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1.
Vaccines (Basel) ; 10(2)2022 Feb 14.
Article in English | MEDLINE | ID: covidwho-1699506

ABSTRACT

The emergence of rapidly spreading variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses a major challenge to the ability of vaccines and therapeutic antibodies to provide immunity. These variants contain mutations of specific amino acids that might impede vaccine efficacy. BriLife® (rVSV-ΔG-spike) is a newly developed SARS-CoV-2 vaccine candidate currently in phase II clinical trials. It is based on a replication-competent vesicular stomatitis virus (VSV) platform. The rVSV-ΔG-spike contains several spontaneously acquired spike mutations that correspond to SARS-CoV-2 variants' mutations. We show that human sera from BriLife® vaccinees preserve comparable neutralization titers towards alpha, gamma, and delta variants and show less than a three-fold reduction in the neutralization capacity of beta and omicron compared to the original virus. Taken together, we show that human sera from BriLife® vaccinees overall maintain a neutralizing antibody response against all tested variants. We suggest that BriLife®-acquired mutations may prove advantageous against future SARS-CoV-2 VOCs.

2.
Vox Sang ; 117(2): 185-192, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1685455

ABSTRACT

BACKGROUND AND OBJECTIVES: Passive immunization using investigational COVID-19 convalescent plasma (CCP) is a promising therapeutic strategy and could improve outcome if transfused early and contain high levels of anti-SARS-CoV-2 antibodies. We report the management of a national CCP collection and distribution program in Israel. MATERIALS AND METHODS: From 1 April 2020 to 15 January 2021, 4020 volunteer donors donated 5221 CCP units and 837 (20.8%) donors donated more than once. Anti-nucleocapsid IgG antibodies were determined using chemiluminescent immunoassay method (Abbott). A statistical model based on repeated IgG tests in sequential donations was created to predict the time of antibody decline below sample/cut-off (S/CO) level of 4.0. RESULTS: Ninety-six percent of CCP donors suffered a mild disease or were asymptomatic. Older donors had higher antibody levels. Higher antibody levels (S/CO ≥4) were detected in 35.2% of the donors. Low positive (S/CO ≥1.4-3.99) were found in 37%, and 27.8% had undetectable antibodies (S/CO ≤1.4). The model predicted decrease antibody thresholds of 0.55%/day since the first CCP donation, providing guidance for the effective timing of future collections from donors with high antibody levels. CONCLUSIONS: An efficient CCP collection and distribution program was achieved, based on performing initial and repeated plasma collections, preferably from donors with higher antibody levels, and only antibody-rich units were supplied for therapeutic use. The inventory met the quantity and quality standards of the authorities, enabled to respond to the growing demand of the medical system and provide a product that may contribute to improve prognosis in patients with COVID-19.


Subject(s)
COVID-19 , Blood Donors , COVID-19/therapy , Humans , Immunization, Passive , Israel , SARS-CoV-2
3.
Vaccine ; 40(3): 428-431, 2022 01 24.
Article in English | MEDLINE | ID: covidwho-1612087

ABSTRACT

Currently approved anti-COVID-19 vaccines have been found to be safe and effective and almost 60% of Israeli residents are already vaccinated with BNT162b2 vaccine. This observational study was designed to evaluate the adverse events of vaccine reported by 61 healthcare workers at least 7 days after the 2nd vaccination, and to investigate the correlation of adverse events and anti-SARS-CoV-2 IgG antibody levels. The median participant's age was 51.25 years, 16 men and 45 women; 77% (44% of male and 84.5% of female participants) reported adverse events. Injection site pain, fatigue and fever were the most common symptoms, and significantly higher antibody levels (average 19,387 AU/mL) were found in participants who had fever compared to those who did not experience fever (average antibody levels of 9,977 AU/mL, p < 0.001). This finding corresponds to previous observations of higher anti-SARS-CoV-2 IgG antibody levels in COVID-19 patients presented with fever.


Subject(s)
COVID-19 , COVID-19 Vaccines , Female , Health Personnel , Humans , Male , Middle Aged , RNA, Messenger , SARS-CoV-2 , Vaccination
4.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-293181

ABSTRACT

BriLife® (rVSV- ΔG-spike) is a SARS-CoV-2 vaccine candidate based on vesicular stomatitis virus (VSV) platform. We show that sera from BriLife® vaccinees maintain neutralization capacity against alpha, beta, gamma and delta SARS-CoV-2 variants. BriLife® spontaneously-acquired spike mutations, corresponding with key SARS-CoV-2 variants mutations, may contribute to its efficacy against SARS-CoV-2 variants.

7.
Transfusion ; 61 Suppl 1: S313-S325, 2021 07.
Article in English | MEDLINE | ID: covidwho-1358635

ABSTRACT

BACKGROUND: The current global pandemic has created unprecedented challenges in the blood supply network. Given the recent shortages, there must be a civilian plan for massively bleeding patients when there are no blood products on the shelf. Recognizing that the time to death in bleeding patients is less than 2 h, timely resupply from unaffected locations is not possible. One solution is to transfuse emergency untested whole blood (EUWB), similar to the extensive military experience fine-tuned over the last 19 years. While this concept is anathema in current civilian transfusion practice, it seems prudent to have a vetted plan in place. METHODS AND MATERIALS: During the early stages of the 2020 global pandemic, a multidisciplinary and international group of clinicians with broad experience in transfusion medicine communicated routinely. The result is a planning document that provides both background information and a high-level guide on how to emergently deliver EUWB for patients who would otherwise die of hemorrhage. RESULTS AND CONCLUSIONS: Similar plans have been utilized in remote locations, both on the battlefield and in civilian practice. The proposed recommendations are designed to provide high-level guidance for experienced blood bankers, transfusion experts, clinicians, and health authorities. Like with all emergency preparedness, it is always better to have a well-thought-out and trained plan in place, rather than trying to develop a hasty plan in the midst of a disaster. We need to prevent the potential for empty shelves and bleeding patients dying for lack of blood.


Subject(s)
Blood Banks , Blood Banks/methods , Blood Preservation/methods , Blood Transfusion/methods , COVID-19/epidemiology , Civil Defense , Emergency Service, Hospital , Humans , Pandemics
8.
Sci Immunol ; 6(61)2021 07 29.
Article in English | MEDLINE | ID: covidwho-1334534

ABSTRACT

The spillover of animal coronaviruses (aCoVs) to humans has caused SARS, MERS, and COVID-19. While antibody responses displaying cross-reactivity between SARS-CoV-2 and seasonal/common cold human coronaviruses (hCoVs) have been reported, potential cross-reactivity with aCoVs and the diagnostic implications are incompletely understood. Here, we probed for antibody binding against all seven hCoVs and 49 aCoVs represented as 12,924 peptides within a phage-displayed antigen library. Antibody repertoires of 269 recovered COVID-19 patients showed distinct changes compared to 260 unexposed pre-pandemic controls, not limited to binding of SARS-CoV-2 antigens but including binding to antigens from hCoVs and aCoVs with shared motifs to SARS-CoV-2. We isolated broadly reactive monoclonal antibodies from recovered COVID-19 patients that bind a shared motif of SARS-CoV-2, hCoV-OC43, hCoV-HKU1, and several aCoVs, demonstrating that interspecies cross-reactivity can be mediated by a single immunoglobulin. Employing antibody binding data against the entire CoV antigen library allowed accurate discrimination of recovered COVID-19 patients from unexposed individuals by machine learning. Leaving out SARS-CoV-2 antigens and relying solely on antibody binding to other hCoVs and aCoVs achieved equally accurate detection of SARS-CoV-2 infection. The ability to detect SARS-CoV-2 infection without knowledge of its unique antigens solely from cross-reactive antibody responses against other hCoVs and aCoVs suggests a potential diagnostic strategy for the early stage of future pandemics. Creating regularly updated antigen libraries representing the animal coronavirome can provide the basis for a serological assay already poised to identify infected individuals following a future zoonotic transmission event.


Subject(s)
Antibodies, Viral/immunology , Antigens, Viral/immunology , Coronavirus Infections/immunology , Coronavirus/immunology , Peptide Library , Adolescent , Adult , Aged , Animals , Coronavirus Infections/diagnosis , Cross Reactions , Female , Humans , Male , Middle Aged , Young Adult , Zoonoses
11.
EClinicalMedicine ; 29: 100651, 2020 Dec.
Article in English | MEDLINE | ID: covidwho-933030

ABSTRACT

BACKGROUND: An Israeli national taskforce performed a multi-center clinical and analytical validation of seven serology assays to determine their utility and limitations for SARS-CoV-2 diagnosis. METHODS: Serology assays from Roche, Abbott, Diasorin, BioMerieux, Beckman-Coulter, Siemens, and an in-house RBD ELISA were included. Negative samples from 2391 individuals representative of the Israeli population, and 698 SARS-CoV-2 PCR positive patients, collected between March and May 2020, were analyzed. FINDINGS: Immunoassays sensitivities between 81.5%-89.4% and specificities between 97.7%-100% resulted in a profound impact on the expected Positive Predictive Value (PPV) in low (<15%) prevalence scenarios. No meaningful increase was detected in the false positive rate in children compared to adults. A positive correlation between disease severity and antibody titers, and no decrease in antibody titers in the first 8 weeks after PCR positivity was observed. We identified a subgroup of symptomatic SARS-CoV-2 positive patients (~5% of patients), who remained seronegative across a wide range of antigens, isotypes, and technologies. INTERPRETATION: The commercially available automated immunoassays exhibit significant differences in performance and expected PPV in low prevalence scenarios. The low false-positivity rate in under 20's suggests that cross-reactive immunity from previous CoV strains is unlikely to explain the milder disease course in children. Finding no decrease in antibody titers in the first 8 weeks is in contrast to some reports of short half-life for SARS-CoV-2 antibodies. The ~5% who were seronegative non-responders, using multiple assays in a population-wide manner, represents the proportion of patients that may be at risk for re-infection. FUNDING: Israel Ministry of Health.

13.
EClinicalMedicine ; 26: 100525, 2020 Sep.
Article in English | MEDLINE | ID: covidwho-753681

ABSTRACT

BACKGROUND: We assessed outcome of patients with moderate and severe COVID-19 following treatment with convalescent plasma (CP) and the association with IgG levels in transfused CP. METHODS: A prospective cohort study. Primary outcome was improvement at day 14 defined as alive, not on mechanical ventilation, and moderate, mild, or recovered from COVID-19. Antibody levels in CP units were unknown at the time of treatment. IgG against the spike protein S1 was subsequently measured by ELISA. Neutralizing antibodies titers were determined in a subset. Outcome was assessed in relation to the mean antibody level transfused to the patients (≤4.0 versus >4.0). FINDINGS: Of 49 patients, 11 (22.4%) had moderate, 38 (77.6%) had severe disease, 28 were ventilated. At day 14, 24 (49.0%) patients improved, 9 (18.4%) died, and 13 (26.5%) were ventilated. In 14/98 (14.3%) CP units IgG was < 1.1 (cutoff calibration) and in 60 (61.2%) ≤4.0. IgG level and neutralizing antibody titer were correlated (0.85 p < 0.001). In patients receiving ≤4.0 antibody levels, 11/30 improved (36.7%) versus 13/19 (68.4%) in patients receiving >4.0 odds ratio (OR) 0.267 [95% confidence interval (CI) 0.079-0.905], P = 0.030. In patients diagnosed >10 days prior to treatment, 4/14 (22.4%) improved in the ≤4.0 antibody group, versus 6/7 (85.7%) in the >4.0 antibody group, OR 0.048 (95% CI, 0.004-0.520), P = 0.007. No serious adverse events were reported. INTERPRETATION: Treatment with CP with higher levels of IgG against S1 may benefit patients with moderate and severe COVID-19. IgG against S1 level in CP predicts neutralization antibodies titers.

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