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1.
Vaccines ; 10(4):544, 2022.
Article in English | MDPI | ID: covidwho-1776369

ABSTRACT

Background: Vaccination is the most effective method for the prevention of COVID-19. However, willingness to be vaccinated is not consistent. This study aimed to explore vaccine cognition, risk perception, and health behavior of COVID-19 in China. Methods: A cross-sectional survey was performed in Guangdong province, China, including demographic characteristics, health status and preventive behaviors, cognition of COVID-19 vaccination, and the health belief model (HBM). Results: A total of 1640 participants were recruited. The main access to information about COVID-19 and vaccination as through official news and broadcasts (67.3%), social network software (58.7%), and professional popularization (46.2%). The precautions taken were wearing a mask (67.0%) and avoiding gathering together (71.3%). COVID-19 vaccination acceptability was different among different age groups and educational levels (p < 0.001). The major reasons for accepting vaccination included that it was an effective way to prevent COVID-19 (61.8%) and that it was required by working units/schools (51.1%). The fitting effect indexes of the (HBM) Model 2 showed better fitting than those of Model 1. In Model 2, perceived benefits (OR = 3.13, 95% CI: 1.79–5.47), cues to action (OR = 2.23, 95% CI: 1.60–3.11), and different occupations (OR = 1.13, 95% CI: 1.04–1.23) were positively correlated with vaccine acceptance;while perceived susceptibility (OR = 0.47, 95% CI: 0.30–0.74) and perceived barriers (OR = 0.44, 95% CI: 0.29–0.69) were negative factors associated with vaccine acceptance. Conclusion: Different sociodemographic characteristics lead to differences in acceptance of vaccination, and the publicity and credibility of government play an indispensable role in epidemic control. The establishment of the HBM further predicted that perceived susceptibility to COVID-19, benefits of vaccination, barriers of cognition, and cue to action were the influencing factors of intention and health behaviors.

2.
J Virol ; 96(7): e0013622, 2022 Apr 13.
Article in English | MEDLINE | ID: covidwho-1745828

ABSTRACT

Viruses have evolved diverse strategies to hijack the cellular gene expression system for their replication. The poly(A) binding proteins (PABPs), a family of critical gene expression factors, are viruses' common targets. PABPs act not only as a translation factor but also as a key factor of mRNA metabolism. During viral infections, the activities of PABPs are manipulated by various viruses, subverting the host translation machinery or evading the cellular antiviral defense mechanism. Viruses harness PABPs by modifying their stability, complex formation with other translation initiation factors, or subcellular localization to promote viral mRNAs translation while shutting off or competing with host protein synthesis. For the past decade, many studies have demonstrated the PABPs' roles during viral infection. This review summarizes a comprehensive perspective of PABPs' roles during viral infection and how viruses evade host antiviral defense through the manipulations of PABPs.


Subject(s)
COVID-19 , Virus Diseases , Antiviral Agents , Humans , Poly(A)-Binding Proteins/genetics , Poly(A)-Binding Proteins/metabolism , Protein Binding , Protein Biosynthesis , RNA, Messenger/genetics , SARS-CoV-2
3.
EuropePMC;
Preprint in English | EuropePMC | ID: ppcovidwho-328744

ABSTRACT

The current global epidemiology of COVID-19 is now characterized by the emergence and rapid spread of the SARS-CoV-2 Omicron variant on a global scale 1,2 . Despite the variant’s prompt predominance, there remain knowledge gaps in its origin and evolution history 3–6 . Here, we show that Omicron lineage SARS-CoV-2 is characterized by the feature of chimera. It was generated by genomic recombination of two early PANGO lineages of SARS-CoV-2. In the recombination event, strains with medium or high circulating intensity like SARS-CoV-2/human/USA/COR-21-434196/2021 belonging to PANGO lineage BA.1 provided the fundamental genome and served as the major parents, while the rare lineage strains like SARS-CoV-2/human/IRN/Ir-3/2019 belonging to B.35, as the minor parents, hybridized their genomic fractions into the major genomes at position 21593-23118nt. This recombination event results in 22 amino acid residue substitutions for the variant of Omicron, including 16 in the pivotal RBD of the spike protein. These substitutions have led to some subtle variations in the spatial structure and the affinity to hACE2 receptor of the spike protein 7,8 , thereby raising concerns about the effectiveness of available vaccines and antibody therapeutics 9–12 . The global spread and explosive growth of the SARS-CoV-2 in human population increase opportunities for future recombination 13–15 .

4.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-325038

ABSTRACT

In order to identify the clinical characteristics of patients with Corona Virus Disease 2019 (COVID-19) and find out the characteristic effects of 2019 New Coronavirus (SARS-CoV-2) infection on changes in clinical and laboratory data, we analyzed the medical records of 80 suspected cases who admitted in the national designated hospital due to the relevant clinical manifestations of SARS-CoV-2 infection from January 22 to February 13, 2020. 62 (77.5%) confirmed cases and 18 (22.5%) negative cases were confirmed by SARS-CoV-2 nucleic acid test. Epidemiological investigation and statistical analysis were carried out on the clinical and laboratory data of all suspected cases of COVID-19, the specific indicators were found, and the clinical characteristics of COVID-19 were described. Compared with the patients with negative nucleic acid test, the patients with positive nucleic acid test showed shorter time of onset of symptoms, higher plasma CO 2 level, lower eosinophil ratio, lower platelet count and hematocrit, lower serum sodium level, higher serum creatinine, higher blood urea and plasma albumin levels (all P <0.05). Our results might provide some suggestions in diagnosis, clinical treatment and prevention for COVID-19.

5.
Front Immunol ; 12: 769442, 2021.
Article in English | MEDLINE | ID: covidwho-1686473

ABSTRACT

The prevention of the COVID-19 pandemic is highly complicated by the prevalence of asymptomatic and recurrent infection. Many previous immunological studies have focused on symptomatic and convalescent patients, while the immune responses in asymptomatic patients and re-detectable positive cases remain unclear. Here we comprehensively analyzed the peripheral T-cell receptor (TCR) repertoire of 54 COVID-19 patients in different courses, including asymptomatic, symptomatic, convalescent, and re-detectable positive cases. We identified a set of V-J gene combinations characterizing the upward immune responses through asymptomatic and symptomatic courses. Furthermore, some of these V-J combinations could be awakened in the re-detectable positive cases, which may help predict the risk of recurrent infection. Therefore, TCR repertoire examination has the potential to strengthen the clinical surveillance and the immunotherapy development for COVID-19.


Subject(s)
COVID-19/pathology , Immunoglobulin J-Chains/genetics , Immunoglobulin Variable Region/genetics , Receptors, Antigen, T-Cell/genetics , SARS-CoV-2/immunology , T-Lymphocytes/immunology , Adaptive Immunity/genetics , Adaptive Immunity/immunology , Adult , Aged , Asymptomatic Infections , COVID-19/immunology , Female , Gene Expression/genetics , Histocompatibility Antigens Class I/genetics , Humans , Male , Middle Aged , Receptors, Antigen, T-Cell/immunology , Severity of Illness Index , Young Adult
6.
Int J Environ Res Public Health ; 19(3)2022 01 29.
Article in English | MEDLINE | ID: covidwho-1667144

ABSTRACT

Many countries adopted lockdown measures to curb the spread of the outbreak in 2020, while information about COVID-19 has dominated various media outlets, which has led to information overload for people. However, previous research has mainly focused on cancer information overload and the corresponding consequence, and failed to examine its adverse effects in the context of major public health events. Based on the Frustrate Aggression Theory and the Scapegoat Theory, the present study established a moderated mediation model to investigate the emotional and behavioral outcomes of COVID-19 information overload. The mediating role of depression/anxiety in the association between COVID-19 information overload and cyber aggression, as well as the moderating role of Confucian responsibility thinking, were tested. This model was examined with 1005 Chinese people (mean age = 26.91 years, SD = 9.94) during the COVID-19 outbreak. Mediation analyses revealed that COVID-19 information overload was positively related to cyber aggression, depression, and anxiety, parallelly and partially mediated this relationship. Moderated mediation analyses further indicated that Confucian responsibility thinking not only moderated the direct link between COVID-19 information overload and cyber aggression, with the effect being significant only for people with a low level of Confucian responsibility thinking, but also moderated the relationship between COVID-19 information overload and depression/anxiety respectively, with the associations being much more potent for individuals with low levels of Confucian responsibility thinking. These findings have the potential to inform the development of prevention and intervention programs designed to reduce the negative emotions and cyber aggression associated with information overload in public health events.


Subject(s)
COVID-19 , Pandemics , Adult , Aggression , Anxiety/epidemiology , Communicable Disease Control , Depression/epidemiology , Humans , SARS-CoV-2
7.
BMC Med ; 20(1): 13, 2022 01 18.
Article in English | MEDLINE | ID: covidwho-1639199

ABSTRACT

BACKGROUND: Recaticimab (SHR-1209, a humanized monoclonal antibody against PCSK9) showed robust LDL-C reduction in healthy volunteers. This study aimed to further assess the efficacy and safety of recaticimab in patients with hypercholesterolemia. METHODS: In this randomized, double-blind, placebo-controlled phase 1b/2 trial, patients receiving stable dose of atorvastatin with an LDL-C level of 2.6 mmol/L or higher were randomized in a ratio of 5:1 to subcutaneous injections of recaticimab or placebo at different doses and schedules. Patients were recruited in the order of 75 mg every 4 weeks (75Q4W), 150Q8W, 300Q12W, 150Q4W, 300Q8W, and 450Q12W. The primary endpoint was percentage change in LDL-C from the baseline to end of treatment (i.e., at week 16 for Q4W and Q8W schedule and at week 24 for Q12W schedule). RESULTS: A total of 91 patients were enrolled and received recaticimab and 19 received placebo. The dose of background atorvastatin in all 110 patients was 10 or 20 mg/day. The main baseline LDL-C ranged from 3.360 to 3.759 mmol/L. The least-squares mean percentage reductions in LDL-C from baseline to end of treatment relative to placebo for recaticimab groups at different doses and schedules ranged from -48.37 to -59.51%. No serious treatment-emergent adverse events (TEAEs) occurred. The most common TEAEs included upper respiratory tract infection, increased alanine aminotransferase, increased blood glucose, and increased gamma-glutamyltransferase. CONCLUSION: Recaticimab as add-on to moderate-intensity statin therapy significantly and substantially reduced the LDL-C level with an infrequent administration schedule (even given once every 12 weeks), compared with placebo. TRIAL REGISTRATION: ClinicalTrials.gov , number NCT03944109.


Subject(s)
Hypercholesterolemia , Antibodies, Monoclonal, Humanized/adverse effects , Double-Blind Method , Humans , Hydroxymethylglutaryl-CoA Reductase Inhibitors/administration & dosage , Hypercholesterolemia/drug therapy , Treatment Outcome
8.
Cell Death Differ ; 2022 Jan 08.
Article in English | MEDLINE | ID: covidwho-1612182

ABSTRACT

A recent mutation analysis suggested that Non-Structural Protein 6 (NSP6) of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a key determinant of the viral pathogenicity. Here, by transcriptome analysis, we demonstrated that the inflammasome-related NOD-like receptor signaling was activated in SARS-CoV-2-infected lung epithelial cells and Coronavirus Disease 2019 (COVID-19) patients' lung tissues. The induction of inflammasomes/pyroptosis in patients with severe COVID-19 was confirmed by serological markers. Overexpression of NSP6 triggered NLRP3/ASC-dependent caspase-1 activation, interleukin-1ß/18 maturation, and pyroptosis of lung epithelial cells. Upstream, NSP6 impaired lysosome acidification to inhibit autophagic flux, whose restoration by 1α,25-dihydroxyvitamin D3, metformin or polydatin abrogated NSP6-induced pyroptosis. NSP6 directly interacted with ATP6AP1, a vacuolar ATPase proton pump component, and inhibited its cleavage-mediated activation. L37F NSP6 variant, which was associated with asymptomatic COVID-19, exhibited reduced binding to ATP6AP1 and weakened ability to impair lysosome acidification to induce pyroptosis. Consistently, infection of cultured lung epithelial cells with live SARS-CoV-2 resulted in autophagic flux stagnation, inflammasome activation, and pyroptosis. Overall, this work supports that NSP6 of SARS-CoV-2 could induce inflammatory cell death in lung epithelial cells, through which pharmacological rectification of autophagic flux might be therapeutically exploited.

9.
Front Cell Infect Microbiol ; 11: 791660, 2021.
Article in English | MEDLINE | ID: covidwho-1599571

ABSTRACT

The appearance and magnitude of the immune response and the related factors correlated with SARS-CoV-2 vaccination need to be defined. Here, we enrolled a prospective cohort of 52 participants who received two doses of inactivated vaccines (BBIBP-CorV). Their serial plasma samples (n = 260) over 2 months were collected at five timepoints. We measured antibody responses (NAb, S-IgG and S-IgM) and routine blood parameter. NAb seroconversion occurred in 90.7% of vaccinated individuals and four typical NAb kinetic curves were observed. All of the participants who seroconverted after the first dose were females and had relatively high prevaccine estradiol levels. Moreover, those without seroconversion tended to have lower lymphocyte counts and higher serum SAA levels than those who experienced seroconversion. The NAb titers in young vaccine recipients had a significantly higher peak than those in elderly recipients. S-IgG and S-IgM dynamics were accompanied by similar trends in NAb. Here, we gained insight into the dynamic changes in NAbs and preliminarily explored the prevaccine blood parameters related to the kinetic subclasses, providing a reference for vaccination strategies.


Subject(s)
COVID-19 Vaccines , COVID-19 , Aged , Antibodies, Neutralizing , Antibodies, Viral , Antibody Formation , Female , Healthy Volunteers , Humans , Prospective Studies , SARS-CoV-2 , Vaccines, Inactivated
10.
Infect Dis Ther ; 11(1): 405-422, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1559110

ABSTRACT

INTRODUCTION: We aimed to evaluate the safety, tolerability, pharmacokinetics, and immunogenicity of a single dose of LY-CovMab in Chinese healthy adults. METHODS: We conducted a phase 1, randomized, dose-escalation, placebo-controlled trial in 42 volunteers, 18-45 years of age, and 40 out of 42 received a single dose of LY-CovMab or placebo with LY-CovMab at a dose of 30 mg, 150 mg, 600 mg, 1200 mg, and 2400 mg. There were ten subjects in each group receiving LY-CovMab or placebo in a 4:1 ratio with the exception that the 30 mg group had two subjects both receiving LY-CovMab. RESULTS: Among the 42 randomized participants, 40 received an injection with 32 administered LY-CovMab and 8 administered placebo. A total of 18 drug-related treatment-emergent adverse events (TEAEs) were reported in 12 subjects (30.0%), including protein urine present (25%, 10/40) and blood creatinine increased (7.5%, 3/40). The incidence of drug-related TEAE in each dosage group was as follows: 150 mg (28.6%, 2/7), 600 mg (25%, 2/8), 1200 mg (14.3%, 1/7), 2400 mg (50%, 4/8), and placebo (37.5%, 3/8). All drug-related TEAEs were grade 1, and most of them were recovering/resolving or recovered/resolved without taking action. The serum exposure of LY-CovMab (Cmax, AUC0-last, AUC0-inf) after intravenous infusion increased in an approximately proportional manner as the dose increased from 150 to 2400 mg. The elimination half-life (t1/2) value did not differ among different dose cohorts and was estimated to be around 28.5 days. CONCLUSIONS: A single dose of LY-CovMab was shown to be safe and well tolerated in Chinese healthy adults. The pharmacokinetic (PK) profiles of LY-CovMab in healthy adults showed typical monoclonal antibody distribution and elimination characteristics. LY-CovMab demonstrated dose proportionality. TRIAL REGISTRATION: ClinicalTrial.gov Identifier NCT04973735.

12.
Front Cell Infect Microbiol ; 11: 741147, 2021.
Article in English | MEDLINE | ID: covidwho-1512020

ABSTRACT

The coronavirus disease 2019 (COVID-19) has caused and is still causing tremendous damage to the global economy and human health. Qualitative reverse transcription-PCR (RT-qPCR) is the golden standard for COVID-19 test. However, the SARS-CoV-2 variants may not only make vaccine less effective but also evade RT-qPCR test. Here we suggest an innovative primer design strategy for the RT-qPCR test of SARS-CoV-2. The principle is that the primers should be designed based on both the nucleic acid sequence and the structure of the protein encoded. The three nucleotides closest to the 3' end of the primer should be the codon which encodes the tryptophan in the structure core. Based on this principle, we designed a pair of primers targeting the nucleocapsid (N) gene. Since tryptophan is encoded by only one codon, any mutation that occurs at this position would change the amino acid residue, resulting in an unstable N protein. This means that this kind of SARS-CoV-2 variant could not survive. In addition, both our data and previous reports all indicate that the mutations occurring at other places in the primers do not significantly affect the RT-qPCR result. Consequently, no SARS-CoV-2 variant can escape detection by the RT-qPCR kit containing the primers designed based on our strategy.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Mutation , RNA, Viral/genetics , Real-Time Polymerase Chain Reaction , Sensitivity and Specificity
13.
World J Diabetes ; 12(10): 1789-1808, 2021 Oct 15.
Article in English | MEDLINE | ID: covidwho-1478298

ABSTRACT

BACKGROUND: Previous studies have shown that diabetes mellitus is a common comorbidity of coronavirus disease 2019 (COVID-19), but the effects of diabetes or anti-diabetic medication on the mortality of COVID-19 have not been well described. AIM: To investigate the outcome of different statuses (with or without comorbidity) and anti-diabetic medication use before admission of diabetic after COVID-19. METHODS: In this multicenter and retrospective study, we enrolled 1422 consecutive hospitalized patients from January 21, 2020, to March 25, 2020, at six hospitals in Hubei Province, China. The primary endpoint was in-hospital mortality. Epidemiological material, demographic information, clinical data, laboratory parameters, radiographic characteristics, treatment and outcome were extracted from electronic medical records using a standardized data collection form. Most of the laboratory data except fasting plasma glucose (FPG) were obtained in first hospitalization, and FPG was collected in the next day morning. Major clinical symptoms, vital signs at admission and comorbidities were collected. The treatment data included not only COVID-19 but also diabetes mellitus. The duration from the onset of symptoms to admission, illness severity, intensive care unit (ICU) admission, and length of hospital stay were also recorded. All data were checked by a team of sophisticated physicians. RESULTS: Patients with diabetes were 10 years older than non-diabetic patients [(39 - 64) vs (56 - 70), P < 0.001] and had a higher prevalence of comorbidities such as hypertension (55.5% vs 21.4%, P < 0.001), coronary heart disease (CHD) (9.9% vs 3.5%, P < 0.001), cerebrovascular disease (CVD) (3% vs 2.2%, P < 0.001), and chronic kidney disease (CKD) (4.7% vs 1.5%, P = 0.007). Mortality (13.6% vs 7.2%, P = 0.003) was more prevalent among the diabetes group. Further analysis revealed that patients with diabetes who took acarbose had a lower mortality rate (2.2% vs 26.1, P < 0.01). Multivariable Cox regression showed that male sex [hazard ratio (HR) 2.59 (1.68 - 3.99), P < 0.001], hypertension [HR 1.75 (1.18 - 2.60), P = 0.006), CKD [HR 4.55 (2.52-8.20), P < 0.001], CVD [HR 2.35 (1.27 - 4.33), P = 0.006], and age were risk factors for the COVID-19 mortality. Higher HRs were noted in those aged ≥ 65 (HR 11.8 [4.6 - 30.2], P < 0.001) vs 50-64 years (HR 5.86 [2.27 - 15.12], P < 0.001). The survival curve revealed that, compared with the diabetes only group, the mortality was increased in the diabetes with comorbidities group (P = 0.009) but was not significantly different from the non-comorbidity group (P = 0.59). CONCLUSION: Patients with diabetes had worse outcomes when suffering from COVID-19; however, the outcome was not associated with diabetes itself but with comorbidities. Furthermore, acarbose could reduce the mortality in diabetic.

14.
Int J Ment Health Addict ; : 1-11, 2021 Oct 12.
Article in English | MEDLINE | ID: covidwho-1465898

ABSTRACT

We noticed an unusual increase of aged adults in first-episode schizophrenia in January and February 2020 since the outbreak of COVID-19. This retrospective study aims to statistically validate this observation and find potential risk factors, if applicable. The demographics of schizophrenia in outpatients (both first-episode and follow-up) from January to March 2020 (36,624 records) and similar periods of 2017-2019 (114,141 records) were analyzed and compared to minimize seasonal influence. Limited personal information (age, gender, approximate residence) was investigated to find risk factors. After considering seasonal factors such as the Spring festival, the age of the first-episode schizophrenia was significantly increased in January (46.60 ± 15.14) and February (51.53 ± 14.74) but went back to normal in March 2020 (38.89 ± 14.59), compared with similar periods from 2017 to 2019 (Jan., 40.77 ± 15.26; Feb., 39.69 ± 15.10; Mar., 42.04 ± 15.83). Meanwhile, a slight but not significant change was found in the distribution of gender and approximate residence (urban/suburb). Our data supported that risk of first-episode schizophrenia in aged adults increased during the COVID-19 outbreak, which is consistent with the fact that COVID-19 is more lethal to elders. Public healthcare should prepare in advance for potential risks in public mental health, especially for elders.

15.
Vaccines (Basel) ; 9(10)2021 Sep 28.
Article in English | MEDLINE | ID: covidwho-1444339

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has developed variants escaping neutralization antibody immunity established against the original virus. An understanding of broad-spectrum adaptive immunity, including CD8+ T cell immunity to wide range of epitopes, could help translational efforts to improve coronavirus disease 2019 (COVID-19) prevention and therapy. However, there have been few direct studies in which such immunity exists in a population. METHODS: We selected SARS-CoV-2-conserved structural peptides that are not prone to mutation as antigens for broad-spectrum CD8+ T cell immunity. Peripheral blood mononuclear cells (PBMCs) from unexposed healthy donors were stimulated with these peptides in vitro and CD8+ T cell-specific response was monitored. The conserved peptide-specific CD8+ T cells were sorted for T cell receptor (TCR) repertoire sequencing. The presence of specific complementary determining region 3 (CDR3) clones was analyzed in a healthy cohort. RESULTS: For each structural protein, including S, E, M, N, the conserved peptides could potentially provide the largest number of major histocompatibility complex-I (MHC-I) epitopes in the Oriental and Caucasian populations. For conserved peptides from spike (S), envelope (E), membrane (M), nucleocapsid (N) proteins, we found that there were no cross-reactive memory T cells in the unexposed individuals. Instead, their T cells contain naïve TCR repertoire recognizing these conserved peptides. Using TCR sequencing and CDR3 clustering for the conserved peptides specific T cells, we found that the recovered patients had a higher proportion of TCR repertoire similar with that of specific CD8+ T cells in unexposed individuals. Meanwhile, CDR3 clones of the above T cells were widely present in the healthy population. CONCLUSIONS: This study provides evidence of broad-spectrum SARS-CoV-2 specific CD8+ TCR repertoire in unexposed healthy population, which is implicated in the development and implementation of broad-spectrum vaccines against COVID-19.

17.
J Vet Sci ; 22(5): e72, 2021 Sep.
Article in English | MEDLINE | ID: covidwho-1403958

ABSTRACT

It has been speculated that bats serve as reservoirs of a huge variety of emerging coronaviruses (CoVs) that have been responsible for severe havoc in human health systems as well as negatively affecting human economic and social systems. A prime example is the currently active severe acute respiratory syndrome (SARS)-CoV2, which presumably originated from bats, demonstrating that the risk of a new outbreak of bat coronavirus is always latent. Therefore, an in-depth investigation to better comprehend bat CoVs has become an important issue within the international community, a group that aims to attenuate the consequences of future outbreaks. In this review, we present a concise introduction to CoVs found in bats and discuss their distribution in Southeast Asia. We also discuss the unique adaptation features in bats that confer the ability to be a potential coronavirus reservoir. In addition, we review the bat coronavirus-linked diseases that have emerged in the last two decades. Finally, we propose key factors helpful in the prediction of a novel coronavirus outbreak and present the most recent methods used to forecast an evolving outbreak.


Subject(s)
Chiroptera/virology , Coronavirus/classification , SARS-CoV-2 , Animals , Asia, Southeastern , Global Health
18.
Signal Transduct Target Ther ; 6(1): 339, 2021 09 08.
Article in English | MEDLINE | ID: covidwho-1402052

ABSTRACT

The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has placed a global public burden on health authorities. Although the virological characteristics and pathogenesis of COVID-19 has been largely clarified, there is currently no specific therapeutic measure. In severe cases, acute SARS-CoV-2 infection leads to immune disorders and damage to both the adaptive and innate immune responses. Having roles in immune regulation and regeneration, mesenchymal stem cells (MSCs) serving as a therapeutic option may regulate the over-activated inflammatory response and promote recovery of lung damage. Since the outbreak of the COVID-19 pandemic, a series of MSC-therapy clinical trials has been conducted. The findings indicate that MSC treatment not only significantly reduces lung damage, but also improves patient recovery with safety and good immune tolerance. Herein, we summarize the recent progress in MSC therapy for COVID-19 and highlight the challenges in the field.


Subject(s)
COVID-19/therapy , Lung Injury/therapy , Lung/immunology , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/immunology , SARS-CoV-2/immunology , Animals , COVID-19/immunology , COVID-19/pathology , Humans , Lung/pathology , Lung/virology , Lung Injury/immunology , Lung Injury/virology , Mesenchymal Stem Cells/pathology
19.
Cell Res ; 31(10): 1047-1060, 2021 10.
Article in English | MEDLINE | ID: covidwho-1380899

ABSTRACT

The outbreak of SARS-CoV-2 (SARS2) has caused a global COVID-19 pandemic. The spike protein of SARS2 (SARS2-S) recognizes host receptors, including ACE2, to initiate viral entry in a complex biomechanical environment. Here, we reveal that tensile force, generated by bending of the host cell membrane, strengthens spike recognition of ACE2 and accelerates the detachment of spike's S1 subunit from the S2 subunit to rapidly prime the viral fusion machinery. Mechanistically, such mechano-activation is fulfilled by force-induced opening and rotation of spike's receptor-binding domain to prolong the bond lifetime of spike/ACE2 binding, up to 4 times longer than that of SARS-S binding with ACE2 under 10 pN force application, and subsequently by force-accelerated S1/S2 detachment which is up to ~103 times faster than that in the no-force condition. Interestingly, the SARS2-S D614G mutant, a more infectious variant, shows 3-time stronger force-dependent ACE2 binding and 35-time faster force-induced S1/S2 detachment. We also reveal that an anti-S1/S2 non-RBD-blocking antibody that was derived from convalescent COVID-19 patients with potent neutralizing capability can reduce S1/S2 detachment by 3 × 106 times under force. Our study sheds light on the mechano-chemistry of spike activation and on developing a non-RBD-blocking but S1/S2-locking therapeutic strategy to prevent SARS2 invasion.


Subject(s)
COVID-19/diagnosis , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/metabolism , Tensile Strength , Angiotensin-Converting Enzyme 2/chemistry , Angiotensin-Converting Enzyme 2/metabolism , Antibodies, Neutralizing/immunology , Binding Sites , COVID-19/therapy , COVID-19/virology , Humans , Hydrogen-Ion Concentration , Immunization, Passive , Molecular Dynamics Simulation , Protein Binding , Protein Domains/immunology , Protein Subunits/chemistry , Protein Subunits/immunology , Protein Subunits/metabolism , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/immunology , Virus Internalization
20.
Front Immunol ; 12: 700152, 2021.
Article in English | MEDLINE | ID: covidwho-1359189

ABSTRACT

Background: Mucosal-associated invariant T (MAIT) cells are considered to participate of the host immune response against acute severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection; however, single-cell transcriptomic profiling of MAIT cells in patients with COVID-19 remains unexplored. Methods: We performed single-cell RNA sequencing analyses on peripheral MAIT cells from 13 patients with COVID-19 and 5 healthy donors. The transcriptional profiles of MAIT cells, together with assembled T-cell receptor sequences, were analyzed. Flow cytometry analysis was also performed to investigate the properties of MAIT cells. Results: We identified that differentially expressed genes (DEGs) of MAIT cells were involved in myeloid leukocyte activation and lymphocyte activation in patients with COVID-19. In addition, in MAIT cells from severe cases, more DEGs were enriched in adaptive cellular and humoral immune responses compared with those in moderate cases. Further analysis indicated that the increase of cell cytotoxicity (killing), chemotaxis, and apoptosis levels in MAIT cells were consistent with disease severity and displayed the highest levels in patients with severe disease. Interestingly, flow cytometry analysis showed that the frequencies of pyroptotic MAIT cells, but not the frequencies of apoptotic MAIT cells, were increased significantly in patients with COVID-19, suggesting pyroptosis is one of leading causes of MAIT cell deaths during SARS-CoV-2 infection. Importantly, there were more clonal expansions of MAIT cells in severe cases than in moderate cases. Conclusions: The results of the present study suggest that MAIT cells are likely to be involved in the host immune response against SARS-CoV-2 infection. Simultaneously, the transcriptomic data from MAIT cells provides a deeper understanding of the immune pathogenesis of the disease.


Subject(s)
COVID-19/immunology , Mucosal-Associated Invariant T Cells/immunology , SARS-CoV-2/immunology , Transcriptome/genetics , Base Sequence , COVID-19/pathology , Gene Expression Profiling , Gene Expression Regulation/genetics , Gene Expression Regulation/immunology , Humans , Lymphocyte Activation/genetics , Pyroptosis/physiology , Sequence Analysis, RNA , Severity of Illness Index , VDJ Exons/genetics
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