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1.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-335525

ABSTRACT

Background: Currently, rapid and widespread testing is essential to promote early intervention and curb the ongoing COVID-19 pandemic. The reverse transcription-polymerase chain reaction (RT-PCR) for detecting novel coronavirus (SARS-CoV-2) is restricted to professional laboratories and well-trained personnel, thus, limiting its widespread use in in resource-limited conditions. Methods: To overcome these challenges, we developed a rapid and convenient assay using recombinase polymerase amplification (RPA) and clustered regularly interspaced short palindromic repeats (CRISPR) technology for the rapid detection SARS-CoV-2, which was named as Visual Detection of RPA-amplified Products (VDAP). The reaction conditions of the VDAP were optimized and selected using pure SARS-CoV-2 RNA standards and the sensitivity and specificity of the VDAP were further determined. Finally, the VDAP was verified on clinical specimens. Results: The VDAP was performed at 37 °C for 15 min, and the result was visible by the naked eye. The limits of detection (LODs) of the VDAP for the target ORF1ab and N genes are 70 and 500 copies, respectively. No cross-reactivity was observed with the RNA standard samples of four respiratory viruses or clinical samples of common respiratory viral infections. These results confirmed that the assay was highly specific. Thirty SARS-CoV-2 positive and 30 SARS-CoV-2 negative patient specimens were analyzed. We compared these results to RT-PCR, the overall sensitivity and specificity of the VDAP compared to RT-PCR for detection SARS-CoV-2 were 93.3% and 100.0%, respectively. Conclusions: The VDAP is a simple, highly specific, and convenient assay for the detection of SARS-CoV-2 in resource-limited conditions

2.
J Virol ; : e0003822, 2022 Apr 14.
Article in English | MEDLINE | ID: covidwho-1788914

ABSTRACT

Due to the limitation of human studies with respect to individual difference or the accessibility of fresh tissue samples, how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection results in pathological complications in lung, the main site of infection, is still incompletely understood. Therefore, physiologically relevant animal models under realistic SARS-CoV-2 infection conditions would be helpful to our understanding of dysregulated inflammation response in lung in the context of targeted therapeutics. Here, we characterized the single-cell landscape in lung and spleen upon SARS-CoV-2 infection in an acute severe disease mouse model that replicates human symptoms, including severe lung pathology and lymphopenia. We showed a reduction of lymphocyte populations and an increase of neutrophils in lung and then demonstrated the key role of neutrophil-mediated lung immunopathology in both mice and humans. Under severe conditions, neutrophils recruited by a chemokine-driven positive feedback produced elevated "fatal signature" proinflammatory genes and pathways related to neutrophil activation or releasing of granular content. In addition, we identified a new Cd177high cluster that is undergoing respiratory burst and Stfahigh cluster cells that may dampen antigen presentation upon infection. We also revealed the devastating effect of overactivated neutrophil by showing the highly enriched neutrophil extracellular traps in lung and a dampened B-cell function in either lung or spleen that may be attributed to arginine consumption by neutrophil. The current study helped our understanding of SARS-CoV-2-induced pneumonia and warranted the concept of neutrophil-targeting therapeutics in COVID-19 treatment. IMPORTANCE We demonstrated the single-cell landscape in lung and spleen upon SARS-CoV-2 infection in an acute severe disease mouse model that replicated human symptoms, including severe lung pathology and lymphopenia. Our comprehensive study revealed the key role of neutrophil-mediated lung immunopathology in SARS-CoV-2-induced severe pneumonia, which not only helped our understanding of COVID-19 but also warranted the concept of neutrophil targeting therapeutics in COVID-19 treatment.

4.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-332714

ABSTRACT

Objective: To explore the long-term effects of SARS-Cov-2 infection on the pulmonary function in convalescent COVID-19 patients of 6 to 9 months follow-up in Beijing, China. Methods: 64 cases of COVID-19 patients were recruited for the study, discharged from the Beijing Ditan Hospital, Capital Medical University for 6 to 9 months. COVID-19 patients were divided into mild, moderate and severe groups. The pulmonary function tests, the novel coronavirus antibody (IgM and IgG), chest CT and blood tests were investigated during follow-up. Results: 31.2% (20/64) patients had pulmonary ventilation dysfunction and 35.9% (23/64) had diffusion dysfunction. In the severe group, 56.50% (13/23) individuals showed decreased diffusion function. The diffusion dysfunction of severe group was significant decreased than the moderate (P=0.021). Among 56 cases, the positive rate of IgG titers was 73.2% (41/56). The result of chest CT showed 55.4% (31/56) cases in nodules, 44.6% (25/56) in strip-like changes, 37.5% (21/56) in ground glass shadow. Patients were tended to have ground glass changes in the severe group, while nodules in the moderate group. Conclusion: For the 6 to 9 months in convalescent COVID-19 patients, 56.50% (13/23) severe patients had pulmonary diffusion dysfunction. In the convalescent COVID-19 patients, especially those with severe illness, should have their pulmonary function tested regularly.

5.
J Virol ; : e0016922, 2022 Mar 28.
Article in English | MEDLINE | ID: covidwho-1765080

ABSTRACT

Severe acute respiratory syndrome coronavirus (SARS-CoV-1) and SARS-CoV-2 are highly pathogenic to humans and have caused pandemics in 2003 and 2019, respectively. Genetically diverse SARS-related coronaviruses (SARSr-CoVs) have been detected or isolated from bats, and some of these viruses have been demonstrated to utilize human angiotensin-converting enzyme 2 (ACE2) as a receptor and to have the potential to spill over to humans. A pan-sarbecovirus vaccine that provides protection against SARSr-CoV infection is urgently needed. In this study, we evaluated the protective efficacy of an inactivated SARS-CoV-2 vaccine against recombinant SARSr-CoVs carrying two different spike proteins (named rWIV1 and rRsSHC014S, respectively). Although serum neutralizing assays showed limited cross-reactivity between the three viruses, the inactivated SARS-CoV-2 vaccine provided full protection against SARS-CoV-2 and rWIV1 and partial protection against rRsSHC014S infection in human ACE2 transgenic mice. Passive transfer of SARS-CoV-2-vaccinated mouse sera provided low protection for rWIV1 but not for rRsSHC014S infection in human ACE2 mice. A specific cellular immune response induced by WIV1 membrane protein peptides was detected in the vaccinated animals, which may explain the cross-protection of the inactivated vaccine. This study shows the possibility of developing a pan-sarbecovirus vaccine against SARSr-CoVs for future preparedness. IMPORTANCE The genetic diversity of SARSr-CoVs in wildlife and their potential risk of cross-species infection highlight the necessity of developing wide-spectrum vaccines against infection of various SARSr-CoVs. In this study, we tested the protective efficacy of the SARS-CoV-2 inactivated vaccine (IAV) against two SARSr-CoVs with different spike proteins in human ACE2 transgenic mice. We demonstrate that the SARS-CoV-2 IAV provides full protection against rWIV1 and partial protection against rRsSHC014S. The T-cell response stimulated by the M protein may account for the cross protection against heterogeneous SARSr-CoVs. Our findings suggest the feasibility of the development of pan-sarbecovirus vaccines, which can be a strategy of preparedness for future outbreaks caused by novel SARSr-CoVs from wildlife.

6.
Signal Transduct Target Ther ; 7(1): 83, 2022 03 11.
Article in English | MEDLINE | ID: covidwho-1740428

ABSTRACT

SARS-CoV-2 induced marked lymphopenia in severe patients with COVID-19. However, whether lymphocytes are targets of viral infection is yet to be determined, although SARS-CoV-2 RNA or antigen has been identified in T cells from patients. Here, we confirmed that SARS-CoV-2 viral antigen could be detected in patient peripheral blood cells (PBCs) or postmortem lung T cells, and the infectious virus could also be detected from viral antigen-positive PBCs. We next prove that SARS-CoV-2 infects T lymphocytes, preferably activated CD4 + T cells in vitro. Upon infection, viral RNA, subgenomic RNA, viral protein or viral particle can be detected in the T cells. Furthermore, we show that the infection is spike-ACE2/TMPRSS2-independent through using ACE2 knockdown or receptor blocking experiments. Next, we demonstrate that viral antigen-positive T cells from patient undergone pronounced apoptosis. In vitro infection of T cells induced cell death that is likely in mitochondria ROS-HIF-1a-dependent pathways. Finally, we demonstrated that LFA-1, the protein exclusively expresses in multiple leukocytes, is more likely the entry molecule that mediated SARS-CoV-2 infection in T cells, compared to a list of other known receptors. Collectively, this work confirmed a SARS-CoV-2 infection of T cells, in a spike-ACE2-independent manner, which shed novel insights into the underlying mechanisms of SARS-CoV-2-induced lymphopenia in COVID-19 patients.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , COVID-19/metabolism , SARS-CoV-2/metabolism , T-Lymphocytes/metabolism , Animals , Caco-2 Cells , Chlorocebus aethiops , Humans , Vero Cells
7.
Front Public Health ; 10: 798005, 2022.
Article in English | MEDLINE | ID: covidwho-1731866

ABSTRACT

Background: Coronavirus disease 2019 (COVID-19) emerged in 2019 and has since caused a global pandemic. Since its emergence, COVID-19 has hugely impacted healthcare, including pediatrics. This study aimed to explore the current status and hotspots of pediatric COVID-19 research using bibliometric analysis. Methods: The Institute for Scientific Information Web of Science core collection database was searched for articles on pediatric COVID-19 to identify original articles that met the criteria. The retrieval period ranged from the creation of the database to September 20, 2021. A total of 3,561 original articles written in English were selected to obtain data, such as author names, titles, source publications, number of citations, author affiliations, and countries where the studies were conducted. Microsoft Excel (Microsoft, Redmond, WA) was used to create charts related to countries, authors, and institutions. VOSviewer (Center for Science and Technology Studies, Leiden, The Netherlands) was used to create visual network diagrams of keyword, author, and country co-occurrence. Results: We screened 3,561 publications with a total citation frequency of 30,528. The United States had the most published articles (1188 articles) and contributed the most with author co-occurrences. The author with the most published articles was Villani from the University of Padua, Italy. He also contributed the most co-authored articles. The most productive institution was Huazhong University of Science and Technology in China. The institution with the most frequently cited published articles was Shanghai Jiao Tong University in China. The United States cooperated most with other countries. Research hotspots were divided into two clusters: social research and clinical research. Besides COVID-19 and children, the most frequent keywords were pandemic (251 times), mental health (187 times), health (172 times), impact (148 times), and multisystem inflammatory syndrome in children (MIS-C) (144 times). Conclusion: Pediatric COVID-19 has attracted considerable attention worldwide, leading to a considerable number of articles published over the past 2 years. The United States, China, and Italy have leading roles in pediatric COVID-19 research. The new research hotspot is gradually shifting from COVID-19 and its related clinical studies to studies of its psychological and social impacts on children.


Subject(s)
COVID-19 , Pediatrics , Bibliometrics , COVID-19/complications , COVID-19/epidemiology , Child , China/epidemiology , Humans , Italy/epidemiology , Mental Health , SARS-CoV-2 , Systemic Inflammatory Response Syndrome , United States/epidemiology
8.
Emerg Microbes Infect ; 11(1): 902-913, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-1730557

ABSTRACT

The immune memory of over 400 million COVID-19 convalescents is not completely understood. In this integrated study, we recorded the post-acute sequelae symptoms and tested the immune memories, including circulating antibodies, memory B cell, and memory CD4 or CD8 T cell responses of a cohort of 65 COVID-19 patients over 1-year after infection. Our data show that 48% of them still have one or more sequelae symptoms and all of them maintain at least one of the immune components. The chances of having sequelae symptoms or having better immune memory are associated with peak disease severity. We did four-time points sampling per subject to precisely understand the kinetics of durability of SARS-CoV-2 circulating antibodies. We found that the RBD IgG levels likely reach a stable plateau at around 6 months, albeit it is waning at the first 6 months after infection. At 1-year after infection, more than 90% of the convalescents generated memory CD4 or CD8 T memory responses, preferably against the SARS-CoV-2 M peptide pool. The convalescents also have polyfunctional and central memory T cells that could provide rapid and efficient response to SARS-CoV-2 re-infection. Based on this information, we assessed the immune protection against the Omicron variant and concluded that convalescents should still induce effective T cell immunity against the Omicron. By studying the circulating antibodies and memory B or T cell responses to SARS-CoV-2 in an integrated manner, our study provides insight into the understanding of protective immunity against diseases caused by secondary SARS-CoV-2 infection.


Subject(s)
COVID-19 , Antibodies, Viral , Humans , Immunity, Cellular , Longitudinal Studies , SARS-CoV-2
9.
Health Aff (Millwood) ; 41(3): 445-453, 2022 03.
Article in English | MEDLINE | ID: covidwho-1690679

ABSTRACT

Evidence for the effectiveness of masking on SARS-CoV-2 transmission at the individual level has accumulated, but the additional benefit of community-level mandates is less certain. In this observational study of matched cohorts from 394 US counties between March 21 and October 20, 2020, we estimated the association between county-level public masking mandates and daily COVID-19 case incidence. On average, the daily case incidence per 100,000 people in masked counties compared with unmasked counties declined by 23 percent at four weeks, 33 percent at six weeks, and 16 percent across six weeks postintervention. The beneficial effect varied across regions of different population densities and political leanings. The most concentrated effects of masking mandates were seen in urban counties; the benefit of the mandates was potentially stronger within Republican-leaning counties. Although benefits were not equally distributed in all regions, masking mandates conferred benefit in reducing community case incidence during an early period of the COVID-19 pandemic.


Subject(s)
COVID-19 , COVID-19/epidemiology , COVID-19/prevention & control , Government , Humans , Incidence , Pandemics/prevention & control , SARS-CoV-2 , United States/epidemiology
10.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-325161

ABSTRACT

Objective: To explore the psychological health status of middle school students in China during the recent epidemic outbreak of “Novel Coronavirus Pneumonia” (NCP) and its influencing factors, and to provide a basis and suggestions for the adjustment of mental health of middle school students during the epidemic. Methods: : A total of 2,007 middle school students were randomly selected nationwide to fill out a questionnaire. The questionnaire included basic personal and family information, life status and family relations during the epidemic, attitudes and pressures in the face of the epidemic, created by Chinese professor Zung. The anxiety self-assessment scale (SAS) compiled by SPSS statistical analysis software was used for data analysis to explore the changes in mental health during the epidemic. Results: : Of the 2,007 valid questionnaires, according to the data using the self-rating anxiety scale, 424 students had anxiety, accounting for 21.1% of the total number;anxiety level of boys was higher than that of girls, and the anxiety level increased as the grade level increased. The student's personality, grade level, problem-solving methods, awareness and attention to the epidemic, parents' educational background, marital status, and family economic status all had an impact on the student's psychological status during the epidemic. Conclusion: The Novel Coronavirus Pneumonia epidemic has a great impact on the mental health of some middle school students. Family, school and social departments should pay attention to this phenomenon, care for their mental health, and take reasonable measures to actively intervene.

11.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-323765

ABSTRACT

Background: Coronavirus disease 2019 (COVID-19) has affected over 100 countries thus far. The increasing number of patients might lead to enormous changes in psychological status of medical staff. Aims: The aim of this study was to understand the psychological status of medical staff during the COVID-19 outbreak. Method: Medical staff working in hospitals in Wuhan and the Yangtze River Delta were invited to complete an online questionnaire, which was composed of basic demographic data, the Athens Insomnia Scale (AIS) for sleep disturbances, the Generalized Anxiety Disorder (GAD-7) for anxiety, and the Self-Rating Depression Scale (SDS) for depressive symptoms. Results: Among the 1225 invited medical staff, 686 participants (64 males, 9.33% and 622 females, 90.67%;average age 33.13±7.82 years) responded to the survey (response rate was 56.00%). 482 (67.35%) respondents reported sleep disturbances, 224 (32.65%) reported anxiety and 204 (29.74%) reported depressive symptoms. Multivariable linear regression analysis showed that occupation (doctor), department (respiratory, ICU), workplace (areas in Wuhan), marital status (married), and medical history (anxiety, depression or sleep disorders) were significantly correlated with AIS, GAD-7 and SDS scores (P<0.01). Conclusions: COVID-19 imposes a significant burden on mental health of medical staff. Gender, marital status, occupation, department, workplace and a specific medical history were major influencing factors for sleep disorders, anxiety and depressive symptoms among these front-line medical staff. More attention needs to be paid to the psychological care of medical staff during the COVID-19 pandemic.Funding Statement: None.Declaration of Interests: The authors declare that they have no competing interests.Ethics Approval Statement: The ethics committee of Shanghai General Hospital approved this study, under the principles of voluntary participation, anonymity and strict confidentiality. When participants chose to complete the survey, their consent was presumed.

12.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-323540

ABSTRACT

Background: COVID-19, a worldwideinfectious disease, has killed more than 420000 people, whichis extremely harmful. Methods: In this single-center retrospective study, we included the novel coronavirus pneumonia confirmed in our hospital. This study collected the basic information andclinical examination features. Results: The enrolled 704 patients were affirmed infected with 2019-nCoV by the test of throat swabs. There are 334 men and 369 women, and gender, age, combined with basic diseasesare distinct in diverse disease classification (p<0.05). From the symptom analysis, the proportion of fever over 38 degrees, dyspnea, fatigue, poor appetite and other symptoms is diverse in different types of diseases (p<0.05). As the severity of the disease increases, the median lymphocyte count decreases, C-reactive protein increase, erythrocyte sedimentation rateincrease, albumin decrease, pleural effusion increase, D-Dimer and NT-proBNP increase significantly (p<0.05).As the disease severity increases, the average value of MuLBSTA score obviously ascend (p<0.05), MuLBSTA scoring system predicts novel coronavirus pneumonia patients' prognosis is still insufficient, and may require additional indicators including anorexia, fatigue, C reactive protein, etc (p<0.05). Conclusion: The MuLBSTA evaluation system has certain value for the evaluation of the disease, but it needs to be improved.

13.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-309023

ABSTRACT

Background: The COVID-19 pandemic is a major health crisis has led to adverse mental health consequences in the general public, medical staff, and individual in self isolation. In order to stop transmission of the virus and save lives, Fangcang shelter hospitals were developed and used for the first time in China. However, there is no research on mental health problems in Fangcang shelter hospitals patients during the COVID-19 outbreak. The aim of this study was to survey the prevalence and major influencing factors of anxiety, depression among the hospitalized Coronavirus Disease 2019 (COVID-19) cases in Fangcang shelter hospital. Methods From February 23rd, 2020, to February 26th, 2020, we obtained the information of demographic data, clinical symptoms, and assessed the mental health status, sleep quality by using an online questionnaire including self-rating anxiety scale (SAS), self-rating depressive scale (SDS) and pittsburgh sleep quality index (PSQI) at Jianghan Fangcang shelter hospital. We assessed the prevalence of anxiety, depression symptoms and poor sleep quality via the scores of SAS, SDS and PSQI. We explored the influencing factors of anxiety and depression in COVID-19 patients using multivariable logistic regression models. Results We collected data from 307 COVID-19 patients in Jianghan Fangcang shelter hospital. The prevalence of anxiety, depression symptoms were 18.6% and 13.4%, respectively. Poor Sleep quality, number of current physical symptoms ≥ 2 were independent risk factors for anxiety symptoms ( P  < 0.05);female, family member confirmed COVID-19, number of current physical symptoms ≥ 2 were independent risk factors for depression symptoms ( P  < 0.05). PSQI scores were significant positively associate with SAS scores and SDS scores ( P ༜ 0.05). Conclusions Anxiety and depression are common among the COVID-19 patients in Fangcang shelter hospital. Those with more current physical symptoms, poor sleep quality are more likely to have anxiety. Females, those with their family members diagnosed with COVID-19, more current physical symptoms are more vulnerable to depression symptom. Our findings can be used to formulate targeted psychological interventions to reduce adverse psychological impacts in Fangcang shelter hospital during the outbreak of epidemic disease in the future.

14.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-308348

ABSTRACT

Background: and objective: Coronavirus disease (COVID-19) is currently an urgent global issue, but we cannot ignore the impact of influenza A since there is an overlap of infection time and region and similar clinical manifestations and chest computed tomography (CT) images for influenza A and COVID-19 infections. We compared patients who had a COVID-19 infection and co-infection with the influenza A virus. Methods: : We retrospectively reviewed patients who met the inclusion criteria for this study. Results: : There were 213 patients included in this study, of whom 106 were females and 107 were males, with a median age of 63 years. All patients were diagnosed with COVID-19 and were subsequently divided into influenza positive (n = 97) and influenza negative (n = 116) groups according to the serum test results for the influenza A IgM antibody. The two groups had similar symptoms, outcomes, CT manifestation and CT scores, except for lymphadenopathy (6.2% in the influenza positive group vs. 14.7% in the negative group, P = 0.047). However, in the subgroup analysis, male or younger patients (age <= 60 years) in the influenza negative group had higher CT scores than patients in the influenza positive group (P < 0.05). Conclusions: : COVID-19 patients who had co-infection with the influenza A virus showed similar symptoms, outcomes, CT manifestation and CT scores to influenza negative patients. However, male patients and younger patients had higher CT scores in the influenza negative group.

15.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-313728

ABSTRACT

We construct an economic model of epidemiology, in which agents' economic decisions affect epidemic dynamics and vice versa. Agents are randomly matched and trade goods in pairwise meetings. The meeting rate increases in agents' search efforts, and the pathogen can be transmitted from infected agents to susceptible agents in meetings. We calibrate the model to the COVID-19 pandemic in the U.S. The model shows that unless an instrument, such as a vaccine, entirely stops new infections, the pandemic can be persistent due to the non-lasting property of immunity. Output drops because agents search less due to the threat of infections, and trade volumes in each meeting fall. We also conduct counterfactual analyses to study the effects of monetary policy, preventive measures, persistence of immunity, and lockdowns on epidemic dynamics and economic performance.

16.
Pharmacol Res ; 176: 106083, 2022 02.
Article in English | MEDLINE | ID: covidwho-1638968

ABSTRACT

The pathogenic hyper-inflammatory response has been revealed as the major cause of the severity and death of the Corona Virus Disease 2019 (COVID-19). Xuanfei Baidu Decoction (XFBD) as one of the "three medicines and three prescriptions" for the clinically effective treatment of COVID-19 in China, shows unique advantages in the control of symptomatic transition from moderate to severe disease states. However, the roles of XFBD to against hyper-inflammatory response and its mechanism remain unclear. Here, we established acute lung injury (ALI) model induced by lipopolysaccharide (LPS), presenting a hyperinflammatory process to explore the pharmacodynamic effect and molecular mechanism of XFBD on ALI. The in vitro experiments demonstrated that XFBD inhibited the secretion of IL-6 and TNF-α and iNOS activity in LPS-stimulated RAW264.7 macrophages. In vivo, we confirmed that XFBD improved pulmonary injury via down-regulating the expression of proinflammatory cytokines such as IL-6, TNF-α and IL1-ß as well as macrophages and neutrophils infiltration in LPS-induced ALI mice. Mechanically, we revealed that XFBD treated LPS-induced acute lung injury through PD-1/IL17A pathway which regulates the infiltration of neutrophils and macrophages. Additionally, one major compound from XFBD, i.e. glycyrrhizic acid, shows a high binding affinity with IL17A. In conclusion, we demonstrated the therapeutic effects of XFBD, which provides the immune foundations of XFBD and fatherly support its clinical applications.


Subject(s)
Acute Lung Injury/drug therapy , Drugs, Chinese Herbal/pharmacology , Interleukin-17/metabolism , Macrophages/drug effects , Neutrophils/drug effects , Programmed Cell Death 1 Receptor/metabolism , Signal Transduction/drug effects , Acute Lung Injury/metabolism , Animals , COVID-19/drug therapy , COVID-19/metabolism , Cell Line , China , Cytokines/metabolism , Leukocyte Count/methods , Macrophages/metabolism , Male , Mice , Mice, Inbred C57BL , Neutrophils/metabolism , RAW 264.7 Cells
17.
Annals of GIS ; : 1-12, 2022.
Article in English | Taylor & Francis | ID: covidwho-1625782
18.
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
19.
Transactions in GIS : TG ; 2021.
Article in English | EuropePMC | ID: covidwho-1564272

ABSTRACT

The second COVID‐19 outbreak in Beijing was controlled by non‐pharmaceutical interventions, which avoided a second pandemic. Until mass vaccination achieves herd immunity, cities are at risk of similar outbreaks. It is vital to quantify and simulate Beijing's non‐pharmaceutical interventions to find effective intervention policies for the second outbreak. Few models have achieved accurate intra‐city spatio‐temporal epidemic spread simulation, and most modeling studies focused on the initial pandemic. We built a dynamic module of infected case movement within the city, and established an urban spatially epidemic simulation model (USESM), using mobile phone signaling data to create scenarios to assess the impact of interventions. We found that: (1) USESM simulated the transmission process of the epidemic within Beijing;(2) USESM showed the epidemic curve and presented the spatial distribution of epidemic spread on a map;and (3) to balance resources, interventions, and economic development, nucleic acid testing intensity could be increased and restrictions on human mobility in non‐epidemic areas eased.

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