines for immunization to achieve comprehensive protection against SARS-CoV-2 infection. Focusing on developing a rapid vaccine platform with significant immunogenicity as well as broad and high protection efficiency, we designed a SARS-CoV-2 spike protein receptor-binding domain (RBD) displayed on self-assembled ferritin nanoparticles. In a 293i cells eukaryotic expression system, this candidate vaccine was prepared and purified. After rhesus monkeys are immunized with 20 µg of RBD-ferritin nanoparticles three times, the vaccine can elicit specific humoral immunity and T cell immune response, and the neutralizing antibodies can cross-neutralize four SARS-CoV-2 strains from different sources. In the challenge protection test, after nasal infection with 2 × 105 CCID50 SARS-CoV-2 virus, compared with unimmunized control animals, virus replication in the vaccine-immunized rhesus monkeys was significantly inhibited, and respiratory pathology observations also showed only slight pathological damage. These analyses will benefit the immunization program of the RBD-ferritin nanoparticle vaccine in the clinical trial design and the platform construction to present a specific antigen domain in the self-assembling nanoparticle in a short time to harvest stable, safe, and effective vaccine candidates for new SARS-CoV-2 isolates.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/prevention & control , Nanoparticles/chemistry , Spike Glycoprotein, Coronavirus/metabolism , T-Lymphocytes/immunology , Animals , Antibodies, Neutralizing/immunology , Binding Sites , CD8-Positive T-Lymphocytes/immunology , COVID-19/immunology , Ferritins/chemistry , Ferritins/metabolism , Immunity, Humoral , Macaca mulatta , Male , Nanoparticles/metabolism , SARS-CoV-2/isolation & purification , SARS-CoV-2/physiology , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , T-Lymphocytes/metabolism , Ultracentrifugation
8.
Cell Rep Med ; 2(4): 100242, 2021 Apr 20.
Article in English | MEDLINE | ID: covidwho-1155661

ABSTRACT

Severe SARS-CoV-2 infection often leads to the development of acute respiratory distress syndrome (ARDS), with profound pulmonary patho-histological changes post-mortem. It is not clear whether ARDS from SARS-CoV-2 is similar to that observed in influenza H1N1, another common viral cause of lung injury. Here, we analyze specific ARDS regions of interest utilizing a spatial transcriptomic platform on autopsy-derived lung tissue from patients with SARS-CoV-2 (n = 3), H1N1 (n = 3), and a dual infected individual (n = 1). Enhanced gene signatures in alveolar epithelium, vascular tissue, and lung macrophages identify not only increased regional coagulopathy but also increased extracellular remodeling, alternative macrophage activation, and squamous metaplasia of type II pneumocytes in SARS-CoV-2. Both the H1N1 and dual-infected transcriptome demonstrated an enhanced antiviral response compared to SARS-CoV-2. Our results uncover regional transcriptional changes related to tissue damage/remodeling, altered cellular phenotype, and vascular injury active in SARS-CoV-2 and present therapeutic targets for COVID-19-related ARDS.

9.
Front Pharmacol ; 11: 615972, 2020.
Article in English | MEDLINE | ID: covidwho-1004690

ABSTRACT

Background: Interleukin-6 (IL-6) is known to be detrimental in coronavirus disease 2019 (COVID-19) because of its involvement in driving cytokine storm. This systematic review and meta-analysis aimed to assess the safety and efficacy of anti-IL-6 signaling (anti-IL6/IL-6R/JAK) agents on COVID-19 based on the current evidence. Methods: Studies were identified through systematic searches of PubMed, EMBASE, ISI Web of Science, Cochrane library, ongoing clinical trial registries (clinicaltrials.gov), and preprint servers (medRxiv, ChinaXiv) on August 10, 2020, as well as eligibility checks according to predefined selection criteria. Statistical analysis was performed using Review Manager (version 5.3) and STATA 12.0. Results: Thirty-one studies were included in the pooled analysis of mortality, and 12 studies were identified for the analysis of risk of secondary infections. For mortality analysis, 5630 COVID-19 cases including 2,132 treated patients and 3,498 controls were analyzed. Anti-IL-6 signaling agents plus standard of care (SOC) significantly decreased the mortality rate compared to SOC alone (pooled OR = 0.61, 95% CI 0.45-0.84, p = 0.002). For the analysis of secondary infection risk, 1,624 patients with COVID-19 including 639 treated patients and 985 controls were included, showing that anti-IL-6 signaling agents did not increase the rate of secondary infections (pooled OR = 1.21, 95% CI 0.70-2.08, p = 0.50). By contrast, for patients with critical COVID-19 disease, anti-IL-6 signaling agents failed to reduce mortality compared to SOC alone (pooled OR = 0.75, 95% CI 0.42-1.33, p = 0.33), but they tended to increase the risk of secondary infections (pooled OR = 1.85, 95% CI 0.95-3.61, p = 0.07). A blockade of IL-6 signaling failed to reduce the mechanical ventilation rate, ICU admission rate, or elevate the clinical improvement rate. Conclusion: IL-6 signaling inhibitors reduced the mortality rate without increasing secondary infections in patients with COVID-19 based on current studies. For patients with critical disease, IL-6 signaling inhibitors did not exhibit any benefit.

10.
Zool Res ; 41(6): 621-631, 2020 11 18.
Article in English | MEDLINE | ID: covidwho-982982

ABSTRACT

Understanding the pathogenesis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and clarifying antiviral immunity in hosts are critical aspects for the development of vaccines and antivirals. Mice are frequently used to generate animal models of infectious diseases due to their convenience and ability to undergo genetic manipulation. However, normal adult mice are not susceptible to SARS-CoV-2. Here, we developed a viral receptor (human angiotensin-converting enzyme 2, hACE2) pulmonary transfection mouse model to establish SARS-CoV-2 infection rapidly in the mouse lung. Based on the model, the virus successfully infected the mouse lung 2 days after transfection. Viral RNA/protein, innate immune cell infiltration, inflammatory cytokine expression, and pathological changes in the infected lungs were observed after infection. Further studies indicated that neutrophils were the first and most abundant leukocytes to infiltrate the infected lungs after viral infection. In addition, using infected CXCL5-knockout mice, chemokine CXCL5 was responsible for neutrophil recruitment. CXCL5 knockout decreased lung inflammation without diminishing viral clearance, suggesting a potential target for controlling pneumonia.


Subject(s)
Betacoronavirus/immunology , Chemokine CXCL5/immunology , Coronavirus Infections/immunology , Immunity, Innate/immunology , Neutrophils/immunology , Peptidyl-Dipeptidase A/immunology , Pneumonia, Viral/immunology , Angiotensin-Converting Enzyme 2 , Animals , Betacoronavirus/genetics , Betacoronavirus/physiology , COVID-19 , Cell Line , Chemokine CXCL5/genetics , Chemokine CXCL5/metabolism , Coronavirus Infections/genetics , Coronavirus Infections/virology , Cytokines/immunology , Cytokines/metabolism , Disease Models, Animal , Humans , Male , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Neutrophils/metabolism , Neutrophils/virology , Pandemics , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Pneumonia, Viral/genetics , Pneumonia, Viral/virology , SARS-CoV-2
11.
PLoS Pathog ; 16(11): e1008949, 2020 11.
Article in English | MEDLINE | ID: covidwho-922716

ABSTRACT

The COVID-19 has emerged as an epidemic, causing severe pneumonia with a high infection rate globally. To better understand the pathogenesis caused by SARS-CoV-2, we developed a rhesus macaque model to mimic natural infection via the nasal route, resulting in the SARS-CoV-2 virus shedding in the nose and stool up to 27 days. Importantly, we observed the pathological progression of marked interstitial pneumonia in the infected animals on 5-7 dpi, with virus dissemination widely occurring in the lower respiratory tract and lymph nodes, and viral RNA was consistently detected from 5 to 21 dpi. During the infection period, the kinetics response of T cells was revealed to contribute to COVID-19 progression. Our findings implied that the antiviral response of T cells was suppressed after 3 days post infection, which might be related to increases in the Treg cell population in PBMCs. Moreover, two waves of the enhanced production of cytokines (TGF-α, IL-4, IL-6, GM-CSF, IL-10, IL-15, IL-1ß), chemokines (MCP-1/CCL2, IL-8/CXCL8, and MIP-1ß/CCL4) were detected in lung tissue. Our data collected from this model suggested that T cell response and cytokine/chemokine changes in lung should be considered as evaluation parameters for COVID-19 treatment and vaccine development, besides of observation of virus shedding and pathological analysis.


Subject(s)
Betacoronavirus/pathogenicity , Coronavirus Infections/pathology , Pneumonia, Viral/pathology , Animals , COVID-19 , Coronavirus Infections/drug therapy , Coronavirus Infections/virology , Cytokines/immunology , Disease Models, Animal , Lung/immunology , Lung/pathology , Macaca mulatta , Pandemics , Pneumonia, Viral/virology , SARS-CoV-2 , Viral Load/methods , Virulence , Virus Shedding
12.
J Med Virol ; 92(11): 2830-2838, 2020 11.
Article in English | MEDLINE | ID: covidwho-848038

ABSTRACT

Coronavirus disease 2019, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), leads to a series of clinical symptoms of respiratory and pulmonary inflammatory reactions via unknown pathologic mechanisms related to the viral infection process in tracheal or bronchial epithelial cells. Investigation of this viral infection in the human bronchial epithelial cell line (16HBE) suggests that SARS-CoV-2 can enter these cells through interaction between its membrane-localized S protein with the angiotensin-converting enzyme 2 molecule on the host cell membrane. Further observation indicates distinct viral replication with a dynamic and moderate increase, whereby viral replication does not lead to a specific cytopathic effect but maintains a continuous release of progeny virions from infected cells. Although messenger RNA expression of various innate immune signaling molecules is altered in the cells, transcription of interferons-α (IFN-α), IFN-ß, and IFN-γ is unchanged. Furthermore, expression of some interleukins (IL) related to inflammatory reactions, such as IL-6, IL-2, and IL-8, is maintained at low levels, whereas that of ILs involved in immune regulation is upregulated. Interestingly, IL-22, an IL that functions mainly in tissue repair, shows very high expression. Collectively, these data suggest a distinct infection process for this virus in respiratory epithelial cells, which may be linked to its clinicopathological mechanism.


Subject(s)
Bronchi/cytology , Epithelial Cells/virology , SARS-CoV-2/physiology , Virus Replication , Angiotensin-Converting Enzyme 2/metabolism , COVID-19/virology , Cell Line , Cytopathogenic Effect, Viral/immunology , Epithelial Cells/immunology , Humans , Immunity, Innate , Interleukins/immunology , Spike Glycoprotein, Coronavirus/metabolism
13.
Int J Gynaecol Obstet ; 151(3): 399-406, 2020 Dec.
Article in English | MEDLINE | ID: covidwho-743653

ABSTRACT

OBJECTIVE: To evaluate fertility intensions among couples in Shanghai under the novel coronavirus infection (COVID-19) pandemic against the backdrop of persistently low fertility. METHODS: A cross-sectional study was carried out using data from studies conducted before the COVID-19 pandemic. Data were collected regarding sociodemographic characteristics, history of reproduction and gynecology, fertility intention before and after the COVID-19 pandemic, female psychological state, and the impact of the COVID-19 pandemic on daily life. RESULTS: Under the influence of COVID-19, 296/447 (66.2%) participants did not change their original fertility intention to have children, while 151/447 (33.8%) of participants were affected by the outbreak. Participants who believed in government and hospital control policies were less likely to change their intention to become pregnant (P < 10-3 , P < 10-3 ). In contrast, concerns about the impact of COVID-19 on female and fetal health led participants to cancel their original pregnancy plans (P < 10-3 ). CONCLUSION: Three in ten couples of childbearing age, who originally expressed their intention of becoming pregnant, canceled their pregnancy plans after the COVID-19 outbreak. The COVID-19 outbreak has brought new challenges to people's physical and mental health. Effective policies and measures can help to improve people's fertility intentions with respect to having children.


Subject(s)
COVID-19/psychology , Family Planning Services , Fertility , Adult , China , Cross-Sectional Studies , Female , Humans , Intention , Male , Pandemics , SARS-CoV-2 , Sexual Partners/psychology , Young Adult
14.
Chinese Journal of Trauma ; (12): 117-123, 2020.
Article in Chinese | WPRIM (Western Pacific) | ID: covidwho-6326

ABSTRACT

Since December 2019, the corona virus disease 2019 (COVID-19) caused by the 2019 novel coronavirus (2019-nCoV) has been reported in Wuhan, Hubei Province. Almost 70% of patients susceptible to 2019-nCoV are over age of 50 years, with extremely large proportion of critical illness and death of the elderly patients. Meanwhile, the elderly patients are at high risk of osteoporotic fractures especially osteoporotic vertebral compression fractures (OVCF). During the prevention and control of COVID-19 epidemic, orthopedists are confronted with the following difficulties including how to screen and protect OVCF patients, how to accurately diagnose and assess the condition of OVCF patients with suspected or confirmed COVID-19, and how to develop reasonable treatment plans and comprehensive protective measures in emergency and outpatient clinics. In order to standardize the diagnosis and treatment of patients with OVCF diagnosed with COVID-19, the authors jointly develop this expert consensus. The consensus systematically recommends the standardized emergency and outpatient screening and confirmation procedures for OVCF patients with suspected or confirmed COVID-19 and protective measures for emergency and outpatient clinics. Moreover, the consensus describes the grading and classification of OVCF patients diagnosed with COVID-19 according to the severity of illness and recommends different treatment plans and corresponding protective measures based on the different types and epidemic prevention and control requirements.

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