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1.
Cell Rep ; 39(5): 110757, 2022 05 03.
Article in English | MEDLINE | ID: covidwho-1850799

ABSTRACT

Although the antibody response to COVID-19 vaccination has been studied extensively at the polyclonal level using immune sera, little has been reported on the antibody response at the monoclonal level. Here, we isolate a panel of 44 anti-SARS-CoV-2 monoclonal antibodies (mAbs) from an individual who received two doses of the ChAdOx1 nCoV-19 (AZD1222) vaccine at a 12-week interval. We show that, despite a relatively low serum neutralization titer, Spike-reactive IgG+ B cells are still detectable 9 months post-boost. Furthermore, mAbs with potent neutralizing activity against the current SARS-CoV-2 variants of concern (Alpha, Gamma, Beta, Delta, and Omicron) are present. The vaccine-elicited neutralizing mAbs form eight distinct competition groups and bind epitopes overlapping with neutralizing mAbs elicited following SARS-CoV-2 infection. AZD1222-elicited mAbs are more mutated than mAbs isolated from convalescent donors 1-2 months post-infection. These findings provide molecular insights into the AZD1222 vaccine-elicited antibody response.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Monoclonal , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines , Humans , Vaccination
2.
Trials ; 23(1): 263, 2022 Apr 05.
Article in English | MEDLINE | ID: covidwho-1779666

ABSTRACT

BACKGROUND: Antiretroviral therapy (ART) has led to dramatic improvements in survival for people living with HIV, but is unable to cure infection, or induce viral control off therapy. Designing intervention trials with novel agents with the potential to confer a period of HIV remission without ART remains a key scientific and community goal. We detail the rationale, design, and outcomes of a randomised, placebo-controlled trial of two HIV-specific long-acting broadly neutralising antibodies (bNAbs): 3BNC117-LS and 10-1074-LS, which target CD4 binding site and V3 loop respectively, on post-treatment viral control. METHODS: RIO is a randomised, placebo-controlled, double-blinded prospective phase II study. Eligible individuals will have started ART within 3 months of primary HIV infection and have viral sequences that appear to be sensitive to both bNAbs. It will randomise 72 eligible participants 1:1 to the following arms via a two-stage design. In Stage 1, arm A participants are given dual long-acting (LS-variants) bNAbs infusions, followed by intensively monitored Analytical Treatment Interruption (ATI) (n = 36); in arm B, participants receive placebo infusions followed by ATI. The primary endpoint will be time to viral rebound within 36 weeks after ATI. Upon viral rebound, the participant and researcher are unblinded. Participants in arm A recommence ART and complete the study. Participants in arm B are invited to restart ART and enroll into Stage 2 where they will receive open-label LS bNAbs, followed by a second ATI 24 weeks after. Secondary and exploratory endpoints include adverse events, time to undetectable viraemia after restarting ART, immunological markers, HIV proviral DNA, serum bNAb concentrations in blood, bNAb resistance at viral rebound, and quality of life measures. DISCUSSION: The two-stage design was determined in collaboration with community involvement. This design allows all participants the option to receive bNAbs. It also tests the hypothesis that bNAbs may drive sustained HIV control beyond the duration of detectable bNAb concentrations. Community representatives were involved at all stages. This included the two-stage design, discussion on the criteria to restart ART, frequency of monitoring visits off ART, and reducing the risk of onward transmission to HIV-negative partners. It also included responding to the challenges of COVID-19. TRIAL REGISTRATION: The protocol is registered on Clinical. TRIALS: gov and EudraCT and has approval from UK Ethics and MHRA.


Subject(s)
COVID-19 , HIV Infections , HIV-1 , Broadly Neutralizing Antibodies , Clinical Trials, Phase II as Topic , Community Participation , HIV Antibodies , HIV Infections/diagnosis , HIV Infections/drug therapy , Humans , Prospective Studies , Quality of Life , Randomized Controlled Trials as Topic , SARS-CoV-2 , Treatment Outcome
4.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-315019

ABSTRACT

• Background: Antiretroviral therapy (ART) has led to dramatic improvements in survival for people living with HIV, but is unable to cure infection, or induce viral control off therapy. Designing intervention trials with novel agents with the potential to confer a period of HIV remission without ART, remains a key scientific and community goal. We detail the rationale, design, and outcomes of a randomised, placebo-controlled trial of two HIV-specific long-acting broadly neutralising antibodies (bNAbs);3BNC117-LS and 10-1074-LS, which target CD4 binding site and V3 loop respectively, on post-treatment viral control.• Methods: RIO is a randomised, placebo-controlled, double-blinded prospective phase II study. Eligible individuals will have started ART within 3 months of primary HIV infection and have viral sequences that appear to be sensitive to both bNAbs. It will randomise 72 eligible participants 1:1 to the following arms via a two-stage design. In stage 1, arm A participants are given dual long-acting (LS-variants) bNAbs infusions, followed by intensively monitored Analytical Treatment Interruption (ATI) (n=36);in arm B, participants receive placebo infusions followed by ATI. The primary endpoint will be time to viral rebound within 36 weeks after ATI. Upon viral rebound, the participant and researcher are unblinded. Participants in arm A recommence ART and complete the study. Participants in arm B are invited to restart ART and enroll into stage 2 where they will receive open-label LS bNAbs, followed by a second ATI 24 weeks after. Secondary and exploratory endpoints include adverse events, time to undetectable viraemia after re-starting ART, immunological markers, HIV proviral DNA, serum bNAb concentrations in blood, bNAb resistance at viral rebound, and quality of life measures.• Discussion: The two-stage design was determined in collaboration with community involvement. This design allows all participants the option to receive bNAbs. It also tests the hypothesis that bNAbs may drive sustained HIV-control beyond the duration of detectable bNAb concentrations. Community representatives were involved at all stages. This included the two-stage design, discussion on the criteria to restart ART, frequency of monitoring visits off ART and reducing the risk of onward transmission to HIV-negative partners. It also included responding to the challenges of COVID-19. Trial registration : The protocol is registered on Clinical.trials.gov and EudraCT and has approval from UK Ethics and MHRA.

5.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-315017

ABSTRACT

Background: It is unclear from epidemiological data for COVID-19 infections, whether people living with HIV (PLWH) have a different outcomes compared to the general population. We conducted a multi-centre, retrospective matched cohort study of SARS-CoV-2 PCR-positive hospital inpatients analysed by HIV-status.Methods: HIV-negative patients were matched to PLWH admitted to hospital before 31 st May 2020, with a 3:1 ratio by: hospital site, SARS-CoV-2 test date +/- 7 days, age +/- 5 years, gender, and index of multiple deprivation decile (IMDD) +/- 1. The primary objective was clinical improvement (≥2-point improvement on a 7-point ordinal scale) or hospital discharge by day 28, whichever was earlier.Results: 68 PLWH and 181 HIV-negative comparators were included. After adjustment for ethnicity, frailty, baseline hypoxia, duration of symptoms prior to baseline, body mass index categories, and comorbidities (hypertension, chronic cardiac disease, chronic lung disease, active malignancy, diabetes, and chronic renal disease), the effect size of HIV status was not associated with time to clinical improvement or discharge from hospital (aHR 0.70, 95%CI 0.43, 1.17;p=0.18), despite unadjusted hazards of PLWH achieving the primary outcome being 43% lower (p=0.005). Baseline frailty (aHR=0.79;95%CI 0.65, 0.95;p=0.011), malignancy (aHR=0.37;95%CI 0.17, 0.82;p=0.014) remained associated with poorer outcomes. PLWH were more likely of black and minority ethnicities (75.0% vs 48.6%, p=0.0002), higher median clinical frailty score (3 IQR 2-5 vs 2 IQR 1-4, p=0.0069), higher proportion of active malignancy (14.4% vs 9.9%, p=0.29). Median body mass index (BMI) was lower amongst PLWH (27.7 IQR 23.9-32.3 vs 29.4 IQR 24.7-34.3, p=0.19). Median CD4 count of PLWH was 352cells/µL (IQR 235-619) and 95.7% had suppressed viral loads <200copies/mL, 63/68 (92.3%) were taking antiretroviral therapy.Conclusions: Differences in clinical outcomes of COVID-19 hospitalisations in PLWH may be due to other important factors including increased frailty and comorbidities such as malignancies, rather than HIV-status alone.Funding Statement: This study has not received any funding sources.Declaration of Interests: MJL has received grants and honoraria from Gilead Sciences and Viiv Healthcare not related to this work. SF has received research grants to her institution from NIH, MRC, BMGF. JT has received support for virtual conference registration from ViiV Healthcare and research grants from the Medical Research Council and the British HIV Association not related to this work. CvH has received educational grants, conference support and advisory board fees from ViiV Healthcare, Gilead Sciences, MSC not related to this work. MP reports grants and personal fees from Gilead Sciences and personal fees from QIAGEN, outside the submitted work. MP is supported by a NIHR Development and Skills Enhancement Award (NIHR301192) and in receipt of funding from UKRI / MRC (MR/V027549/1). He acknowledges the support from UKRI, the NIHR Leicester BRC and NIHR ARC East Midlands. No other competing interests, financial relationships with any organisations that might have an interest in the submitted work, or other relationships or activities that could appear to have influenced the submitted work have been reported by other authors.Ethics Approval Statement: Ethical approval was granted by the UK Health Research Authority (REC reference 20/HRA/2278).

6.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-310655

ABSTRACT

Background: The ChAdOx1 nCoV-19 (AZD1222) vaccine is immunogenic and protects against COVID-19. However, data on vaccine immunogenicity are needed for the 40 million people living with HIV (PWH), who may have less functional immunity and more associated co-morbidities than the general population. Methods: Between the 5th and 24th November 2020, 54 adults with HIV, aged 18-55 years, were enrolled into a single arm open label vaccination study within the protocol of the larger phase 2/3 COV002 trial. A prime-boost regimen of ChAdOx1 nCoV-19, with two doses (5 × 1010 vp) was given 4-6 weeks apart. All participants were on antiretroviral therapy (ART) with undetectable plasma HIV viral loads and CD4+ T cell counts >350 cells/µl at enrolment. Data were captured on adverse events. Humoral responses were measured by anti-spike IgG ELISA and antibody-mediated live virus neutralisation. Cell-mediated immune responses were measured by ex-vivo interferon-γ enzyme-linked immunospot assay (ELISpot) and T cell proliferation. All outcomes were compared with a HIV uninfected group from the main COV002 study.Findings: 54 participants with HIV (median age 42.5 years (IQR 37.2-49.8)) received two doses of ChAdOx1 nCoV-19. Median CD4+ T cell count at enrolment was 694 cells/µl (IQR 562-864). Results are reported for 56 days of follow-up. Local and systemic reactions occurring during the first 7 days after prime vaccination included pain at the injection site (49%), fatigue (47%), headache (47%), malaise (34%), chills (23%), and muscle or (36%) joint pain (9%), the frequencies of which were similar to the HIV-negative participants. There were no serious adverse events. Anti-spike IgG responses by ELISA peaked at Day 42 (median 1440 ELISA units, IQR 704-2728) and were sustained out to Day 56. There was no correlation with CD4+ T cell count or age and the magnitude of the anti-spike IgG response at Day 56 (P>0.05 for both). ELISpot and T cell proliferative responses peaked between Day 14 and 28 after prime and were sustained through to Day 56. When compared to participants without HIV there was no statistical difference in magnitude or persistence of SARS-CoV-2 spike-specific humoral or cellular responses (P>0.05 for all analyses).Interpretation: In this study of PWH, vaccination with ChAdOx1 nCoV-19 was well tolerated and there was no difference in humoral and cell-mediated immune responses compared to an adult cohort without HIV who received the same vaccination regime. Trial Registration: Trial Registration number is NCT04400838. Funding: UK Research and Innovation, National Institutes for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midlands NIHR Clinical Research Network, and AstraZeneca. The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care.Declaration of Interest: Oxford University has entered into a partnership with AstraZeneca for further development of ChAdOx1 nCoV-19 (AZD1222). AstraZeneca reviewed the data from the study and the final manuscript before 474 submission, but the authors retained editorial control. SCG is cofounder of Vaccitech (a collaborator in the early development of this vaccine candidate) and named as an inventor on a patent covering use of ChAdOx1-vectored vaccines (PCT/GB2012/000467) and a patent application covering this SARS-CoV-2 vaccine. TL is named as an inventor on a patent application covering this SARS-CoV-2 vaccine and was consultant to Vaccitech. PMF is a consultant to Vaccitech. AJP is Chair of the UK Department of Health and Social Care’s JCVI, but does not participate in policy advice on coronavirus vaccines, and is a member of the WHO Strategic Advisory Group of Experts (SAGE). AVSH is a cofounder of and consultant to Vaccitech and is named as an inventor on a patent covering design and use of ChAdOx1-vectored vaccines (PCT/GB2012/0004 7).Ethical Approval: Written informed consent was obtained from all participants, and the trial was done in accordance with the principles of the Declaration of Helsinki and Good Clinical Practice. This study was approved in the UK by the Medicines and Healthcare products Regulatory Agency (reference 21584/0424/001-0001) and the South Central Berkshire Research Ethics Committee (reference 20/SC/0145). Vaccine use was authorised by Genetically Modified Organisms Safety Committees at each participating site.

7.
Non-conventional in English | MEDLINE, Grey literature | ID: grc-750513

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused millions of human infections and hundreds of thousands of deaths. Accordingly, an effective vaccine is of critical importance in mitigating coronavirus induced disease 2019 (COVID-19) and curtailing the pandemic. We developed a replication-competent vesicular stomatitis virus (VSV)-based vaccine by introducing a modified form of the SARS-CoV-2 spike gene in place of the native glycoprotein gene (VSV-eGFP-SARS-CoV-2). Immunization of mice with VSV-eGFP-SARS-CoV-2 elicits high titers of antibodies that neutralize SARS-CoV-2 infection and target the receptor binding domain that engages human angiotensin converting enzyme-2 (ACE2). Upon challenge with a human isolate of SARS-CoV-2, mice expressing human ACE2 and immunized with VSV-eGFP-SARS-CoV-2 show profoundly reduced viral infection and inflammation in the lung indicating protection against pneumonia. Finally, passive transfer of sera from VSV-eGFP-SARS-CoV-2-immunized animals protects naïve mice from SARS-CoV-2 challenge. These data support development of VSV-eGFP-SARS-CoV-2 as an attenuated, replication-competent vaccine against SARS-CoV-2.

8.
Non-conventional in English | [Unspecified Source], Grey literature | ID: grc-750512

ABSTRACT

Severe Acute Respiratory Syndrome Coronavirus -2 (SARS-CoV-2) emerged in late 2019 and has spread worldwide resulting in the Coronavirus Disease 2019 (COVID-19) pandemic. Although animal models have been evaluated for SARS-CoV-2 infection, none have recapitulated the severe lung disease phenotypes seen in hospitalized human cases. Here, we evaluate heterozygous transgenic mice expressing the human ACE2 receptor driven by the epithelial cell cytokeratin-18 gene promoter (K18-hACE2) as a model of SARS-CoV-2 infection. Intranasal inoculation of SARS-CoV-2 in K18-hACE2 mice results in high levels of viral infection in lung tissues with additional spread to other organs. Remarkably, a decline in pulmonary function, as measured by static and dynamic tests of respiratory capacity, occurs 4 days after peak viral titer and correlates with an inflammatory response marked by infiltration into the lung of monocytes, neutrophils, and activated T cells resulting in pneumonia. Cytokine profiling and RNA sequencing analysis of SARS-CoV-2-infected lung tissues show a massively upregulated innate immune response with prominent signatures of NF-kB-dependent, type I and II interferon signaling, and leukocyte activation pathways. Thus, the K18-hACE2 model of SARS-CoV-2 infection recapitulates many features of severe COVID-19 infection in humans and can be used to define the mechanistic basis of lung disease and test immune and antiviral-based countermeasures.

9.
HIV Med ; 23(2): 121-133, 2022 02.
Article in English | MEDLINE | ID: covidwho-1434702

ABSTRACT

BACKGROUND: The contribution of HIV to COVID-19 outcomes in hospitalized inpatients remains unclear. We conducted a multi-centre, retrospective matched cohort study of SARS-CoV-2 PCR-positive hospital inpatients analysed by HIV status. METHODS: HIV-negative patients were matched to people living with HIV (PLWH) admitted from 1 February 2020 to 31 May 2020 up to a 3:1 ratio by the following: hospital site, SARS-CoV-2 test date ± 7 days, age ± 5 years, gender, and index of multiple deprivation decile ± 1. The primary objective was clinical improvement (two-point improvement or better on a seven-point ordinal scale) or hospital discharge by day 28, whichever was earlier. RESULTS: A total of 68 PLWH and 181 HIV-negative comparators were included. In unadjusted analyses, PLWH had a reduced hazard of achieving clinical improvement or discharge [adjusted hazard ratio (aHR) = 0.57, 95% confidence interval (CI): 0.39-0.85, p = 0.005], but this association was ameliorated (aHR = 0.70, 95% CI: 0.43-1.17, p = 0.18) after additional adjustment for ethnicity, frailty, baseline hypoxaemia, duration of symptoms prior to baseline, body mass index (BMI) categories and comorbidities. Baseline frailty (aHR = 0.79, 95% CI: 0.65-0.95, p = 0.011), malignancy (aHR = 0.37, 95% CI 0.17, 0.82, p = 0.014) remained associated with poorer outcomes. The PLWH were more likely to be of black, Asian and minority ethnic background (75.0% vs 48.6%, p = 0.0002), higher median clinical frailty score [3 × interquartile range (IQR): 2-5 vs, 2 × IQR: 1-4, p = 0.0069), and to have a non-significantly higher proportion of active malignancy (14.4% vs 9.9%, p = 0.29). CONCLUSIONS: Adjusting for confounding comorbidities and demographics in a matched cohort ameliorated differences in outcomes of PLWH hospitalized with COVID-19, highlighting the importance of an appropriate comparison group when assessing outcomes of PLWH hospitalized with COVID-19.


Subject(s)
COVID-19 , HIV Infections , COVID-19/epidemiology , COVID-19/therapy , England/epidemiology , Female , HIV Infections/epidemiology , Hospitalization , Humans , Male , Pandemics , Retrospective Studies , Treatment Outcome
11.
Viruses ; 13(6)2021 05 31.
Article in English | MEDLINE | ID: covidwho-1256669

ABSTRACT

Identification of therapeutics against emerging and re-emerging viruses remains a continued priority that is only reinforced by the recent SARS-CoV-2 pandemic. Advances in monoclonal antibody (mAb) isolation, characterization, and production make it a viable option for rapid treatment development. While mAbs are traditionally screened and selected based on potency of neutralization in vitro, it is clear that additional factors contribute to the in vivo efficacy of a mAb beyond viral neutralization. These factors include interactions with Fc receptors (FcRs) and complement that can enhance neutralization, clearance of infected cells, opsonization of virions, and modulation of the innate and adaptive immune response. In this review, we discuss recent studies, primarily using mouse models, that identified a role for Fc-FcγR interactions for optimal antibody-based protection against emerging and re-emerging virus infections.


Subject(s)
Communicable Diseases, Emerging/immunology , Immunoglobulin Fc Fragments/immunology , Receptors, IgG/immunology , Virus Diseases/immunology , Viruses/immunology , Animals , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/therapeutic use , Antibodies, Neutralizing/immunology , Antibodies, Neutralizing/therapeutic use , Antibody-Dependent Cell Cytotoxicity , Communicable Diseases, Emerging/therapy , Communicable Diseases, Emerging/virology , Humans , Immunization, Passive , Phagocytosis , Virus Diseases/therapy , Virus Diseases/virology , Viruses/classification
12.
mSphere ; 5(5)2020 09 02.
Article in English | MEDLINE | ID: covidwho-742194

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected millions within just a few months, causing severe respiratory disease and mortality. Assays to monitor SARS-CoV-2 growth in vitro depend on time-consuming and costly RNA extraction steps, hampering progress in basic research and drug development efforts. Here, we developed a simplified quantitative real-time PCR assay that bypasses viral RNA extraction steps and can monitor SARS-CoV-2 growth from a small amount of cell culture supernatants. In addition, we show that this approach is easily adaptable to numerous other RNA and DNA viruses. Using this assay, we screened the activities of a number of compounds that were predicted to alter SARS-CoV-2 entry and replication as well as HIV-1-specific drugs in a proof-of-concept study. We found that E64D (inhibitor of endosomal proteases cathepsin B and L) and apilimod (endosomal trafficking inhibitor) potently decreased the amount of SARS-CoV-2 RNA in cell culture supernatants with minimal cytotoxicity. Surprisingly, we found that the macropinocytosis inhibitor ethylisopropylamiloride (EIPA) similarly decreased SARS-CoV-2 RNA levels in supernatants, suggesting that entry may additionally be mediated by an alternative pathway. HIV-1-specific inhibitors nevirapine (a nonnucleoside reverse transcriptase inhibitor [NNRTI]), amprenavir (a protease inhibitor), and allosteric integrase inhibitor 2 (ALLINI-2) modestly inhibited SARS-CoV-2 replication, albeit the 50% inhibitory concentration (IC50) values were much higher than that required for HIV-1. Taking the data together, this simplified assay will expedite basic SARS-CoV-2 research, be amenable to mid-throughput screening assays (i.e., drug, CRISPR, small interfering RNA [siRNA], etc.), and be applicable to a broad number of RNA and DNA viruses.IMPORTANCE Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of the coronavirus disease 2019 (COVID-19) pandemic, is continuing to cause immense respiratory disease and social and economic disruptions. Conventional assays that monitor SARS-CoV-2 growth in cell culture rely on costly and time-consuming RNA extraction procedures, hampering progress in basic SARS-CoV-2 research and development of effective therapeutics. Here, we developed a simple quantitative real-time PCR assay to monitor SARS-CoV-2 growth in cell culture supernatants that does not necessitate RNA extraction and that is as accurate and sensitive as existing methods. In a proof-of-concept screen, we found that E64D, apilimod, EIPA, and remdesivir can substantially impede SARS-Cov-2 replication, providing novel insight into viral entry and replication mechanisms. In addition, we show that this approach is easily adaptable to numerous other RNA and DNA viruses. This simplified assay will undoubtedly expedite basic SARS-CoV-2 and virology research and be amenable to use in drug screening platforms to identify therapeutics against SARS-CoV-2.


Subject(s)
Antiviral Agents/pharmacology , Betacoronavirus/drug effects , Betacoronavirus/growth & development , Cell Culture Techniques/methods , Coronavirus Infections/virology , Pneumonia, Viral/virology , Real-Time Polymerase Chain Reaction/methods , Betacoronavirus/genetics , Betacoronavirus/pathogenicity , COVID-19 , Pandemics , RNA, Viral/analysis , RNA, Viral/isolation & purification , SARS-CoV-2 , Virus Replication/drug effects
13.
Nat Immunol ; 21(11): 1327-1335, 2020 11.
Article in English | MEDLINE | ID: covidwho-728991

ABSTRACT

Although animal models have been evaluated for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, none have fully recapitulated the lung disease phenotypes seen in humans who have been hospitalized. Here, we evaluate transgenic mice expressing the human angiotensin I-converting enzyme 2 (ACE2) receptor driven by the cytokeratin-18 (K18) gene promoter (K18-hACE2) as a model of SARS-CoV-2 infection. Intranasal inoculation of SARS-CoV-2 in K18-hACE2 mice results in high levels of viral infection in lungs, with spread to other organs. A decline in pulmonary function occurs 4 days after peak viral titer and correlates with infiltration of monocytes, neutrophils and activated T cells. SARS-CoV-2-infected lung tissues show a massively upregulated innate immune response with signatures of nuclear factor-κB-dependent, type I and II interferon signaling, and leukocyte activation pathways. Thus, the K18-hACE2 model of SARS-CoV-2 infection shares many features of severe COVID-19 infection and can be used to define the basis of lung disease and test immune and antiviral-based countermeasures.


Subject(s)
Betacoronavirus/immunology , Coronavirus Infections/pathology , Immunity, Innate/immunology , Peptidyl-Dipeptidase A/genetics , Pneumonia, Viral/pathology , Pneumonia/pathology , Angiotensin-Converting Enzyme 2 , Animals , COVID-19 , Chlorocebus aethiops , Coronavirus Infections/immunology , Disease Models, Animal , Female , Humans , Interferon Type I/immunology , Interferon-gamma/immunology , Keratin-18/genetics , Leukocytes/immunology , Lymphocyte Activation/immunology , Male , Mice , Mice, Transgenic , Monocytes/immunology , NF-kappa B/immunology , Neutrophil Infiltration/immunology , Neutrophils/immunology , Pandemics , Pneumonia/genetics , Pneumonia/virology , Pneumonia, Viral/immunology , Promoter Regions, Genetic/genetics , SARS-CoV-2 , T-Lymphocytes/immunology , Vero Cells , Virus Replication/immunology
14.
Cell ; 183(1): 169-184.e13, 2020 10 01.
Article in English | MEDLINE | ID: covidwho-720448

ABSTRACT

The coronavirus disease 2019 pandemic has made deployment of an effective vaccine a global health priority. We evaluated the protective activity of a chimpanzee adenovirus-vectored vaccine encoding a prefusion stabilized spike protein (ChAd-SARS-CoV-2-S) in challenge studies with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and mice expressing the human angiotensin-converting enzyme 2 receptor. Intramuscular dosing of ChAd-SARS-CoV-2-S induces robust systemic humoral and cell-mediated immune responses and protects against lung infection, inflammation, and pathology but does not confer sterilizing immunity, as evidenced by detection of viral RNA and induction of anti-nucleoprotein antibodies after SARS-CoV-2 challenge. In contrast, a single intranasal dose of ChAd-SARS-CoV-2-S induces high levels of neutralizing antibodies, promotes systemic and mucosal immunoglobulin A (IgA) and T cell responses, and almost entirely prevents SARS-CoV-2 infection in both the upper and lower respiratory tracts. Intranasal administration of ChAd-SARS-CoV-2-S is a candidate for preventing SARS-CoV-2 infection and transmission and curtailing pandemic spread.


Subject(s)
Coronavirus Infections/immunology , Immunogenicity, Vaccine , Pneumonia, Viral/immunology , Viral Vaccines/immunology , Adenoviridae/genetics , Administration, Intranasal , Animals , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19 , COVID-19 Vaccines , Chlorocebus aethiops , Coronavirus Infections/pathology , Coronavirus Infections/prevention & control , Female , HEK293 Cells , Humans , Injections, Intramuscular , Mice , Mice, Inbred BALB C , Pandemics , Pneumonia, Viral/pathology , Respiratory Mucosa/immunology , Respiratory Mucosa/pathology , Respiratory Mucosa/virology , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Vero Cells , Viral Vaccines/administration & dosage
15.
Cell Host Microbe ; 28(3): 465-474.e4, 2020 09 09.
Article in English | MEDLINE | ID: covidwho-710174

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused millions of human infections, and an effective vaccine is critical to mitigate coronavirus-induced disease 2019 (COVID-19). Previously, we developed a replication-competent vesicular stomatitis virus (VSV) expressing a modified form of the SARS-CoV-2 spike gene in place of the native glycoprotein gene (VSV-eGFP-SARS-CoV-2). Here, we show that vaccination with VSV-eGFP-SARS-CoV-2 generates neutralizing immune responses and protects mice from SARS-CoV-2. Immunization of mice with VSV-eGFP-SARS-CoV-2 elicits high antibody titers that neutralize SARS-CoV-2 and target the receptor binding domain that engages human angiotensin-converting enzyme-2 (ACE2). Upon challenge with a human isolate of SARS-CoV-2, mice that expressed human ACE2 and were immunized with VSV-eGFP-SARS-CoV-2 show profoundly reduced viral infection and inflammation in the lung, indicating protection against pneumonia. Passive transfer of sera from VSV-eGFP-SARS-CoV-2-immunized animals also protects naive mice from SARS-CoV-2 challenge. These data support development of VSV-SARS-CoV-2 as an attenuated, replication-competent vaccine against SARS-CoV-2.


Subject(s)
Betacoronavirus , Coronavirus Infections/prevention & control , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Vesicular stomatitis Indiana virus/genetics , Viral Vaccines/genetics , Angiotensin-Converting Enzyme 2 , Animals , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , Betacoronavirus/immunology , Betacoronavirus/pathogenicity , COVID-19 , COVID-19 Vaccines , Chlorocebus aethiops , Coronavirus Infections/genetics , Coronavirus Infections/immunology , Coronavirus Infections/virology , Disease Models, Animal , Genetic Vectors , Green Fluorescent Proteins/genetics , Host Microbial Interactions/immunology , Humans , Lung/immunology , Lung/pathology , Lung/virology , Mice , Mice, Inbred BALB C , Mice, Transgenic , Peptidyl-Dipeptidase A/genetics , Pneumonia, Viral/immunology , Pneumonia, Viral/virology , Receptors, Virus/genetics , SARS-CoV-2 , Vaccines, Synthetic/genetics , Vaccines, Synthetic/immunology , Vaccines, Synthetic/pharmacology , Vero Cells , Vesicular stomatitis Indiana virus/immunology , Viral Vaccines/immunology , Viral Vaccines/pharmacology
16.
bioRxiv ; 2020 Jul 10.
Article in English | MEDLINE | ID: covidwho-663086

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused millions of human infections and hundreds of thousands of deaths. Accordingly, an effective vaccine is of critical importance in mitigating coronavirus induced disease 2019 (COVID-19) and curtailing the pandemic. We developed a replication-competent vesicular stomatitis virus (VSV)-based vaccine by introducing a modified form of the SARS-CoV-2 spike gene in place of the native glycoprotein gene (VSV-eGFP-SARS-CoV-2). Immunization of mice with VSV-eGFP-SARS-CoV-2 elicits high titers of antibodies that neutralize SARS-CoV-2 infection and target the receptor binding domain that engages human angiotensin converting enzyme-2 (ACE2). Upon challenge with a human isolate of SARS-CoV-2, mice expressing human ACE2 and immunized with VSV-eGFP-SARS-CoV-2 show profoundly reduced viral infection and inflammation in the lung indicating protection against pneumonia. Finally, passive transfer of sera from VSV-eGFP-SARS-CoV-2-immunized animals protects naïve mice from SARS-CoV-2 challenge. These data support development of VSV-eGFP-SARS-CoV-2 as an attenuated, replication-competent vaccine against SARS-CoV-2.

17.
bioRxiv ; 2020 Jul 10.
Article in English | MEDLINE | ID: covidwho-665969

ABSTRACT

Severe Acute Respiratory Syndrome Coronavirus -2 (SARS-CoV-2) emerged in late 2019 and has spread worldwide resulting in the Coronavirus Disease 2019 (COVID-19) pandemic. Although animal models have been evaluated for SARS-CoV-2 infection, none have recapitulated the severe lung disease phenotypes seen in hospitalized human cases. Here, we evaluate heterozygous transgenic mice expressing the human ACE2 receptor driven by the epithelial cell cytokeratin-18 gene promoter (K18-hACE2) as a model of SARS-CoV-2 infection. Intranasal inoculation of SARS-CoV-2 in K18-hACE2 mice results in high levels of viral infection in lung tissues with additional spread to other organs. Remarkably, a decline in pulmonary function, as measured by static and dynamic tests of respiratory capacity, occurs 4 days after peak viral titer and correlates with an inflammatory response marked by infiltration into the lung of monocytes, neutrophils, and activated T cells resulting in pneumonia. Cytokine profiling and RNA sequencing analysis of SARS-CoV-2-infected lung tissues show a massively upregulated innate immune response with prominent signatures of NF-kB-dependent, type I and II interferon signaling, and leukocyte activation pathways. Thus, the K18-hACE2 model of SARS-CoV-2 infection recapitulates many features of severe COVID-19 infection in humans and can be used to define the mechanistic basis of lung disease and test immune and antiviral-based countermeasures.

18.
Nature ; 584(7821): 443-449, 2020 08.
Article in English | MEDLINE | ID: covidwho-647154

ABSTRACT

The ongoing pandemic of coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a major threat to global health1 and the medical countermeasures available so far are limited2,3. Moreover, we currently lack a thorough understanding of the mechanisms of humoral immunity to SARS-CoV-24. Here we analyse a large panel of human monoclonal antibodies that target the spike (S) glycoprotein5, and identify several that exhibit potent neutralizing activity and fully block the receptor-binding domain of the S protein (SRBD) from interacting with human angiotensin-converting enzyme 2 (ACE2). Using competition-binding, structural and functional studies, we show that the monoclonal antibodies can be clustered into classes that recognize distinct epitopes on the SRBD, as well as distinct conformational states of the S trimer. Two potently neutralizing monoclonal antibodies, COV2-2196 and COV2-2130, which recognize non-overlapping sites, bound simultaneously to the S protein and neutralized wild-type SARS-CoV-2 virus in a synergistic manner. In two mouse models of SARS-CoV-2 infection, passive transfer of COV2-2196, COV2-2130 or a combination of both of these antibodies protected mice from weight loss and reduced the viral burden and levels of inflammation in the lungs. In addition, passive transfer of either of two of the most potent ACE2-blocking monoclonal antibodies (COV2-2196 or COV2-2381) as monotherapy protected rhesus macaques from SARS-CoV-2 infection. These results identify protective epitopes on the SRBD and provide a structure-based framework for rational vaccine design and the selection of robust immunotherapeutic agents.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Betacoronavirus/immunology , Coronavirus Infections/immunology , Coronavirus Infections/prevention & control , Pandemics/prevention & control , Pneumonia, Viral/immunology , Pneumonia, Viral/prevention & control , Angiotensin-Converting Enzyme 2 , Animals , Antibodies, Monoclonal/immunology , Betacoronavirus/chemistry , Binding, Competitive , COVID-19 , Cell Line , Cross Reactions , Disease Models, Animal , Epitopes, B-Lymphocyte/chemistry , Epitopes, B-Lymphocyte/immunology , Female , Humans , Macaca mulatta , Male , Mice , Middle Aged , Neutralization Tests , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Pre-Exposure Prophylaxis , SARS Virus/chemistry , SARS Virus/immunology , SARS-CoV-2 , Severe Acute Respiratory Syndrome/immunology , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism
19.
J Immunol ; 205(4): 915-922, 2020 08 15.
Article in English | MEDLINE | ID: covidwho-616100

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for millions of infections and hundreds of thousands of deaths globally. There are no widely available licensed therapeutics against SARS-CoV-2, highlighting an urgent need for effective interventions. The virus enters host cells through binding of a receptor-binding domain within its trimeric spike glycoprotein to human angiotensin-converting enzyme 2. In this article, we describe the generation and characterization of a panel of murine mAbs directed against the receptor-binding domain. One mAb, 2B04, neutralized wild-type SARS-CoV-2 in vitro with remarkable potency (half-maximal inhibitory concentration of <2 ng/ml). In a murine model of SARS-CoV-2 infection, 2B04 protected challenged animals from weight loss, reduced lung viral load, and blocked systemic dissemination. Thus, 2B04 is a promising candidate for an effective antiviral that can be used to prevent SARS-CoV-2 infection.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antibodies, Neutralizing/therapeutic use , Antibodies, Viral/therapeutic use , Betacoronavirus/drug effects , Coronavirus Infections/drug therapy , Coronavirus Infections/immunology , Pneumonia, Viral/drug therapy , Pneumonia, Viral/immunology , Angiotensin-Converting Enzyme 2 , Animals , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/pharmacology , Antibodies, Neutralizing/immunology , Antibodies, Neutralizing/pharmacology , Antibodies, Viral/immunology , Antibodies, Viral/pharmacology , COVID-19 , Chlorocebus aethiops , Coronavirus Infections/virology , Disease Models, Animal , Epitope Mapping , Female , HEK293 Cells , Humans , Immunodominant Epitopes/immunology , Mice , Mice, Inbred C57BL , Pandemics , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Pneumonia, Viral/virology , Protein Interaction Domains and Motifs/genetics , Protein Interaction Domains and Motifs/immunology , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism , Transfection , Vero Cells
20.
Cell ; 182(3): 744-753.e4, 2020 08 06.
Article in English | MEDLINE | ID: covidwho-592074

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a pandemic with millions of human infections. One limitation to the evaluation of potential therapies and vaccines to inhibit SARS-CoV-2 infection and ameliorate disease is the lack of susceptible small animals in large numbers. Commercially available laboratory strains of mice are not readily infected by SARS-CoV-2 because of species-specific differences in their angiotensin-converting enzyme 2 (ACE2) receptors. Here, we transduced replication-defective adenoviruses encoding human ACE2 via intranasal administration into BALB/c mice and established receptor expression in lung tissues. hACE2-transduced mice were productively infected with SARS-CoV-2, and this resulted in high viral titers in the lung, lung pathology, and weight loss. Passive transfer of a neutralizing monoclonal antibody reduced viral burden in the lung and mitigated inflammation and weight loss. The development of an accessible mouse model of SARS-CoV-2 infection and pathogenesis will expedite the testing and deployment of therapeutics and vaccines.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antibodies, Neutralizing/therapeutic use , Antibodies, Viral/therapeutic use , Betacoronavirus/immunology , Coronavirus Infections/therapy , Disease Models, Animal , Pneumonia, Viral/therapy , Angiotensin-Converting Enzyme 2 , Animals , COVID-19 , Chlorocebus aethiops , Coronavirus Infections/virology , Female , HEK293 Cells , Humans , Immunization, Passive/methods , Lung/metabolism , Lung/virology , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Inbred DBA , Mice, Knockout , Pandemics , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Pneumonia, Viral/virology , SARS-CoV-2 , Transduction, Genetic , Vero Cells , Viral Load/immunology
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