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1.
Curr Top Med Chem ; 21(14): 1235-1250, 2021 Oct 05.
Article in English | MEDLINE | ID: covidwho-1441869

ABSTRACT

BACKGROUND: Virus-like Particles (VLPs) are non-genetic multimeric nanoparticles synthesized through in vitro or in vivo self-assembly of one or more viral structural proteins. Immunogenicity and safety of VLPs make them ideal candidates for vaccine development and efficient nanocarriers for foreign antigens or adjuvants to activate the immune system. AIMS: The present study aimed to design and synthesize a chimeric VLP vaccine of the phage Qbeta (Qß) coat protein presenting the universal epitope of the coronavirus. METHODS: The RNA phage Qß coat protein was designed and synthesized, denoted as Qbeta. The CoV epitope, a universal epitope of coronavirus, was inserted into the C-terminal of Qbeta using genetic recombination, designated as Qbeta-CoV. The N-terminal of Qbeta-CoV was successively inserted into the TEV restriction site using mCherry red fluorescent label and modified affinity purified histidine label 6xHE, which was denoted as HE-Qbeta-CoV. Isopropyl ß-D-1-thiogalactopyranoside (IPTG) assessment revealed the expression of Qbeta, Qbeta-CoV, and HE-Qbeta-CoV in the BL21 (DE3) cells. The fusion protein was purified by salting out using ammonium sulfate and affinity chromatography. The morphology of particles was observed using electron microscopy. The female BALB/C mice were immunized intraperitoneally with the Qbeta-CoV and HE-Qbeta-- CoV chimeric VLPs vaccines and their sera were collected for the detection of antibody level and antibody titer using ELISA. The serum is used for the neutralization test of the three viruses of MHV, PEDV, and PDCoV. RESULTS: The results revealed that the fusion proteins Qbeta, Qbeta-CoV, and HE-Qbeta-CoV could all obtain successful expression. Particles with high purity were obtained after purification; the chimeric particles of Qbeta-CoV and HE-Qbeta-CoV were found to be similar to Qbeta particles in morphology and formed chimeric VLPs. In addition, two chimeric VLP vaccines induced specific antibody responses in mice and the antibodies showed certain neutralizing activity. CONCLUSION: The successful construction of the chimeric VLPs of the phage Qß coat protein presenting the universal epitope of coronavirus provides a vaccine form with potential clinical applications for the treatment of coronavirus disease.


Subject(s)
Antibodies, Neutralizing/immunology , Capsid Proteins/immunology , Coronavirus/immunology , Vaccines, Virus-Like Particle/immunology , Animals , Antigens, Viral/genetics , Antigens, Viral/immunology , Enzyme-Linked Immunosorbent Assay , Female , Mice, Inbred BALB C , Microscopy, Electron, Scanning , Phylogeny , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/isolation & purification , Recombinant Fusion Proteins/metabolism , Vaccines, Virus-Like Particle/genetics , Viral Proteins/genetics
2.
Commun Biol ; 4(1): 486, 2021 04 20.
Article in English | MEDLINE | ID: covidwho-1195630

ABSTRACT

There is an ongoing need of developing sensitive and specific methods for the determination of SARS-CoV-2 seroconversion. For this purpose, we have developed a multiplexed flow cytometric bead array (C19BA) that allows the identification of IgG and IgM antibodies against three immunogenic proteins simultaneously: the spike receptor-binding domain (RBD), the spike protein subunit 1 (S1) and the nucleoprotein (N). Using different cohorts of samples collected before and after the pandemic, we show that this assay is more sensitive than ELISAs performed in our laboratory. The combination of three viral antigens allows for the interrogation of full seroconversion. Importantly, we have detected N-reactive antibodies in COVID-19-negative individuals. Here we present an immunoassay that can be easily implemented and has superior potential to detect low antibody titers compared to current gold standard serology methods.


Subject(s)
Antibodies, Viral/immunology , COVID-19/diagnosis , Flow Cytometry/methods , Nucleoproteins/immunology , SARS-CoV-2/immunology , Seroconversion , Antigens, Viral/immunology , COVID-19/epidemiology , COVID-19/virology , Humans , Immunoassay/methods , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Pandemics , Reproducibility of Results , SARS-CoV-2/physiology , Sensitivity and Specificity
3.
J Blood Med ; 12: 157-164, 2021.
Article in English | MEDLINE | ID: covidwho-1181235

ABSTRACT

BACKGROUND: We investigated the utility of an automated chemiluminescent SARS-CoV-2 IgG antibody assay platform in quantifying the amount of binding antibodies present in donated convalescent plasma. METHODS: A total of 179 convalescent plasma units were analyzed for the presence of SARS-CoV-2 IgG antibodies using the Beckman-Coulter chemiluminescent immunoassay (CLIA) platform. The equipment-derived numerical values (S/Co ratio) were recorded. Aliquots from the same units were subjected to enzyme-linked immunosorbent assay (ELISA) that detects IgG antibodies against the receptor-binding domain (RBD) of the SARS-CoV-2 S1 protein. The relationship between ELISA titers and CLIA S/Co values was analyzed using linear regression and receiver operating characteristics (ROC) curve. RESULTS: Twenty-one samples (11.7%) had S/Co values of less than 1.0 and were deemed negative for antibodies and convalescent plasma had S/Co values between >1.0 and 5.0 (70/179, 39.1%). Fifteen units (8.4%) had negative ELISA titer. The majority of the units (95/179. 53.1%) had titers ≥1:1024. The sensitivities of ELISA to CLIA were comparable (90.5% vs 88.3%, respectively; p=0.18). There was positive linear correlation between CLIA S/Co values and ELISA IgG titer (Rho = 0.75; Spearman's rank = 0.82, p-value = <0.0001). The agreement between the two methods was fair, with a κ index of 0.2741. Using the ROC analysis, we identified a CLIA S/Co cutoff value of 8.2, which gives a sensitivity of 90% and a specificity of 82% in predicting a titer dilution of ≥1:1024. CONCLUSION: The utility of automated antibody detection systems can be extended from simply a screening method to a semi-quantitative and quantitative functional antibody analysis. CLIA S/Co values can be used to reliably estimate the ELISA antibody titer. Incorporation of chemiluminescent-based methods can provide rapid, cost-effective means of identifying anti-SARS-CoV-2 antibody titers in donated plasma for use in the treatment of COVID-19 infection.

4.
Ann Rheum Dis ; 80(10): 1306-1311, 2021 10.
Article in English | MEDLINE | ID: covidwho-1150213

ABSTRACT

INTRODUCTION: In light of the SARS-CoV-2 pandemic, protecting vulnerable groups has become a high priority. Persons at risk of severe disease, for example, those receiving immunosuppressive therapies for chronic inflammatory cdiseases (CIDs), are prioritised for vaccination. However, data concerning generation of protective antibody titres in immunosuppressed patients are scarce. Additionally, mRNA vaccines represent a new vaccine technology leading to increased insecurity especially in patients with CID. OBJECTIVE: Here we present for the first time, data on the efficacy and safety of anti-SARS-CoV-2 mRNA vaccines in a cohort of immunosuppressed patients as compared with healthy controls. METHODS: 42 healthy controls and 26 patients with CID were included in this study (mean age 37.5 vs 50.5 years). Immunisations were performed according to national guidelines with mRNA vaccines. Antibody titres were assessed by ELISA before initial vaccination and 7 days after secondary vaccination. Disease activity and side effects were assessed prior to and 7 days after both vaccinations. RESULTS: Anti-SARS-CoV-2 antibodies as well as neutralising activity could be detected in all study participants. IgG titres were significantly lower in patients as compared with controls (2053 binding antibody units (BAU)/mL ±1218 vs 2685±1102). Side effects were comparable in both groups. No severe adverse effects were observed, and no patients experienced a disease flare. CONCLUSION: We show that SARS-CoV-2 mRNA vaccines lead to development of antibodies in immunosuppressed patients without considerable side effects or induction of disease flares. Despite the small size of this cohort, we were able to demonstrate the efficiency and safety of mRNA vaccines in our cohort.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/prevention & control , Immunocompromised Host/immunology , Immunogenicity, Vaccine/immunology , Inflammation/drug therapy , Adult , Aged , Aged, 80 and over , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Cohort Studies , Female , Humans , Immunosuppressive Agents/therapeutic use , Inflammation/immunology , Male , Middle Aged , Rheumatic Diseases/drug therapy , Rheumatic Diseases/immunology , SARS-CoV-2 , Vaccines, Synthetic/immunology
5.
Virol J ; 18(1): 16, 2021 01 12.
Article in English | MEDLINE | ID: covidwho-1059645

ABSTRACT

BACKGROUND: SARS-CoV-2 is a novel coronavirus that emerged in 2019 and is now classified in the genus Coronavirus with closely related SARS-CoV. SARS-CoV-2 is highly pathogenic in humans and is classified as a biosafety level (BSL)-3 pathogen, which makes manipulating it relatively difficult due to its infectious nature. METHODS: To circumvent the need for BSL-3 laboratories, an alternative assay was developed that avoids live virus and instead uses a recombinant VSV expressing luciferase and possesses the full length or truncated spike proteins of SARS-CoV-2. Furthermore, to measure SARS-CoV-2 neutralizing antibodies under BSL2 conditions, a chemiluminescence reduction neutralization test (CRNT) for SARS-CoV-2 was developed. The neutralization values of the serum samples collected from hospitalized patients with COVID-19 or SARS-CoV-2 PCR-negative donors against the pseudotyped virus infection evaluated by the CRNT were compared with antibody titers determined from an enzyme-linked immunosorbent assay (ELISA) or an immunofluorescence assay (IFA). RESULTS: The CRNT, which used whole blood collected from hospitalized patients with COVID-19, was also examined. As a result, the inhibition of pseudotyped virus infection was specifically observed in both serum and whole blood and was also correlated with the results of the IFA. CONCLUSIONS: In conclusion, the CRNT for COVID-19 is a convenient assay system that can be performed in a BSL-2 laboratory with high specificity and sensitivity for evaluating the occurrence of neutralizing antibodies against SARS-CoV-2.


Subject(s)
Antibodies, Neutralizing/blood , COVID-19 Serological Testing/methods , COVID-19/blood , Neutralization Tests/methods , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Vesicular stomatitis Indiana virus/genetics , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/blood , Antibodies, Viral/immunology , COVID-19/immunology , Cell Line , Convalescence , Humans , Inhibitory Concentration 50 , Luminescence , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics
6.
Trials ; 21(1): 883, 2020 Oct 26.
Article in English | MEDLINE | ID: covidwho-892368

ABSTRACT

OBJECTIVES: General: To assess the safety, efficacy and dose response of convalescent plasma (CP) transfusion in severe COVID-19 patients Specific: a. To identify the appropriate effective dose of CP therapy in severe patients b. To identify the efficacy of the therapy with their end point based on clinical improvement within seven days of treatment or until discharge whichever is later and in-hospital mortality c. To assess the clinical improvement after CP transfusion in severe COVID-19 patients d. To assess the laboratory improvement after CP transfusion in severe COVID-19 patients TRIAL DESIGN: This is a multicentre, multi-arm phase II Randomised Controlled Trial. PARTICIPANTS: Age and sex matched COVID-19 positive (by RT-PCR) severe cases will be enrolled in this trial. Severe case is defined by the World Health Organization (W.H.O) clinical case definition. The inclusion criteria are 1. Respiratory rate > 30 breaths/min; PLUS 2. Severe respiratory distress; or SpO2 ≤ 88% on room air or PaO2/FiO2≤ 300 mm of Hg, PLUS 3. Radiological (X-ray or CT scan) evidence of bilateral lung infiltrate, AND OR 4. Systolic BP < 90 mm of Hg or diastolic BP <60 mm of Hg. AND/OR 5. Criteria 1 to 4 AND or patient in ventilator support Patients' below18 years, pregnant and lactating women, previous history of allergic reaction to plasma, patients who have already received plasma from a different source will be excluded. Patients will be enrolled at Bangabandhu Sheikh Mujib Medical University (BSMMU) hospital, Dhaka medical college hospital (DMCH) and Mugda medical college hospital (MuMCH). Apheretic plasma will be collected at the transfusion medicine department of SHNIBPS hospital, ELISA antibody titre will be done at BSMMU and CMBT and neutralizing antibody titre will be checked in collaboration with the University of Oxford. Patients who have recovered from COVID-19 will be recruited as donors of CP. The recovery criteria are normality of body temperature for more than 3 days, resolution of respiratory symptoms, two consecutively negative results of sputum SARS-CoV-2 by RT-PCR assay (at least 24 hours apart) 22 to 35 days of post onset period, and neutralizing antibody titre ≥ 1:160. INTERVENTION AND COMPARATOR: This RCT consists of three arms, a. standard care, b. standard care and 200 ml CP and c. standard care and 400 ml CP. Patients will receive plasma as a single transfusion. Intervention arms will be compared to the standard care arm. MAIN OUTCOMES: The primary outcome will be time to clinical improvement within seven days of treatment or until discharge whichever is later and in-hospital mortality. The secondary outcome would be improvement of laboratory parameters after therapy (neutrophil, lymphocyte ratio, CRP, serum ferritin, SGPT, SGOT, serum creatinine and radiology), length of hospital stay, length of ICU stay, reduction in proportion of deaths, requirement of ventilator and duration of oxygen and ventilator support. RANDOMISATION: Randomization will be done by someone not associated with the care or assessment of the patients by means of a computer generated random number table using an allocation ratio of 1:1:1. BLINDING (MASKING): This is an open level study; neither the physician nor the patients will be blinded. However, the primary and secondary outcome (oxygen saturations, PaO2/FiO2, BP, day specific laboratory tests) will be recorded using an objective automated method; the study staff will not be able to influence the recording of these data. NUMBER TO BE RANDOMISED (SAMPLE SIZE): No similar study has been performed previously. Therefore no data are available that could be used to generate a sample size calculation. This phase II study is required to provide some initial data on efficacy and safety that will allow design of a larger study. The trial will recruit 60 participants (20 in each arm). TRIAL STATUS: Protocol version 1.4 dated May 5, 2020 and amended version 1.5, dated June 16, 2020. First case was recruited on May 27, 2020. By August 10, 2020, the trial had recruited one-third (21 out of 60) of the participants. The recruitment is expected to finish by October 31, 2020. TRIAL REGISTRATION: Clinicaltrials.gov ID: NCT04403477 . Registered 26 May, 2020 FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trial's website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this letter serves as a summary of the key elements of the full protocol.


Subject(s)
Betacoronavirus/genetics , Blood Transfusion/methods , Coronavirus Infections/therapy , Pneumonia, Viral/therapy , Bangladesh/epidemiology , COVID-19 , Coronavirus Infections/epidemiology , Coronavirus Infections/virology , Dose-Response Relationship, Immunologic , Female , Hospital Mortality/trends , Humans , Immunization, Passive/adverse effects , Immunization, Passive/methods , Male , Pandemics , Patient Discharge/statistics & numerical data , Pneumonia, Viral/epidemiology , Pneumonia, Viral/virology , SARS-CoV-2 , Safety , Severity of Illness Index , Time Factors , Treatment Outcome , Ventilators, Mechanical/statistics & numerical data
7.
Poult Sci ; 99(6): 2944-2954, 2020 Jun.
Article in English | MEDLINE | ID: covidwho-824735

ABSTRACT

This trial assessed the efficacy of a commercial essential oil (EO) product on the immune response to vaccination against Newcastle disease (ND) and subsequent challenge with virulent ND virus genotype VII (vNDv genotype VII) by using the following experimental groups of broiler chickens (Each group had 21 birds with 3 replicates in each, n = 7): NC (negative control), PC (positive control), VC (vaccinated), and VTC (vaccinated and treated with EOs). Moreover, in a trial to study the effect of EOs on vNDv genotype VII in vivo as a preventive or therapeutic measure, 2 additional ND-vaccinated groups were used (PRV: medicated 1 D before vNDv challenge for 5 D; and TTT: medicated 2 D after vNDv challenge for 5 D). In addition, the immune-modulatory effect of EOs on the avian influenza (AI), infectious bronchitis (IB), and infectious bursal disease (IBD) vaccines was assessed through the serological response. The use of EOs along with administration of ND vaccines (VTC) revealed a lower mortality rate (42.86%), clinical signs, and postmortem lesion score (11) than ND vaccines alone (VC) (52.28% mortality and score 15), in addition to lower hemagglutination inhibition (P < 0.05) (6.5 ± 0.46) and viral shedding (10 log 2.28 ± 0.24) titres 1 wk after challenge in comparison with VC (8.63 ± 0.65 and 10 log 3.29 ± 0.72, respectively). Nevertheless, the EOs mixture (VTC) (1952 ± 28.82) did not significantly (P > 0.05) improve growth performance compared with the nontreated birds (NC and VC) (1970 ± 19.56 and 1904 ± 38.66). EOs showed an antiviral effect on vNDv in vivo (in chickens) as a preventive measure (PRV) as well as some therapeutic effect (TTT) through decreasing the viral shedding titres (loNC0), mortality rate, and severity of clinical signs and postmortem lesions, in addition to serum malondialdhyde level. Regarding the other viruses, the EOs mixture did not improve the immune response to the AI and IB vaccines but significantly (P < 0.05) increased the ELISA antibody titre for IBD virus at the 28th D of age (2,108 ± 341.05). The studied EOs mixture showed an immune-stimulating response to ND and IBD vaccines, antiviral effect against ND virus, especially if administered before the challenge; however, it did not have a growth-promoting effect.


Subject(s)
Chickens , Immunity, Humoral , Newcastle Disease/prevention & control , Newcastle disease virus/immunology , Oils, Volatile/pharmacology , Poultry Diseases/prevention & control , Viral Vaccines/pharmacology , Animals , Immunity, Humoral/drug effects , Oils, Volatile/administration & dosage , Viral Vaccines/administration & dosage , Viral Vaccines/classification
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