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1.
Proc Biol Sci ; 289(1979): 20220193, 2022 07 27.
Article in English | MEDLINE | ID: covidwho-1961305

ABSTRACT

Pandemics originating from non-human animals highlight the need to understand how natural hosts have evolved in response to emerging human pathogens and which groups may be susceptible to infection and/or potential reservoirs to mitigate public health and conservation concerns. Multiple zoonotic coronaviruses, such as severe acute respiratory syndrome-associated coronavirus (SARS-CoV), SARS-CoV-2 and Middle Eastern respiratory syndrome-associated coronavirus (MERS-CoV), are hypothesized to have evolved in bats. We investigate angiotensin-converting enzyme 2 (ACE2), the host protein bound by SARS-CoV and SARS-CoV-2, and dipeptidyl-peptidase 4 (DPP4 or CD26), the host protein bound by MERS-CoV, in the largest bat datasets to date. Both the ACE2 and DPP4 genes are under strong selection pressure in bats, more so than in other mammals, and in residues that contact viruses. Additionally, mammalian groups vary in their similarity to humans in residues that contact SARS-CoV, SARS-CoV-2 and MERS-CoV, and increased similarity to humans in binding residues is broadly predictive of susceptibility to SARS-CoV-2. This work augments our understanding of the relationship between coronaviruses and mammals, particularly bats, provides taxonomically diverse data for studies of how host proteins are bound by coronaviruses and can inform surveillance, conservation and public health efforts.


Subject(s)
Chiroptera , Middle East Respiratory Syndrome Coronavirus , Receptors, Coronavirus , SARS Virus , SARS-CoV-2 , Angiotensin-Converting Enzyme 2 , Animals , COVID-19 , Chiroptera/genetics , Dipeptidyl Peptidase 4/genetics , Dipeptidyl Peptidase 4/metabolism , Humans , Middle East Respiratory Syndrome Coronavirus/metabolism , SARS Virus/metabolism , SARS-CoV-2/metabolism
2.
JCI Insight ; 7(13)2022 07 08.
Article in English | MEDLINE | ID: covidwho-1932894

ABSTRACT

BACKGROUNDProlonged symptoms after SARS-CoV-2 infection are well documented. However, which factors influence development of long-term symptoms, how symptoms vary across ethnic groups, and whether long-term symptoms correlate with biomarkers are points that remain elusive.METHODSAdult SARS-CoV-2 reverse transcription PCR-positive (RT-PCR-positive) patients were recruited at Stanford from March 2020 to February 2021. Study participants were seen for in-person visits at diagnosis and every 1-3 months for up to 1 year after diagnosis; they completed symptom surveys and underwent blood draws and nasal swab collections at each visit.RESULTSOur cohort (n = 617) ranged from asymptomatic to critical COVID-19 infections. In total, 40% of participants reported at least 1 symptom associated with COVID-19 six months after diagnosis. Median time from diagnosis to first resolution of all symptoms was 44 days; median time from diagnosis to sustained symptom resolution with no recurring symptoms for 1 month or longer was 214 days. Anti-nucleocapsid IgG level in the first week after positive RT-PCR test and history of lung disease were associated with time to sustained symptom resolution. COVID-19 disease severity, ethnicity, age, sex, and remdesivir use did not affect time to sustained symptom resolution.CONCLUSIONWe found that all disease severities had a similar risk of developing post-COVID-19 syndrome in an ethnically diverse population. Comorbid lung disease and lower levels of initial IgG response to SARS-CoV-2 nucleocapsid antigen were associated with longer symptom duration.TRIAL REGISTRATIONClinicalTrials.gov, NCT04373148.FUNDINGNIH UL1TR003142 CTSA grant, NIH U54CA260517 grant, NIEHS R21 ES03304901, Sean N Parker Center for Allergy and Asthma Research at Stanford University, Chan Zuckerberg Biohub, Chan Zuckerberg Initiative, Sunshine Foundation, Crown Foundation, and Parker Foundation.


Subject(s)
COVID-19 , COVID-19/complications , Humans , Immunoglobulin G , SARS-CoV-2
3.
J Neuropathol Exp Neurol ; 81(9): 666-695, 2022 08 16.
Article in English | MEDLINE | ID: covidwho-1931851

ABSTRACT

Brains of 42 COVID-19 decedents and 107 non-COVID-19 controls were studied. RT-PCR screening of 16 regions from 20 COVID-19 autopsies found SARS-CoV-2 E gene viral sequences in 7 regions (2.5% of 320 samples), concentrated in 4/20 subjects (20%). Additional screening of olfactory bulb (OB), amygdala (AMY) and entorhinal area for E, N1, N2, RNA-dependent RNA polymerase, and S gene sequences detected one or more of these in OB in 8/21 subjects (38%). It is uncertain whether these RNA sequences represent viable virus. Significant histopathology was limited to 2/42 cases (4.8%), one with a large acute cerebral infarct and one with hemorrhagic encephalitis. Case-control RNAseq in OB and AMY found more than 5000 and 700 differentially expressed genes, respectively, unrelated to RT-PCR results; these involved immune response, neuronal constituents, and olfactory/taste receptor genes. Olfactory marker protein-1 reduction indicated COVID-19-related loss of OB olfactory mucosa afferents. Iba-1-immunoreactive microglia had reduced area fractions in cerebellar cortex and AMY, and cytokine arrays showed generalized downregulation in AMY and upregulation in blood serum in COVID-19 cases. Although OB is a major brain portal for SARS-CoV-2, COVID-19 brain changes are more likely due to blood-borne immune mediators and trans-synaptic gene expression changes arising from OB deafferentation.


Subject(s)
COVID-19 , SARS-CoV-2 , Brain , Gene Expression , Humans , Immunity
4.
Cell Rep Med ; 3(7): 100680, 2022 07 19.
Article in English | MEDLINE | ID: covidwho-1907870

ABSTRACT

The biological determinants underlying the range of coronavirus 2019 (COVID-19) clinical manifestations are not fully understood. Here, over 1,400 plasma proteins and 2,600 single-cell immune features comprising cell phenotype, endogenous signaling activity, and signaling responses to inflammatory ligands are cross-sectionally assessed in peripheral blood from 97 patients with mild, moderate, and severe COVID-19 and 40 uninfected patients. Using an integrated computational approach to analyze the combined plasma and single-cell proteomic data, we identify and independently validate a multi-variate model classifying COVID-19 severity (multi-class area under the curve [AUC]training = 0.799, p = 4.2e-6; multi-class AUCvalidation = 0.773, p = 7.7e-6). Examination of informative model features reveals biological signatures of COVID-19 severity, including the dysregulation of JAK/STAT, MAPK/mTOR, and nuclear factor κB (NF-κB) immune signaling networks in addition to recapitulating known hallmarks of COVID-19. These results provide a set of early determinants of COVID-19 severity that may point to therapeutic targets for prevention and/or treatment of COVID-19 progression.


Subject(s)
COVID-19 , Humans , NF-kappa B/metabolism , Proteomics , SARS-CoV-2 , Signal Transduction
5.
J Clin Virol ; 153: 105217, 2022 08.
Article in English | MEDLINE | ID: covidwho-1885897

ABSTRACT

BACKGROUND: Humoral and cellular immune responses to SARS-CoV-2 vaccination among immunosuppressed patients remain poorly defined, as well as variables associated with poor response. METHODS: We performed a retrospective observational cohort study at a large Northern California healthcare system of infection-naïve individuals fully vaccinated against SARS-CoV-2 (mRNA-1273, BNT162b2, or Ad26.COV2.S) with clinical SARS-CoV-2 interferon gamma release assay (IGRA) ordered between January through November 2021. Humoral and cellular immune responses were measured by anti-SARS-CoV-2 S1 IgG ELISA (anti-S1 IgG) and IGRA, respectively, following primary and/or booster vaccination. RESULTS: 496 immunosuppressed patients (54% female; median age 50 years) were included. 62% (261/419) of patients had positive anti-S1 IgG and 71% (277/389) had positive IGRA after primary vaccination, with 20% of patients having a positive IGRA only. Following booster, 69% (81/118) had positive anti-S1 IgG and 73% (91/124) had positive IGRA. Factors associated with low humoral response rates after primary vaccination included anti-CD20 monoclonal antibodies (P < 0.001), sphingosine 1-phsophate (S1P) receptor modulators (P < 0.001), mycophenolate (P = 0.002), and B cell lymphoma (P = 0.004); those associated with low cellular response rates included S1P receptor modulators (P < 0.001) and mycophenolate (P < 0.001). Of patients who had poor humoral response to primary vaccination, 35% (18/52) developed a significantly higher response after the booster. Only 5% (2/42) of patients developed a significantly higher cellular response to the booster dose compared to primary vaccination. CONCLUSIONS: Humoral and cellular response rates to primary and booster SARS-CoV-2 vaccination differ among immunosuppressed patient groups. Clinical testing of cellular immunity is important in monitoring vaccine response in vulnerable populations.


Subject(s)
COVID-19 , Viral Vaccines , Ad26COVS1 , Antibodies, Viral , BNT162 Vaccine , COVID-19/prevention & control , COVID-19 Vaccines , Female , Humans , Immunity, Humoral , Immunoglobulin G , Male , Middle Aged , Retrospective Studies , SARS-CoV-2 , Vaccination
7.
Sci Transl Med ; 14(634): eabn7842, 2022 03 02.
Article in English | MEDLINE | ID: covidwho-1723505

ABSTRACT

Multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants that have mutations associated with increased transmission and antibody escape have arisen over the course of the current pandemic. Although the current vaccines have largely been effective against past variants, the number of mutations found on the Omicron (B.1.1.529) spike protein appear to diminish the protection conferred by preexisting immunity. Using vesicular stomatitis virus (VSV) pseudoparticles expressing the spike protein of several SARS-CoV-2 variants, we evaluated the magnitude and breadth of the neutralizing antibody response over time in individuals after infection and in mRNA-vaccinated individuals. We observed that boosting increases the magnitude of the antibody response to wild-type (D614), Beta, Delta, and Omicron variants; however, the Omicron variant was the most resistant to neutralization. We further observed that vaccinated healthy adults had robust and broad antibody responses, whereas responses may have been reduced in vaccinated pregnant women, underscoring the importance of learning how to maximize mRNA vaccine responses in pregnant populations. Findings from this study show substantial heterogeneity in the magnitude and breadth of responses after infection and mRNA vaccination and may support the addition of more conserved viral antigens to existing SARS-CoV-2 vaccines.


Subject(s)
Antibodies, Neutralizing , Antibodies, Viral , COVID-19 , Adult , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/immunology , COVID-19/prevention & control , COVID-19/virology , COVID-19 Vaccines/immunology , Female , Humans , Pregnancy , Pregnancy Complications, Infectious/immunology , Pregnancy Complications, Infectious/prevention & control , Pregnancy Complications, Infectious/virology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Vaccines, Synthetic/immunology , mRNA Vaccines/immunology
8.
Cell ; 185(6): 1025-1040.e14, 2022 03 17.
Article in English | MEDLINE | ID: covidwho-1649487

ABSTRACT

During the SARS-CoV-2 pandemic, novel and traditional vaccine strategies have been deployed globally. We investigated whether antibodies stimulated by mRNA vaccination (BNT162b2), including third-dose boosting, differ from those generated by infection or adenoviral (ChAdOx1-S and Gam-COVID-Vac) or inactivated viral (BBIBP-CorV) vaccines. We analyzed human lymph nodes after infection or mRNA vaccination for correlates of serological differences. Antibody breadth against viral variants is lower after infection compared with all vaccines evaluated but improves over several months. Viral variant infection elicits variant-specific antibodies, but prior mRNA vaccination imprints serological responses toward Wuhan-Hu-1 rather than variant antigens. In contrast to disrupted germinal centers (GCs) in lymph nodes during infection, mRNA vaccination stimulates robust GCs containing vaccine mRNA and spike antigen up to 8 weeks postvaccination in some cases. SARS-CoV-2 antibody specificity, breadth, and maturation are affected by imprinting from exposure history and distinct histological and antigenic contexts in infection compared with vaccination.


Subject(s)
Antibodies, Viral , BNT162 Vaccine , COVID-19 , Germinal Center , Antigens, Viral , COVID-19/prevention & control , Humans , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus , Vaccination
10.
Sci Transl Med ; 14(635): eabm7853, 2022 03 09.
Article in English | MEDLINE | ID: covidwho-1630954

ABSTRACT

A damaging inflammatory response is implicated in the pathogenesis of severe coronavirus disease 2019 (COVID-19), but mechanisms contributing to this response are unclear. In two prospective cohorts, early non-neutralizing, afucosylated immunoglobulin G (IgG) antibodies specific to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were associated with progression from mild to more severe COVID-19. To study the biology of afucosylated IgG immune complexes, we developed an in vivo model that revealed that human IgG-Fc-gamma receptor (FcγR) interactions could regulate inflammation in the lung. Afucosylated IgG immune complexes isolated from patients with COVID-19 induced inflammatory cytokine production and robust infiltration of the lung by immune cells. In contrast to the antibody structures that were associated with disease progression, antibodies that were elicited by messenger RNA SARS-CoV-2 vaccines were highly fucosylated and enriched in sialylation, both modifications that reduce the inflammatory potential of IgG. Vaccine-elicited IgG did not promote an inflammatory lung response. These results show that human IgG-FcγR interactions regulate inflammation in the lung and define distinct lung activities mediated by the IgG that are associated with protection against, or progression to, severe COVID-19.


Subject(s)
COVID-19 , Antibodies, Neutralizing , Antibodies, Viral , Antibody Formation , COVID-19 Vaccines , Humans , Prospective Studies , SARS-CoV-2 , Spike Glycoprotein, Coronavirus
12.
Cell Mol Immunol ; 19(2): 222-233, 2022 02.
Article in English | MEDLINE | ID: covidwho-1607212

ABSTRACT

Although antivirals are important tools to control severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, effective vaccines are essential to control the current coronavirus disease 2019 (COVID-19) pandemic. Plant-derived virus-like particle (VLP) vaccine candidates have previously demonstrated immunogenicity and efficacy against influenza. Here, we report the immunogenicity and protection induced in rhesus macaques by intramuscular injections of a VLP bearing a SARS-CoV-2 spike protein (CoVLP) vaccine candidate formulated with or without Adjuvant System 03 (AS03) or cytidine-phospho-guanosine (CpG) 1018. Although a single dose of the unadjuvanted CoVLP vaccine candidate stimulated humoral and cell-mediated immune responses, booster immunization (at 28 days after priming) and adjuvant administration significantly improved both responses, with higher immunogenicity and protection provided by the AS03-adjuvanted CoVLP. Fifteen micrograms of CoVLP adjuvanted with AS03 induced a polyfunctional interleukin-2 (IL-2)-driven response and IL-4 expression in CD4 T cells. Animals were challenged by multiple routes (i.e., intratracheal, intranasal, and ocular) with a total viral dose of 106 plaque-forming units of SARS-CoV-2. Lower viral replication in nasal swabs and bronchoalveolar lavage fluid (BALF) as well as fewer SARS-CoV-2-infected cells and immune cell infiltrates in the lungs concomitant with reduced levels of proinflammatory cytokines and chemotactic factors in the BALF were observed in animals immunized with the CoVLP adjuvanted with AS03. No clinical, pathologic, or virologic evidence of vaccine-associated enhanced disease was observed in vaccinated animals. The CoVLP adjuvanted with AS03 was therefore selected for vaccine development and clinical trials.


Subject(s)
Adjuvants, Immunologic/adverse effects , COVID-19 Vaccines/adverse effects , COVID-19/immunology , COVID-19/prevention & control , Immunogenicity, Vaccine/immunology , Pandemics/prevention & control , Polysorbates/adverse effects , SARS-CoV-2/immunology , Squalene/adverse effects , Tobacco/metabolism , Vaccination/methods , Vaccines, Virus-Like Particle/adverse effects , alpha-Tocopherol/adverse effects , Adjuvants, Immunologic/administration & dosage , Animals , Antibodies, Neutralizing/blood , Antibodies, Neutralizing/immunology , Antibodies, Viral/blood , Antibodies, Viral/immunology , COVID-19/epidemiology , COVID-19/virology , COVID-19 Vaccines/administration & dosage , Disease Models, Animal , Drug Combinations , Drug Compounding/methods , Immunity, Humoral , Macaca mulatta , Male , Polysorbates/administration & dosage , Recombinant Proteins/immunology , Recombinant Proteins/metabolism , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , Squalene/administration & dosage , Treatment Outcome , Vaccines, Virus-Like Particle/administration & dosage , alpha-Tocopherol/administration & dosage
13.
Cell Host Microbe ; 29(12): 1738-1743.e4, 2021 12 08.
Article in English | MEDLINE | ID: covidwho-1574127

ABSTRACT

Different SARS-CoV-2 vaccines are approved in various countries, but few direct comparisons of the antibody responses they stimulate have been reported. We collected plasma specimens in July 2021 from 196 Mongolian participants fully vaccinated with one of four COVID-19 vaccines: Pfizer/BioNTech, AstraZeneca, Sputnik V, and Sinopharm. Functional antibody testing with a panel of nine SARS-CoV-2 viral variant receptor binding domain (RBD) proteins revealed marked differences in vaccine responses, with low antibody levels and RBD-ACE2 blocking activity stimulated by the Sinopharm and Sputnik V vaccines in comparison to the AstraZeneca or Pfizer/BioNTech vaccines. The Alpha variant caused 97% of infections in Mongolia in June and early July 2021. Individuals who recover from SARS-CoV-2 infection after vaccination achieve high antibody titers in most cases. These data suggest that public health interventions such as vaccine boosting, potentially with more potent vaccine types, may be needed to control COVID-19 in Mongolia and worldwide.


Subject(s)
Antibodies, Viral/blood , COVID-19 Vaccines/administration & dosage , COVID-19/prevention & control , Mass Vaccination , SARS-CoV-2/drug effects , Adult , Aged , Angiotensin-Converting Enzyme 2/antagonists & inhibitors , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/immunology , Antibodies, Viral/biosynthesis , COVID-19/epidemiology , COVID-19/immunology , COVID-19/virology , Female , Gene Expression , Humans , Immune Sera/chemistry , Immunogenicity, Vaccine , Male , Middle Aged , Mongolia/epidemiology , Retrospective Studies , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity
14.
Non-conventional in English | [Unspecified Source], Grey literature | ID: grc-750507

ABSTRACT

During virus infection B cells are critical for the production of antibodies and protective immunity. Here we show that the human B cell compartment in patients with diagnostically confirmed SARS-CoV-2 and clinical COVID-19 is rapidly altered with the early recruitment of B cells expressing a limited subset of IGHV genes, progressing to a highly polyclonal response of B cells with broader IGHV gene usage and extensive class switching to IgG and IgA subclasses with limited somatic hypermutation in the initial weeks of infection. We identify extensive convergence of antibody sequences across SARS-CoV-2 patients, highlighting stereotyped naive responses to this virus. Notably, sequence-based detection in COVID-19 patients of convergent B cell clonotypes previously reported in SARS-CoV infection predicts the presence of SARS-CoV/SARS-CoV-2 cross-reactive antibody titers specific for the receptor-binding domain. These findings offer molecular insights into shared features of human B cell responses to SARS-CoV-2 and other zoonotic spillover coronaviruses.

15.
Ann Intern Med ; 174(8): 1073-1080, 2021 08.
Article in English | MEDLINE | ID: covidwho-1456490

ABSTRACT

BACKGROUND: Assessing the evolution of SARS-CoV-2 immune response among patients receiving dialysis can define its durability in a highly clinically relevant context because patients receiving dialysis share the characteristics of persons most susceptible to SARS-CoV-2 infection. OBJECTIVE: To evaluate the persistence of SARS-CoV-2 receptor-binding domain (RBD) IgG in seroprevalent patients receiving dialysis. DESIGN: Prospective. SETTING: Nationwide sample from dialysis facilities. PATIENTS: 2215 patients receiving dialysis who had evidence of SARS-CoV-2 infection as of July 2020. MEASUREMENTS: Remainder plasma from routine monthly laboratories was used to measure semiquantitative RBD IgG index value over 6 months. RESULTS: A total of 2063 (93%) seroprevalent patients reached an assay detectable response (IgG index value ≥1). Most (n = 1323, 60%) had responses in July with index values classified as high (IgG ≥10); 1003 (76%) remained within this stratum. Adjusted median index values declined slowly but continuously (July vs. December values were 21 vs. 13; P < 0.001). The trajectory of the response did not vary by age group, sex, race/ethnicity, or diabetes status. Patients without an assay detectable response (n = 137) were more likely to be White and in the younger (18 to 44 years) or older (≥80 years) age groups and less likely to have diabetes and hypoalbuminemia. LIMITATION: Lack of data on symptoms or reverse transcriptase polymerase chain reaction diagnosis, cohort of persons who survived infection, and use of a semiquantitative assay. CONCLUSION: Despite impaired immunity, most seropositive patients receiving dialysis maintained RBD antibody levels over 6 months. A slow and continual decline in median antibody levels over time was seen, but no indication that subgroups with impaired immunity had a shorter-lived humoral response was found. PRIMARY FUNDING SOURCE: Ascend Clinical Laboratories.


Subject(s)
Antibodies, Viral/blood , COVID-19/immunology , Immunoglobulin G/blood , Protein Domains/immunology , Renal Dialysis , Spike Glycoprotein, Coronavirus/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Neutralizing/immunology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prospective Studies , SARS-CoV-2 , Young Adult
16.
Clin Chem ; 68(1): 204-213, 2021 12 30.
Article in English | MEDLINE | ID: covidwho-1450383

ABSTRACT

BACKGROUND: Detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid antigen in blood has been described, but the diagnostic and prognostic role of antigenemia is not well understood. This study aimed to determine the frequency, duration, and concentration of nucleocapsid antigen in plasma and its association with coronavirus disease 2019 (COVID-19) severity. METHODS: We utilized an ultrasensitive electrochemiluminescence immunoassay targeting SARS-CoV-2 nucleocapsid antigen to evaluate 777 plasma samples from 104 individuals with COVID-19. We compared plasma antigen to respiratory nucleic acid amplification testing (NAAT) in 74 individuals with COVID-19 from samples collected ±1 day of diagnostic respiratory NAAT and in 52 SARS-CoV-2-negative individuals. We used Kruskal-Wallis tests, multivariable logistic regression, and mixed-effects modeling to evaluate whether plasma antigen concentration was associated with disease severity. RESULTS: Plasma antigen had 91.9% (95% CI 83.2%-97.0%) clinical sensitivity and 94.2% (84.1%-98.8%) clinical specificity. Antigen-negative plasma samples belonged to patients with later respiratory cycle thresholds (Ct) when compared with antigen-positive plasma samples. Median plasma antigen concentration (log10 fg/mL) was 5.4 (interquartile range 3.9-6.0) in outpatients, 6.0 (5.4-6.5) in inpatients, and 6.6 (6.1-7.2) in intensive care unit (ICU) patients. In models adjusted for age, sex, diabetes, and hypertension, plasma antigen concentration at diagnosis was associated with ICU admission [odds ratio 2.8 (95% CI 1.2-6.2), P=.01] but not with non-ICU hospitalization. Rate of antigen decrease was not associated with disease severity. CONCLUSIONS: SARS-CoV-2 plasma nucleocapsid antigen exhibited comparable diagnostic performance to upper respiratory NAAT, especially among those with late respiratory Ct. In addition to currently available tools, antigenemia may facilitate patient triage to optimize intensive care utilization.


Subject(s)
Antigens, Viral/blood , COVID-19 Testing/methods , COVID-19 , Coronavirus Nucleocapsid Proteins/blood , COVID-19/diagnosis , Electrochemical Techniques , Hospitalization , Humans , Immunoassay , Luminescent Measurements , Nucleocapsid , Phosphoproteins/blood , SARS-CoV-2 , Sensitivity and Specificity
17.
Front Immunol ; 12: 739037, 2021.
Article in English | MEDLINE | ID: covidwho-1448729

ABSTRACT

Background: Transfusion of COVID-19 convalescent plasma (CCP) containing high titers of anti-SARS-CoV-2 antibodies serves as therapy for COVID-19 patients. Transfusions early during disease course was found to be beneficial. Lessons from the SARS-CoV-2 pandemic could inform early responses to future pandemics and may continue to be relevant in lower resource settings. We sought to identify factors correlating to high antibody titers in convalescent plasma donors and understand the magnitude and pharmacokinetic time course of both transfused antibody titers and the endogenous antibody titers in transfused recipients. Methods: Plasma samples were collected up to 174 days after convalescence from 93 CCP donors with mild disease, and from 16 COVID-19 patients before and after transfusion. Using ELISA, anti-SARS-CoV-2 Spike RBD, S1, and N-protein antibodies, as well as capacity of antibodies to block ACE2 from binding to RBD was measured in an in vitro assay. As an estimate for viral load, viral RNA and N-protein plasma levels were assessed in COVID-19 patients. Results: Anti-SARS-CoV-2 antibody levels and RBD-ACE2 blocking capacity were highest within the first 60 days after symptom resolution and markedly decreased after 120 days. Highest antibody titers were found in CCP donors that experienced fever. Effect of transfused CCP was detectable in COVID-19 patients who received high-titer CCP and had not seroconverted at the time of transfusion. Decrease in viral RNA was seen in two of these patients. Conclusion: Our results suggest that high titer CCP should be collected within 60 days after recovery from donors with past fever. The much lower titers conferred by transfused antibodies compared to endogenous production in the patient underscore the importance of providing CCP prior to endogenous seroconversion.


Subject(s)
COVID-19/therapy , Convalescence , SARS-CoV-2/immunology , Seroconversion , Adult , Antibodies, Neutralizing/blood , Antibodies, Neutralizing/immunology , Antibodies, Viral/blood , Antibodies, Viral/immunology , Antigens, Viral/blood , Blood Donors , COVID-19/blood , COVID-19/immunology , Female , Humans , Immunization, Passive , Kinetics , Male , Middle Aged , Outpatients , RNA, Viral/blood
18.
EBioMedicine ; 67: 103355, 2021 May.
Article in English | MEDLINE | ID: covidwho-1385438

ABSTRACT

BACKGROUND: There is increasing concern that persistent infection of SARS-CoV-2 within immunocompromised hosts could serve as a reservoir for mutation accumulation and subsequent emergence of novel strains with the potential to evade immune responses. METHODS: We describe three patients with acute lymphoblastic leukemia who were persistently positive for SARS-CoV-2 by real-time polymerase chain reaction. Viral viability from longitudinally-collected specimens was assessed. Whole-genome sequencing and serological studies were performed to measure viral evolution and evidence of immune escape. FINDINGS: We found compelling evidence of ongoing replication and infectivity for up to 162 days from initial positive by subgenomic RNA, single-stranded RNA, and viral culture analysis. Our results reveal a broad spectrum of infectivity, host immune responses, and accumulation of mutations, some with the potential for immune escape. INTERPRETATION: Our results highlight the potential need to reassess infection control precautions in the management and care of immunocompromised patients. Routine surveillance of mutations and evaluation of their potential impact on viral transmission and immune escape should be considered.


Subject(s)
COVID-19/immunology , Immune Evasion , Mutation , Precursor Cell Lymphoblastic Leukemia-Lymphoma/virology , SARS-CoV-2/genetics , COVID-19/virology , Child, Preschool , Evolution, Molecular , Female , Genome, Viral , High-Throughput Nucleotide Sequencing , Humans , Immunity, Humoral , Male , Precursor Cell Lymphoblastic Leukemia-Lymphoma/immunology , SARS-CoV-2/classification , SARS-CoV-2/immunology , Sequence Analysis, RNA , Whole Genome Sequencing , Young Adult
20.
Nature ; 596(7872): 410-416, 2021 08.
Article in English | MEDLINE | ID: covidwho-1305364

ABSTRACT

The emergency use authorization of two mRNA vaccines in less than a year from the emergence of SARS-CoV-2 represents a landmark in vaccinology1,2. Yet, how mRNA vaccines stimulate the immune system to elicit protective immune responses is unknown. Here we used a systems vaccinology approach to comprehensively profile the innate and adaptive immune responses of 56 healthy volunteers who were vaccinated with the Pfizer-BioNTech mRNA vaccine (BNT162b2). Vaccination resulted in the robust production of neutralizing antibodies against the wild-type SARS-CoV-2 (derived from 2019-nCOV/USA_WA1/2020) and, to a lesser extent, the B.1.351 strain, as well as significant increases in antigen-specific polyfunctional CD4 and CD8 T cells after the second dose. Booster vaccination stimulated a notably enhanced innate immune response as compared to primary vaccination, evidenced by (1) a greater frequency of CD14+CD16+ inflammatory monocytes; (2) a higher concentration of plasma IFNγ; and (3) a transcriptional signature of innate antiviral immunity. Consistent with these observations, our single-cell transcriptomics analysis demonstrated an approximately 100-fold increase in the frequency of a myeloid cell cluster enriched in interferon-response transcription factors and reduced in AP-1 transcription factors, after secondary immunization. Finally, we identified distinct innate pathways associated with CD8 T cell and neutralizing antibody responses, and show that a monocyte-related signature correlates with the neutralizing antibody response against the B.1.351 variant. Collectively, these data provide insights into the immune responses induced by mRNA vaccination and demonstrate its capacity to prime the innate immune system to mount a more potent response after booster immunization.


Subject(s)
Adaptive Immunity , Antibodies, Viral/immunology , COVID-19 Vaccines/immunology , COVID-19/immunology , Immunity, Innate , T-Lymphocytes/immunology , Vaccinology , Adult , Aged , Antibodies, Neutralizing/immunology , Autoantibodies/immunology , BNT162 Vaccine , COVID-19 Vaccines/administration & dosage , Female , Humans , Immunization, Secondary , Male , Middle Aged , Single-Cell Analysis , Spike Glycoprotein, Coronavirus/immunology , Transcription, Genetic , Transcriptome/genetics , Young Adult
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