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1.
Cell Rep ; 38(6): 110348, 2022 02 08.
Article in English | MEDLINE | ID: covidwho-1712500

ABSTRACT

The increasing prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with the ability to escape existing humoral protection conferred by previous infection and/or immunization necessitates the discovery of broadly reactive neutralizing antibodies (nAbs). Utilizing mRNA display, we identify a set of antibodies against SARS-CoV-2 spike (S) proteins and characterize the structures of nAbs that recognize epitopes in the S1 subunit of the S glycoprotein. These structural studies reveal distinct binding modes for several antibodies, including the targeting of rare cryptic epitopes in the receptor-binding domain (RBD) of S that interact with angiotensin-converting enzyme 2 (ACE2) to initiate infection, as well as the S1 subdomain 1. Further, we engineer a potent ACE2-blocking nAb to sustain binding to S RBD with the E484K and L452R substitutions found in multiple SARS-CoV-2 variants. We demonstrate that mRNA display is an approach for the rapid identification of nAbs that can be used in combination to combat emerging SARS-CoV-2 variants.

2.
2021.
Preprint in English | Other preprints | ID: ppcovidwho-296014

ABSTRACT

ABSTRACT In response to the need for a safe, efficacious vaccine that elicits vigorous T cell as well as humoral protection against SARS-CoV-2 infection, we have developed a dual-antigen COVID-19 vaccine comprising both the viral spike (S) protein modified to increase cell-surface expression (S-Fusion) and nucleocapsid (N) protein with an Enhanced T-cell Stimulation Domain (N-ETSD) to enhance MHC class I and II presentation and T-cell responses. The antigens are delivered using a human adenovirus serotype 5 (hAd5) platform with E1, E2b, and E3 regions deleted that has been shown previously in cancer vaccine studies to be safe and effective in the presence of pre-existing hAd5 immunity. The findings reported here are focused on human T-cell responses due to the likelihood that such responses will sustain efficacy against emerging variants, a hypothesis supported by our in silico prediction of T-cell epitope HLA binding for both the first-wave SARS-CoV-2 ‘A’ strain and the B.1.351 strain K417N, E484K, and N501Y spike and T201I N variants. We demonstrate the hAd5 S-Fusion + N-ETSD vaccine antigens expressed by previously SARS-CoV-2-infected patient dendritic cells elicit Th1 dominant activation of autologous patient T cells, indicating the vaccine antigens have the potential to elicit immune responses in previously infected patients. For participants in our open-label Phase 1b study of the vaccine ( NCT04591717 ;https://clinicaltrials.gov/ct2/show/NCT04591717 ), the magnitude of Th-1 dominant S- and N-specific T-cell responses after a single prime subcutaneous injection were comparable to T-cell responses from previously infected patients. Furthermore, vaccinated participant T-cell responses to S were similar for A strain S and a series of spike variant peptides, including S variants in the B.1.1.7 and B.1.351 strains. The findings that this dual-antigen vaccine elicits SARS-CoV-2-relevant T-cell responses and that such cell-mediated protection is likely to be sustained against emerging variants supports the testing of this vaccine as a universal booster that would enhance and broaden existing immune protection conferred by currently approved S-based vaccines.

3.
Non-conventional in English | [Unspecified Source], Grey literature | ID: grc-750490

ABSTRACT

Initially, the global outbreak of COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spared children from severe disease. However, after the initial wave of infections, clusters of a novel hyperinflammatory disease have been reported in regions with ongoing SARS-CoV-2 epidemics. While the characteristic clinical features are becoming clear, the pathophysiology remains unknown. Herein, we report on the immune profiles of eight Multisystem Inflammatory Syndrome in Children (MIS-C) cases. We document that all MIS-C patients had evidence of prior SARS-CoV-2 exposure, mounting an antibody response with normal isotype-switching and neutralization capability. We further profiled the secreted immune response by high-dimensional cytokine assays, which identified elevated signatures of inflammation (IL-18 and IL-6), lymphocytic and myeloid chemotaxis and activation (CCL3, CCL4, and CDCP1) and mucosal immune dysregulation (IL-17A, CCL20, CCL28). Mass cytometry immunophenotyping of peripheral blood revealed reductions of mDC1 and non-classical monocytes, as well as both NK- and T- lymphocytes, suggesting extravasation to affected tissues. Markers of activated myeloid function were also evident, including upregulation of ICAM1 and FcR1 in neutrophil and non-classical monocytes, well-documented markers in autoinflammation and autoimmunity that indicate enhanced antigen presentation and Fc-mediated responses. Finally, to assess the role for autoimmunity secondary to infection, we profiled the auto-antigen reactivity of MIS-C plasma, which revealed both known disease-associated autoantibodies (anti-La) and novel candidates that recognize endothelial, gastrointestinal and immune-cell antigens. All patients were treated with anti- IL6R antibody or IVIG, which led to rapid disease resolution tracking with normalization of inflammatory markers.

4.
Cell Host Microbe ; 29(7): 1040-1042, 2021 07 14.
Article in English | MEDLINE | ID: covidwho-1309194

ABSTRACT

A previously immune-naive world population is experiencing natural infection with SARS-CoV-2. Severe COVID-19 predominantly impacts adults, yet multisystem inflammatory disorder primarily impacts children. Herein, we discuss known clinical and biological features of SARS-CoV-2 in children and reflect on currently identified immune features and discuss what remains unknown.


Subject(s)
COVID-19/immunology , COVID-19/physiopathology , Child , Hospitalization , Humans , Immunity , SARS-CoV-2 , Vaccination
5.
Sci Rep ; 11(1): 12740, 2021 06 17.
Article in English | MEDLINE | ID: covidwho-1275953

ABSTRACT

The SARS-CoV-2 variants replacing the first wave strain pose an increased threat by their potential ability to escape pre-existing humoral protection. An angiotensin converting enzyme 2 (ACE2) decoy that competes with endogenous ACE2 for binding of the SARS-CoV-2 spike receptor binding domain (S RBD) and inhibits infection may offer a therapeutic option with sustained efficacy against variants. Here, we used Molecular Dynamics (MD) simulation to predict ACE2 sequence substitutions that might increase its affinity for S RBD and screened candidate ACE2 decoys in vitro. The lead ACE2(T27Y/H34A)-IgG1FC fusion protein with enhanced S RBD affinity shows greater live SARS-CoV-2 virus neutralization capability than wild type ACE2. MD simulation was used to predict the effects of S RBD variant mutations on decoy affinity that was then confirmed by testing of an ACE2 Triple Decoy that included an additional enzyme activity-deactivating H374N substitution against mutated S RBD. The ACE2 Triple Decoy maintains high affinity for mutated S RBD, displays enhanced affinity for S RBD N501Y or L452R, and has the highest affinity for S RBD with both E484K and N501Y mutations, making it a viable therapeutic option for the prevention or treatment of SARS-CoV-2 infection with a high likelihood of efficacy against variants.


Subject(s)
Amino Acid Substitution , Angiotensin-Converting Enzyme 2/chemistry , Angiotensin-Converting Enzyme 2/metabolism , Antiviral Agents/pharmacology , COVID-19/metabolism , Drug Discovery/methods , Molecular Dynamics Simulation , SARS-CoV-2/metabolism , Signal Transduction/drug effects , Amino Acid Sequence , COVID-19/virology , Humans , Mutation , Protein Binding/drug effects , Protein Domains/genetics , Spike Glycoprotein, Coronavirus/metabolism , Virus Internalization/drug effects
6.
J Clin Immunol ; 41(7): 1457-1462, 2021 10.
Article in English | MEDLINE | ID: covidwho-1252168

ABSTRACT

While adults with Down syndrome (DS) are at increased risk of severe COVID-19 pneumonia, little is known about COVID-19 in children with DS. In children without DS, SARS-CoV-2 can rarely cause severe COVID-19 pneumonia, or an even rarer and more typically pediatric condition, multisystem inflammatory syndrome in children (MIS-C). Although the underlying mechanisms are still unknown, MIS-C is thought to be primarily immune-mediated. Here, we describe an atypical, severe form of MIS-C in two infant girls with DS who were hospitalized for over 4 months. Immunological evaluation revealed pronounced neutrophilia, B cell depletion, increased circulating IL-6 and IL-8, and elevated markers of immune activation ICAM1 and FcÉ£RI. Importantly, uninfected children with DS presented with similar but less stark immune features at steady state, possibly explaining risk of further uncontrolled inflammation following SARS-CoV-2 infection. Overall, a severe, atypical form of MIS-C may occur in children with DS.


Subject(s)
COVID-19/diagnosis , Down Syndrome/diagnosis , SARS-CoV-2/physiology , Systemic Inflammatory Response Syndrome/diagnosis , COVID-19/complications , Down Syndrome/complications , Fatal Outcome , Female , Hospitalization , Humans , Infant , Syndrome
8.
J Exp Med ; 218(6)2021 06 07.
Article in English | MEDLINE | ID: covidwho-1203555

ABSTRACT

Multisystem inflammatory syndrome in children (MIS-C) emerged in April 2020 in communities with high COVID-19 rates. This new condition is heterogenous but resembles Kawasaki disease (KD), a well-known but poorly understood and clinically heterogenous pediatric inflammatory condition for which weak associations have been found with a myriad of viral illnesses. Epidemiological data clearly indicate that SARS-CoV-2 is the trigger for MIS-C, which typically occurs about 1 mo after infection. These findings support the hypothesis of viral triggers for the various forms of classic KD. We further suggest that rare inborn errors of immunity (IEIs) altering the immune response to SARS-CoV-2 may underlie the pathogenesis of MIS-C in some children. The discovery of monogenic IEIs underlying MIS-C would shed light on its pathogenesis, paving the way for a new genetic approach to classic KD, revisited as a heterogeneous collection of IEIs to viruses.


Subject(s)
COVID-19/etiology , Mucocutaneous Lymph Node Syndrome/genetics , Mucocutaneous Lymph Node Syndrome/virology , SARS-CoV-2/pathogenicity , Systemic Inflammatory Response Syndrome/etiology , Biomarkers/blood , COVID-19/epidemiology , COVID-19/immunology , Child , Cytokines/blood , Genetic Predisposition to Disease , Genome-Wide Association Study , Humans , Inflammation/etiology , Inflammation/genetics , Inflammation/immunology , Inflammation Mediators/blood , Lymphohistiocytosis, Hemophagocytic/genetics , Lymphohistiocytosis, Hemophagocytic/virology , Models, Biological , Mucocutaneous Lymph Node Syndrome/epidemiology , Pandemics , SARS-CoV-2/immunology , Systemic Inflammatory Response Syndrome/epidemiology , Systemic Inflammatory Response Syndrome/immunology
9.
Genet Med ; 23(3): 576-580, 2021 03.
Article in English | MEDLINE | ID: covidwho-872688

ABSTRACT

PURPOSE: Rare genetic conditions like Down syndrome (DS) are historically understudied. Infection is a leading cause of mortality in DS, along with cardiac anomalies. Currently, it is unknown how the COVID-19 pandemic affects individuals with DS. Herein, we report an analysis of individuals with DS who were hospitalized with COVID-19 in New York, New York, USA. METHODS: In this retrospective, dual-center study of 7246 patients hospitalized with COVID-19, we analyzed all patients with DS admitted in the Mount Sinai Health System and Columbia University Irving Medical Center. We assessed hospitalization rates, clinical characteristics, and outcomes. RESULTS: We identified 12 patients with DS. Hospitalized individuals with DS are on average ten years younger than patients without DS. Patients with DS have more severe disease than controls, particularly an increased incidence of sepsis and mechanical ventilation. CONCLUSION: We demonstrate that individuals with DS who are hospitalized with COVID-19 are younger than their non-DS counterparts, and that they have more severe disease than age-matched controls. We conclude that particular care should be considered for both the prevention and treatment of COVID-19 in these patients.


Subject(s)
COVID-19/pathology , Down Syndrome , Adult , Comorbidity , Down Syndrome/complications , Female , Hospitalization , Humans , Male , Middle Aged , New York/epidemiology , Pandemics , Retrospective Studies
10.
Immunity ; 53(3): 672-684.e11, 2020 09 15.
Article in English | MEDLINE | ID: covidwho-797268

ABSTRACT

Autoinflammatory disease can result from monogenic errors of immunity. We describe a patient with early-onset multi-organ immune dysregulation resulting from a mosaic, gain-of-function mutation (S703I) in JAK1, encoding a kinase essential for signaling downstream of >25 cytokines. By custom single-cell RNA sequencing, we examine mosaicism with single-cell resolution. We find that JAK1 transcription was predominantly restricted to a single allele across different cells, introducing the concept of a mutational "transcriptotype" that differs from the genotype. Functionally, the mutation increases JAK1 activity and transactivates partnering JAKs, independent of its catalytic domain. S703I JAK1 is not only hypermorphic for cytokine signaling but also neomorphic, as it enables signaling cascades not canonically mediated by JAK1. Given these results, the patient was treated with tofacitinib, a JAK inhibitor, leading to the rapid resolution of clinical disease. These findings offer a platform for personalized medicine with the concurrent discovery of fundamental biological principles.


Subject(s)
Hereditary Autoinflammatory Diseases/genetics , Hereditary Autoinflammatory Diseases/pathology , Janus Kinase 1/genetics , Systemic Inflammatory Response Syndrome/genetics , Systemic Inflammatory Response Syndrome/pathology , Adolescent , COVID-19/mortality , Catalytic Domain/genetics , Cell Line , Cytokines/metabolism , Female , Gain of Function Mutation/genetics , Genotype , HEK293 Cells , Hereditary Autoinflammatory Diseases/drug therapy , Humans , Janus Kinase 1/antagonists & inhibitors , Mosaicism , Piperidines/therapeutic use , Precision Medicine/methods , Pyrimidines/therapeutic use , Signal Transduction/immunology , Systemic Inflammatory Response Syndrome/drug therapy
11.
Cell ; 183(4): 982-995.e14, 2020 11 12.
Article in English | MEDLINE | ID: covidwho-756809

ABSTRACT

Initially, children were thought to be spared from disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, a month into the epidemic, a novel multisystem inflammatory syndrome in children (MIS-C) emerged. Herein, we report on the immune profiles of nine MIS-C cases. All MIS-C patients had evidence of prior SARS-CoV-2 exposure, mounting an antibody response with intact neutralization capability. Cytokine profiling identified elevated signatures of inflammation (IL-18 and IL-6), lymphocytic and myeloid chemotaxis and activation (CCL3, CCL4, and CDCP1), and mucosal immune dysregulation (IL-17A, CCL20, and CCL28). Immunophenotyping of peripheral blood revealed reductions of non-classical monocytes, and subsets of NK and T lymphocytes, suggesting extravasation to affected tissues. Finally, profiling the autoantigen reactivity of MIS-C plasma revealed both known disease-associated autoantibodies (anti-La) and novel candidates that recognize endothelial, gastrointestinal, and immune-cell antigens. All patients were treated with anti-IL-6R antibody and/or IVIG, which led to rapid disease resolution.


Subject(s)
Inflammation/pathology , Systemic Inflammatory Response Syndrome/pathology , Adolescent , Antibodies, Viral/blood , Autoantibodies/blood , Betacoronavirus/immunology , Betacoronavirus/isolation & purification , COVID-19 , Chemokine CCL3/metabolism , Child , Child, Preschool , Coronavirus Infections/complications , Coronavirus Infections/pathology , Coronavirus Infections/virology , Female , Humans , Immunity, Humoral , Infant , Infant, Newborn , Inflammation/metabolism , Interleukin-17/metabolism , Interleukin-18/metabolism , Killer Cells, Natural/cytology , Killer Cells, Natural/metabolism , Male , Pandemics , Pneumonia, Viral/complications , Pneumonia, Viral/pathology , Pneumonia, Viral/virology , SARS-CoV-2 , Systemic Inflammatory Response Syndrome/immunology , Systemic Inflammatory Response Syndrome/metabolism , T-Lymphocytes/cytology , T-Lymphocytes/metabolism , Young Adult
13.
medRxiv ; 2020 Jul 06.
Article in English | MEDLINE | ID: covidwho-663795

ABSTRACT

Initially, the global outbreak of COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spared children from severe disease. However, after the initial wave of infections, clusters of a novel hyperinflammatory disease have been reported in regions with ongoing SARS-CoV-2 epidemics. While the characteristic clinical features are becoming clear, the pathophysiology remains unknown. Herein, we report on the immune profiles of eight Multisystem Inflammatory Syndrome in Children (MIS-C) cases. We document that all MIS-C patients had evidence of prior SARS-CoV-2 exposure, mounting an antibody response with normal isotype-switching and neutralization capability. We further profiled the secreted immune response by high-dimensional cytokine assays, which identified elevated signatures of inflammation (IL-18 and IL-6), lymphocytic and myeloid chemotaxis and activation (CCL3, CCL4, and CDCP1) and mucosal immune dysregulation (IL-17A, CCL20, CCL28). Mass cytometry immunophenotyping of peripheral blood revealed reductions of mDC1 and non-classical monocytes, as well as both NK- and T- lymphocytes, suggesting extravasation to affected tissues. Markers of activated myeloid function were also evident, including upregulation of ICAM1 and FcR1 in neutrophil and non-classical monocytes, well-documented markers in autoinflammation and autoimmunity that indicate enhanced antigen presentation and Fc-mediated responses. Finally, to assess the role for autoimmunity secondary to infection, we profiled the auto-antigen reactivity of MIS-C plasma, which revealed both known disease-associated autoantibodies (anti-La) and novel candidates that recognize endothelial, gastrointestinal and immune-cell antigens. All patients were treated with anti- IL6R antibody or IVIG, which led to rapid disease resolution tracking with normalization of inflammatory markers.

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