25 results on '"Limor Kliker"'
Search Results
2. The effect of ivermectin on the viral load and culture viability in early treatment of nonhospitalized patients with mild COVID-19 – a double-blind, randomized placebo-controlled trial
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Asaf Biber, Geva Harmelin, Dana Lev, Li Ram, Amit Shaham, Ital Nemet, Limor Kliker, Oran Erster, Michal Mandelboim, and Eli Schwartz
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Adult ,Microbiology (medical) ,Ivermectin ,Treatment Outcome ,Infectious Diseases ,Double-Blind Method ,SARS-CoV-2 ,Humans ,General Medicine ,Viral Load ,COVID-19 Drug Treatment - Abstract
Ivermectin, an antiparasitic agent, also has antiviral properties. In this study, we aimed to assess whether ivermectin has anti-SARS-CoV-2 activity.In this double-blinded trial, we compared patients receiving ivermectin for 3 days versus placebo in nonhospitalized adult patients with COVID-19. A reverse transcriptase-polymerase chain reaction from a nasopharyngeal swab was obtained at recruitment and every 2 days for at least 6 days. The primary endpoint was a reduction of viral load on the sixth day as reflected by cycle threshold level30 (noninfectious level). The primary outcome was supported by the determination of viral-culture viability.Of 867 patients screened, 89 were ultimately evaluated per-protocol (47 ivermectin and 42 placeboes). On day 6, the odds ratio (OR) was 2.62 (95% confidence interval [CI]: 1.09-6.31) in the ivermectin arm, reaching the endpoint. In a multivariable logistic regression model, the odds of a negative test on day 6 were 2.28 times higher in the ivermectin group but reached significance only on day 8 (OR 3.70; 95% CI: 1.19-11.49, P = 0.02). Culture viability on days 2 to 6 was positive in 13.0% (3/23) of ivermectin samples versus 48.2% (14/29) in the placebo group (P = 0.008).There were lower viral loads and less viable cultures in the ivermectin group, which shows its anti-SARS-CoV-2 activity. It could reduce transmission in these patients and encourage further studies with this drug.
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- 2022
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3. Ep300 sequestration to functionally distinct glucocorticoid receptor binding loci underlie rapid gene activation and repression
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Avital Sarusi Portuguez, Ivana Grbesa, Moran Tal, Rachel Deitch, Dana Raz, Limor Kliker, Ran Weismann, Michal Schwartz, Olga Loza, Leslie Cohen, Libi Marchenkov-Flam, Myong-Hee Sung, Tommy Kaplan, and Ofir Hakim
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Genetics - Abstract
The rapid transcriptional response to the transcription factor, glucocorticoid receptor (GR), including gene activation or repression, is mediated by the spatial association of genes with multiple GR binding sites (GBSs) over large genomic distances. However, only a minority of the GBSs have independent GR-mediated activating capacity, and GBSs with independent repressive activity were rarely reported. To understand the positive and negative effects of GR we mapped the regulatory environment of its gene targets. We show that the chromatin interaction networks of GR-activated and repressed genes are spatially separated and vary in the features and configuration of their GBS and other non-GBS regulatory elements. The convergence of the KLF4 pathway in GR-activated domains and the STAT6 pathway in GR-repressed domains, impose opposite transcriptional effects to GR, independent of hormone application. Moreover, the ROR and Rev-erb transcription factors serve as positive and negative regulators, respectively, of GR-mediated gene activation. We found that the spatial crosstalk between GBSs and non-GBSs provides a physical platform for sequestering the Ep300 co-activator from non-GR regulatory loci in both GR-activated and -repressed gene compartments. While this allows rapid gene repression, Ep300 recruitment to GBSs is productive specifically in the activated compartments, thus providing the basis for gene induction.
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- 2022
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4. Viral co-pathogens in COVID-19 acute respiratory syndrome – what did we learn from the first year of pandemic?
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Aseel Egbarye, Miran Odeh, Hilda Sherbany, Limor Kliker, Yael Aharon, Ital Nemet, Adleen Saffia, Shiraz Gefen-Halevi, Sharon Amit, Or Kriger, Eyal Leshem, Yuval Barak, Oswa Abu Hussein, Jacqueline Alfandari, Natasha Belausov, Rawan Khashab, Michal Mandelboim, Rachel Hamias, and Gillian Smollan
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Microbiology (medical) ,medicine.medical_specialty ,Coronavirus disease 2019 (COVID-19) ,business.industry ,SARS-CoV-2 ,co-infections ,COVID-19 ,Infectious and parasitic diseases ,RC109-216 ,General Medicine ,Article ,respiratory tract diseases ,Infectious Diseases ,Pandemic ,Emergency medicine ,medicine ,Humans ,Respiratory system ,business ,Multiplex Polymerase Chain Reaction ,Pandemics ,Respiratory Tract Infections - Abstract
Objective: : This study aimed to describe the distribution of respiratory pathogens and the occurrence of co-pathogens during the first year of the COVID-19 pandemic. Methods: We used a multiplex polymerase chain reaction (PCR) panel targeting 23 microorganisms to analyze the oro-pharyngeal samples of patients admitted to our hospital with acute respiratory infection (ARI) between March 1, 2020, and February 28, 2021. We matched 40 to 50 patients who were SARS-CoV-2 positive and SARS-CoV-2 negative per month for age and sex. Results: A total of 939 patients with multiplex PCR test results were included in the study. Respiratory pathogens where detected in only 8/476 (1.6%) patients with COVID-19 versus 87/463 (18.7%) patients with non–COVID-19 ARI patients. Diversity and rates of pathogens vastly differed from previous years but showed seasonal variance. Conclusion: Patients with SARS-CoV-2 infection presenting with ARI during the first year of the COVID-19 pandemic demonstrated paucity of respiratory co-pathogens.
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- 2022
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5. Fifth bivalent omicron BA.4/BA.5 vaccination neutralization of SARS-CoV-2 in heart transplant recipients
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Yael Peled, Arnon Afek, Jignesh K. Patel, Ehud Raanani, Amit Segev, Eilon Ram, Alexander Fardman, Roy Beigel, Nofar Atari, Limor Kliker, Bayan Abd Elkader, and Michal Mandelboim
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Pulmonary and Respiratory Medicine ,Transplantation ,Surgery ,Cardiology and Cardiovascular Medicine - Published
- 2023
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6. Immunogenicity of Omicron BA.1-adapted BNT162b2 vaccines: randomized trial, 3-month follow-up
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Noam Barda, Yaniv Lustig, Victoria Indenbaum, Daniel Zibly, Gili Joseph, Keren Asraf, Yael Weiss-Ottolenghi, Sharon Amit, Limor Kliker, Bayan Abd Elkader, Eytan Ben-Ami, Michal Canetti, Ravit Koren, Shiri Katz-Likvornik, Osnat Halpern, Ella Mendelson, Ram Doolman, Dror Harats, Yitshak Kreiss, Michal Mandelboim, and Gili Regev-Yochay
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Microbiology (medical) ,Infectious Diseases ,General Medicine - Published
- 2023
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7. Efficacy and safety of metabolic interventions for the treatment of severe COVID-19: in vitro, observational, and non-randomized open-label interventional study
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Avner Ehrlich, Konstantinos Ioannidis, Makram Nasar, Ismaeel Abu Alkian, Yuval Daskal, Nofar Atari, Limor Kliker, Nir Rainy, Matan Hofree, Sigal Shafran Tikva, Inbal Houri, Arrigo Cicero, Chiara Pavanello, Cesare R Sirtori, Jordana B Cohen, Julio A Chirinos, Lisa Deutsch, Merav Cohen, Amichai Gottlieb, Adina Bar-Chaim, Oren Shibolet, Michal Mandelboim, Shlomo L Maayan, and Yaakov Nahmias
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medicine ,General Immunology and Microbiology ,General Neuroscience ,cell biology ,Settore BIO/14 - Farmacologia ,viruses ,General Medicine ,General Biochemistry, Genetics and Molecular Biology - Abstract
Background:Viral infection is associated with a significant rewire of the host metabolic pathways, presenting attractive metabolic targets for intervention.Methods:We chart the metabolic response of lung epithelial cells to SARS-CoV-2 infection in primary cultures and COVID-19 patient samples and perform in vitro metabolism-focused drug screen on primary lung epithelial cells infected with different strains of the virus. We perform observational analysis of Israeli patients hospitalized due to COVID-19 and comparative epidemiological analysis from cohorts in Italy and the Veteran’s Health Administration in the United States. In addition, we perform a prospective non-randomized interventional open-label study in which 15 patients hospitalized with severe COVID-19 were given 145 mg/day of nanocrystallized fenofibrate added to the standard of care.Results:SARS-CoV-2 infection produced transcriptional changes associated with increased glycolysis and lipid accumulation. Metabolism-focused drug screen showed that fenofibrate reversed lipid accumulation and blocked SARS-CoV-2 replication through a PPARα-dependent mechanism in both alpha and delta variants. Analysis of 3233 Israeli patients hospitalized due to COVID-19 supported in vitro findings. Patients taking fibrates showed significantly lower markers of immunoinflammation and faster recovery. Additional corroboration was received by comparative epidemiological analysis from cohorts in Europe and the United States. A subsequent prospective non-randomized interventional open-label study was carried out on 15 patients hospitalized with severe COVID-19. The patients were treated with 145 mg/day of nanocrystallized fenofibrate in addition to standard-of-care. Patients receiving fenofibrate demonstrated a rapid reduction in inflammation and a significantly faster recovery compared to patients admitted during the same period.Conclusions:Taken together, our data suggest that pharmacological modulation of PPARα should be strongly considered as a potential therapeutic approach for SARS-CoV-2 infection and emphasizes the need to complete the study of fenofibrate in large randomized controlled clinical trials.Funding:Funding was provided by European Research Council Consolidator Grants OCLD (project no. 681870) and generous gifts from the Nikoh Foundation and the Sam and Rina Frankel Foundation (YN). The interventional study was supported by Abbott (project FENOC0003).Clinical trial number:NCT04661930.
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- 2023
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8. Cocirculation of A(H3N2) and B/Victoria increased morbidity in hospitalized patients in the 2019–2020 A(H1N1)pdm09 predominant influenza season in Israel
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Menucha Jurkowicz, Ital Nemet, Nofar Atari, Ilana S. Fratty, Limor Kliker, Hilda Sherbany, Nathan Keller, Eugene Leibovitz, Ella Mendelson, Michal Mandelboim, and Michal Stein
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Infectious Diseases ,Virology - Published
- 2023
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9. Author response: Efficacy and safety of metabolic interventions for the treatment of severe COVID-19: in vitro, observational, and non-randomized open-label interventional study
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Avner Ehrlich, Konstantinos Ioannidis, Makram Nasar, Ismaeel Abu Alkian, Yuval Daskal, Nofar Atari, Limor Kliker, Nir Rainy, Matan Hofree, Sigal Shafran Tikva, Inbal Houri, Arrigo Cicero, Chiara Pavanello, Cesare R Sirtori, Jordana B Cohen, Julio A Chirinos, Lisa Deutsch, Merav Cohen, Amichai Gottlieb, Adina Bar-Chaim, Oren Shibolet, Michal Mandelboim, Shlomo L Maayan, and Yaakov Nahmias
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- 2023
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10. Early Immunogenicity and Safety of the Third Dose of BNT162b2 Messenger RNA Coronavirus Disease 2019 Vaccine Among Adults Older Than 60 Years: Real-World Experience
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Ital Nemet, Gili Regev-Yochay, Victoria Indenbaum, Ella Mendelson, Yitshak Kreiss, Limor Kliker, Carmit Cohen, Erez Bar-Haim, Mayan Gilboa, Ram Doolman, Sharon Amit, Carmit Rubin, Galia Rahav, Hanaa Jaber, Yaniv Lustig, Keren Asraf, and Michal Mandelboim
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Male ,COVID-19 Vaccines ,Health Personnel ,T cell ,Antibodies, Viral ,Neutralization ,Immunogenicity, Vaccine ,Immune system ,medicine ,Humans ,Immunology and Allergy ,RNA, Messenger ,Neutralizing antibody ,BNT162 Vaccine ,Aged ,Aged, 80 and over ,Messenger RNA ,biology ,SARS-CoV-2 ,business.industry ,Immunogenicity ,Age Factors ,COVID-19 ,Middle Aged ,Antibodies, Neutralizing ,Titer ,Infectious Diseases ,medicine.anatomical_structure ,Immunoglobulin G ,Immunology ,biology.protein ,Female ,Antibody ,business - Abstract
Background Despite high vaccine coverage, an increase in breakthrough coronavirus disease 2019 (COVID-19) infections, prompted administration of a third BNT162b2 dose to people aged >60 years in Israel since July 2021. Here, we report real-world immunogenicity following third dose. Methods Overall, 208 healthcare workers aged >60 years were included. Paired pre– and post–second and/or third dose immunoglobulin G (IgG) and neutralizing antibody titers were compared. A subpopulation of low responders to the second dose was also tested for T-cell activation. For 25 paired serum samples, we tested neutralization of wild-type vs neutralization of Delta and Lambda variants, pre– and post–third dose. Active surveillance of vaccine adverse events was conducted through surveys. Results A pronounced immune response was observed following the third dose, including a 33-fold and 51-fold increase in IgG and neutralizing antibody, respectively. The neutralizing antibody levels post–third dose were 9.34 times higher than post–second dose (geometric mean titer, 2598 [95% confidence interval {CI}, 2085–3237] vs 207 [95% CI, 126–339]). Nine previously low responders had a significant antibody increase post–third dose, and 7 of 9 showed increase in T-cell activation. Additionally, sera obtained post–third dose highly and comparably neutralized the wild-type and Delta and Lambda variants. Of 1056 responders to the adverse-event survey, none had serious events. Conclusions We demonstrate a rapid and broad immune response to the third BNT162b2 dose in individuals >60 years of age.
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- 2021
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11. Omicron BA.2.75 variant is efficiently neutralised following BA.1 and BA.5 breakthrough infection in vaccinated individuals, Israel, June to September 2022
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Nofar, Atari, Limor, Kliker, Neta, Zuckerman, Bayan Abd, Elkader, Yael, Weiss-Ottolenghi, Ella, Mendelson, Yitshak, Kreiss, Gili, Regev-Yochay, and Michal, Mandelboim
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SARS-CoV-2 ,Epidemiology ,Virology ,Public Health, Environmental and Occupational Health ,Humans ,COVID-19 ,Israel ,Antibodies, Viral ,Antibodies, Neutralizing - Abstract
We evaluated neutralising antibody titres against wild type (WT) SARS-CoV-2 and four Omicron variants (BA.1, BA.2, BA.5 and BA.2.75) in fully vaccinated (three doses of Comirnaty vaccine) healthcare workers (HCW) in Israel who had breakthrough BA.1/BA5 infections. Omicron breakthrough infections in vaccinated individuals resulted in increased neutralising antibodies against the WT and Omicron variants compared with vaccinated uninfected HCW. HCW who recovered from BA.1 or BA.5 infections showed similar neutralising antibodies levels against BA.2.75.
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- 2022
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12. COVID-19 vaccination and BA.1 breakthrough infection induce neutralising antibodies which are less efficient against BA.4 and BA.5 Omicron variants, Israel, March to June 2022
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Limor, Kliker, Neta, Zuckerman, Nofar, Atari, Noam, Barda, Mayan, Gilboa, Ital, Nemet, Bayan, Abd Elkader, Ilana S, Fratty, Hanaa, Jaber, Ella, Mendelson, Sharon, Alroy-Preis, Yitshak, Kreiss, Gili, Regev-Yochay, and Michal, Mandelboim
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Vaccines ,COVID-19 Vaccines ,SARS-CoV-2 ,Epidemiology ,Virology ,Vaccination ,Public Health, Environmental and Occupational Health ,COVID-19 ,Humans ,Israel ,Antibodies, Viral ,Antibodies, Neutralizing - Abstract
This work evaluated neutralising antibody titres against wild type (WT) SARS-CoV-2 and four Omicron variants (BA.1, BA.2, BA.4 and BA.5) in healthcare workers who had breakthrough BA.1 infection. Omicron breakthrough infection in individuals vaccinated three or four times before infection resulted in increased neutralising antibodies against the WT virus. The fourth vaccine dose did not further improve the neutralising efficiency over the third dose against all Omicron variants, especially BA.4 and BA.5. An Omicron-specific vaccine may be indicated.
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- 2022
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13. Genome-wide CRISPR screens identify GATA6 as a proviral host factor for SARS-CoV-2 via modulation of ACE2
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Ma’ayan Israeli, Yaara Finkel, Yfat Yahalom-Ronen, Nir Paran, Theodor Chitlaru, Ofir Israeli, Inbar Cohen-Gihon, Moshe Aftalion, Reut Falach, Shahar Rotem, Uri Elia, Ital Nemet, Limor Kliker, Michal Mandelboim, Adi Beth-Din, Tomer Israely, Ofer Cohen, Noam Stern-Ginossar, and Adi Bercovich-Kinori
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Multidisciplinary ,Proviruses ,SARS-CoV-2 ,GATA6 Transcription Factor ,COVID-19 ,Humans ,General Physics and Astronomy ,Clustered Regularly Interspaced Short Palindromic Repeats ,Angiotensin-Converting Enzyme 2 ,General Chemistry ,Peptidyl-Dipeptidase A ,General Biochemistry, Genetics and Molecular Biology - Abstract
The global spread of SARS-CoV-2 led to major economic and health challenges worldwide. Revealing host genes essential for infection by multiple variants of SARS-CoV-2 can provide insights into the virus pathogenesis, and facilitate the development of novel therapeutics. Here, employing a genome-scale CRISPR screen, we provide a comprehensive data-set of cellular factors that are exploited by wild type SARS-CoV-2 as well as two additional recently emerged variants of concerns (VOCs), Alpha and Beta. We identified several host factors critical for SARS-CoV-2 infection, including various components belonging to the Clathrin-dependent transport pathway, ubiquitination, Heparan sulfate biogenesis and host phosphatidylglycerol biosynthesis. Comparative analysis of the different VOCs revealed the host factors KREMEN2 and SETDB1 as potential unique candidates required only to the Alpha variant. Furthermore, the analysis identified GATA6, a zinc finger transcription factor, as an essential proviral gene for all variants inspected. We show that GATA6 directly regulates ACE2 transcription and accordingly, is critical for SARS-CoV-2 cell entry. Analysis of clinical samples collected from SARS-CoV-2 infected individuals shows elevated levels of GATA6, suggesting a role in COVID-19 pathogenesis. Finally, pharmacological inhibition of GATA6 resulted in down-modulation of ACE2 and inhibition of viral infectivity. Overall, we show GATA6 may represent a target for the development of anti-SARS-CoV-2 therapeutic strategies and reaffirm the value of the CRISPR loss-of-function screens in providing a list of potential new targets for therapeutic interventions.
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- 2022
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14. The impact of SARS-CoV-2 on respiratory syndromic and sentinel surveillance in Israel, 2020: a new perspective on established systems
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Aharona, Glatman-Freedman, Lea, Gur-Arie, Hanna, Sefty, Zalman, Kaufman, Michal, Bromberg, Rita, Dichtiar, Alina, Rosenberg, Rakefet, Pando, Ital, Nemet, Limor, Kliker, Ella, Mendelson, Lital, Keinan-Boker, Neta S, Zuckerman, and Michal, Mandelboim
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SARS-CoV-2 ,COVID-19 ,Humans ,Israel ,Pandemics ,Sentinel Surveillance - Abstract
BackgroundThe COVID-19 pandemic presented new challenges for the existing respiratory surveillance systems, and adaptations were implemented. Systematic assessment of the syndromic and sentinel surveillance platforms during the pandemic is essential for understanding the value of each platform in the context of an emerging pathogen with rapid global spread.AimWe aimed to evaluate systematically the performance of various respiratory syndromic surveillance platforms and the sentinel surveillance system in Israel from 1 January to 31 December 2020.MethodsWe compared the 2020 syndromic surveillance trends to those of the previous 3 years, using Poisson regression adjusted for overdispersion. To assess the performance of the sentinel clinic system as compared with the national SARS-CoV-2 repository, a cubic spline with 7 knots and 95% confidence intervals were applied to the sentinel network's weekly percentage of positive SARS-CoV-2 cases.ResultsSyndromic surveillance trends changed substantially during 2020, with a statistically significant reduction in the rates of visits to physicians and emergency departments to below previous years' levels. Morbidity patterns of the syndromic surveillance platforms were inconsistent with the progress of the pandemic, while the sentinel surveillance platform was found to reflect the national circulation of SARS-CoV-2 in the population.ConclusionOur findings reveal the robustness of the sentinel clinics platform for the surveillance of the main respiratory viruses during the pandemic and possibly beyond. The robustness of the sentinel clinics platform during 2020 supports its use in locations with insufficient resources for widespread testing of respiratory viruses.
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- 2022
15. Efficacy of a Fourth Dose of Covid-19 mRNA Vaccine against Omicron
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Gili Regev-Yochay, Tal Gonen, Mayan Gilboa, Michal Mandelboim, Victoria Indenbaum, Sharon Amit, Lilac Meltzer, Keren Asraf, Carmit Cohen, Ronen Fluss, Asaf Biber, Ital Nemet, Limor Kliker, Gili Joseph, Ram Doolman, Ella Mendelson, Laurence S. Freedman, Dror Harats, Yitshak Kreiss, and Yaniv Lustig
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Vaccines, Synthetic ,COVID-19 Vaccines ,SARS-CoV-2 ,Immunization, Secondary ,COVID-19 ,Humans ,Vaccine Efficacy ,General Medicine ,mRNA Vaccines - Published
- 2022
16. 4th Dose COVID mRNA Vaccines’ Immunogenicity & Efficacy Against Omicron VOC
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Gili Regev-Yochay, Tal Gonen, Mayan Gilboa, Michal Mandelboim, Victoria Indenbaum, Sharon Amit, Lilac Meltzer, Keren Asraf, Carmit Cohen, Ronen Fluss, Asaf Biber, Ital Nemet, Limor Kliker, Gili Joseph, Ram Doolman, Ella Mendelson, Laurence S. Freedman, Dror Harats, Yitshak Kreiss, and Yaniv Lustig
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BACKGROUNDFollowing the emergence of the Omicron variant of concern, we investigated immunogenicity, efficacy and safety of BNT162b2 or mRNA1273 fourth dose in an open-label, clinical intervention trial.METHODSPrimary end-points were safety and immunogenicity and secondary end-points were vaccine efficacy in preventing SARS-CoV-2 infections and COVID-19 symptomatic disease. The two intervention arms were compared to a matched control group. Eligible participants were healthcare-workers (HCW) vaccinated with three BNT162b2 doses, and whose IgG antibody levels were ≤700 BAU (40-percentile). IgG and neutralizing titers, direct neutralization of live VOCs, and T-cell activation were assessed. All participants were actively screened for SARS-CoV-2 infections on a weekly basis.RESULTSOf 1050 eligible HCW, 154 and 120 were enrolled to receive BNT162b2 and mRNA1273, respectively, and compared to 426 age-matched controls. Recipients of both vaccine types had a ∼9-10-fold increase in IgG and neutralizing titers within 2 weeks of vaccination and an 8-fold increase in live Omicron VOC neutralization, restoring titers to those measured after the third vaccine dose. Breakthrough infections were common, mostly very mild, yet, with high viral loads. Vaccine efficacy against infection was 30% (95%CI:-9% to 55%) and 11% (95%CI:-43% to +43%) for BNT162b2 and mRNA1273, respectively. Local and systemic adverse reactions were reported in 80% and 40%, respectively.CONCLUSIONSThe fourth COVID-19 mRNA dose restores antibody titers to peak post-third dose titers. Low efficacy in preventing mild or asymptomatic Omicron infections and the infectious potential of breakthrough cases raise the urgency of next generation vaccine development.Trial registration numberclicaltrials.gov: NCT05231005, NCT05230953
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- 2022
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17. Third BNT162b2 Vaccination Neutralization of SARS-CoV-2 Omicron Infection
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Ital Nemet, Limor Kliker, Yaniv Lustig, Neta S. Zuckerman, Oran Erster, Carmit Cohen, Yitshak Kreiss, Sharon Alroy-Preis, Gili Regev-Yochay, Ella Mendelson, and Michal Mandelboim
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COVID-19 Vaccines ,SARS-CoV-2 ,Immunization, Secondary ,COVID-19 ,Humans ,Vaccine Efficacy ,General Medicine ,Antibodies, Neutralizing ,BNT162 Vaccine - Abstract
Using isolates of SARS-CoV-2 WT, Beta, Delta and most importantly Omicron we studied the capability of the BNT162b2 vaccine given in two or three doses to neutralize major SARS-CoV-2 variants of concern (VOC).We demonstrate low neutralization efficiency against delta and wild-type for vaccines with more than 5 months following the second BNT162b2 dose, with no neutralization efficiency against Omicron. We demonstrate the importance of a third dose, by showing a 100-fold increase in neutralization efficiency of Omicron following a third dose, with a 4-fold reduced neutralization compared to that against the Delta VOC. The durability of the effect of the third dose is yet to be determined.
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- 2021
18. High Immune Response Rate to the Fourth Boost of the BNT162b2 Vaccine against the Omicron Variants of Concern among Liver Transplant Recipients
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Yana Davidov, Victoria Indenbaum, Nofar Atari, Limor Kliker, Keren Tsaraf, Keren Asraf, Oranit Cohen-Ezra, Mariya Likhter, Orna Mor, Ram Doolman, Yael Weiss-Ottolenghi, Tammy Hod, Arnon Afek, Yitshak Kreiss, Yaniv Lustig, Gili Regev-Yochay, Michal Mandelboim, and Ziv Ben-Ari
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Infectious Diseases ,Virology ,BNT162b2 mRNA ,fourth dose ,liver transplant recipients ,breakthrough infection ,immune response ,side effects BNT162b2 mRNA vaccine - Abstract
The immune response of liver transplant (LT) recipients to a third dose of the BNT162b2 mRNA vaccine significantly waned after four months. We aimed to evaluate the immune response and breakthrough infection rates of a fourth dose against the Omicron variants among LT recipients. LT recipients who had no past or active SARS-CoV-2 infection and received three doses of the BNT162b2mRNA vaccine were included. Of the 73 LT recipients, 50 (68.5%) received a fourth dose. The fourth dose was associated with a significantly higher positive immune response than the third dose. Receptor-binding domain (RBD) IgG and Omicron BA.1 and BA.2 neutralizing antibodies were determined at a median of 132 and 29 days after the third and fourth vaccines. They were 345 binding antibody units per milliliter (BAU/mL) vs. 2118 BAU/mL (p < 0.0001), 10 vs. 87 (p < 0.0001), and 15 vs. 149 (p = 0.001), respectively. Breakthrough infections were documented among nine (18%) LT recipients after the fourth dose and among seven (30.4%) patients following the third dose (p = 0.2); 93.5% of breakthrough infections were mild. The infection rate after the fourth dose was higher among diabetic vs. nondiabetic recipients (33.3% vs. 6.9%, respectively; p = 0.02). Further studies are needed to evaluate additional factors influencing the breakthrough infection rate among LT recipients.
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- 2022
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19. Human metapneumovirus prevalence during 2019-2021 in Israel is influenced by the COVID-19 pandemic
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Michal Stein, Hodaya Cohen, Ital Nemet, Nofar Atari, Limor Kliker, Ilana S. Fratty, Efrat Bucris, Miranda Geva, Ella Mendelson, Neta Zuckerman, and Michal Mandelboim
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Microbiology (medical) ,Paramyxoviridae Infections ,Genotype ,COVID-19 ,Infant ,General Medicine ,Infectious Diseases ,Child, Preschool ,Prevalence ,Humans ,Metapneumovirus ,Israel ,Child ,Pandemics ,Respiratory Tract Infections ,Phylogeny - Abstract
To compare infection rates and circulating subtypes of human metapneumovirus (hMPV) before (2019-2020) and after the emergence of coronavirus disease 2019 (COVID-19) (2021) in Israel.In total, 12,718 respiratory samples were collected from hospitalized patients of all ages during the years 2019 to 2021 at the Sheba Medical Center in Israel and subjected to reverse transcription-polymerase chain reaction analysis. In addition, whole-genome sequencing was performed to characterize the subtypes of hMPV circulating in Israel between 2019 and 2021.A total of 481 samples were found positive for hMPV. Before the emergence of COVID-19, hMPV peaked in winter months and declined thereafter. In sharp contrast, during the COVID-19 pandemic, we observed a delayed peak in hMPV infection cases and higher infection of young children. Viral sequencing showed a shift in the most prevalent circulating hMPV strain from A2b to B1 during the years 2019, 2020, and 2021.Compared with the years before the COVID-19 pandemic, in 2021, hMPV mostly affected young children, and the most prevalent circulating subtype shifted from A2b in 2019 to B1.
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- 2021
20. Anti-human ACE2 antibody neutralizes and inhibits virus production of SARS-CoV-2 variants of concern
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Abigael E. Chaouat, Ilija Brizic, Paola Kucan Brlic, Nofar Atari, Limor Kliker, Or Alfi, Michal Mandelboim, Dana Wolf, Laith Tafish, Inbal Kol, Stipan Jonjic, and Ofer Mandelboim
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immunology ,virology ,Multidisciplinary ,BIOMEDICINE AND HEALTHCARE. Basic Medical Sciences ,Health sciences ,SARS-CoV-2 ,COVID-19 ,Virus neutralization ,Human angiotensin-converting enzyme-2 receptor (ACE2) ,Receptor binding domain (RBD) ,BIOMEDICINA I ZDRAVSTVO. Temeljne medicinske znanosti ,immune response - Abstract
The global pandemic caused by SARS-CoV-2 is a major public health problem. Vi- rus entry occurs via binding to ACE2. Five SARS- CoV-2 variants of concern (VOCs) were reported so far, all having immune escape characteristics. Infection with the current VOC Omicron was noticed in immunized and recovered individuals ; there- fore, the development of new treatments against VOC infections is urgently needed. Most approved mAbs treatments against SARS-CoV-2 are directed against the spike protein of the original virus and are therefore inefficient against Omicron. Here, we report on the generation of hACE2.16, an anti-ACE2 antibody that recognizes and blocks ACE2-RBD binding without affecting ACE2 enzymatic activity. We demonstrate that hACE2.16 binding to ACE2 does not affect its sur- face expression and that hACE2.16 blocks infection and virus production of various VOCs including Omicron BA.1 and BA.2. hACE2.16 might, therefore, be an efficient treatment against all VOCs, the current and probably also future ones.
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- 2022
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21. CRISPR screens for host factors critical for infection by SARS-CoV-2 variants of concern identify GATA6 as a central modulator of ACE2
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Ma’ayan Israeli, Yaara Finkel, Yfat Yahalom-Ronen, Nir Paran, Theodor Chitlaru, Ofir Israeli, Inbar Cohen-Gihon, Moshe Aftalion, Reut Falach, Uri Elia, Ital Nemet, Limor Kliker, Michal Mandelboim, Adi Beth-Din, Tomer Israely, Ofer Cohen, Noam Stern-Ginossar, and Adi Bercovich-Kinori
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Zinc finger transcription factor ,Infectivity ,GATA6 ,Transcription (biology) ,CRISPR ,Computational biology ,Biology ,Transport Pathway ,Gene ,Biogenesis - Abstract
The global spread of SARS-CoV-2 led to the most challenging pandemic in this century, posing major economic and health challenges worldwide. Revealing host genes essential for infection by multiple variants of SASR-CoV-2 can provide insights into the virus pathogenesis, and facilitates the development of novel broad-spectrum host-directed therapeutics. Here, employing genome-scale CRISPR screens, we provide a comprehensive data-set of cellular factors that are exploited by WT-SARS-CoV-2 as well as two additional recently emerged variants of concerns (VOCs), Alpha and Beta. These screens identified known and novel host factors critical for SARS-CoV-2 infection, including various components belonging to the Clathrin-dependent transport pathway, ubiquitination and Heparan sulfate biogenesis. In addition, the host phosphatidylglycerol biosynthesis processes appeared to have major anti-viral functions. Comparative analysis of the different VOCs revealed the host factors KREMEN2 and SETDB1 as potential unique candidates required only to the Alpha variant, providing a possible explanation for the increased infectivity of this variant. Furthermore, the analysis identified GATA6, a zinc finger transcription factor, as an essential pro-viral gene for all variants inspected. We revealed that GATA6 directly regulates ACE2 transcription and accordingly, is critical for SARS-CoV-2 cell entry. Analysis of clinical samples collected from SARS-CoV-2 infected individuals showed an elevated level of GATA6, indicating the important role GATA6 may be playing in COVID-19 pathogenesis. Finally, pharmacological inhibition of GATA6 resulted in down-modulation of ACE2 and consequently to inhibition of the viral infectivity. Overall, we show GATA6 represents a target for the development of anti-SARS-CoV-2 therapeutic strategies and reaffirm the value of the CRISPR loss-of-function screens in providing a list of potential new targets for therapeutic interventions.
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- 2021
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22. The Rise and Fall of a Local SARS-CoV-2 Variant with the Spike Protein Mutation L452R
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Dana Bar-Ilan, Michal Linial, Neta S. Zuckerman, Limor Kliker, Ital Nemet, Ella Mendelson, Shay Fleishon, Orna Mor, Efrat Bucris, Yaniv Lustig, and Michal Mandelboim
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Pharmacology ,Lineage (genetic) ,SARS-CoV-2 ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Immunology ,Outbreak ,variant ,mutation ,sequencing ,neutralization ,Disease ,Biology ,Virology ,Neutralization ,Article ,Vaccination ,Infectious Diseases ,Drug Discovery ,Mutation (genetic algorithm) ,Medicine ,Pharmacology (medical) ,Dominance (genetics) - Abstract
Emerging SARS-CoV-2 variants may threaten global vaccination efforts and the awaited reduction in outbreak burden. In this study, we report a novel variant carrying the L452R mutation that emerged from a local B.1.362 lineage, B.1.362+L452R. The L452R mutation is associated with the Delta and Epsilon variants and was shown to cause increased infection and reduction in neutralization in pseudoviruses. Indeed, the B.1.362+L452R variant demonstrated a X4-fold reduction in neutralization capacity of sera from BNT162b2-vaccinated individuals compared to a wild-type strain. The variant infected 270 individuals in Israel between December 2020 and March 2021, until diminishing due to the gain in dominance of the Alpha variant in February 2021. This study demonstrates an independent, local emergence of a variant carrying a critical mutation, L452R, which may have the potential of becoming a variant of concern and emphasizes the importance of routine surveillance and detection of novel variants among efforts undertaken to prevent further disease spread.
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- 2021
23. Favorable outcome on viral load and culture viability using Ivermectin in early treatment of non-hospitalized patients with mild COVID-19 – A double-blind, randomized placebo-controlled trial
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Ital Nemet, Amit Shaham, Eli Schwartz, Michal Mandelboim, Asaf Biber, Limor Kliker, Oran Erster, Geva Harmelin, Li Ram, and Dana Lev
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medicine.medical_specialty ,Coronavirus disease 2019 (COVID-19) ,business.industry ,Viral culture ,Placebo-controlled study ,Placebo ,Gastroenterology ,Asymptomatic ,Ivermectin ,Internal medicine ,Clinical endpoint ,Medicine ,medicine.symptom ,business ,Viral load ,medicine.drug - Abstract
BackgroundIvermectin, an anti-parasitic agent, also has anti-viral properties. Our aim was to assess whether ivermectin can shorten the viral shedding in patients at an early-stage of COVID-19 infection.MethodsThe double-blinded trial compared patients receiving ivermectin 0·2 mg/kg for 3 days vs. placebo in non-hospitalized COVID-19 patients. RT-PCR from a nasopharyngeal swab was obtained at recruitment and then every two days. Primary endpoint was reduction of viral-load on the 6th day (third day after termination of treatment) as reflected by Ct level>30 (non-infectious level). The primary outcome was supported by determination of viral culture viability.ResultsEighty-nine patients were eligible (47 in ivermectin and 42 in placebo arm). Their median age was 35 years. Females accounted for 21·6%, and 16·8% were asymptomatic at recruitment. Median time from symptom onset was 4 days. There were no statistical differences in these parameters between the two groups.On day 6, 34 out of 47 (72%) patients in the ivermectin arm reached the endpoint, compared to 21/ 42 (50%) in the placebo arm (OR 2·62; 95% CI: 1·09-6·31). In a multivariable logistic-regression model, the odds of a negative test at day 6 was 2.62 time higher in the ivermectin group (95% CI: 1·06–6·45). Cultures at days 2 to 6 were positive in 3/23 (13·0%) of ivermectin samples vs. 14/29 (48·2%) in the placebo group (p=0·008).ConclusionsThere were significantly lower viral loads and viable cultures in the ivermectin group, which could lead to shortening isolation time in these patients.The study is registered at ClinicalTrials.gov NCT 044297411.
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- 2021
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24. The neutralization potency of anti-SARS-CoV-2 therapeutic human monoclonal antibodies is retained against novel viral variants
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Efi Makdasi, Anat Zvi, Ron Alcalay, Tal Noy-Porat, Eldar Peretz, Adva Mechaly, Yinon Levy, Eyal Epstein, Theodor Chitlaru, Ariel Tennenhouse, Moshe Aftalion, David Gur, Nir Paran, Hadas Tamir, Oren Zimhony, Shay Weiss, Michal Mandelboim, Ella Mendelson, Neta Zuckerman, Ital Nemet, Limor Kliker, Shmuel Yitzhaki, Shmuel C. Shapira, Tomer Israely, Sarel J. Fleishman, Ohad Mazor, and Ronit Rosenfeld
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chemistry.chemical_classification ,medicine.drug_class ,Biology ,Monoclonal antibody ,Virology ,Epitope ,Virus ,Neutralization ,In vitro ,chemistry ,medicine ,biology.protein ,Potency ,Antibody ,Glycoprotein - Abstract
SummaryA wide range of SARS-CoV-2 neutralizing monoclonal antibodies (mAbs) were reported to date, most of which target the spike glycoprotein and in particular its receptor binding domain (RBD) and N-terminal domain (NTD) of the S1 subunit. The therapeutic implementation of these antibodies has been recently challenged by emerging SARS-CoV-2 variants that harbor extensively mutated spike versions. Consequently, the re-assessment of mAbs, previously reported to neutralize the original early-version of the virus, is of high priority.Four previously selected mAbs targeting non-overlapping epitopes, were evaluated for their binding potency to RBD versions harboring individual mutations at spike positions 417, 439, 453, 477, 484 and 501. Mutations at these positions represent the prevailing worldwide distributed modifications of the RBD, previously reported to mediate escape from antibody neutralization. Additionally, the in vitro neutralization potencies of the four RBD-specific mAbs, as well as two NTD-specific mAbs, were evaluated against two frequent SARS-CoV-2 variants of concern (VOCs): (i) the B.1.1.7 variant, emerged in the UK and (ii) the B.1.351 variant, emerged in South Africa. Variant B.1.351 was previously suggested to escape many therapeutic mAbs, including those authorized for clinical use. The possible impact of RBD mutations on recognition by mAbs is addressed by comparative structural modelling. Finally, we demonstrate the therapeutic potential of three selected mAbs by treatment of K18-hACE2 transgenic mice two days post infection with each of the virus strains.Our results clearly indicate that despite the accumulation of spike mutations, some neutralizing mAbs preserve their potency against SARS-CoV-2. In particular, the highly potent MD65 and BL6 mAbs are shown to retain their ability to bind the prevalent novel viral mutations and to effectively protect against B.1.1.7 and B.1.351 variants of high clinical concern.
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- 2021
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25. Neutralizing Response against Variants after SARS-CoV-2 Infection and One Dose of BNT162b2
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Michal Mandelboim, Ella Mendelson, Limor Kliker, Yaniv Lustig, Sharon Alroy-Preis, Ital Nemet, Ruti Yishai, and Neta S. Zuckerman
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2019-20 coronavirus outbreak ,COVID-19 Vaccines ,Coronavirus disease 2019 (COVID-19) ,viruses ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,030204 cardiovascular system & hematology ,Antibodies, Viral ,Virus ,03 medical and health sciences ,0302 clinical medicine ,Neutralization Tests ,Correspondence ,Humans ,Medicine ,030212 general & internal medicine ,skin and connective tissue diseases ,BNT162 Vaccine ,biology ,SARS-CoV-2 ,business.industry ,fungi ,COVID-19 ,General Medicine ,Antibodies, Neutralizing ,Virology ,respiratory tract diseases ,body regions ,Vaccination ,biology.protein ,Antibody ,business - Abstract
Vaccination after SARS-CoV-2 Infection Six patients previously infected with the original SARS-CoV-2 virus received the BNT162b2 vaccine. Before vaccination, they had neutralizing activity against ...
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- 2021
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