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2.
Animal Model Exp Med ; 5(1): 89-93, 2022 02.
Article in English | MEDLINE | ID: covidwho-1712020

ABSTRACT

BACKGROUND: The Omicron (B.1.1.529) SARS-COV-2 variant has raised serious concerns because of its unprecedented rapid rate of spreading and the fact that there are 36 mutations in the spike protein. Since the vaccine-induced neutralizing antibody targets are the spike protein, this may lead to the possibility of vaccine-induced humoral immunity escape. METHODS: We measured the neutralizing activity in vitro for Omicron and compared this with wild type (WH-09) and Delta variants in human and monkey sera from different types of immunity. The monkey sera samples were collected at 1 and 3 months post three-dose inactivated (PiCoVacc) and recombinant protein (ZF2001) vaccination. Human sera were collected from 1 month post three-dose inactivated vaccination. RESULTS: In inactivated vaccine sera, at 1/3 months post three-dose, geometric mean titers (GMTs) of neutralization antibody (NAb) against the Omicron variant were 4.9/5.2-fold lower than those of the wild type. In recombinant protein vaccine sera, GMTs of NAb against Omicron were 15.7/8.9-fold lower than those of the wild type. In human sera, at 1 month post three-dose inactivated vaccination, GMTs of NAb against Omicron were 3.1-fold lower than those of the wild type. CONCLUSION: This study demonstrated that despite a reduction in neutralization titers, cross-neutralizing activity against Omicron and Delta variants was still observed after three doses of inactivated and recombinant protein vaccination.


Subject(s)
Antibodies, Viral/blood , COVID-19 Vaccines/administration & dosage , COVID-19 , Cross Reactions , SARS-CoV-2 , Animals , Antibodies, Neutralizing/blood , COVID-19/immunology , COVID-19/prevention & control , COVID-19 Vaccines/immunology , Haplorhini , Humans , Neutralization Tests , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/genetics
3.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-323719

ABSTRACT

The SARS-CoV-2 has led to a worldwide health crisis. The ACE2 has been identified as the entry receptor in a species-specific manner. Classic laboratory mice were insusceptible since the virus cannot use murine ACE2 orthologue. Animal models rely on gene modification on the virus or the host. However, these mice were restricted in limited genetic backgrounds and did not support natural infection. Here we showed two wild-type inbred lines (CAST and FEW) from Genetic Diversity mice supported authentic SARS-CoV-2 infection, and developed mild to moderate interstitial pneumonia, along with infiltrating inflammatory cells. Particularly, FEW featured age-dependent damages, while CAST charactered by pulmonary fibrosis. Genome and transcriptome comparative analysis suggested the mutated ACE2 was not responsible for SARS-CoV-2 infection in CAST and FEW, and the differential gene expressions in immune response and immune cell may be risk factors for the infection. In summary, the GD mice, derived from the multi-parental panel, provided promising murine models for exploring sophisticated pathogenesis in SARS-CoV-2.

4.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-311706

ABSTRACT

The SARS-CoV-2 pandemic poses an unprecedented public health crisis. Accumulating evidences suggest that SARS-CoV-2 infection causes dysregulation of immune system. However, the unique signature of early immune responses remains elusive. We characterized the transcriptome of rhesus macaques and mice infected with SARS-CoV-2. Alarmin S100A8 was robustly induced by SARS-CoV-2 in animal models as well as in COVID-19 patients. Paquinimod, a specific inhibitor of S100A8/A9, could reduce inflammatory response and rescue the pneumonia with substantial reduction of viral titers in SASR-CoV-2 infected animals. Remarkably, Paquinimod treatment resulted in 100% survival of mice in a lethal model of mouse coronavirus (MHV) infection. A novel group of neutrophils that contributed to the uncontrolled inflammation and onset of COVID-19 were dramatically induced by coronavirus infections. Paquinimod treatment could reduce these neutrophils and regain antiviral responses, unveiling key roles of S100A8/A9 and noncanonical neutrophils in the pathogenesis of COVID-19, highlighting new opportunities for therapeutic intervention.Funding: This work was supported by the National Natural Science Foundation of China (31570891;31872736), the National Key Research and Development Program of China (2016YFA0500302;2020YFA0707800), the National Key Research and Development Program (2020YFA0707500) and the Strategic Priority Research Program (XDB29010000). Xiangxi Wang was supported by Ten Thousand Talent Program and the NSFS Innovative Research Group (81921005). We thank National Mega projects of China for Major Infectious Diseases (2017ZX10304402), CAMS initiative for Innovative Medicine of China (2016-12M-2-006) and The National Natural Science Foundation of China (82041008) for the support on the animal model study. Conflict of Interest: The authors have no conflicts of interest to declare.Ethical Approval: All experiments with live SARS-CoV-2 viruses were carried out in the enhanced biosafety level 3 (P3+) facilities in the Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) approved by the National Health Commission of the People’s Republic of China. All animals care and use were in accordance with the Guide for the Care and Use of Laboratory Animals of the Chinese Association for Laboratory Animal Science. All procedures of animal handling were approved by the Animal Care Committee of Peking University Health Science Center.

5.
Vet Pathol ; : 3009858211071016, 2022 Jan 29.
Article in English | MEDLINE | ID: covidwho-1662392

ABSTRACT

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes severe viral pneumonia and is associated with a high fatality rate. A substantial proportion of patients infected by SARS-CoV-2 suffer from mild hyposmia to complete loss of olfactory function, resulting in anosmia. However, the pathogenesis of the olfactory dysfunction and comparative pathology of upper respiratory infections with SARS-CoV-2 are unknown. We describe the histopathological, immunohistochemical, and in situ hybridization findings from rodent models of SARS-CoV-2 infection. The main histopathological findings in the olfactory epithelia of K8-hACE2 Tg mice, hACE2 Tg mice, and hamsters were varying degrees of inflammatory lesions, including disordered arrangement, necrosis, exfoliation, and macrophage infiltration of the olfactory epithelia, and inflammatory exudation. On the basis of these observations, the nasal epithelia of these rodent models appeared to develop moderate, mild, and severe rhinitis, respectively. Correspondingly, SARS-CoV-2 viral RNA and antigen were mainly identified in the olfactory epithelia and lamina propria. Moreover, viral RNA was abundant in the cerebrum of K18-hACE2 Tg mice, including the olfactory bulb. The K8-hACE2 Tg mouse, hACE2 Tg mouse, and hamster models could be used to investigate the pathology of SARS-CoV-2 infection in the upper respiratory tract and central nervous system. These models could help to provide a better understanding of the pathogenic process of this virus and to develop effective medications and prophylactic treatments.

6.
Signal Transduct Target Ther ; 7(1): 29, 2022 01 28.
Article in English | MEDLINE | ID: covidwho-1655546

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is transmitted on mink farms between minks and humans in many countries. However, the systemic pathological features of SARS-CoV-2-infected minks are mostly unknown. Here, we demonstrated that minks were largely permissive to SARS-CoV-2, characterized by severe and diffuse alveolar damage, and lasted at least 14 days post inoculation (dpi). We first reported that infected minks displayed multiple organ-system lesions accompanied by an increased inflammatory response and widespread viral distribution in the cardiovascular, hepatobiliary, urinary, endocrine, digestive, and immune systems. The viral protein partially co-localized with activated Mac-2+ macrophages throughout the body. Moreover, we first found that the alterations in lipids and metabolites were correlated with the histological lesions in infected minks, especially at 6 dpi, and were similar to that of patients with severe and fatal COVID-19. Particularly, altered metabolic pathways, abnormal digestion, and absorption of vitamins, lipids, cholesterol, steroids, amino acids, and proteins, consistent with hepatic dysfunction, highlight metabolic and immune dysregulation. Enriched kynurenine in infected minks contributed to significant activation of the kynurenine pathway and was related to macrophage activation. Melatonin, which has significant anti-inflammatory and immunomodulating effects, was significantly downregulated at 6 dpi and displayed potential as a targeted medicine. Our data first illustrate systematic analyses of infected minks to recapitulate those observations in severe and fetal COVID-19 patients, delineating a useful animal model to mimic SARS-CoV-2-induced systematic and severe pathophysiological features and provide a reliable tool for the development of effective and targeted treatment strategies, vaccine research, and potential biomarkers.


Subject(s)
COVID-19/metabolism , Lung/metabolism , Macrophages, Alveolar/metabolism , Metabolome , Mink/virology , SARS-CoV-2/metabolism , Amino Acids/metabolism , Animals , Antiviral Agents/pharmacology , COVID-19/drug therapy , COVID-19/genetics , COVID-19/pathology , Disease Models, Animal , Female , Humans , Lung/pathology , Lung/virology , Macrophages, Alveolar/pathology , Macrophages, Alveolar/virology , Melatonin/metabolism , Metabolic Networks and Pathways/genetics , Molecular Targeted Therapy/methods , SARS-CoV-2/drug effects , SARS-CoV-2/genetics , SARS-CoV-2/pathogenicity , Sterols/metabolism , Virulence , Virus Replication/genetics
7.
Hum Vaccin Immunother ; 18(1): 2016201, 2022 Dec 31.
Article in English | MEDLINE | ID: covidwho-1642249

ABSTRACT

Genetic optimization of Nucleic Acid immunogens is important for potentially improving their immune potency. A COVID-19 DNA vaccine is in phase III clinical trial which is based on a promising highly developable technology platform. Here, we show optimization in mice generating a pGX-9501 DNA vaccine encoding full-length spike protein, which results in induction of potent humoral and cellular immune responses, including neutralizing antibodies, that block hACE2-RBD binding of live CoV2 virus in vitro. Optimization resulted in improved induction of cellular immunity by pGX-9501 as demonstrated by increased IFN-γ expression in both CD8+ and CD4 + T cells and this was associated with more robust antiviral CTL responses compared to unoptimized constructs. Vaccination with pGX-9501 induced subsequent protection against virus challenge in a rigorous hACE2 transgenic mouse model. Overall, pGX-9501 is a promising optimized COVID-19 DNA vaccine candidate inducing humoral and cellular immunity contributing to the vaccine's protective effects.


Subject(s)
COVID-19 , Spike Glycoprotein, Coronavirus , Animals , Antibodies, Neutralizing , Antibodies, Viral , Base Sequence , COVID-19/prevention & control , Mice , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics
8.
J Cardiovasc Transl Res ; 15(1): 38-48, 2022 02.
Article in English | MEDLINE | ID: covidwho-1594479

ABSTRACT

Angiotensin-converting enzyme 2 (ACE2) is required for the cellular entry of the severe acute respiratory syndrome coronavirus 2. ACE2, via the Ang-(1-7)-Mas-R axis, is part of the antihypertensive and cardioprotective effects of the renin-angiotensin system. We studied hospitalized COVID-19 patients with hypertension and hypertensive human(h) ACE2 transgenic mice to determine the outcome of COVID-19 with or without AT1 receptor (AT1R) blocker treatment. The severity of the illness and the levels of serum cardiac biomarkers (CK, CK-BM, cTnI), as well as the inflammation markers (IL-1, IL-6, CRP), were lesser in hypertensive COVID-19 patients treated with AT1R blockers than those treated with other antihypertensive drugs. Hypertensive hACE2 transgenic mice, pretreated with AT1R blocker, had increased ACE2 expression and SARS-CoV-2 in the kidney and heart, 1 day post-infection. We conclude that those hypertensive patients treated with AT1R blocker may be at higher risk for SARS-CoV-2 infection. However, AT1R blockers had no effect on the severity of the illness but instead may have protected COVID-19 patients from heart injury, via the ACE2-angiotensin1-7-Mas receptor axis.


Subject(s)
COVID-19 , Hypertension , Animals , Humans , Hypertension/complications , Hypertension/drug therapy , Inpatients , Mice , Mice, Transgenic , Renin-Angiotensin System , SARS-CoV-2 , Virulence
10.
Mol Biomed ; 2(1): 29, 2021.
Article in English | MEDLINE | ID: covidwho-1515465

ABSTRACT

In the face of the emerging variants of SARS-CoV-2, there is an urgent need to develop a vaccine that can induce fast, effective, long-lasting and broad protective immunity against SARS-CoV-2. Here, we developed a trimeric SARS-CoV-2 S protein vaccine candidate adjuvanted by PIKA, which can induce robust cellular and humoral immune responses. The results showed a high level of neutralizing antibodies induced by the vaccine was maintained for at least 400 days. In the study of non-human primates, PIKA adjuvanted S-trimer induced high SARS-CoV-2 neutralization titers and protected from virus replication in the lung following SARS-CoV-2 challenge. In addition, the long-term neutralizing antibody response induced by S-trimer vaccine adjuvanted by PIKA could neutralize multiple SARS-CoV-2 variants and there is no obvious different among the SARS- CoV-2 variants of interest or concern, including B.1.351, B.1.1.7, P.1, B.1.617.1 and B.1.617.2 variants. These data support the utility of S-trimer protein adjuvanted by PIKA as a potential vaccine candidate against SARS-CoV-2 infection. Supplementary Information: The online version contains supplementary material available at 10.1186/s43556-021-00054-z.

11.
Vaccine ; 39(48): 7001-7011, 2021 11 26.
Article in English | MEDLINE | ID: covidwho-1488001

ABSTRACT

COVID-19 pandemic has severely impacted the public health and social economy worldwide. A safe, effective, and affordable vaccine against SARS-CoV-2 infections/diseases is urgently needed. We have been developing a recombinant vaccine based on a prefusion-stabilized spike trimer of SARS-CoV-2 and formulated with aluminium hydroxide and CpG 7909. The spike protein was expressed in Chinese hamster ovary (CHO) cells, purified, and prepared as a stable formulation with the dual adjuvant. Immunogenicity studies showed that candidate vaccines elicited robust neutralizing antibody responses and substantial CD4+ T cell responses in both mice and non-human primates. And vaccine-induced neutralizing antibodies persisted at high level for at least 6 months. Challenge studies demonstrated that candidate vaccine reduced the viral loads and inflammation in the lungs of SARS-CoV-2 infected golden Syrian hamsters significantly. In addition, the vaccine-induced antibodies showed cross-neutralization activity against B.1.1.7 and B.1.351 variants. These data suggest candidate vaccine is efficacious in preventing SARS-CoV-2 infections and associated pneumonia, thereby justifying ongoing phase I/II clinical studies in China (NCT04982068 and NCT04990544).


Subject(s)
COVID-19 Vaccines , COVID-19 , Alum Compounds , Aluminum Hydroxide , Animals , Antibodies, Neutralizing , Antibodies, Viral , CHO Cells , Cricetinae , Cricetulus , Humans , Mice , Pandemics , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/genetics
13.
Acta Pharm Sin B ; 11(9): 2850-2858, 2021 Sep.
Article in English | MEDLINE | ID: covidwho-1415197

ABSTRACT

COVID-19 pandemic caused by SARS-CoV-2 infection severely threatens global health and economic development. No effective antiviral drug is currently available to treat COVID-19 and any other human coronavirus infections. We report herein that a macrolide antibiotic, carrimycin, potently inhibited the cytopathic effects (CPE) and reduced the levels of viral protein and RNA in multiple cell types infected by human coronavirus 229E, OC43, and SARS-CoV-2. Time-of-addition and pseudotype virus infection studies indicated that carrimycin inhibited one or multiple post-entry replication events of human coronavirus infection. In support of this notion, metabolic labelling studies showed that carrimycin significantly inhibited the synthesis of viral RNA. Our studies thus strongly suggest that carrimycin is an antiviral agent against a broad-spectrum of human coronaviruses and its therapeutic efficacy to COVID-19 is currently under clinical investigation.

14.
Signal Transduct Target Ther ; 6(1): 337, 2021 09 06.
Article in English | MEDLINE | ID: covidwho-1402050

ABSTRACT

SARS-CoV-2 has been reported to show a capacity for invading the brains of humans and model animals. However, it remains unclear whether and how SARS-CoV-2 crosses the blood-brain barrier (BBB). Herein, SARS-CoV-2 RNA was occasionally detected in the vascular wall and perivascular space, as well as in brain microvascular endothelial cells (BMECs) in the infected K18-hACE2 transgenic mice. Moreover, the permeability of the infected vessel was increased. Furthermore, disintegrity of BBB was discovered in the infected hamsters by administration of Evans blue. Interestingly, the expression of claudin5, ZO-1, occludin and the ultrastructure of tight junctions (TJs) showed unchanged, whereas, the basement membrane was disrupted in the infected animals. Using an in vitro BBB model that comprises primary BMECs with astrocytes, SARS-CoV-2 was found to infect and cross through the BMECs. Consistent with in vivo experiments, the expression of MMP9 was increased and collagen IV was decreased while the markers for TJs were not altered in the SARS-CoV-2-infected BMECs. Besides, inflammatory responses including vasculitis, glial activation, and upregulated inflammatory factors occurred after SARS-CoV-2 infection. Overall, our results provide evidence supporting that SARS-CoV-2 can cross the BBB in a transcellular pathway accompanied with basement membrane disrupted without obvious alteration of TJs.


Subject(s)
Basement Membrane/metabolism , Blood-Brain Barrier/metabolism , COVID-19/metabolism , SARS-CoV-2/metabolism , Tight Junctions/metabolism , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/metabolism , Animals , Basement Membrane/pathology , Basement Membrane/virology , Blood-Brain Barrier/pathology , Blood-Brain Barrier/virology , COVID-19/genetics , COVID-19/pathology , Chlorocebus aethiops , Disease Models, Animal , Humans , Matrix Metalloproteinase 9/genetics , Matrix Metalloproteinase 9/metabolism , Mice , Mice, Transgenic , SARS-CoV-2/genetics , Tight Junctions/genetics , Tight Junctions/pathology , Tight Junctions/virology , Vero Cells
16.
Signal Transduct Target Ther ; 6(1): 200, 2021 05 20.
Article in English | MEDLINE | ID: covidwho-1237988

ABSTRACT

Influenza A virus may circulate simultaneously with the SARS-CoV-2 virus, leading to more serious respiratory diseases during this winter. However, the influence of these viruses on disease outcome when both influenza A and SARS-CoV-2 are present in the host remains unclear. Using a mammalian model, sequential infection was performed in ferrets and in K18-hACE2 mice, with SARS-CoV-2 infection following H1N1. We found that co-infection with H1N1 and SARS-CoV-2 extended the duration of clinical manifestation of COVID-19, and enhanced pulmonary damage, but reduced viral shedding of throat swabs and viral loads in the lungs of ferrets. Moreover, mortality was increased in sequentially infected mice compared with single-infection mice. Compared with single-vaccine inoculation, co-inoculation of PiCoVacc (a SARS-CoV-2 vaccine) and the flu vaccine showed no significant differences in neutralizing antibody titers or virus-specific immune responses. Combined immunization effectively protected K18-hACE2 mice against both H1N1 and SARS-CoV-2 infection. Our findings indicated the development of systematic models of co-infection of H1N1 and SARS-CoV-2, which together notably enhanced pneumonia in ferrets and mice, as well as demonstrated that simultaneous vaccination against H1N1 and SARS-CoV-2 may be an effective prevention strategy for the coming winter.


Subject(s)
COVID-19 , Coinfection , Influenza A Virus, H1N1 Subtype/immunology , Orthomyxoviridae Infections , SARS-CoV-2/immunology , Animals , COVID-19/immunology , COVID-19/pathology , COVID-19/virology , Coinfection/immunology , Coinfection/pathology , Coinfection/virology , Disease Models, Animal , Ferrets , Humans , Male , Mice , Mice, Transgenic , Orthomyxoviridae Infections/immunology , Orthomyxoviridae Infections/pathology , Orthomyxoviridae Infections/virology
17.
Cell Discov ; 7(1): 24, 2021 Apr 13.
Article in English | MEDLINE | ID: covidwho-1182824

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) invades the alveoli, where abundant alveolar macrophages (AMs) reside. How AMs respond to SARS-CoV-2 invasion remains elusive. Here, we show that classically activated M1 AMs facilitate viral spread; however, alternatively activated M2 AMs limit the spread. M1 AMs utilize cellular softness to efficiently take up SARS-CoV-2. Subsequently, the invaded viruses take over the endo-lysosomal system to escape. M1 AMs have a lower endosomal pH, favoring membrane fusion and allowing the entry of viral RNA from the endosomes into the cytoplasm, where the virus achieves replication and is packaged to be released. In contrast, M2 AMs have a higher endosomal pH but a lower lysosomal pH, thus delivering the virus to lysosomes for degradation. In hACE2 transgenic mouse model, M1 AMs are found to facilitate SARS-CoV-2 infection of the lungs. These findings provide insights into the complex roles of AMs during SARS-CoV-2 infection, along with potential therapeutic targets.

19.
Animal Model Exp Med ; 4(1): 2-15, 2021 03.
Article in English | MEDLINE | ID: covidwho-1122088

ABSTRACT

Background: Cardiovascular diseases (CVDs) and diabetes mellitus (DM) are top two chronic comorbidities that increase the severity and mortality of COVID-19. However, how SARS-CoV-2 alters the progression of chronic diseases remain unclear. Methods: We used adenovirus to deliver h-ACE2 to lung to enable SARS-CoV-2 infection in mice. SARS-CoV-2's impacts on pathogenesis of chronic diseases were studied through histopathological, virologic and molecular biology analysis. Results: Pre-existing CVDs resulted in viral invasion, ROS elevation and activation of apoptosis pathways contribute myocardial injury during SARS-CoV-2 infection. Viral infection increased fasting blood glucose and reduced insulin response in DM model. Bone mineral density decreased shortly after infection, which associated with impaired PI3K/AKT/mTOR signaling. Conclusion: We established mouse models mimicked the complex pathological symptoms of COVID-19 patients with chronic diseases. Pre-existing diseases could impair the inflammatory responses to SARS-CoV-2 infection, which further aggravated the pre-existing diseases. This work provided valuable information to better understand the interplay between the primary diseases and SARS-CoV-2 infection.


Subject(s)
COVID-19/complications , COVID-19/physiopathology , Cardiovascular Diseases/complications , Cardiovascular Diseases/physiopathology , Diabetes Complications/physiopathology , Animals , Comorbidity , Diabetes Mellitus , Disease Models, Animal , Male , Mice , SARS-CoV-2
20.
J Infect Dis ; 223(8): 1313-1321, 2021 04 23.
Article in English | MEDLINE | ID: covidwho-1091239

ABSTRACT

Domestic cats, an important companion animal, can be infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). This has aroused concern regarding the ability of domestic cats to spread the virus that causes coronavirus disease 2019. We systematically demonstrated the pathogenesis and transmissibility of SARS-CoV-2 in cats. Serial passaging of the virus between cats dramatically attenuated the viral transmissibility, likely owing to variations of the amino acids in the receptor-binding domain sites of angiotensin-converting enzyme 2 between humans and cats. These findings provide insight into the transmissibility of SARS-CoV-2 in cats and information for protecting the health of humans and cats.


Subject(s)
COVID-19/transmission , COVID-19/veterinary , SARS-CoV-2/pathogenicity , Amino Acids/metabolism , Angiotensin-Converting Enzyme 2/metabolism , Animals , COVID-19/metabolism , Cats , Cell Line , Chlorocebus aethiops , Female , Humans , Male , Vero Cells
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