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1.
Chin Med J (Engl) ; 133(9): 1015-1024, 2020 May 05.
Article in English | MEDLINE | ID: covidwho-1722617

ABSTRACT

BACKGROUND: Human infections with zoonotic coronaviruses (CoVs), including severe acute respiratory syndrome (SARS)-CoV and Middle East respiratory syndrome (MERS)-CoV, have raised great public health concern globally. Here, we report a novel bat-origin CoV causing severe and fatal pneumonia in humans. METHODS: We collected clinical data and bronchoalveolar lavage (BAL) specimens from five patients with severe pneumonia from Wuhan Jinyintan Hospital, Hubei province, China. Nucleic acids of the BAL were extracted and subjected to next-generation sequencing. Virus isolation was carried out, and maximum-likelihood phylogenetic trees were constructed. RESULTS: Five patients hospitalized from December 18 to December 29, 2019 presented with fever, cough, and dyspnea accompanied by complications of acute respiratory distress syndrome. Chest radiography revealed diffuse opacities and consolidation. One of these patients died. Sequence results revealed the presence of a previously unknown ß-CoV strain in all five patients, with 99.8% to 99.9% nucleotide identities among the isolates. These isolates showed 79.0% nucleotide identity with the sequence of SARS-CoV (GenBank NC_004718) and 51.8% identity with the sequence of MERS-CoV (GenBank NC_019843). The virus is phylogenetically closest to a bat SARS-like CoV (SL-ZC45, GenBank MG772933) with 87.6% to 87.7% nucleotide identity, but is in a separate clade. Moreover, these viruses have a single intact open reading frame gene 8, as a further indicator of bat-origin CoVs. However, the amino acid sequence of the tentative receptor-binding domain resembles that of SARS-CoV, indicating that these viruses might use the same receptor. CONCLUSION: A novel bat-borne CoV was identified that is associated with severe and fatal respiratory disease in humans.


Subject(s)
Betacoronavirus , Coronavirus Infections/virology , Pneumonia, Viral/virology , Adult , Aged , Betacoronavirus/genetics , Betacoronavirus/isolation & purification , COVID-19 , Coronavirus Infections/diagnostic imaging , Coronavirus Infections/therapy , Female , Humans , Male , Middle Aged , Pandemics , Pneumonia, Viral/diagnostic imaging , Pneumonia, Viral/therapy , SARS-CoV-2 , Tomography, X-Ray , Treatment Outcome
2.
Nat Prod Res ; : 1-4, 2022 Feb 24.
Article in English | MEDLINE | ID: covidwho-1699339

ABSTRACT

Geraniin is a polyphenolic compound first isolated from Geranium thunbergii. The major protease (Mpro), namely 3 C-like protease (3CLpro), of coronaviruses is considered an attractive drug target as it is essential for the processing and maturation of viral polyproteins. Thus, our primary goal is to explore the efficiency of geraniin on 3CLpro of SARS-CoV-2 using the computational biology strategy. In this work, we studied the anti-coronavirus effect of geraniin in vitro and its potential inhibitory mode against the 3CLpro of SARS-CoV-2. We found that geraniin inhibited HCoV-OC43 coronavirus-infected cells during the attachment and penetration phases. Molecular docking and dynamics simulations exhibited that geraniin had a strong binding affinity and high stable binding to 3CLpro of SARS-CoV-2. Geraniin showed a strong inhibitory activity on coronavirus and may be a potential inhibitor of SARS-CoV-2 3CLpro.

3.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-324715

ABSTRACT

Objectives: We aimed to develop and validate the automatic quantification of COVID-19 pneumonia on CT images. Methods: This retrospective study included 176 chest CT scans of 131 COVID-19 patients from 13 Korean and Chinese institutions. Two experienced radiologists semi-automatically drew pneumonia, preparing 49,830 positive and negative CT slices to develop the 2D U-Net for segmenting pneumonia. The 2D U-Net was distributed as downloadable software. External validation for quantifications’ accuracy was performed using Japanese, Italian, Radiopaedia, Chinese datasets. Primary measures for the accuracy of the network were correlation coefficients for extent (%) and weight (g) of pneumonia. Logistic regression analyses were performed to evaluate the clinical implication of the extent and weight regarding the presence of symptoms in the Japanese dataset and the occurrence of composite outcome in the Spanish dataset. Results: In the internal validation dataset, the intraclass correlation coefficients between the 2D U-Net and reference values for the extent and weight were 0.990 and 0.993, respectively. In the Japanese dataset, the Pearson correlation coefficients between the U-Net outcomes and visual CT severity scores were 0.908 and 0.899, respectively. In the other external validation datasets, the intraclass correlation coefficients between the U-Net and reference values were between 0.951-0.970 (extent) and between 0.970-0.995 (weight), respectively. In multivariate logistic regression analyses, the extent and weight of pneumonia were independently associated with symptoms (OR, 4.142 and 4.434;p=.013 and .009, respectively), and poor prognosis (OR, 7.446 and 4.677;p=.004 and .029, respectively). Conclusions: CT extent and weight of COVID-19 pneumonia were automatically quantifiable and independently associated with symptoms and prognosis.

4.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-324186

ABSTRACT

Severe acute respiratory syndrome coronavirus (SARS-CoV) and SARS-CoV-2 have been thought to originate from bat, but whether the cross-species transmission occurred directly from bat to human or through an intermediate host remains elusive. In this study, we performed CoV screening of 102 samples collected from animal-selling stalls of Wuhan Huanan Market (WHM) and pharyngeal and anal swabs from13,064 bats collected at 703 locations across China, covering almost all known southern hotspots for sarbecovirus, between 2016 and 2021. This is the first systematic survey of bat CoV in China during the outbreak of Corona Virus Disease 2019. We found four non-sarbeco CoVs in samples of WHM, and 142 SARS-CoV related CoVs (SARSr-CoV) and 4 recombinant CoVs in bats, of which YN2020B-G share the highest sequence identity with SARS-CoV among all known bat CoVs, suggesting endemic SARSr-CoVs in bats in China. However, we did not find any SARS-CoV-2 related CoVs (SC2r-CoV) in any samples, including specimens collected from the only two domestic places where RaTG13 and RmYN02 were previously reported (the Tongguan caves and the karst caves around the Xishuangbanna Tropical Botanical Garden), indicating that SC2r-CoVs might not actively circulate among bats in China. Phylogenetic analysis showed that there are three different lineages of sarbecoviruses, L1 (SARSr-CoV), L2 (SC2r-CoV), and L-R (a novel CoV lineage from L1 and L2 recombination), in China. Of note, L-R CoVs are only found in R. pusillus. Further macroscopical analysis of the genetic diversity, host specificity for colonization and accidental infection, and geographical characteristics of available CoVs in database revealed the presence of a general geographical distribution pattern for bat sarbecoviruses, with the highest genetic diversity and sequence homology to SARS-CoV or SARS-CoV-2 along the southwest border of China, the least in the northwest of China. Considering the receptor binding motifs for spike gene of sarbecoviruses in Indochina Peninsula show the greatest diversity, our data provide the rationale that extensive surveys in further south and southwest to or of China might be needed for finding closer ancestors of SARS-CoV and SARS-CoV-2.

5.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-318459

ABSTRACT

Since beginning of this century, there have already been three zoonotic outbreaks caused by beta coronaviruses (CoV), SARS-CoV in 2002-2003, MERS-CoV in 2012, and the newly identified 2019-nCoV in late 2019, Wuhan, China. As to Feb 10 th , 2020, there are over 40,000 confirmed cases and over 900 deaths. However, little is known about the biology of this newly emerged virus. Here we developed a lentiviral based pseudovirus system for S protein of 2019-nCoV to study virus entry in BSL2 settings. First, we confirmed that human angiotensin converting enzyme 2 (hACE2) is the main entry receptor for 2019-nCoV. Second, we found that 2019-nCoV S protein mediated entry on 293/hACE2 cells was mainly through endocytosis, and PIKfyve, TPC2, and cathepsin L are critical for virus entry. Third, 2019-nCoV S protein is less stable than SARS-CoV, and it could trigger protease-independent and receptor dependent cell-cell fusion, which might help virus rapidly spread from cell to cell. Finally and more importantly, polyclonal anti-SARS S1 antibodies T62 effectively inhibited entry of SARS-CoV S pseudovirions, but almost had no effect on entry of 2019-nCoV S pseudovirions. Further studies using sera from one recovered SARS-CoV patient and five 2019-nCoV patients showed that there was only limited cross-neutralization activities between SARS-CoV and 2019-nCoV sera, suggesting that recovery from one infection might not protect against the other. Our results present potential targets for development of drugs and vaccines for 2019-nCoV.

6.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-311704

ABSTRACT

Background: Seasonal human coronaviruses (HCoVs) including HCoV-229E, -OC43, -NL63 and -HKU1 are widely spreading in global human populations. However, the relevance of humoral response against seasonal HCoVs to COVID-19 pathogenesis is elusive.Methods: We profiled the temporal changes of IgG antibodies against spike (S;S-IgG) proteins of SARS-CoV-2 and seasonal HCoVs in 838 plasma samples collected from 344 COVID-19 patients. We tested the antigenic cross-reactivity of S protein between SARS-CoV-2 and seasonal HCoVs and evaluated the correlations between HCoV-OC43 S-IgG antibody and disease severity in COVID-19 patients.Findings: SARS-CoV-2 S-IgG titers mounted until days 22–28, whereas HCoV-OC43 antibody titers increased until days 15–21 and then plateaued until day 46. However, IgG antibody titers against HCoV-NL63, -229E, and -HKU1 showed no significant increasing. A two-way cross-reactivity was identified between SARS-CoV-2 and HCoV-OC43. Neutralizing antibodies against SARS-CoV-2 were not detected in healthy controls who were positive for HCoV-OC43 S-IgG. HCoV-OC43 S-IgG titers were significantly higher in patients with severe disease than those in mild/moderate patients at days 1–21 post symptom onset (PSO). Higher levels of HCoV-OC43 S-IgG were also observed in patients requiring mechanical ventilation and the elderly. At days 1–10 PSO, HCoV-OC43 S-IgG titers correlated to disease severity in all age groups, and to fatality in over 60-year group.Interpretation: Our data indicate that there exist a humoral cross-reactive response between HCoV-OC43 and SARS-CoV-2. The cross-reactive HCoV-OC43 S-IgG antibody is not protective against SARS-CoV-2, but may be a risk factor for the severity and adverse outcome of COVID-19.Funding Statement: This study was funded in part by the National Major Science & Technology Project for Control and Prevention of Major Infectious Diseases in China (2017ZX10204401, 2018ZX10734404), Chinese Academy of Medical Sciences (CAMS) Innovation Fund for Medical Sciences (2016-I2M-1–014, 2018-I2M-1-003, 2020-I2M-1-001, 2020-I2M-CoV19-005), Natural Science Foundation of China (82041011/H0104), and National Key R&D Program of China (2020YFA0707600). Declaration of Interests: The authors declare no competing interests.Ethics Approval Statement: This study was approved by the Ethical Review Board of Wuhan Jinyintan Hospital, Infectious Disease Hospital of Heilongjiang Province (Harbin), and Institute of Pathogen Biology, Chinese Academy of Medical Sciences. Written informed consent was obtained from each healthy volunteer and COVID-19 patients in cohort 4. Written informed consents from the remaining patients were waived in light of the emerging infectious disease of high public health relevance.

7.
Int J Gen Med ; 14: 7337-7348, 2021.
Article in English | MEDLINE | ID: covidwho-1504988

ABSTRACT

OBJECTIVE: Coronavirus disease 2019 (COVID-19) was associated with a higher risk of arrhythmia in infected patients. However, there are no reports about the effect of the ongoing pandemic on arrhythmias in the non-infected population. We measured the arrhythmia burden in a non-infected population with cardiac implantable devices. METHODS: The arrhythmia burden during the COVID-19 pandemic was compared to a 6-month interval in the pre-COVID-19 period. The COVID-19 pandemic was divided into high-risk (17 January 2020 to 16 March 2020) and low-risk periods (17 March 2020 to 17 July 2020) according to whether there were locally infected patients. Arrhythmia burdens were compared among the pre-COVID-19, high-risk, and low-risk periods. RESULTS: A total of 219 patients with 1859 episodes were included. We observed a larger proportion of patients with atrial fibrillation (AF) during the COVID-19 pandemic (38.36% vs 26.03%, p = 0.006). There was not significantly more ventricular arrhythmia during the COVID period than the pre-COVID-19 period (p > 0.05). During the high-risk period, daily frequency of non-sustained ventricular tachycardia (NSVT) (0.0172, 0.0475 vs 0.0109, 0.0164, p < 0.05), atrial tachycardia (AT) (0.0345, 0.0518 vs 0.0164, 0.0219 p < 0.05) and AF (0.0345, 0.0432 vs 0.0164, 0.0186, p < 0.05) and daily duration of NSVT (0.1982, 0.2845 vs 0.0538, 0.1640 p < 0.05) were higher and longer than those in the pre-COVID-19 period. Regression modeling showed that the impact of COVID-19 pandemic lead to an increased onset of AF (odds ratio 2.465; p < 0.01). Patients with paroxysmal AF who had undergone a previous radiofrequency ablation had a lower burden of AF (incidence 21.43% vs 55.00%, P = 0.049, daily frequency 0.0000, 0.0027 vs 0.0000, 241.7978, P = 0.020) during the pandemic. CONCLUSION: The COVID-19 pandemic contributed to a higher burden of arrhythmias in non-infected patients. Patients would experience a lower burden of AF following radiofrequency ablation treatment, and this effect persisted during the pandemic.

11.
Chinese Journal of Nosocomiology ; 30(24):3692-3696, 2020.
Article in English | GIM | ID: covidwho-1318607

ABSTRACT

OBJECTIVE: To introduce the measures to prevent and control the infection in a hospital in Qiqihaer. By formulating full-responsibility system and supervisor system of the hospital infection monitoring and management, it is not only optimize the management of the position of medical staff and reduce the exposure risk of all people in the hospital, but also provide references of prevention and control of Covid-19 for other medical institutions aiming to ensure the normalization and long-term effectiveness. METHODS: The epidemic prevention and control relevant systems, processes, measures, emergency plans for each department were formulated by combining the normative documents of the higher-level departments and the actual situation of our own institution. The hospital-responsibility system was established and improved based on the principle of different areas, contents, time periods and links, implement responsibility to everyone in each part, to form an effective supervision mechanism. RESULTS: All departments performed their duties and personnel responsibilities strictly, and established a reasonably and orderly work flows in the hospital during the COVID-19 epidemic. Besides, the ability of preventing and controlling the epidemic was improved continuously, which ensured normal medical activities that can be completed efficiently and orderly in the normalization of the epidemic. CONCLUSION: The scientific and effective hospital infection monitoring and management can not only enable the various departments to carry out daily work in an orderly manner, but also respond to the emergency situation of the epidemic. The most important thing is to implement the control work under the normalization of the epidemic.

12.
Clin Infect Dis ; 71(15): 778-785, 2020 07 28.
Article in English | MEDLINE | ID: covidwho-1217823

ABSTRACT

BACKGROUND: The emergence of coronavirus disease 2019 (COVID-19) is a major healthcare threat. The current method of detection involves a quantitative polymerase chain reaction (qPCR)-based technique, which identifies the viral nucleic acids when present in sufficient quantity. False-negative results can be achieved and failure to quarantine the infected patient would be a major setback in containing the viral transmission. We aim to describe the time kinetics of various antibodies produced against the 2019 novel coronavirus (SARS-CoV-2) and evaluate the potential of antibody testing to diagnose COVID-19. METHODS: The host humoral response against SARS-CoV-2, including IgA, IgM, and IgG response, was examined by using an ELISA-based assay on the recombinant viral nucleocapsid protein. 208 plasma samples were collected from 82 confirmed and 58 probable cases (qPCR negative but with typical manifestation). The diagnostic value of IgM was evaluated in this cohort. RESULTS: The median duration of IgM and IgA antibody detection was 5 (IQR, 3-6) days, while IgG was detected 14 (IQR, 10-18) days after symptom onset, with a positive rate of 85.4%, 92.7%, and 77.9%, respectively. In confirmed and probable cases, the positive rates of IgM antibodies were 75.6% and 93.1%, respectively. The detection efficiency by IgM ELISA is higher than that of qPCR after 5.5 days of symptom onset. The positive detection rate is significantly increased (98.6%) when combining IgM ELISA assay with PCR for each patient compared with a single qPCR test (51.9%). CONCLUSIONS: The humoral response to SARS-CoV-2 can aid in the diagnosis of COVID-19, including subclinical cases.


Subject(s)
Betacoronavirus/immunology , Coronavirus Infections/diagnosis , Coronavirus Infections/immunology , Immunity, Humoral/immunology , Pneumonia, Viral/diagnosis , Pneumonia, Viral/immunology , Adult , Amino Acid Sequence , Antibodies, Viral/immunology , COVID-19 , Child , Child, Preschool , Coronavirus Infections/virology , Enzyme-Linked Immunosorbent Assay/methods , Female , Humans , Male , Middle Aged , Pandemics , Pneumonia, Viral/virology , Polymerase Chain Reaction/methods , SARS-CoV-2
13.
Emerg Microbes Infect ; 10(1): 664-676, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1139855

ABSTRACT

Seasonal human coronaviruses (HCoVs) including HCoV-229E, -OC43, -NL63, and -HKU1 widely spread in global human populations. However, the relevance of humoral response against seasonal HCoVs to COVID-19 pathogenesis is elusive. In this study, we profiled the temporal changes of IgG antibody against spike proteins (S-IgG) of SARS-CoV-2 and seasonal HCoVs in 838 plasma samples collected from 344 COVID-19 patients. We tested the antigenic cross-reactivities of S protein between SARS-CoV-2 and seasonal HCoVs and evaluated the correlations between the levels of HCoV-OC43 S-IgG and the disease severity in COVID-19 patients. We found that SARS-CoV-2 S-IgG titres mounted until days 22-28, whereas HCoV-OC43 antibody titres increased until days 15-21 and then plateaued until day 46. However, IgG titres against HCoV-NL63, -229E, and -HKU1 showed no significant increase. A two-way cross-reactivity was identified between SARS-CoV-2 and HCoV-OC43. Neutralizing antibodies against SARS-CoV-2 were not detectable in healthy controls who were positive for HCoV-OC43 S-IgG. HCoV-OC43 S-IgG titres were significantly higher in patients with severe disease than those in mild patients at days 1-21 post symptom onset (PSO). Higher levels of HCoV-OC43 S-IgG were also observed in patients requiring mechanical ventilation. At days 1-10 PSO, HCoV-OC43 S-IgG titres correlated to disease severity in the age group over 60. Our data indicate that there is a correlation between cross-reactive antibody against HCoV-OC43 spike protein and disease severity in COVID-19 patients.


Subject(s)
Antibodies, Viral/blood , COVID-19/immunology , Coronavirus OC43, Human/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Neutralizing/blood , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/pathology , Cross Reactions/immunology , Enzyme-Linked Immunosorbent Assay , Female , Humans , Immunoglobulin G/blood , Immunoglobulin G/immunology , Male , Middle Aged , Severity of Illness Index , Young Adult
14.
Sci Bull (Beijing) ; 66(12): 1215-1227, 2021 Jun 30.
Article in English | MEDLINE | ID: covidwho-1036223

ABSTRACT

Bat coronavirus (CoV) RaTG13 shares the highest genome sequence identity with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among all known coronaviruses, and also uses human angiotensin converting enzyme 2 (hACE2) for virus entry. Thus, SARS-CoV-2 is thought to have originated from bat. However, whether SARS-CoV-2 emerged from bats directly or through an intermediate host remains elusive. Here, we found that Rhinolophus affinis bat ACE2 (RaACE2) is an entry receptor for both SARS-CoV-2 and RaTG13, although the binding of RaACE2 to the receptor-binding domain (RBD) of SARS-CoV-2 is markedly weaker than that of hACE2. We further evaluated the receptor activities of ACE2s from additional 16 diverse animal species for RaTG13, SARS-CoV, and SARS-CoV-2 in terms of S protein binding, membrane fusion, and pseudovirus entry. We found that the RaTG13 spike (S) protein is significantly less fusogenic than SARS-CoV and SARS-CoV-2, and seven out of sixteen different ACE2s function as entry receptors for all three viruses, indicating that all three viruses might have broad host rages. Of note, RaTG13 S pseudovirions can use mouse, but not pangolin ACE2, for virus entry, whereas SARS-CoV-2 S pseudovirions can use pangolin, but not mouse, ACE2 enter cells efficiently. Mutagenesis analysis revealed that residues 484 and 498 in RaTG13 and SARS-CoV-2 S proteins play critical roles in recognition of mouse and human ACE2s. Finally, two polymorphous Rhinolophous sinicus bat ACE2s showed different susceptibilities to virus entry by RaTG13 and SARS-CoV-2 S pseudovirions, suggesting possible coevolution. Our results offer better understanding of the mechanism of coronavirus entry, host range, and virus-host coevolution.

15.
SciFinder; 2020.
Preprint | SciFinder | ID: ppcovidwho-4971

ABSTRACT

Objective To observe the effect of peroxyacetic acid in the laboratoiy disinfection of SARS-CoV-2 nucleic acid detection, and to provide a reference for laboratoiy prevention and control of SARS-CoV-2 detection. Methods Using gene detection technol. the effectiveness of compound peroxyacetic acid disinfectant in sterilizing laboratoiy for SARS-CoV-2 was evaluated. Results The compound peroxyacetic acid contained about 2.5 g/L of peroxyacetic acid and 60 g/L of hydrogen peroxide. The stock solution was used in an aerosol elec. sprayer at a dosage of 22 mL/m3 in a specimen preparation room of laboratoiy for SARS-CoV-2 nucleic acid detection. Spraying disinfection was conducted and the room was sealed for 60 min. The laboratory had been spray - sterilized at the end of each work for 30 consecutive days, and all collected laboratoiy environmental specimens have not detected the pos. SARS-CoV-2 nucleic acid and there had never been any incident of staff infection with SARS-CoV-2. Conclusion The results prove that spray disinfection of laboratoiy for SARS-CoV-2 detection with the compound peroxyacetic acid can effectively kill the SARS-CoV-2 in laboratoiy environment and can effectively protect the safety of staff.

16.
PLoS One ; 15(12): e0243890, 2020.
Article in English | MEDLINE | ID: covidwho-992703

ABSTRACT

OBJECTIVE: This study aimed to investigate the anxiety levels of healthcare workers and to provide guidance on potential accurate social and psychological interventions for healthcare workers during the epidemic of COVID-19 in Zhejiang Province, China. METHODS: Healthcare workers from five hospitals in Zhejiang Province were randomly selected into this study. Zung Self-Assessment Scale for Anxiety (SAS) was used to evaluate the anxiety status of the included 1637 healthcare workers. RESULTS: The total anxiety score of healthcare workers in Zhejiang Province was 30.85 ± 6.89. The univariate analysis showed that the anxiety level of healthcare workers was related to gender, education, occupation, physical condition, job risk coefficient, and with family members on the first-line combating COVID-19 (P <0.05). The multivariate analysis showed that physical condition and job risk coefficient were predictors of anxiety levels of healthcare workers. CONCLUSIONS: During the epidemic of COVID-19, 1637 healthcare workers generally had an increased tendency to have anxiety. Individualized assessment of the anxiety level of healthcare workers should be provided, and different interventions should be given based on the evaluation results.


Subject(s)
Anxiety/psychology , COVID-19/epidemiology , Pandemics , SARS-CoV-2/pathogenicity , Adult , Anxiety/virology , COVID-19/psychology , Female , Health Personnel/psychology , Humans , Male , Middle Aged , Occupational Exposure , Stress, Psychological/epidemiology
17.
Animal Model Exp Med ; 3(1): 93-97, 2020 Mar.
Article in English | MEDLINE | ID: covidwho-847791

ABSTRACT

BACKGROUND: Since December 2019, an outbreak of the Corona Virus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2) in Wuhan, China, has become a public health emergency of international concern. The high fatality of aged cases caused by SARS-CoV-2 was a need to explore the possible age-related phenomena with non-human primate models. METHODS: Three 3-5 years old and two 15 years old rhesus macaques were intratracheally infected with SARS-CoV-2, and then analyzed by clinical signs, viral replication, chest X-ray, histopathological changes and immune response. RESULTS: Viral replication of nasopharyngeal swabs, anal swabs and lung in old monkeys was more active than that in young monkeys for 14 days after SARS-CoV-2 challenge. Monkeys developed typical interstitial pneumonia characterized by thickened alveolar septum accompanied with inflammation and edema, notably, old monkeys exhibited diffuse severe interstitial pneumonia. Viral antigens were detected mainly in alveolar epithelial cells and macrophages. CONCLUSION: SARS-CoV-2 caused more severe interstitial pneumonia in old monkeys than that in young monkeys. Rhesus macaque models infected with SARS-CoV-2 provided insight into the pathogenic mechanism and facilitated the development of vaccines and therapeutics against SARS-CoV-2 infection.

19.
Nat Commun ; 11(1): 4528, 2020 09 10.
Article in English | MEDLINE | ID: covidwho-759594

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spreads worldwide and leads to an unprecedented medical burden and lives lost. Neutralizing antibodies provide efficient blockade for viral infection and are a promising category of biological therapies. Here, using SARS-CoV-2 spike receptor-binding domain (RBD) as a bait, we generate a panel of humanized single domain antibodies (sdAbs) from a synthetic library. These sdAbs reveal binding kinetics with the equilibrium dissociation constant (KD) of 0.99-35.5 nM. The monomeric sdAbs show half maximal neutralization concentration (EC50) of 0.0009-0.07 µg/mL and 0.13-0.51 µg/mL against SARS-CoV-2 pseudotypes, and authentic SARS-CoV-2, respectively. Competitive ligand-binding experiments suggest that the sdAbs either completely block or significantly inhibit the association between SARS-CoV-2 RBD and viral entry receptor ACE2. Fusion of the human IgG1 Fc to sdAbs improve their neutralization activity by up to ten times. These results support neutralizing sdAbs as a potential alternative for antiviral therapies.


Subject(s)
Antibodies, Neutralizing/immunology , Coronavirus Infections/virology , Pneumonia, Viral/virology , Single-Domain Antibodies/immunology , Spike Glycoprotein, Coronavirus/immunology , Angiotensin-Converting Enzyme 2 , Animals , Antibodies, Neutralizing/pharmacology , COVID-19 , Chlorocebus aethiops , Coronavirus Infections/drug therapy , HEK293 Cells , Humans , Immunoglobulin G , Models, Molecular , Pandemics , Peptidyl-Dipeptidase A/metabolism , Pneumonia, Viral/drug therapy , Protein Binding , Receptors, Virus/immunology , Single-Domain Antibodies/pharmacology , Spike Glycoprotein, Coronavirus/metabolism , Vero Cells
20.
Nature ; 583(7818): 830-833, 2020 07.
Article in English | MEDLINE | ID: covidwho-220333

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of coronavirus disease 2019 (COVID-19), which has become a public health emergency of international concern1. Angiotensin-converting enzyme 2 (ACE2) is the cell-entry receptor for severe acute respiratory syndrome coronavirus (SARS-CoV)2. Here we infected transgenic mice that express human ACE2 (hereafter, hACE2 mice) with SARS-CoV-2 and studied the pathogenicity of the virus. We observed weight loss as well as virus replication in the lungs of hACE2 mice infected with SARS-CoV-2. The typical histopathology was interstitial pneumonia with infiltration of considerable numbers of macrophages and lymphocytes into the alveolar interstitium, and the accumulation of macrophages in alveolar cavities. We observed viral antigens in bronchial epithelial cells, macrophages and alveolar epithelia. These phenomena were not found in wild-type mice infected with SARS-CoV-2. Notably, we have confirmed the pathogenicity of SARS-CoV-2 in hACE2 mice. This mouse model of SARS-CoV-2 infection will be valuable for evaluating antiviral therapeutic agents and vaccines, as well as understanding the pathogenesis of COVID-19.


Subject(s)
Betacoronavirus/pathogenicity , Coronavirus Infections/pathology , Coronavirus Infections/virology , Lung/pathology , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Pneumonia, Viral/pathology , Pneumonia, Viral/virology , Transgenes , Angiotensin-Converting Enzyme 2 , Animals , Antigens, Viral/immunology , Antigens, Viral/metabolism , Betacoronavirus/immunology , Betacoronavirus/metabolism , Bronchi/pathology , Bronchi/virology , COVID-19 , Coronavirus Infections/immunology , Disease Models, Animal , Epithelial Cells/pathology , Epithelial Cells/virology , Female , Humans , Immunoglobulin G/immunology , Lung/immunology , Lung/virology , Lymphocytes/immunology , Macrophages, Alveolar/immunology , Macrophages, Alveolar/virology , Male , Mice , Mice, Transgenic , Pandemics , Pneumonia, Viral/immunology , Receptors, Complement 3d/genetics , Receptors, Complement 3d/metabolism , SARS-CoV-2 , Virus Replication , Weight Loss
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