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1.
Medicine (Baltimore) ; 100(50): e28192, 2021 Dec 17.
Article in English | MEDLINE | ID: covidwho-1583958

ABSTRACT

ABSTRACT: The study aims to investigate the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among ophthalmology unit staff throughout the first and second waves of the outbreak, in order to verify the effectiveness of the measures adopted in containing the contagion.A retrospective observational study was conducted involving staff members, who received a naso/oropharyngeal swab when complaining of SARS-CoV-2 symptoms and once a month as a screening measure. They were tested for SARS-CoV-2 antibodies as a screening measure during the first and the second wave. Clinical activities performed during the outbreak were compared with those performed during the same period in 2019 and correlated with the number of coronavirus disease-2019 eye care workers.Analysis included 25 workers. Clinical infection was 0% and 12% whereas the prevalence of SARS-CoV-2 antibodies ranged from 4% to 8% in the first and second wave, respectively. The increase in the prevalence of SARS-CoV-2 infection between the first and the second wave was not significant (1/25 vs 3/25, P = .6092). Clinical activities significantly decreased during the first wave compared with the same period in 2019 (3256 vs 10,075, P < .0001, -68% to 2019), but increased during the second wave (8208 vs 3256, P < .0001, +152% to the first wave).Despite the increase in routine activities during the second wave, we did not observe a significant increase in SARS-CoV-2 prevalence. Strict protection measures seemed to contain the rate of contagion among the ophthalmology unit members even in a high-volume clinical setting in one of the most affected area by the coronavirus disease-2019 outbreak.


Subject(s)
COVID-19 , Ophthalmologists , Antibodies, Viral/isolation & purification , COVID-19/epidemiology , Humans , Ophthalmologists/statistics & numerical data , Pandemics , Prevalence , SARS-CoV-2
2.
Lancet Respir Med ; 9(9): 999-1009, 2021 09.
Article in English | MEDLINE | ID: covidwho-1545508

ABSTRACT

BACKGROUND: Concurrent with the Pfizer-BioNTech BNT162b2 COVID-19 vaccine roll-out in Israel initiated on Dec 19, 2020, we assessed the early antibody responses and antibody kinetics after each vaccine dose in health-care workers of different ages and sexes, and with different comorbidities. METHODS: We did a prospective, single-centre, longitudinal cohort study at the Sheba Medical Centre (Tel-Hashomer, Israel). Eligible participants were health-care workers at the centre who had a negative anti-SARS-CoV-2 IgG assay before receiving the first dose of the intramuscular vaccine, and at least one serological antibody test after the first dose of the vaccine. Health-care workers with a positive SARS-CoV-2 PCR test before vaccination, a positive anti-SARS-CoV-2 IgG serology test before vaccination, or infection with COVID-19 after vaccination were excluded from the study. Participants were followed up weekly for 5 weeks after the first vaccine dose; a second dose was given at week 3. Serum samples were obtained at baseline and at each weekly follow-up, and antibodies were tested at 1-2 weeks after the first vaccine dose, at week 3 with the administration of the second vaccine dose, and at weeks 4-5 (ie, 1-2 weeks after the second vaccine dose). Participants with comorbidities were approached to participate in an enriched comorbidities subgroup, and at least two neutralising assays were done during the 5 weeks of follow-up in those individuals. IgG assays were done for the entire study population, whereas IgM, IgA, and neutralising antibody assays were done only in the enriched comorbidities subgroup. Concentrations of IgG greater than 0·62 sample-to-cutoff (s/co) ratio and of IgA greater than 1·1 s/co, and titres of neutralising antibodies greater than 10 were considered positive. Scatter plot and correlation analyses, logistic and linear regression analyses, and linear mixed models were used to investigate the longitudinal antibody responses. FINDINGS: Between Dec 19, 2020, and Jan 30, 2021, we obtained 4026 serum samples from 2607 eligible, vaccinated participants. 342 individuals were included in the enriched comorbidities subgroup. The first vaccine dose elicited positive IgG and neutralising antibody responses at week 3 in 707 (88·0%) of 803 individuals, and 264 (71·0%) of 372 individuals, respectively, which were rapidly increased at week 4 (ie, 1 week after the second vaccine dose) in 1011 (98·4%) of 1027 and 357 (96·5%) of 370 individuals, respectively. Over 4 weeks of follow-up after vaccination, a high correlation (r=0·92) was detected between IgG against the receptor-binding domain and neutralising antibody titres. First-dose induced IgG response was significantly lower in individuals aged 66 years and older (ratio of means 0·25, 95% CI 0·19-0·31) and immunosuppressed individuals (0·21, 0·14-0·31) compared with individuals aged 18·00-45·99 years and individuals with no immunosuppression, respectively. This disparity was partly abrogated following the second dose. Overall, endpoint regression analysis showed that lower antibody concentrations were consistently associated with male sex (ratio of means 0·84, 95% CI 0·80-0·89), older age (ie, ≥66 years; 0·64, 0·58-0·71), immunosuppression (0·44, 0·33-0·58), and other specific comorbidities: diabetes (0·88, 0·79-0·98), hypertension (0·90, 0·82-0·98), heart disease (0·86, 0·75-1·00), and autoimmune diseases (0·82, 0·73-0·92). INTERPRETATION: BNT162b2 vaccine induces a robust and rapid antibody response. The significant correlation between receptor-binding domain IgG antibodies and neutralisation titres suggests that IgG antibodies might serve as a correlate of neutralisation. The second vaccine dose is particularly important for older and immunosuppressed individuals, highlighting the need for timely second vaccinations and potentially a revaluation of the long gap between doses in some countries. Antibody responses were reduced in susceptible populations and therefore they might be more prone to breakthrough infections. FUNDING: Sheba Medical Center, Israel Ministry of Health.


Subject(s)
Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19 Vaccines/immunology , COVID-19/prevention & control , Health Personnel/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Antibodies, Viral/isolation & purification , COVID-19/epidemiology , COVID-19/immunology , COVID-19/virology , COVID-19 Vaccines/administration & dosage , Female , Follow-Up Studies , Humans , Immunity, Humoral , Immunogenicity, Vaccine , Israel/epidemiology , Longitudinal Studies , Male , Middle Aged , Pandemics/prevention & control , Prospective Studies , SARS-CoV-2/immunology , Vaccination/methods , Vaccination/statistics & numerical data , Young Adult
3.
Anal Bioanal Chem ; 413(29): 7251-7263, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1460298

ABSTRACT

Supply shortage for the development and production of preventive, therapeutic, and diagnosis tools during the COVID-19 pandemic is an important issue affecting the wealthy and poor nations alike. Antibodies and antigens are especially needed for the production of immunological-based testing tools such as point-of-care tests. Here, we propose a simple and quick magnetic nanoparticle (MNP)-based separation/isolation approach for the repurposing of infected human samples to produce specific antibodies and antigen cocktails. Initially, an antibody cocktail was purified from serums via precipitation and immunoaffinity chromatography. Purified antibodies were conjugated onto MNPs and used as an affinity matrix to separate antigens. The characterization process was performed by ELISA, SDS-PAGE, electrochemistry, isothermal titration calorimetry, and LC-Q-TOF-MS/MS analyses. The MNP-separated peptides can be used for mass spectrometry-based as well as paper-based lateral flow assay diagnostic. The exploitation of the current workflow for the development of efficient diagnostic tools, specific treatments, and fundamental research can significantly impact the present or eventual pandemic. This workflow can be considered as a two birds, one stone-like strategy.


Subject(s)
Antibodies, Viral/isolation & purification , Antigens, Viral/isolation & purification , COVID-19/diagnosis , Cost-Benefit Analysis , Immunoassay/economics , SARS-CoV-2/isolation & purification , Viremia/virology , Antibodies, Viral/blood , Antigens, Viral/blood , COVID-19/virology , Calorimetry , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Humans , SARS-CoV-2/immunology , Specimen Handling , Tandem Mass Spectrometry , Viremia/blood , Workflow
4.
MAbs ; 13(1): 1978130, 2021.
Article in English | MEDLINE | ID: covidwho-1442969

ABSTRACT

Recent years have seen unparalleled development of microfluidic applications for antibody discovery in both academic and pharmaceutical research. Microfluidics can support native chain-paired library generation as well as direct screening of antibody secreting cells obtained by rodent immunization or from the human peripheral blood. While broad diversities of neutralizing antibodies against infectious diseases such as HIV, Ebola, or COVID-19 have been identified from convalescent individuals, microfluidics can expedite therapeutic antibody discovery for cancer or immunological disease indications. In this study, a commercially available microfluidic device, Cyto-Mine, was used for the rapid identification of natively paired antibodies from rodents or human donors screened for specific binding to recombinant antigens, for direct screening with cells expressing the target of interest, and, to our knowledge for the first time, for direct broad functional IgG antibody screening in droplets. The process time from cell preparation to confirmed recombinant antibodies was four weeks. Application of this or similar microfluidic devices and methodologies can accelerate and enhance pharmaceutical antibody hit discovery.


Subject(s)
Antibodies, Neutralizing/isolation & purification , Immunoglobulin G/isolation & purification , Microfluidics/methods , Animals , Antibodies, Bacterial/immunology , Antibodies, Bacterial/isolation & purification , Antibodies, Monoclonal/isolation & purification , Antibodies, Viral/isolation & purification , Antibody Specificity , Antigens/immunology , Antigens, Neoplasm/immunology , Blood Preservation , COVID-19/immunology , Fluorescence Resonance Energy Transfer , Humans , Hybridomas/immunology , Immunomagnetic Separation , Lab-On-A-Chip Devices , Mice , Microfluidics/instrumentation , Muromonab-CD3/immunology , Plasma Cells , Recombinant Proteins/immunology , SARS-CoV-2/immunology , Tetanus Toxoid/immunology , Vaccination
5.
Nat Commun ; 12(1): 5652, 2021 09 27.
Article in English | MEDLINE | ID: covidwho-1440473

ABSTRACT

The emergence of numerous variants of SARS-CoV-2, the causative agent of COVID-19, has presented new challenges to the global efforts to control the COVID-19 pandemic. Here, we obtain two cross-neutralizing antibodies (7D6 and 6D6) that target Sarbecoviruses' receptor-binding domain (RBD) with sub-picomolar affinities and potently neutralize authentic SARS-CoV-2. Crystal structures show that both antibodies bind a cryptic site different from that recognized by existing antibodies and highly conserved across Sarbecovirus isolates. Binding of these two antibodies to the RBD clashes with the adjacent N-terminal domain and disrupts the viral spike. Both antibodies confer good resistance to mutations in the currently circulating SARS-CoV-2 variants. Thus, our results have direct relevance to public health as options for passive antibody therapeutics and even active prophylactics. They can also inform the design of pan-sarbecovirus vaccines.


Subject(s)
Antibodies, Viral/immunology , Broadly Neutralizing Antibodies/immunology , COVID-19/therapy , Immunization, Passive/methods , SARS-CoV-2/immunology , Animals , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/isolation & purification , Antibodies, Monoclonal/metabolism , Antibodies, Viral/administration & dosage , Antibodies, Viral/isolation & purification , Antibodies, Viral/metabolism , Binding Sites/genetics , Binding Sites/immunology , Broadly Neutralizing Antibodies/administration & dosage , Broadly Neutralizing Antibodies/isolation & purification , Broadly Neutralizing Antibodies/metabolism , CHO Cells , COVID-19/epidemiology , COVID-19/immunology , COVID-19/virology , Chlorocebus aethiops , Cricetulus , Epitopes/immunology , HEK293 Cells , Humans , Mice , Middle East Respiratory Syndrome Coronavirus/genetics , Middle East Respiratory Syndrome Coronavirus/immunology , Neutralization Tests , Pandemics/prevention & control , Protein Multimerization , Receptors, Virus/metabolism , SARS-CoV-2/genetics , Sf9 Cells , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , Vero Cells
6.
BMJ Case Rep ; 14(3)2021 Mar 24.
Article in English | MEDLINE | ID: covidwho-1388475

ABSTRACT

SARS-CoV-2 infection has recently been related to a spectrum of hyper-inflammatory states in children. There is a striking similarity between these hyper-inflammatory states and Kawasaki disease (KD). We present an interesting case of KD recurrence in a 10-year-old child, who had previously developed KD at 4 years of age. His symptoms included fever, maculopapular rash and altered sensorium. Investigations showed noticeably elevated inflammatory markers, and an echocardiography revealed dilated coronary arteries. SARS-CoV-2 IgG antibodies were positive. The child responded dramatically to intravenous immunoglobulin and intravenous methylprednisolone. It is possible that SARS-CoV-2 infection triggered the recurrence of KD in this child who might have been genetically predisposed to KD.


Subject(s)
COVID-19/complications , Mucocutaneous Lymph Node Syndrome/etiology , Anti-Inflammatory Agents/therapeutic use , Antibodies, Viral/isolation & purification , COVID-19/therapy , Child , Echocardiography/methods , Humans , Immunoglobulins, Intravenous/administration & dosage , Male , Methylprednisolone/therapeutic use , Mucocutaneous Lymph Node Syndrome/therapy , Mucocutaneous Lymph Node Syndrome/virology , Recurrence , SARS-CoV-2 , Treatment Outcome
7.
J Immunol Methods ; 496: 113096, 2021 09.
Article in English | MEDLINE | ID: covidwho-1349521

ABSTRACT

Serology or antibody tests for COVID-19 are designed to detect antibodies (mainly Immunoglobulin M (IgM) and Immunoglobulin G (IgG) produced in response to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS CoV-2) infection. In this study, 30 lateral flow immunoassays were tested using serum or plasma from patients with confirmed SARS CoV-2 infection. Negative serological controls were accessed from a well-characterised bank of sera which were stored prior to February 2020. Operational characteristics and ease of use of the assays are reported. 4/30 (13%) of kits (Zheihang Orient Gene COVID-19 IgG/IgM, Genrui Novel Coronavirus (2019-nCoV) IgG/IgM, Biosynex COVID-19 BSS IgG/IgM, Boson Biotech 2019-nCoV IgG/IgM) were recommended for SAHPRA approval based on kit sensitivity. Of these, only the Orientgene was recommended by SAHPRA in August 2020 for use within the approved national testing algorithm while the remaining three received limited authorization for evaluation. All kits evaluated work on the same basic principle of immunochromatography with minor differences noted in the shape and colour of cartridges, the amount of specimen volume required and the test duration. Performance of the lateral flow tests were similar to sensitivities and specificities reported in other studies. The cassettes of the majority of kits evaluated (90%) detected both IgG and IgM. Only 23% of kits evaluated contained all consumables required for point-of-care testing. The study highlights the need for thorough investigation of kits prior to implementation.


Subject(s)
Antibodies, Viral/isolation & purification , COVID-19 Serological Testing/instrumentation , COVID-19/diagnosis , Immunoassay/instrumentation , Reagent Kits, Diagnostic/statistics & numerical data , Antibodies, Viral/blood , Antibodies, Viral/immunology , COVID-19/blood , COVID-19/immunology , COVID-19/virology , COVID-19 Nucleic Acid Testing/statistics & numerical data , COVID-19 Serological Testing/statistics & numerical data , Humans , Immunoassay/statistics & numerical data , Immunoglobulin G/blood , Immunoglobulin G/immunology , Immunoglobulin G/isolation & purification , Immunoglobulin M/blood , Immunoglobulin M/immunology , Immunoglobulin M/isolation & purification , Point-of-Care Testing/statistics & numerical data , RNA, Viral/blood , RNA, Viral/isolation & purification , SARS-CoV-2/genetics , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification , Sensitivity and Specificity
8.
EMBO J ; 40(17): e108588, 2021 09 01.
Article in English | MEDLINE | ID: covidwho-1332432

ABSTRACT

The humoral immune response to SARS-CoV-2 results in antibodies against spike (S) and nucleoprotein (N). However, whilst there are widely available neutralization assays for S antibodies, there is no assay for N-antibody activity. Here, we present a simple in vitro method called EDNA (electroporated-antibody-dependent neutralization assay) that provides a quantitative measure of N-antibody activity in unpurified serum from SARS-CoV-2 convalescents. We show that N antibodies neutralize SARS-CoV-2 intracellularly and cell-autonomously but require the cytosolic Fc receptor TRIM21. Using EDNA, we show that low N-antibody titres can be neutralizing, whilst some convalescents possess serum with high titres but weak activity. N-antibody and N-specific T-cell activity correlates within individuals, suggesting N antibodies may protect against SARS-CoV-2 by promoting antigen presentation. This work highlights the potential benefits of N-based vaccines and provides an in vitro assay to allow the antibodies they induce to be tested.


Subject(s)
Antibodies, Neutralizing/isolation & purification , Antibodies, Viral/isolation & purification , COVID-19/blood , SARS-CoV-2/isolation & purification , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19/virology , Humans , Nucleoproteins/blood , Nucleoproteins/immunology , SARS-CoV-2/pathogenicity
9.
Transplant Proc ; 53(8): 2435-2437, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1322367

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a highly prevalent infectious disease. Currently, organs are not being transplanted from donors who are SARS-CoV-2 positive. It remains unclear as to how to differentiate active from recovered patients. We report our recent experience of a 3-month-old deceased organ donor who died as the result of an anoxic brain injury after a cardiopulmonary arrest (presumed sudden infant death syndrome). The child was born to a mother presumed to have coronavirus disease 2019. The donor tested negative for SARS-CoV-2 reverse transcriptase-polymerase chain reaction and positive for SARS-CoV-2 immunoglobulin A antibodies. We suspect this is the first known report of its kind and noteworthy for the organ donation and transplantation community.


Subject(s)
Antibodies, Viral/isolation & purification , COVID-19 , Tissue Donors , COVID-19/diagnosis , COVID-19/immunology , Humans , Infant , Organ Transplantation , SARS-CoV-2/immunology , Tissue and Organ Procurement
10.
Front Immunol ; 12: 683902, 2021.
Article in English | MEDLINE | ID: covidwho-1282386

ABSTRACT

Respiratory syncytial virus (RSV) is a public health concern that causes acute lower respiratory tract infection. So far, no vaccine candidate under development has reached the market and the only licensed product to prevent RSV infection in at-risk infants and young children is a monoclonal antibody (Synagis®). Polyclonal human anti-RSV hyper-immune immunoglobulins (Igs) have also been used but were superseded by Synagis® owing to their low titer and large infused volume. Here we report a new drug class of immunoglobulins, derived from human non hyper-immune plasma that was generated by an innovative bioprocess, called Ig cracking, combining expertises in plasma-derived products and affinity chromatography. By using the RSV fusion protein (F protein) as ligand, the Ig cracking process provided a purified and concentrated product, designated hyper-enriched anti-RSV IgG, composed of at least 15-20% target-specific-antibodies from normal plasma. These anti-RSV Ig displayed a strong in vitro neutralization effect on RSV replication. Moreover, we described a novel prophylactic strategy based on local nasal administration of this unique hyper-enriched anti-RSV IgG solution using a mouse model of infection with bioluminescent RSV. Our results demonstrated that very low doses of hyper-enriched anti-RSV IgG can be administered locally to ensure rapid and efficient inhibition of virus infection. Thus, the general hyper-enriched Ig concept appeared a promising approach and might provide solutions to prevent and treat other infectious diseases. Importance: Respiratory Syncytial Virus (RSV) is the major cause of acute lower respiratory infections in children, and is also recognized as a cause of morbidity in the elderly. There are still no vaccines and no efficient antiviral therapy against this virus. Here, we described an approach of passive immunization with a new class of hyper-enriched anti-RSV immunoglobulins (Ig) manufactured from human normal plasma. This new class of immunoglobulin plasma derived product is generated by an innovative bioprocess, called Ig cracking, which requires a combination of expertise in both plasma derived products and affinity chromatography. The strong efficacy in a small volume of these hyper-enriched anti-RSV IgG to inhibit the viral infection was demonstrated using a mouse model. This new class of immunoglobulin plasma-derived products could be applied to other pathogens to address specific therapeutic needs in the field of infectious diseases or even pandemics, such as COVID-19.


Subject(s)
Antibodies, Viral/administration & dosage , Immunization, Passive , Immunoglobulin G/administration & dosage , Respiratory Syncytial Virus Infections/prevention & control , Respiratory Syncytial Virus, Human/immunology , Administration, Intranasal , Animals , Antibodies, Viral/immunology , Antibodies, Viral/isolation & purification , Disease Models, Animal , Humans , Immunoglobulin G/immunology , Immunoglobulin G/isolation & purification , Lung/drug effects , Lung/virology , Neutralization Tests , Respiratory Syncytial Virus Infections/virology , Turbinates/drug effects , Turbinates/virology , Viral Fusion Proteins/immunology , Virus Replication/drug effects
11.
Transfus Apher Sci ; 60(5): 103193, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1272760

ABSTRACT

For more than a year the whole world is suffering from the COVID-19 pandemic with no treatment option in sight. Administration of plasma from convalescent donors containing anti-SARS-CoV-2 antibodies, though promising according to case reports, failed to show a clear benefit in a greater number of trials. One reason could be varying and low antibody contents in a majority of plasma units hampering standardization and clinical efficacy. Besides, other plasma components unnecessarily transfused like coagulation factors might promote hypercoagulation seen in severe COVID-19 etiopathology. We therefore hypothesized that instead of collecting whole plasma units, convalescent donors could donate solely immunoglobulins by undergoing immunoadsorption, a mode of therapy regularly applied in autoimmune diseases. Here, we report the results of the first two antibody donations performed at the University Hospital Düsseldorf. In both cases, immunoadsorptions were very well tolerated with no side effects. Collected and neutralized eluates were concentrated using tangential flow filtration increasing the concentration of immunoglobulins 10fold as compared to peripheral blood and leading to probably eight times more neutralizing antibodies than in one plasma unit. Therefore, immunoadsorption can be used as a method of antibody donation. Whether these donated antibodies can be used as passive immunization in acutely infected patients remains to be elucidated.


Subject(s)
Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19/therapy , Immunosorbent Techniques , SARS-CoV-2/immunology , Antibodies, Neutralizing/isolation & purification , Antibodies, Viral/isolation & purification , COVID-19/immunology , Convalescence , Humans , Immunization, Passive/methods
12.
Anal Bioanal Chem ; 413(18): 4645-4654, 2021 Jul.
Article in English | MEDLINE | ID: covidwho-1245612

ABSTRACT

Nucleic acid detection technology based on polymerase chain reaction (PCR) and antibody detection based on immunochromatography still have many problems such as false negatives for the diagnosis of coronavirus disease 2019 (COVID-19). Therefore, it is of great importance to develop new techniques to improve the diagnostic accuracy of COVID-19. We herein developed an ultrasensitive, rapid, and duplex digital enzyme-linked immunosorbent assay (dELISA) for simultaneous detection of spike (S-RBD) and nucleocapsid (N) proteins of SARS-CoV-2 based on a single molecule array. This assay effectively combines magnetic bead encoding technology and the ultrasensitive detection capability of a single molecule array. The detection strategies of S-RBD protein and N-protein exhibited wide response ranges of 0.34-1065 pg/mL and 0.183-338 pg/mL with detection limits of 20.6 fg/mL and 69.8 fg/mL, respectively. It is a highly specific method for the simultaneous detection of S-RBD protein and N-protein and has minimal interference from other blood proteins. Moreover, the spike assay showed a satisfactory and reproducible recovery rate for the detection of S-RBD protein and N-protein in serum samples. Overall, this work provides a highly sensitive method for the simultaneous detection of S-RBD protein and N-protein, which shows ultrasensitivity and high signal-to-noise ratio and contributes to improve the diagnosis accuracy of COVID-19.


Subject(s)
COVID-19/diagnosis , Coronavirus Nucleocapsid Proteins/isolation & purification , SARS-CoV-2/isolation & purification , Single Molecule Imaging/methods , Spike Glycoprotein, Coronavirus/isolation & purification , Antibodies, Viral/isolation & purification , Coronavirus Nucleocapsid Proteins/genetics , Enzyme-Linked Immunosorbent Assay/standards , Humans , Immunoassay/methods , Magnetics , Microspheres , Phosphoproteins/genetics , Phosphoproteins/isolation & purification , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/genetics
14.
Nat Protoc ; 16(7): 3639-3671, 2021 07.
Article in English | MEDLINE | ID: covidwho-1243308

ABSTRACT

As exemplified by the ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, there is a strong demand for rapid high-throughput isolation pipelines to identify potent neutralizing antibodies for prevention and therapy of infectious diseases. However, despite substantial progress and extensive efforts, the identification and production of antigen-specific antibodies remains labor- and cost-intensive. We have advanced existing concepts to develop a highly efficient high-throughput protocol with proven application for the isolation of potent antigen-specific antibodies against human immunodeficiency virus 1, hepatitis C virus, human cytomegalovirus, Middle East respiratory syndrome coronavirus, SARS-CoV-2 and Ebola virus. It is based on computationally optimized multiplex primer sets (openPrimeR), which guarantee high coverage of even highly mutated immunoglobulin gene segments as well as on optimized antibody cloning and production strategies. Here, we provide the detailed protocol, which covers all critical steps from sample collection to antibody production within 12-14 d.


Subject(s)
Antibodies, Neutralizing/isolation & purification , COVID-19/immunology , High-Throughput Screening Assays/methods , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/pharmacology , Antibodies, Neutralizing/immunology , Antibodies, Neutralizing/pharmacology , Antibodies, Viral/immunology , Antibodies, Viral/isolation & purification , Communicable Diseases , Humans , Immunoglobulin G/immunology , Pandemics , SARS-CoV-2/immunology
15.
J Clin Microbiol ; 59(5)2021 04 20.
Article in English | MEDLINE | ID: covidwho-1195815

ABSTRACT

Serological assays for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are needed to support clinical diagnosis and epidemiological investigations. Recently, assays for large-scale detection of total antibodies (Ab), immunoglobulin G (IgG), and IgM against SARS-CoV-2 antigens have been developed, but there are limited data on the diagnostic accuracy of these assays. This study was a Danish national collaboration and evaluated 15 commercial and one in-house anti-SARS-CoV-2 assays in 16 laboratories. Sensitivity was evaluated using 150 samples from individuals with asymptomatic, mild, or moderate COVID-19, nonhospitalized or hospitalized, confirmed by nucleic acid amplification tests (NAAT); samples were collected 13 to 73 days either from symptom onset or from positive NAAT (patients without symptoms). Specificity and cross-reactivity were evaluated in samples collected prior to the SARS-CoV-2 epidemic from >586 blood donors and patients with autoimmune diseases, cytomegalovirus or Epstein-Barr virus infections, and acute viral infections. A specificity of ≥99% was achieved by all total-Ab and IgG assays except one, DiaSorin Liaison XL IgG (97.2%). Sensitivities in descending order were Wantai ELISA total Ab (96.7%), CUH-NOVO in-house ELISA total Ab (96.0%), Ortho Vitros total Ab (95.3%), YHLO iFlash IgG (94.0%), Ortho Vitros IgG (93.3%), Siemens Atellica total Ab (93.2%), Roche Elecsys total Ab (92.7%), Abbott Architect IgG (90.0%), Abbott Alinity IgG (median 88.0%), DiaSorin Liaison XL IgG (median 84.6%), Siemens Vista total Ab (81.0%), Euroimmun/ELISA IgG (78.0%), and Snibe Maglumi IgG (median 78.0%). However, confidence intervals overlapped for several assays. The IgM results were variable, with the Wantai IgM ELISA showing the highest sensitivity (82.7%) and specificity (99%). The rate of seropositivity increased with time from symptom onset and symptom severity.


Subject(s)
Antibodies, Viral/isolation & purification , COVID-19 Serological Testing/methods , COVID-19/diagnosis , Immunoassay , Cytomegalovirus Infections , Enzyme-Linked Immunosorbent Assay , Epstein-Barr Virus Infections , Herpesvirus 4, Human , Humans , Immunoglobulin G/isolation & purification , Immunoglobulin M/isolation & purification , Laboratories , SARS-CoV-2 , Sensitivity and Specificity
16.
Orv Hetil ; 162(15): 563-570, 2021 04 02.
Article in Hungarian | MEDLINE | ID: covidwho-1167157

ABSTRACT

Összefoglaló. A koronavírus-betegség 2019 (COVID-19)-pandémia komoly kihívás elé állította nemcsak a mikrobiológiai laboratóriumokat, hanem az eredmények interpretálásában a klinikumban dolgozó kollégákat is. Az orvostudomány specializált világában az immunológiai és a fertozo betegségekkel kapcsolatos ismeretek az antimikrobás terápiás megoldások sikeressége, valamint a széles köru vakcináció miatt az idok folyamán számos szakterületen háttérbe szorultak, felfrissítésük sürgeto és elengedhetetlen része a pandémiával való megküzdésnek. A diagnosztikai vizsgálatok fontos eszközei a járvány megfékezésének, illetve a betegek ellátásának, azonban a vírus és az emberi szervezet interakciójának megértése elengedhetetlenül szükséges a korrekt epidemiológiai és gyógyászati véleményalkotáshoz. Jelen cikkünk az orvosi gyakorlat számára foglalja össze a súlyos akut légzoszervi szindrómát okozó koronavírus-2 (SARS-CoV-2) kimutatására, valamint az immunrendszer specifikus immunválaszának szerológiai vizsgálatára irányuló, gyakorlatban használatos módszereket, azok helyét, szerepét és értékelésük szempontjait a tudomány jelen állása szerint. Orv Hetil. 2021; 162(15): 563-570. Summary. The coronavirus disease 2019 (COVID-19) pandemic posed a serious challenge not only for microbiology laboratories, but also for the clinicians in interpretation of the results. In the specialized world of medicine, knowledge of immunological and infectious diseases has been relegated to the background in many disciplines over time due to the success of antimicrobial therapies and widespread vaccination, so updating them is an urgent and essential part of the fight against the pandemic. Diagnostic tests are important tools for controlling the epidemic and caring for patients, but understanding the interaction between the virus and the human body is essential to form a correct epidemiological and medical opinion. This paper summarizes the medical methods for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the serological testing of the specific immune response of the immune system, their place, role and criteria of their evaluation according to current scientific knowledge. Orv Hetil. 2021; 162(15): 563-570.


Subject(s)
Antibodies, Viral , Antigens, Viral , COVID-19 Serological Testing , COVID-19 , SARS-CoV-2 , Antibodies, Viral/isolation & purification , Antigens, Viral/isolation & purification , COVID-19/diagnosis , Humans , SARS-CoV-2/immunology
17.
BMJ Open ; 11(3): e046800, 2021 03 24.
Article in English | MEDLINE | ID: covidwho-1150238

ABSTRACT

OBJECTIVES: In Italy, the pandemic of COVID-19 resulted in congestion of hospitals and laboratories and probably determined an underestimation of the number of infected subjects, as the molecular diagnosis of SARS-CoV-2 infection was mainly performed on hospitalised patients. Therefore, limited data are available about the number of asymptomatic/paucisymptomatic subjects in the general population across time. To understand SARS-CoV-2 infection in the general population, we have developed a cross-sectional study (the 'UNIversity against CORoNavirus study') to investigate infection trends in asymptomatic/paucisymptomatic subjects in Milan (Italy), between March and June 2020. PARTICIPANTS: The study population included 2023 subjects asymptomatic at the enrolment. PRIMARY OUTCOME MEASURES: A nasal mid-turbinate swab for the detection of SARS-CoV-2 RNA and blood specimen for testing serum antibodies (immunoglobulin M (IgM) and IgG) were collected. RESULTS: Subjects showing positivity for the SARS-CoV-2 RNA and/or for anti-SARS-CoV-2 Ig is 237 (11.7%). Only 1.2% (n=25) of the total population had a positive nasal swab for SARS-CoV-2 and the large majority (21/25) of them were observed in March. A total of 226 subjects (11%) had IgM (n=19; 0.9%), IgG (n=155; 7.7%) or both (n=52; 2.6%) against SARS-CoV-2. Subjects with a present or past SARS-CoV-2 infection did not differ from other subjects as regards the number of cohabiting family members, travels, fever and upper and lower respiratory infection episodes. CONCLUSIONS: Results from the present study support the hypothesis that the actual spread of the virus in Lombardy was underestimated in the official records. However, as it is not known how long Ig persist, numbers should be taken cautiously.


Subject(s)
Antibodies, Viral/isolation & purification , COVID-19 Serological Testing , COVID-19/diagnosis , Immunoglobulin G/isolation & purification , Immunoglobulin M/isolation & purification , RNA, Viral/isolation & purification , Adult , COVID-19/blood , Cross-Sectional Studies , Female , Humans , Italy/epidemiology , Male , Middle Aged , SARS-CoV-2
18.
Nat Commun ; 12(1): 1577, 2021 03 11.
Article in English | MEDLINE | ID: covidwho-1132068

ABSTRACT

COVID-19 is a severe acute respiratory disease caused by SARS-CoV-2, a new recently emerged sarbecovirus. This virus uses the human ACE2 enzyme as receptor for cell entry, recognizing it with the receptor binding domain (RBD) of the S1 subunit of the viral spike protein. We present the use of phage display to select anti-SARS-CoV-2 spike antibodies from the human naïve antibody gene libraries HAL9/10 and subsequent identification of 309 unique fully human antibodies against S1. 17 antibodies are binding to the RBD, showing inhibition of spike binding to cells expressing ACE2 as scFv-Fc and neutralize active SARS-CoV-2 virus infection of VeroE6 cells. The antibody STE73-2E9 is showing neutralization of active SARS-CoV-2 as IgG and is binding to the ACE2-RBD interface. Thus, universal libraries from healthy human donors offer the advantage that antibodies can be generated quickly and independent from the availability of material from recovering patients in a pandemic situation.


Subject(s)
Angiotensin-Converting Enzyme 2/immunology , Antibodies, Neutralizing/genetics , Antibodies, Viral/genetics , COVID-19/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Angiotensin-Converting Enzyme 2/chemistry , Animals , Antibodies, Neutralizing/isolation & purification , Antibodies, Viral/isolation & purification , Antibody Affinity , COVID-19/epidemiology , Cell Line , Chlorocebus aethiops , Gene Library , Healthy Volunteers , Host Microbial Interactions/immunology , Humans , Immunoglobulin G/genetics , Immunoglobulin G/isolation & purification , Models, Molecular , Mutation , Neutralization Tests , Pandemics , Peptide Library , Protein Interaction Domains and Motifs , Recombinant Proteins/genetics , Recombinant Proteins/immunology , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/chemistry , Vero Cells
19.
Nature ; 593(7857): 136-141, 2021 05.
Article in English | MEDLINE | ID: covidwho-1127162

ABSTRACT

Transmission of SARS-CoV-2 is uncontrolled in many parts of the world; control is compounded in some areas by the higher transmission potential of the B.1.1.7 variant1, which has now been reported in 94 countries. It is unclear whether the response of the virus to vaccines against SARS-CoV-2 on the basis of the prototypic strain will be affected by the mutations found in B.1.1.7. Here we assess the immune responses of individuals after vaccination with the mRNA-based vaccine BNT162b22. We measured neutralizing antibody responses after the first and second immunizations using pseudoviruses that expressed the wild-type spike protein or a mutated spike protein that contained the eight amino acid changes found in the B.1.1.7 variant. The sera from individuals who received the vaccine exhibited a broad range of neutralizing titres against the wild-type pseudoviruses that were modestly reduced against the B.1.1.7 variant. This reduction was also evident in sera from some patients who had recovered from COVID-19. Decreased neutralization of the B.1.1.7 variant was also observed for monoclonal antibodies that target the N-terminal domain (9 out of 10) and the receptor-binding motif (5 out of 31), but not for monoclonal antibodies that recognize the receptor-binding domain that bind outside the receptor-binding motif. Introduction of the mutation that encodes the E484K substitution in the B.1.1.7 background to reflect a newly emerged variant of concern (VOC 202102/02) led to a more-substantial loss of neutralizing activity by vaccine-elicited antibodies and monoclonal antibodies (19 out of 31) compared with the loss of neutralizing activity conferred by the mutations in B.1.1.7 alone. The emergence of the E484K substitution in a B.1.1.7 background represents a threat to the efficacy of the BNT162b2 vaccine.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19 Vaccines/immunology , COVID-19/immunology , COVID-19/therapy , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Vaccines, Synthetic/immunology , Aged , Aged, 80 and over , Angiotensin-Converting Enzyme 2/metabolism , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/isolation & purification , Antibodies, Neutralizing/isolation & purification , Antibodies, Viral/isolation & purification , COVID-19/metabolism , COVID-19/virology , Female , HEK293 Cells , Humans , Immune Evasion/genetics , Immune Evasion/immunology , Immunization, Passive , Male , Middle Aged , Models, Molecular , Mutation , Neutralization Tests , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism , Vaccines, Synthetic/administration & dosage
20.
Int J Infect Dis ; 105: 374-376, 2021 Apr.
Article in English | MEDLINE | ID: covidwho-1121483

ABSTRACT

BACKGROUND: The emergence and rapid global spread of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) represents a major challenge to health services, and has disrupted social and economic activities worldwide. In Spain, the first pandemic wave started in mid-March 2020 and lasted for 3 months, requiring home confinement and strict lockdown. Following relaxation of the measures during the summer, a second wave commenced in mid-September 2020 and extended until Christmas 2020. METHODS: The two pandemic waves were compared using information collected from rapid diagnostic tests and polymerase chain reaction assays at one university clinic in Madrid, the epicentre of the pandemic in Spain. RESULTS: In total, 1569 individuals (968 during the first wave and 601 during the second wave) were tested for SARS-CoV-2-specific antibodies using fingerprick capillary blood. In addition, during the second wave, 346 individuals were tested for SARS-CoV-2-specific antigen using either oral swabs or saliva. The overall seroprevalence of first-time-tested individuals was 12.6% during the first wave and 7.7% during the second wave (P < 0.01). Seroconversions and seroreversions within 6 months occurred at low rates, both below 5%. During the second wave, 3.5% of tested individuals were SARS-CoV-2 antigen positive, with two cases considered as re-infections. Severe clinical symptoms occurred in a greater proportion of cases during the first wave compared with the second wave (27.8% vs 10.6%, respectively; P = 0.03). CONCLUSION: The cumulative seroprevalence of SARS-CoV-2 antibodies in Madrid at the end of 2020 was approximately 20%. Seroreversions within 6 months occurred in 4% of cases. Seroconversions and re-infections were clinically less severe during the second wave than during the first wave. Hypothetically, a lower viral inoculum as a result of social distancing, increased use of face masks, promotion of outdoor activities and restrictions on gatherings may have contributed to this lower pathogenicity.


Subject(s)
COVID-19/epidemiology , Pandemics , Adult , Antibodies, Viral/isolation & purification , Antigens, Viral/isolation & purification , COVID-19/diagnosis , Communicable Disease Control/methods , Humans , Male , Masks , Middle Aged , Physical Distancing , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification , Saliva/virology , Seroepidemiologic Studies , Spain/epidemiology
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