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1.
Emerg Microbes Infect ; 11(1): 1920-1935, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-1908682

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and related sarbecoviruses enter host cells by receptor-recognition and membrane-fusion. An indispensable step in fusion is the formation of 6-helix bundle by viral spike heptad repeats 1 and 2 (HR1 and HR2). Here, we report the construction of 5-helix bundle (5HB) proteins for virus infection inhibition. The optimal construct inhibits SARS-CoV-2 pseudovirus entry with sub-micromolar IC50. Unlike HR2-based peptides that cannot bind spike in the pre-fusion conformation, 5HB features with the capability of binding to pre-fusion spike. Furthermore, 5HB binds viral HR2 at both serological- and endosomal-pH, highlighting its entry-inhibition capacity when SARS-CoV-2 enters via either cell membrane fusion or endosomal route. Finally, we show that 5HB could neutralize S-mediated entry of the predominant SARS-CoV-2 variants and a wide spectrum of sarbecoviruses. These data provide proof-of-concept evidence that 5HB might be developed for the prevention and treatment of SARS-CoV-2 and other emerging sarbecovirus infections.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Hydrogen-Ion Concentration , Membrane Glycoproteins/metabolism , Spike Glycoprotein, Coronavirus/chemistry , Viral Envelope Proteins/metabolism , Virus Internalization
3.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-321371

ABSTRACT

Background The long-term consequences of human umbilical cord-derived mesenchymal stem cell (UC-MSC) treatment for COVID-19 patients are yet to be reported. This study assessed the 1-year outcomes in patients with severe COVID-19, who were recruited in our previous UC-MSC clinical trial.Methods: In this prospective, longitudinal, cohort study, 100 patients enrolled in our phase 2 trial were prospectively followed up at 3-month intervals for 1 year to evaluate the long-term safety and effectiveness of UC-MSC treatment. The primary endpoint was an altered proportion of whole-lung lesion volumes measured by high-resolution CT. Other imaging outcomes, 6-minute walking distance (6-MWD), lung function, plasma biomarkers, and adverse events were also recorded and analyzed. This trial was registered with ClinicalTrials.gov (NCT04288102).Findings: Within 3 months, MSC administration exerted numerical improvement in whole-lung lesion volume compared with the placebo, leading to a significant difference of −10.82% (95% CI: −20.69%, −1.46%, P=0.030) on day 10. MSC also reduced the proportion of solid component lesion volume compared with the placebo at each follow-up point, with a significant difference of − 9.02% (95%CI: − 17.44%, − 0.10%, P=0.045) at month 9. More interestingly, 17.86% (10/56) of patients in the MSC group had normal CT images at month 12 ( P= 0.013), but none in the placebo group. The incidence of symptoms was lower in the MSC group than in the placebo group at each follow-up time, particularly sleep difficulties at month 3 (OR 0.19, 95% CI 0.07,0.50;P=0.001), and usual activity at month 12 (OR 0.15, 95% CI 0.03,0.79;P=0.018). Neutralizing antibodies were all positive, with a similar median inhibition rate (61.6% vs. 67.55%) in both groups at month 12. No difference in adverse events at the 1-year follow-up and tumor markers at month 12 were observed between the two groups.Interpretation: UC-MSC administration achieves a long-term benefit in the recovery of lung lesions and symptoms in COVID-19 patients.Trial Registration: This trial was registered with ClinicalTrials.gov (NCT04288102).Funding The National Key R&D Program of China, the Innovation Groups of the National Natural Science Foundation of China, and the National Science and Technology Major Project.Declaration of Interest: None to declare. Ethical Approval: This study was approved by the Ethics Committee of the Fifth Medical Center, Chinese PLA General Hospital (2020-013-D).

4.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-321366

ABSTRACT

Background: Treatment of severe Corona Virus Disease 2019 (COVID-19) is challenging. We performed a phase 2 trial to assess the efficacy and safety of human umbilical cord-mesenchymal stem cells (UC‑MSCs) to treat patients with severe COVID-19 with lung damage, based on our phase 1 data.Methods: In this randomised, double-blind, and placebo-controlled trial, we recruited 101 eligible patients with severe COVID-19 with lung damage aged between 18–74 years from two hospitals. Enrolled patients were randomly assigned at a 2:1 ratio to receive either UC-MSCs (4 × 107 cells per infusion) or placebo on day 0, 3, and 6. We excluded patients with malignant tumours, shock, or other organ failure. The primary endpoint was an altered proportion of whole lung lesion areas from baseline to day 28, measured by chest computed tomography. Other imaging outcomes, 6-minute walk test, maximum vital capacity, diffusing capacity, plasma biomarkers, and adverse events were recorded and analysed. Primary analysis was done in the modified intention-to-treat (mITT) population and safety analysis was done in all patients who started their assigned treatment. Findings: From March 5, 2020, to March 28, 2020, 100 patients were finally enrolled and received either UC-MSCs (n = 65) or placebo (n = 35). During follow-up, the patients receiving UC-MSCs exhibited a trend of numerical improvement in whole lung lesions from baseline to day 28 compared with the placebo cases. UC-MSCs administration significantly reduced the proportions of consolidation lesions from baseline to day 28 in the treated patients compared with the placebo subjects. The 6-minute walk test showed an increased distance in patients treated with UC-MSCs. Notably, UC-MSCs delivery was well tolerated, with no serious adverse events.Interpretation: UC-MSCs treatment is a safe and potentially effective therapeutic approach for patients with severe COVID‑19. The trial suggests that UC-MSCs administration might benefit patients with COVID-19 with lung damage at the convalescent stage as well as the progression stage.Trial Registration: This trial is registered with ClinicalTrials.gov, number NCT04288102.Funding Statement: This trial was supported by The National Key R&D Program of China (2020YFC0841900, 2020YFC0844000, 2020YFC08860900);The Innovation Groups of the National Natural Science Foundation of China (81721002);The National Science and Technology Major Project (2017YFA0105703).Declaration of Interests: All authors declare no competing interests.Ethics Approval Statement: Ethical approval was obtained from the institutional review boards of each participating hospital. Written informed consent was obtained from all the enrolled patients or their legal representatives if they were unable to provide consent.

5.
EBioMedicine ; 75: 103789, 2022 Jan.
Article in English | MEDLINE | ID: covidwho-1587925

ABSTRACT

BACKGROUND: The long-term consequences of human umbilical cord-derived mesenchymal stem cell (UC-MSC) treatment for COVID-19 patients are yet to be reported. This study assessed the 1-year outcomes in patients with severe COVID-19, who were recruited in our previous UC-MSC clinical trial. METHODS: In this prospective, longitudinal, cohort study, 100 patients enrolled in our phase 2 trial were prospectively followed up at 3-month intervals for 1 year to evaluate the long-term safety and effectiveness of UC-MSC treatment. The primary endpoint was an altered proportion of whole-lung lesion volumes measured by high-resolution CT. Other imaging outcomes, 6 min walking distance (6-MWD), lung function, plasma biomarkers, and adverse events were also recorded and analyzed. This trial was registered with ClinicalTrials.gov (NCT04288102). FINDINGS: MSC administration improved in whole-lung lesion volume compared with the placebo with a difference of -10.8% (95% CI: -20.7%, -1.5%, p = 0.030) on day 10. MSC also reduced the proportion of solid component lesion volume compared with the placebo at each follow-up point. More interestingly, 17.9% (10/56) of patients in the MSC group had normal CT images at month 12, but none in the placebo group (p = 0.013). The incidence of symptoms was lower in the MSC group than in the placebo group at each follow-up time. Neutralizing antibodies were all positive, with a similar median inhibition rate (61.6% vs. 67.6%) in both groups at month 12. No difference in adverse events at the 1-year follow-up and tumor markers at month 12 were observed between the two groups. INTERPRETATION: UC-MSC administration achieves a long-term benefit in the recovery of lung lesions and symptoms in COVID-19 patients. FUNDING: The National Key R&D Program of China, the Innovation Groups of the National Natural Science Foundation of China, and the National Science and Technology Major Project.


Subject(s)
COVID-19/therapy , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Aged , Allografts , Double-Blind Method , Female , Follow-Up Studies , Humans , Male , Middle Aged , Patient Acuity
6.
Life (Basel) ; 11(12)2021 Dec 09.
Article in English | MEDLINE | ID: covidwho-1572550

ABSTRACT

The SARS-CoV-2 virus is deadly, contagious, can cause COVID-19 disease, and endangers public health and safety. The development of SARS-CoV-2 inactivation technology is crucial and imminent in current pandemic period. Neutron radiation is usually used to sterilize viruses because neutron radiation is 10 times more effective than gamma-rays in inactivating viruses. In this work we established a closed SARS-CoV-2 inactivation container model by the Monte Carlo method and simulated the inactivation performance by using several different neutrons sources. To study the effects of inactivation container factors, including the reflector thickness, the type of the reflector material, the SARS-CoV-2 layer area and the distance from the radiation source on the energy deposition of a single neutron particle in SARS-CoV-2 sample, we simulated the neutron energy deposition on a SARS-CoV-2 sample. The simulation results indicate that the saturated thicknesses of reflector materials for graphite, water and paraffin are approximately 30 cm, 15 cm, and 10 cm, respectively, and the energy deposition (radiation dose) becomes larger when the SARS-CoV-2 layer area is smaller and the SARS-CoV-2 layer is placed closer to the neutron source. The calculated single-neutron energy deposition on 10 × 10 cm2 SARS-CoV-2 layer is about 3.0059 × 10-4 MeV/g with graphite as the reflection layer, when the 14 MeV neutron source intensity is 1012 n/s and the SARS-CoV-2 layer is 5 cm away from the neutron source. If the lethal dose of SARS-CoV-2 is assumed as the IAEA recommended reference dose, 25 kGy, the SARS-CoV-2 could be decontaminated in about 87 min, and the sterilization time could be less than 52 s if the 14 MeV neutron intensity is increased to 1014 n/s.

7.
Antiviral research ; 2021.
Article in English | EuropePMC | ID: covidwho-1505389

ABSTRACT

Vaccination and administration of monoclonal antibody cocktails are effective tools to control the progression of infectious diseases and to terminate pandemics such as COVID-19. However, the emergence of SARS-CoV-2 mutants with enhanced transmissibility and altered antigenicity requires broad-spectrum therapies. Here we developed a panel of SARS-CoV-2 specific mouse monoclonal antibodies (mAbs), and characterized them based on ELISA, Western immunoblot, isotyping, and virus neutralization. Six neutralizing mAbs that exhibited high-affinity binding to SARS-CoV-2 spike protein were identified, and their amino acid sequences were determined by mass spectrometry. Functional assays confirmed that three mAbs, F461G11, F461G15, and F461G16 neutralized four variants of concern (VOC): B.1.1.7 (alpha), B.1.351 (beta), P.1 (gamma) and B.1.617.2 (delta) These mAbs are promising candidates for COVID-19 therapy, and understanding their interactions with virus spike protein should support further vaccine and antibody development.

8.
Association for Computing Machinery. Communications of the ACM ; 64(8):39, 2021.
Article in English | ProQuest Central | ID: covidwho-1352584

ABSTRACT

The sudden disruption brought to our world by COVID-19 has put science and research at the center of the public attention. Scientists have been asked why the pandemic developed, how it may be countered and possibly defeated, and how its spread could be prevented. Almost all branches of science have been involved: from health to social sciences, from economics to technological sciences. Computer science was no exception. Researchers know how to communicate with peers. They learn how to do it since they enter a Ph.D. program, and continue to learn and improve throughout their career. Research is an intrinsically open process that relies on communication among peers. The main ambition of scientists is to achieve novel results and disseminate them to the world, contributing to the advance of human knowledge and welfare. COVID-19 brought science back on stage in the spotlight, emerging from the shaded "death of expertise" corner. Science and technology proved to be decisive weapons to fight against the virus.

9.
Signal Transduct Target Ther ; 6(1): 58, 2021 02 10.
Article in English | MEDLINE | ID: covidwho-1078577

ABSTRACT

Treatment of severe Coronavirus Disease 2019 (COVID-19) is challenging. We performed a phase 2 trial to assess the efficacy and safety of human umbilical cord-mesenchymal stem cells (UC-MSCs) to treat severe COVID-19 patients with lung damage, based on our phase 1 data. In this randomized, double-blind, and placebo-controlled trial, we recruited 101 severe COVID-19 patients with lung damage. They were randomly assigned at a 2:1 ratio to receive either UC-MSCs (4 × 107 cells per infusion) or placebo on day 0, 3, and 6. The primary endpoint was an altered proportion of whole lung lesion volumes from baseline to day 28. Other imaging outcomes, 6-minute walk test (6-MWT), maximum vital capacity, diffusing capacity, and adverse events were recorded and analyzed. In all, 100 COVID-19 patients were finally received either UC-MSCs (n = 65) or placebo (n = 35). UC-MSCs administration exerted numerical improvement in whole lung lesion volume from baseline to day 28 compared with the placebo (the median difference was -13.31%, 95% CI -29.14%, 2.13%, P = 0.080). UC-MSCs significantly reduced the proportions of solid component lesion volume compared with the placebo (median difference: -15.45%; 95% CI -30.82%, -0.39%; P = 0.043). The 6-MWT showed an increased distance in patients treated with UC-MSCs (difference: 27.00 m; 95% CI 0.00, 57.00; P = 0.057). The incidence of adverse events was similar in the two groups. These results suggest that UC-MSCs treatment is a safe and potentially effective therapeutic approach for COVID-19 patients with lung damage. A phase 3 trial is required to evaluate effects on reducing mortality and preventing long-term pulmonary disability. (Funded by The National Key R&D Program of China and others. ClinicalTrials.gov number, NCT04288102.


Subject(s)
COVID-19/therapy , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , SARS-CoV-2 , Umbilical Cord , Aged , Allografts , COVID-19/mortality , COVID-19/physiopathology , Double-Blind Method , Female , Humans , Male , Middle Aged , Treatment Outcome
11.
Signal Transduct Target Ther ; 5(1): 172, 2020 08 27.
Article in English | MEDLINE | ID: covidwho-733534

ABSTRACT

No effective drug treatments are available for coronavirus disease 2019 (COVID-19). Host-directed therapies targeting the underlying aberrant immune responses leading to pulmonary tissue damage, death, or long-term functional disability in survivors require clinical evaluation. We performed a parallel assigned controlled, non-randomized, phase 1 clinical trial to evaluate the safety of human umbilical cord-derived mesenchymal stem cells (UC-MSCs) infusions in the treatment of patients with moderate and severe COVID-19 pulmonary disease. The study enrolled 18 hospitalized patients with COVID-19 (n = 9 for each group). The treatment group received three cycles of intravenous infusion of UC-MSCs (3 × 107 cells per infusion) on days 0, 3, and 6. Both groups received standard COVID-treatment regimens. Adverse events, duration of clinical symptoms, laboratory parameters, length of hospitalization, serial chest computed tomography (CT) images, the PaO2/FiO2 ratio, dynamics of cytokines, and IgG and IgM anti-SARS-CoV-2 antibodies were analyzed. No serious UC-MSCs infusion-associated adverse events were observed. Two patients receiving UC-MSCs developed transient facial flushing and fever, and one patient developed transient hypoxia at 12 h post UC-MSCs transfusion. Mechanical ventilation was required in one patient in the treatment group compared with four in the control group. All patients recovered and were discharged. Our data show that intravenous UC-MSCs infusion in patients with moderate and severe COVID-19 is safe and well tolerated. Phase 2/3 randomized, controlled, double-blinded trials with long-term follow-up are needed to evaluate the therapeutic use of UC-MSCs to reduce deaths and improve long-term treatment outcomes in patients with serious COVID-19.


Subject(s)
Antibodies, Viral/blood , Betacoronavirus/immunology , Cord Blood Stem Cell Transplantation/methods , Coronavirus Infections/therapy , Hematopoietic Stem Cells/virology , Mesenchymal Stem Cell Transplantation/methods , Pneumonia, Viral/therapy , Adult , Antiviral Agents/therapeutic use , Betacoronavirus/drug effects , Betacoronavirus/pathogenicity , COVID-19 , Coronavirus Infections/immunology , Coronavirus Infections/pathology , Coronavirus Infections/virology , Drug Combinations , Female , Glucocorticoids/therapeutic use , Hematopoietic Stem Cells/drug effects , Hematopoietic Stem Cells/immunology , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Lopinavir , Male , Middle Aged , Pandemics , Pneumonia, Viral/immunology , Pneumonia, Viral/pathology , Pneumonia, Viral/virology , Respiration, Artificial , Ritonavir , SARS-CoV-2 , Severity of Illness Index , Treatment Outcome
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