226 results on '"Ben-Shmuel, A"'
Search Results
2. Short- and long-term outcomes of pulmonary exposure to a sublethal dose of ricin in mice
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Anita Sapoznikov, Yentl Evgy, Amir Ben-Shmuel, Arieh Schwartz, Ron Alcalay, Moshe Aftalion, Alon Ben David, Noam Erez, and Reut Falach
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Medicine ,Science - Abstract
Abstract Ricin, an extremely potent toxin produced from the seeds of castor plant, Ricinus communis, is ribosome-inactivating protein that blocks cell-protein synthesis. It is considered a biological threat due to worldwide availability of castor beans, massive quantities as a by-product of castor oil production, high stability and ease of production. The consequence of exposure to lethal dose of ricin was extensively described in various animal models. However, it is assumed that in case of aerosolized ricin bioterror attack, the majority of individuals would be exposed to sublethal doses rather than to lethal ones. Therefore, the purpose of current study was to assess short- and long-term effects on physiological parameters and function following sublethal pulmonary exposure. We show that in the short-term, sublethal exposure of mice to ricin resulted in acute lung injury, including interstitial pneumonia, cytokine storm, neutrophil influx, edema and cellular death. This damage was manifested in reduced lung performance and physiological function. Interestingly, although in the long-term, mice recovered from acute lung damage and restored pulmonary and physiological functionality, the reparative process was associated with lasting fibrotic lesions. Therefore, restriction of short-term acute phase of the disease and management of long-term pulmonary fibrosis by medical countermeasures is expected to facilitate the quality of life of exposed survivors.
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- 2024
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3. The Gendered Language of Financial Advice: Finfluencers, Framing, and Subconscious Preferences
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Ambreen Tour Ben-Shmuel, Adam Hayes, and Vanessa Drach
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Social Sciences ,Sociology (General) ,HM401-1281 - Abstract
As financial advice migrates online, “finfluencers” are democratizing access to financial knowledge, challenging the historically male-dominated advisory landscape. This mixed-methods study explores how gender shapes the creation and consumption of finfluencer content. Qualitative analysis reveals gendered advice patterns: Men emphasize quantitative aspects, whereas women incorporate narratives and personal stories. Experimental surveys uncover subconscious same-gender preferences in advice receptivity, contrasting with stated desires for gender-neutral guidance. These implicit affinities persist even when advice content is anonymized and gender-balanced. Paradoxically, finfluencers introduce diverse voices and challenge traditional norms yet also subtly cater to gendered perspectives. The research highlights the complex role of gender in the digital financial advice market, where expanding inclusivity coexists with enduring biases. Findings offer insights for developing more equitable and empowering financial education in the digital age while revealing the subconscious factors shaping the emerging finfluencer discourse.
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- 2024
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4. Pediatricians’ confidence level in diagnosing and treating children with atopic dermatitis in Israel, based on a self-efficacy survey
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Golan-Tripto, Inbal, Ben Shmuel, Atar, Muallem, Liezl, Yahav, Lior, Andre, Nicolas, Shaki, David, and Horev, Amir
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- 2023
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5. Induction of Superior Systemic and Mucosal Protective Immunity to SARS-CoV-2 by Nasal Administration of a VSV–ΔG–Spike Vaccine
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Yfat Yahalom-Ronen, Sharon Melamed, Boaz Politi, Noam Erez, Hadas Tamir, Liat Bar-On, Julia Ryvkin, Dena Leshkowitz, Ofir Israeli, Shay Weiss, Amir Ben-Shmuel, Moria Barlev-Gross, Lilach Cherry Mimran, Hagit Achdout, Nir Paran, and Tomer Israely
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SARS-CoV-2 ,vaccine ,nasal vaccination ,immunity ,VSV–∆G–spike ,mucosal vaccination ,Medicine - Abstract
The emergence of rapidly spreading variants of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) poses a major challenge to vaccines’ protective efficacy. Intramuscular (IM) vaccine administration induces short-lived immunity but does not prevent infection and transmission. New vaccination strategies are needed to extend the longevity of vaccine protection, induce mucosal and systemic immunity and prevent viral transmission. The intranasal (IN) administration of the VSV–ΔG–spike vaccine candidate directly to mucosal surfaces yielded superior mucosal and systemic immunity at lower vaccine doses. Compared to IM vaccination in the K18–hACE2 model, IN vaccination preferentially induced mucosal IgA and T-cells, reduced the viral load at the site of infection, and ameliorated disease-associated brain gene expression. IN vaccination was protective even one year after administration. As most of the world population has been vaccinated by IM injection, we demonstrate the potential of a heterologous IM + IN vaccination regimen to induce mucosal immunity while maintaining systemic immunity. Furthermore, the IM + IN regimen prevented virus transmission in a golden Syrian hamster co-caging model. Taken together, we show that IN vaccination with VSV–ΔG–spike, either as a homologous IN + IN regimen or as a boost following IM vaccination, has a favorable potential over IM vaccination in inducing efficient mucosal immunity, long-term protection and preventing virus transmission.
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- 2024
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6. Hybrid PANI-halamine design, synthesis and antibacterial activity
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Weiss, Shay, Ben-Shmuel, Amir, Chajanovsky, Itamar, Mizrahi, Dana M., and Suckeveriene, Ran Yosef
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- 2023
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7. Israeli pediatricians’ confidence level in diagnosing and treating children with skin disorders: a cross-sectional questionnaire pilot study
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Nicolas Andre, Liezl Muallem, Lior Yahav, Inbal Golan-Tripto, Atar Ben Shmuel, and Amir Horev
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dermatology ,medical education ,pediatrics ,residency ,self-efficacy ,Medicine (General) ,R5-920 - Abstract
BackgroundPediatricians daily see large numbers of patients with skin disorders. However, they encounter limited guidance as a result of a marked deficiency in pediatric dermatologists. Hence, reevaluation of training opportunities during pediatric residency has become essential. Our aim was to evaluate the confidence level of pediatric residents and specialists in diagnosing and treating skin disorders in children and to determine career and training-related characteristics that influence it.MethodsConducted as a cross-sectional study, we administered a questionnaire to 171 pediatricians across Israel. We assessed respondents’ self-efficacy about their ability to diagnose and treat skin disorders and collected data regarding their previous dermatology training and preferred training methods.Results77.8% of respondents reported below or average self-efficacy scores in diagnosing and managing children with skin disorders. Older age (>40 years old; OR = 5.51, p = 0.019), treating a higher number of patients with skin disorders (OR = 2.96, p = 0.032), and having any training in dermatology, either during medical school or residency (OR = 7.16, p = 0.031, OR = 11.14, p = 0.003 respectively), were all significant parameters involved in pediatricians reporting high self-efficacy in skin disorder management.ConclusionMost pediatric residents and pediatricians have average or below-average confidence in managing pediatric skin disorders. We suggest incorporating dermatology rotations during pediatric residency to improve young pediatricians’ self-efficacy in managing skin disorders and ultimately help pediatricians provide better care for patients presenting with dermatological conditions. These findings can ultimately help refine a pilot program in dermatology that might be implemented during pediatric residency.
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- 2023
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8. BRCA mutational status shapes the stromal microenvironment of pancreatic cancer linking clusterin expression in cancer associated fibroblasts with HSF1 signaling
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Lee Shaashua, Aviad Ben-Shmuel, Meirav Pevsner-Fischer, Gil Friedman, Oshrat Levi-Galibov, Subhiksha Nandakumar, Debra Barki, Reinat Nevo, Lauren E. Brown, Wenhan Zhang, Yaniv Stein, Chen Lior, Han Sang Kim, Linda Bojmar, William R. Jarnagin, Nicolas Lecomte, Shimrit Mayer, Roni Stok, Hend Bishara, Rawand Hamodi, Ephrat Levy-Lahad, Talia Golan, John A. Porco, Christine A. Iacobuzio-Donahue, Nikolaus Schultz, David A. Tuveson, David Lyden, David Kelsen, and Ruth Scherz-Shouval
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Science - Abstract
Cancer-associated fibroblasts are transcriptionally rewired by signals from the cancer cells, resulting in heterogeneous populations. Here the authors show that loss of BRCA function in pancreatic cancer cells leads to HSF1–dependent accumulation of immune-regulatory clusterin-positive cancer associated fibroblasts.
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- 2022
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9. Cancer-associated fibroblasts in the single-cell era
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Lavie, Dor, Ben-Shmuel, Aviad, Erez, Neta, and Scherz-Shouval, Ruth
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- 2022
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10. Development of an immunofluorescence assay for detection of SARS-CoV-2
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Atiya-Nasagi, Yafit, Milrot, Elad, Makdasi, Efi, Schuster, Ofir, Shmaya, Shlomo, Simon, Irit, Ben-Shmuel, Amir, Beth-Din, Adi, Weiss, Shay, and Laskar, Orly
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- 2022
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11. Alternate atxA and acpA dependent response of Bacillus anthracis to serum, HCO3- and CO2
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Itai Glinert, Elad Bar-David, Amir Ben-Shmuel, Assa Sittner, Reut Puni, Shira Laredo, David Kobiler, Shay Weiss, and Haim Levy
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Medicine ,Science - Abstract
Bacillus anthracis overcomes host immune responses by producing capsule and secreting toxins. Production of these virulence factors in response to entering the host environment was shown to be regulated by atxA, the major virulence regulator, known to be activated by HCO3- and CO2. While toxin production is regulated directly by atxA, capsule production is independently mediated by two regulators; acpA and acpB. In addition, it was demonstrated that acpA has at least two promotors, one of them shared with atxA. We used a genetic approach to study capsule and toxin production under different conditions. Unlike previous works utilizing NBY, CA or R-HCO3- medium under CO2 enriched conditions, we used a sDMEM-based medium. Thus, toxin and capsule production can be induced in ambient or CO2 enriched atmosphere. Using this system, we could differentiate between induction by 10% NRS, 10% CO2 or 0.75% HCO3-. In response to high CO2, capsule production is induced by acpA based response in an atxA-independent manner, with little to no toxin (protective antigen PA) production. atxA based response is activated in response to serum independently of CO2, inducing toxin and capsule production in an acpA or acpB dependent manner. HCO3- was also found to activate atxA based response, but in non-physiological concentrations. Our findings may help explain the first stages of inhalational infection, in which spores germinating in dendritic cells require protection (by encapsulation) without affecting cell migration to the draining lymph-node by toxin secretion.
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- 2023
12. Preliminary nonclinical safety and immunogenicity of an rVSV-ΔG-SARS-CoV-2-S vaccine in mice, hamsters, rabbits and pigs
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Madar-Balakirski, Noa, Rosner, Amir, Melamed, Sharon, Politi, Boaz, Steiner, Michal, Tamir, Hadas, Yahalom-Ronen, Yfat, Bar-David, Elad, Ben-Shmuel, Amir, Sittner, Assa, Glinert, Itai, Weiss, Shay, Bar-Haim, Erez, Cohen, Hila, Elia, Uri, Achdout, Hagit, Erez, Noam, Rotem, Shahar, Lazar, Shlomi, Nyska, Abraham, Yitzhaki, Shmuel, Beth-Din, Adi, Levy, Haim, Paran, Nir, Israely, Tomer, and Marcus, Hadar
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- 2022
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13. Coupling immuno-magnetic capture with LC–MS/MS(MRM) as a sensitive, reliable, and specific assay for SARS-CoV-2 identification from clinical samples
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Schuster, Ofir, Atiya-Nasagi, Yafit, Rosen, Osnat, Zvi, Anat, Glinert, Itai, Ben Shmuel, Amir, Weiss, Shay, Laskar, Orly, and Feldberg, Liron
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- 2022
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14. BRCA mutational status shapes the stromal microenvironment of pancreatic cancer linking clusterin expression in cancer associated fibroblasts with HSF1 signaling
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Shaashua, Lee, Ben-Shmuel, Aviad, Pevsner-Fischer, Meirav, Friedman, Gil, Levi-Galibov, Oshrat, Nandakumar, Subhiksha, Barki, Debra, Nevo, Reinat, Brown, Lauren E., Zhang, Wenhan, Stein, Yaniv, Lior, Chen, Kim, Han Sang, Bojmar, Linda, Jarnagin, William R., Lecomte, Nicolas, Mayer, Shimrit, Stok, Roni, Bishara, Hend, Hamodi, Rawand, Levy-Lahad, Ephrat, Golan, Talia, Porco, Jr., John A., Iacobuzio-Donahue, Christine A., Schultz, Nikolaus, Tuveson, David A., Lyden, David, Kelsen, David, and Scherz-Shouval, Ruth
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- 2022
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15. LAMP-Seq enables sensitive, multiplexed COVID-19 diagnostics using molecular barcoding
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Ludwig, Kerstin U., Schmithausen, Ricarda M., Li, David, Jacobs, Max L., Hollstein, Ronja, Blumenstock, Katja, Liebing, Jana, Słabicki, Mikołaj, Ben-Shmuel, Amir, Israeli, Ofir, Weiss, Shay, Ebert, Thomas S., Paran, Nir, Rüdiger, Wibke, Wilbring, Gero, Feldman, David, Lippke, Bärbel, Ishorst, Nina, Hochfeld, Lara M., Beins, Eva C., Kaltheuner, Ines H., Schmitz, Maximilian, Wöhler, Aliona, Döhla, Manuel, Sib, Esther, Jentzsch, Marius, Borrajo, Jacob D., Strecker, Jonathan, Reinhardt, Julia, Cleary, Brian, Geyer, Matthias, Hölzel, Michael, Macrae, Rhiannon, Nöthen, Markus M., Hoffmann, Per, Exner, Martin, Regev, Aviv, Zhang, Feng, and Schmid-Burgk, Jonathan L.
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- 2021
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16. Revisiting SARS-CoV-2 environmental contamination by patients with COVID-19: The Omicron variant does not differ from previous strains
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Itai Glinert, Amir Ben-Shmuel, Moran Szwartcwort-Cohen, Adi Beth-din, Orly Laskar, Moria Barlev-Gross, Sharon Melamed, Noga Arbell, Haim Levy, Netanel A Horowitz, and Shay Weiss
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SARS-CoV-2 ,Omicron ,Alpha ,original ,surface contamination ,air samples ,Infectious and parasitic diseases ,RC109-216 - Abstract
SARS-CoV-2 Omicron strain emergence raised concerns that its enhanced infectivity is partly due to altered spread/contamination modalities. We therefore sampled high-contact surfaces and air in close proximity to patients who were verified as infected with the Omicron strain, using identical protocols applied to sample patients positive to the original or Alpha strains. Cumulatively, for all 3 strains, viral RNA was detected in 90 of 168 surfaces and 6 of 49 air samples (mean cycle threshold [Ct]=35.2±2.5). No infective virus was identified. No significant differences in prevalence were found between strains.
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- 2022
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17. Targeting the actin nucleation promoting factor WASp provides a therapeutic approach for hematopoietic malignancies
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Guy Biber, Aviad Ben-Shmuel, Elad Noy, Noah Joseph, Abhishek Puthenveetil, Neria Reiss, Omer Levy, Itay Lazar, Ariel Feiglin, Yanay Ofran, Meirav Kedmi, Abraham Avigdor, Sophia Fried, and Mira Barda-Saad
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Science - Abstract
Cancer cells proliferate and invade via cytoskeletal proteins such as WASp, exclusively expressed in hematopoietic cells. Here the authors show a specific small molecule compound inhibiting cancer cell activity by WASp degradation and demonstrating its therapeutic potential in vitro and in vivo.
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- 2021
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18. In Vitro and In Vivo Therapeutic Potential of 6,6′-Dihydroxythiobinupharidine (DTBN) from Nuphar lutea on Cells and K18-hACE2 Mice Infected with SARS-CoV-2
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Shay Weiss, Kamran Waidha, Saravanakumar Rajendran, Daniel Benharroch, Jannat Khalilia, Haim Levy, Elad Bar-David, Avi Golan-Goldhirsh, Jacob Gopas, and Amir Ben-Shmuel
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SARS-CoV-2 ,COVID-19 ,6,6′-dihydroxythiobinupharidine (DTBN) ,RNA-dependent RNA polymerase (RdRp) ,anti-viral small molecule drug ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
We have previously published research on the anti-viral properties of an alkaloid mixture extracted from Nuphar lutea, the major components of the partially purified mixture found by NMR analysis. These are mostly dimeric sesquiterpene thioalkaloids called thiobinupharidines and thiobinuphlutidines against the negative strand RNA measles virus (MV). We have previously reported that this extract inhibits the MV as well as its ability to downregulate several MV proteins in persistently MV-infected cells, especially the P (phospho)-protein. Based on our observation that the Nuphar extract is effective in vitro against the MV, and the immediate need that the coronavirus disease 2019 (COVID-19) pandemic created, we tested here the ability of 6,6′-dihydroxythiobinupharidine DTBN, an active small molecule, isolated from the Nuphar lutea extract, on COVID-19. As shown here, DTBN effectively inhibits SARS-CoV-2 production in Vero E6 cells at non-cytotoxic concentrations. The short-term daily administration of DTBN to infected mice delayed the occurrence of severe clinical outcomes, lowered virus levels in the lungs and improved survival with minimal changes in lung histology. The viral load on lungs was significantly reduced in the treated mice. DTBN is a pleiotropic small molecule with multiple targets. Its anti-inflammatory properties affect a variety of pathogens including SARS-CoV-2 as shown here. Its activity appears to target both pathogen specific (as suggested by docking analysis) as well as cellular proteins, such as NF-κB, PKCs, cathepsins and topoisomerase 2, that we have previously identified in our work. Thus, this combined double action of virus inhibition and anti-inflammatory activity may enhance the overall effectivity of DTBN. The promising results from this proof-of-concept in vitro and in vivo preclinical study should encourage future studies to optimize the use of DTBN and/or its molecular derivatives against this and other related viruses.
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- 2023
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19. Spike vs nucleocapsid SARS-CoV-2 antigen detection: application in nasopharyngeal swab specimens
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Barlev-Gross, Moria, Weiss, Shay, Ben-Shmuel, Amir, Sittner, Assa, Eden, Keren, Mazuz, Noam, Glinert, Itai, Bar-David, Elad, Puni, Reut, Amit, Sharon, Kriger, Or, Schuster, Ofir, Alcalay, Ron, Makdasi, Efi, Epstein, Eyal, Noy-Porat, Tal, Rosenfeld, Ronit, Achdout, Hagit, Mazor, Ohad, Israely, Tomer, Levy, Haim, and Mechaly, Adva
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- 2021
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20. Specific and Rapid SARS-CoV‑2 Identification Based on LC-MS/MS Analysis
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Ofir Schuster, Anat Zvi, Osnat Rosen, Hagit Achdout, Amir Ben-Shmuel, Ohad Shifman, Shmuel Yitzhaki, Orly Laskar, and Liron Feldberg
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Chemistry ,QD1-999 - Published
- 2021
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21. Detection and infectivity potential of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) environmental contamination in isolation units and quarantine facilities
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Ben-Shmuel, Amir, Brosh-Nissimov, Tal, Glinert, Itai, Bar-David, Elad, Sittner, Assa, Poni, Reut, Cohen, Regev, Achdout, Hagit, Tamir, Hadas, Yahalom-Ronen, Yfat, Politi, Boaz, Melamed, Sharon, Vitner, Einat, Cherry, Lilach, Israeli, Ofir, Beth-Din, Adi, Paran, Nir, Israely, Tomer, Yitzhaki, Shmuel, Levy, Haim, and Weiss, Shay
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- 2020
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22. Induction of Superior Systemic and Mucosal Protective Immunity to SARS-CoV-2 by Nasal Administration of a VSV–ΔG–Spike Vaccine.
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Yahalom-Ronen, Yfat, Melamed, Sharon, Politi, Boaz, Erez, Noam, Tamir, Hadas, Bar-On, Liat, Ryvkin, Julia, Leshkowitz, Dena, Israeli, Ofir, Weiss, Shay, Ben-Shmuel, Amir, Barlev-Gross, Moria, Cherry Mimran, Lilach, Achdout, Hagit, Paran, Nir, and Israely, Tomer
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SARS-CoV-2 ,INTRANASAL administration - Abstract
The emergence of rapidly spreading variants of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) poses a major challenge to vaccines' protective efficacy. Intramuscular (IM) vaccine administration induces short-lived immunity but does not prevent infection and transmission. New vaccination strategies are needed to extend the longevity of vaccine protection, induce mucosal and systemic immunity and prevent viral transmission. The intranasal (IN) administration of the VSV–ΔG–spike vaccine candidate directly to mucosal surfaces yielded superior mucosal and systemic immunity at lower vaccine doses. Compared to IM vaccination in the K18–hACE2 model, IN vaccination preferentially induced mucosal IgA and T-cells, reduced the viral load at the site of infection, and ameliorated disease-associated brain gene expression. IN vaccination was protective even one year after administration. As most of the world population has been vaccinated by IM injection, we demonstrate the potential of a heterologous IM + IN vaccination regimen to induce mucosal immunity while maintaining systemic immunity. Furthermore, the IM + IN regimen prevented virus transmission in a golden Syrian hamster co-caging model. Taken together, we show that IN vaccination with VSV–ΔG–spike, either as a homologous IN + IN regimen or as a boost following IM vaccination, has a favorable potential over IM vaccination in inducing efficient mucosal immunity, long-term protection and preventing virus transmission. [ABSTRACT FROM AUTHOR]
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- 2024
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23. A single dose of recombinant VSV-∆G-spike vaccine provides protection against SARS-CoV-2 challenge
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Yfat Yahalom-Ronen, Hadas Tamir, Sharon Melamed, Boaz Politi, Ohad Shifman, Hagit Achdout, Einat B. Vitner, Ofir Israeli, Elad Milrot, Dana Stein, Inbar Cohen-Gihon, Shlomi Lazar, Hila Gutman, Itai Glinert, Lilach Cherry, Yaron Vagima, Shirley Lazar, Shay Weiss, Amir Ben-Shmuel, Roy Avraham, Reut Puni, Edith Lupu, Elad Bar-David, Assa Sittner, Noam Erez, Ran Zichel, Emanuelle Mamroud, Ohad Mazor, Haim Levy, Orly Laskar, Shmuel Yitzhaki, Shmuel C. Shapira, Anat Zvi, Adi Beth-Din, Nir Paran, and Tomer Israely
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Science - Abstract
Here, the authors generate a replication-competent VSV based vaccine expressing SARS-CoV-2 spike protein and show protection in the hamster model with one dose. Analysis of the antibody response in mice shows induction of neutralizing antibodies and suggests a desirable Th1-biased response to the vaccine.
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- 2020
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24. Inhibition of SHP-1 activity by PKC-θ regulates NK cell activation threshold and cytotoxicity
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Aviad Ben-Shmuel, Batel Sabag, Abhishek Puthenveetil, Guy Biber, Moria Levy, Tammir Jubany, Fatima Awwad, Roshan Kumar Roy, Noah Joseph, Omri Matalon, Jessica Kivelevitz, and Mira Barda-Saad
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PKC ,natural killer ,SHP-1 ,signaling ,cancer ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
Natural killer (NK) cells play a crucial role in immunity, killing virally infected and cancerous cells. The balance of signals initiated upon engagement of activating and inhibitory NK receptors with cognate ligands determines killing or tolerance. Nevertheless, the molecular mechanisms regulating rapid NK cell discrimination between healthy and malignant cells in a heterogeneous tissue environment are incompletely understood. The SHP-1 tyrosine phosphatase is the central negative NK cell regulator that dephosphorylates key activating signaling proteins. Though the mechanism by which SHP-1 mediates NK cell inhibition has been partially elucidated, the pathways by which SHP-1 is itself regulated remain unclear. Here, we show that phosphorylation of SHP-1 in NK cells on the S591 residue by PKC-θ promotes the inhibited SHP-1 ‘folded’ state. Silencing PKC-θ maintains SHP-1 in the active conformation, reduces NK cell activation and cytotoxicity, and promotes tumor progression in vivo. This study reveals a molecular pathway that sustains the NK cell activation threshold through suppression of SHP-1 activity.
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- 2022
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25. Modulation of intrinsic inhibitory checkpoints using nano‐carriers to unleash NK cell activity
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Guy Biber, Batel Sabag, Anat Raiff, Aviad Ben‐Shmuel, Abhishek Puthenveetil, Jennifer I C Benichou, Tammir Jubany, Moria Levy, Shiran Killner, and Mira Barda‐Saad
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Cbl ,immunotherapy ,nanoparticles ,NK cells ,SHP‐1 ,Medicine (General) ,R5-920 ,Genetics ,QH426-470 - Abstract
Abstract Natural killer (NK) cells provide a powerful weapon mediating immune defense against viral infections, tumor growth, and metastatic spread. NK cells demonstrate great potential for cancer immunotherapy; they can rapidly and directly kill cancer cells in the absence of MHC‐dependent antigen presentation and can initiate a robust immune response in the tumor microenvironment (TME). Nevertheless, current NK cell‐based immunotherapies have several drawbacks, such as the requirement for ex vivo expansion of modified NK cells, and low transduction efficiency. Furthermore, to date, no clinical trial has demonstrated a significant benefit for NK‐based therapies in patients with advanced solid tumors, mainly due to the suppressive TME. To overcome current obstacles in NK cell‐based immunotherapies, we describe here a non‐viral lipid nanoparticle‐based delivery system that encapsulates small interfering RNAs (siRNAs) to gene silence the key intrinsic inhibitory NK cell molecules, SHP‐1, Cbl‐b, and c‐Cbl. The nanoparticles (NPs) target NK cells in vivo, silence inhibitory checkpoint signaling molecules, and unleash NK cell activity to eliminate tumors. Thus, the novel NP‐based system developed here may serve as a powerful tool for future NK cell‐based therapeutic approaches.
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- 2022
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26. Modulation of the intracellular inhibitory checkpoint SHP-1 enhances the antitumor activity of engineered NK cells
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Ben-Shmuel, Aviad, Biber, Guy, Sabag, Batel, and Barda-Saad, Mira
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- 2021
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27. Targeting the actin nucleation promoting factor WASp provides a therapeutic approach for hematopoietic malignancies
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Biber, Guy, Ben-Shmuel, Aviad, Noy, Elad, Joseph, Noah, Puthenveetil, Abhishek, Reiss, Neria, Levy, Omer, Lazar, Itay, Feiglin, Ariel, Ofran, Yanay, Kedmi, Meirav, Avigdor, Abraham, Fried, Sophia, and Barda-Saad, Mira
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- 2021
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28. A Serological Snapshot of COVID-19 Initial Stages in Israel by a 6-Plex Antigen Array
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Morly Fisher, Haim Levy, Ella Fatelevich, Yafa Afrimov, Amir Ben-Shmuel, Ronit Rosenfeld, Tal Noy-Porat, Itai Glinert, Assa Sittner, Asaf Biber, Ana Belkin, Elad Bar-David, Reut Puni, Itzchak Levy, Ohad Mazor, Shay Weiss, and Adva Mechaly
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SARS-CoV-2 ,spike ,nucleocapsid ,COVID-19 ,Israel ,serology ,Microbiology ,QR1-502 - Abstract
ABSTRACT The first case of SARS-CoV-2 was discovered in Israel in late February 2020. Three major outbreaks followed, resulting in over 800,000 cases and over 6,000 deaths by April 2021. Our aim was characterization of a serological snapshot of Israeli patients and healthy adults in the early months of the COVID-19 pandemic. Sera from 55 symptomatic COVID-19 patients and 146 healthy subjects (early-pandemic, reverse transcription-quantitative PCR [qRT-PCR]-negative), collected in Israel between March and April 2020, were screened for SARS-CoV-2-specific IgG, IgM, and IgA antibodies, using a 6-plex antigen microarray presenting the whole inactivated virus and five viral antigens: a stabilized version of the spike ectodomain (S2P), spike subunit 1 (S1), receptor-binding-domain (RBD), N-terminal-domain (NTD), and nucleocapsid (NC). COVID-19 patients, 4 to 40 days post symptom onset, presented specific IgG to all of the viral antigens (6/6) in 54 of the 55 samples (98% sensitivity). Specific IgM and IgA antibodies for all six antigens were detected in only 10% (5/55) and 4% (2/55) of the patients, respectively, suggesting that specific IgG is a superior serological marker for COVID-19. None of the qRT-PCR-negative sera reacted with all six viral antigens (100% specificity), and 48% (70/146) were negative throughout the panel. Our findings confirm a low seroprevalence of anti-SARS-CoV-2 antibodies in the Israeli adult population prior to the COVID-19 outbreak. We further suggest that the presence of low-level cross-reacting antibodies in naive individuals calls for a combined, multiantigen analysis for accurate discrimination between naive and exposed individuals. IMPORTANCE A 6-plex protein array presenting the whole inactivated virus and five nucleocapsid and spike-derived SARS-CoV-2 antigens was used to generate a serological snapshot of SARS-CoV-2 seroprevalence and seroconversion in Israel in the early months of the pandemic. Our findings confirm a very low seroprevalence of anti-SARS-CoV-2 antibodies in the Israeli adult population. We further propose that the presence of low-level nonspecific antibodies in naive individuals calls for a combined, multiantigen analysis for accurate discrimination between naive and exposed individuals enabling accurate determination of seroconversion. The developed assay is currently applied to evaluate immune responses to the Israeli vaccine during human phase I/II trials.
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- 2021
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29. Author Correction: LAMP-Seq enables sensitive, multiplexed COVID-19 diagnostics using molecular barcoding
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Ludwig, Kerstin U., Schmithausen, Ricarda M., Li, David, Jacobs, Max L., Hollstein, Ronja, Blumenstock, Katja, Liebing, Jana, Słabicki, Mikołaj, Ben-Shmuel, Amir, Israeli, Ofir, Weiss, Shay, Ebert, Thomas S., Paran, Nir, Rüdiger, Wibke, Wilbring, Gero, Feldman, David, Lippke, Bärbel, Ishorst, Nina, Hochfeld, Lara M., Beins, Eva C., Kaltheuner, Ines H., Schmitz, Maximilian, Wöhler, Aliona, Döhla, Manuel, Sib, Esther, Jentzsch, Marius, Moench, Eva-Maria C., Borrajo, Jacob D., Strecker, Jonathan, Reinhardt, Julia, Cleary, Brian, Geyer, Matthias, Hölzel, Michael, Macrae, Rhiannon, Nöthen, Markus M., Hoffmann, Per, Exner, Martin, Regev, Aviv, Zhang, Feng, and Schmid-Burgk, Jonathan L.
- Published
- 2022
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30. Actin Retrograde Flow Regulated by the Wiskott–Aldrich Syndrome Protein Drives the Natural Killer Cell Response
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Batel Sabag, Moria Levy, Jessica Kivelevitz, Nataly Dashevsky, Aviad Ben-Shmuel, Abhishek Puthenveetil, Fatima Awwad, and Mira Barda-Saad
- Subjects
ARF ,natural killer cells ,SHP-1 ,myosin IIA ,WASp ,mechanotransduction ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Understanding the crosstalk between natural killer (NK) cells and the tumor microenvironment (TME) has enhanced the potential of exploiting the interplay between activation and inhibition of NK cells for immunotherapy. This interaction is crucial for understanding how tumor cells escape NK cell immune surveillance. NK cell dysfunction is regulated by two molecular mechanisms, downregulated activating receptor ligand expression on the tumor cells, and upregulated inhibitory signals delivered to NK cells. Recent studies demonstrated the role of mechanotransduction in modulating NK cell responses in the TME. The immunological synapse represents a functional interface between the NK cell and its target, regulated by Actin Retrograde Flow (ARF), which drives the adhesion molecules and receptors toward the central zone of the immunological synapse (IS). Here, we further characterize the role of ARF in controlling the immune response of NK cells, using CRISPR/cas9-mediated Wiskott–Aldrich Syndrome protein (WASp) gene silencing of NK cells. We demonstrate that WASp regulates ARF velocity, affecting the conformation and function of the key NK inhibitory regulator, SH2-domain containing protein tyrosine phosphatase-1 (SHP-1), and consequently, the NK cell response. Our results demonstrate the potential of modulating the biophysical and intracellular regulation of NK activation as a promising approach for improving immunotherapy.
- Published
- 2022
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31. Mice with induced pulmonary morbidities display severe lung inflammation and mortality following exposure to SARS-CoV-2
- Author
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Reut Falach, Liat Bar-On, Shlomi Lazar, Tamar Kadar, Ohad Mazor, Moshe Aftalion, David Gur, Yentl Evgy, Ohad Shifman, Tamar Aminov, Ofir Israeli, Inbar Cohen-Gihon, Galia Zaide, Hila Gutman, Yaron Vagima, Efi Makdasi, Dana Stein, Ronit Rosenfeld, Ron Alcalay, Eran Zahavy, Haim Levy, Itai Glinert, Amir Ben-Shmuel, Tomer Israely, Sharon Melamed, Boaz Politi, Hagit Achdout, Shmuel Yitzhaki, Chanoch Kronman, and Tamar Sabo
- Subjects
COVID-19 ,Medicine - Abstract
Mice are normally unaffected by SARS coronavirus 2 (SARS-CoV-2) infection since the virus does not bind effectively to the murine version of the angiotensin-converting enzyme 2 (ACE2) receptor molecule. Here, we report that induced mild pulmonary morbidities rendered SARS-CoV-2–refractive CD-1 mice susceptible to this virus. Specifically, SARS-CoV-2 infection after application of low doses of the acute lung injury stimulants bleomycin or ricin caused severe disease in CD-1 mice, manifested by sustained body weight loss and mortality rates greater than 50%. Further studies revealed markedly higher levels of viral RNA in the lungs, heart, and serum of low-dose ricin–pretreated mice compared with non-pretreated mice. Furthermore, lung extracts prepared 2–3 days after viral infection contained subgenomic mRNA and virus particles capable of replication only when derived from the pretreated mice. The deleterious effects of SARS-CoV-2 infection were effectively alleviated by passive transfer of polyclonal or monoclonal antibodies generated against the SARS-CoV-2 receptor binding domain (RBD). Thus, viral cell entry in the sensitized mice seems to depend on viral RBD binding, albeit by a mechanism other than the canonical ACE2-mediated uptake route. This unique mode of viral entry, observed over a mildly injured tissue background, may contribute to the exacerbation of coronavirus disease 2019 (COVID-19) pathologies in patients with preexisting morbidities.
- Published
- 2021
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32. NLRP3 inflammasome in fibroblasts links tissue damage with inflammation in breast cancer progression and metastasis
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Nour Ershaid, Yoray Sharon, Hila Doron, Yael Raz, Ophir Shani, Noam Cohen, Lea Monteran, Leonor Leider-Trejo, Amir Ben-Shmuel, Muhammad Yassin, Motti Gerlic, Adit Ben-Baruch, Metsada Pasmanik-Chor, Roni Apte, and Neta Erez
- Subjects
Science - Abstract
Cancer associated fibroblasts (CAFs) are known to promote pro-tumorigenic inflammation. Here, the authors show that CAFs sense tissue damage and activate NLRP3 inflammasome and pro-inflammatory IL-1β secretion, and CAF-derived inflammasome signalling promotes breast tumour growth and metastasis.
- Published
- 2019
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33. The Role of the Cytoskeleton in Regulating the Natural Killer Cell Immune Response in Health and Disease: From Signaling Dynamics to Function
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Aviad Ben-Shmuel, Batel Sabag, Guy Biber, and Mira Barda-Saad
- Subjects
natural killer cells ,actin ,signaling ,cytoskeleton ,immune response ,Biology (General) ,QH301-705.5 - Abstract
Natural killer (NK) cells are innate lymphoid cells, which play key roles in elimination of virally infected and malignant cells. The balance between activating and inhibitory signals derived from NK surface receptors govern the NK cell immune response. The cytoskeleton facilitates most NK cell effector functions, such as motility, infiltration, conjugation with target cells, immunological synapse assembly, and cytotoxicity. Though many studies have characterized signaling pathways that promote actin reorganization in immune cells, it is not completely clear how particular cytoskeletal architectures at the immunological synapse promote effector functions, and how cytoskeletal dynamics impact downstream signaling pathways and activation. Moreover, pioneering studies employing advanced imaging techniques have only begun to uncover the architectural complexity dictating the NK cell activation threshold; it is becoming clear that a distinct organization of the cytoskeleton and signaling receptors at the NK immunological synapse plays a decisive role in activation and tolerance. Here, we review the roles of the actin cytoskeleton in NK cells. We focus on how actin dynamics impact cytolytic granule secretion, NK cell motility, and NK cell infiltration through tissues into inflammatory sites. We will also describe the additional cytoskeletal components, non-muscle Myosin II and microtubules that play pivotal roles in NK cell activity. Furthermore, special emphasis will be placed on the role of the cytoskeleton in assembly of immunological synapses, and how mutations or downregulation of cytoskeletal accessory proteins impact NK cell function in health and disease.
- Published
- 2021
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34. A single dose of recombinant VSV-∆G-spike vaccine provides protection against SARS-CoV-2 challenge
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Yahalom-Ronen, Yfat, Tamir, Hadas, Melamed, Sharon, Politi, Boaz, Shifman, Ohad, Achdout, Hagit, Vitner, Einat B., Israeli, Ofir, Milrot, Elad, Stein, Dana, Cohen-Gihon, Inbar, Lazar, Shlomi, Gutman, Hila, Glinert, Itai, Cherry, Lilach, Vagima, Yaron, Lazar, Shirley, Weiss, Shay, Ben-Shmuel, Amir, Avraham, Roy, Puni, Reut, Lupu, Edith, Bar-David, Elad, Sittner, Assa, Erez, Noam, Zichel, Ran, Mamroud, Emanuelle, Mazor, Ohad, Levy, Haim, Laskar, Orly, Yitzhaki, Shmuel, Shapira, Shmuel C., Zvi, Anat, Beth-Din, Adi, Paran, Nir, and Israely, Tomer
- Published
- 2020
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35. Unleashing Natural Killer Cells in the Tumor Microenvironment–The Next Generation of Immunotherapy?
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Aviad Ben-Shmuel, Guy Biber, and Mira Barda-Saad
- Subjects
natural killer cells ,inhibitory checkpoints ,immunotherapy ,tumor microenvironment ,tumor ligands ,Immunologic diseases. Allergy ,RC581-607 - Abstract
The emergence of immunotherapy for cancer treatment bears considerable clinical promise. Nevertheless, many patients remain unresponsive, acquire resistance, or suffer dose-limiting toxicities. Immune-editing of tumors assists their escape from the immune system, and the tumor microenvironment (TME) induces immune suppression through multiple mechanisms. Immunotherapy aims to bolster the activity of immune cells against cancer by targeting these suppressive immunomodulatory processes. Natural Killer (NK) cells are a heterogeneous subset of immune cells, which express a diverse array of activating and inhibitory germline-encoded receptors, and are thus capable of directly targeting and killing cancer cells without the need for MHC specificity. Furthermore, they play a critical role in triggering the adaptive immune response. Enhancing the function of NK cells in the context of cancer is therefore a promising avenue for immunotherapy. Different NK-based therapies have been evaluated in clinical trials, and some have demonstrated clinical benefits, especially in the context of hematological malignancies. Solid tumors remain much more difficult to treat, and the time point and means of intervention of current NK-based treatments still require optimization to achieve long term effects. Here, we review recently described mechanisms of cancer evasion from NK cell immune surveillance, and the therapeutic approaches that aim to potentiate NK function. Specific focus is placed on the use of specialized monoclonal antibodies against moieties on the cancer cell, or on both the tumor and the NK cell. In addition, we highlight newly identified mechanisms that inhibit NK cell activity in the TME, and describe how biochemical modifications of the TME can synergize with current treatments and increase susceptibility to NK cell activity.
- Published
- 2020
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36. Using old antibiotics to treat ancient bacterium-β-lactams for Bacillus anthracis meningitis.
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Assa Sittner, Amir Ben-Shmuel, Itai Glinert, Elad Bar-David, Josef Schlomovitz, David Kobiler, Shay Weiss, and Haim Levy
- Subjects
Medicine ,Science - Abstract
As Bacillus anthracis spores pose a proven bio-terror risk, the treatment focus has shifted from exposed populations to anthrax patients and the need for effective antibiotic treatment protocols increases. The CDC recommends carbapenems and Linezolid (oxazolidinone), for the treatment of anthrax, particularly for the late, meningeal stages of the disease. Previously we demonstrated that treatment with Meropenem or Linezolid, either as a single treatment or in combination with Ciprofloxacin, fails to protect rabbits from anthrax-meningitis. In addition, we showed that the failure of Meropenem was due to slow BBB penetration rather than low antibacterial activity. Herein, we tested the effect of increasing the dose of the antibiotic on treatment efficacy. We found that for full protection (88% cure rate) the dose should be increased four-fold from 40 mg/kg to 150 mg/kg. In addition, B. anthracis is a genetically stable bacterium and naturally occurring multidrug resistant B. anthracis strains have not been reported. In this manuscript, we report the efficacy of classical β-lactams as a single treatment or in combination with β-lactamase inhibitors in treating anthrax meningitis. We demonstrate that Ampicillin based treatment of anthrax meningitis is largely efficient (66%). The high efficacy (88-100%) of Augmentin (Amoxicillin and Clavulonic acid) and Unasyn (Ampicillin and Sulbactam) makes them a favorable choice due to reports of β-lactam resistant B. anthracis strains. Tazocin (Piperacillin and Tazobactam) proved inefficient compared to the highly efficient Augmentin and Unasyn.
- Published
- 2020
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37. Preliminary nonclinical safety and immunogenicity of an rVSV-ΔG-SARS-CoV-2-S vaccine in mice, hamsters, rabbits and pigs
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Noa Madar-Balakirski, Amir Rosner, Sharon Melamed, Boaz Politi, Michal Steiner, Hadas Tamir, Yfat Yahalom-Ronen, Elad Bar-David, Amir Ben-Shmuel, Assa Sittner, Itai Glinert, Shay Weiss, Erez Bar-Haim, Hila Cohen, Uri Elia, Hagit Achdout, Noam Erez, Shahar Rotem, Shlomi Lazar, Abraham Nyska, Shmuel Yitzhaki, Adi Beth-Din, Haim Levy, Nir Paran, Tomer Israely, and Hadar Marcus
- Subjects
Vaccines, Synthetic ,COVID-19 Vaccines ,Membrane Glycoproteins ,Mesocricetus ,Swine ,Health, Toxicology and Mutagenesis ,Vaccination ,COVID-19 ,General Medicine ,Toxicology ,Neutralizing antibodies ,Antibodies, Viral ,Antibodies, Neutralizing ,Mice, Inbred C57BL ,Nonclinical ,Mice ,Viral Envelope Proteins ,Immunotoxicology ,Cricetinae ,Animals ,Female ,Rabbits ,Safety ,Vaccine - Abstract
rVSV-ΔG-SARS-CoV-2-S is a clinical stage (Phase 2) replication competent recombinant vaccine against SARS-CoV-2. To evaluate the safety profile of the vaccine, a series of non-clinical safety, immunogenicity and efficacy studies were conducted in four animal species, using multiple doses (up to 108 Plaque Forming Units/animal) and dosing regimens. There were no treatment-related mortalities or any noticeable clinical signs in any of the studies. Compared to unvaccinated controls, hematology and biochemistry parameters were unremarkable and no adverse histopathological findings. There was no detectable viral shedding in urine, nor viral RNA detected in whole blood or serum samples seven days post vaccination. The rVSV-ΔG-SARS-CoV-2-S vaccination gave rise to neutralizing antibodies, cellular immune responses, and increased lymphocytic cellularity in the spleen germinal centers and regional lymph nodes. No evidence for neurovirulence was found in C57BL/6 immune competent mice or in highly sensitive type I interferon knock-out mice. Vaccine virus replication and distribution in K18-human Angiotensin-converting enzyme 2-transgenic mice showed a gradual clearance from the vaccination site with no vaccine virus recovered from the lungs. The nonclinical data suggest that the rVSV-ΔG-SARS-CoV-2-S vaccine is safe and immunogenic. These results supported the initiation of clinical trials, currently in Phase 2. Supplementary Information The online version contains supplementary material available at 10.1007/s00204-021-03214-w.
- Published
- 2022
38. Coupling immuno-magnetic capture with LC–MS/MS(MRM) as a sensitive, reliable, and specific assay for SARS-CoV-2 identification from clinical samples
- Author
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Ofir Schuster, Yafit Atiya-Nasagi, Osnat Rosen, Anat Zvi, Itai Glinert, Amir Ben Shmuel, Shay Weiss, Orly Laskar, and Liron Feldberg
- Subjects
Immunomagnetic capture ,LC–MS/MS(MRM) ,Signal to noise ratio ,Clinical samples ,SARS-CoV-2 ,Immunomagnetic Separation ,COVID-19 ,Antibodies, Viral ,Biochemistry ,Sensitivity and Specificity ,Analytical Chemistry ,COVID-19 Testing ,Tandem Mass Spectrometry ,Nasopharynx ,Humans ,Amino Acid Sequence ,Peptides ,Biomarkers ,Research Paper ,Chromatography, Liquid - Abstract
Graphical abstract Recently, numerous diagnostic approaches from different disciplines have been developed for SARS-CoV-2 diagnosis to monitor and control the COVID-19 pandemic. These include MS-based assays, which provide analytical information on viral proteins. However, their sensitivity is limited, estimated to be 5 × 104 PFU/ml in clinical samples. Here, we present a reliable, specific, and rapid method for the identification of SARS-CoV-2 from nasopharyngeal (NP) specimens, which combines virus capture followed by LC–MS/MS(MRM) analysis of unique peptide markers. The capture of SARS-CoV-2 from the challenging matrix, prior to its tryptic digestion, was accomplished by magnetic beads coated with polyclonal IgG-α-SARS-CoV-2 antibodies, enabling sample concentration while significantly reducing background noise interrupting with LC–MS analysis. A sensitive and specific LC–MS/MS(MRM) analysis method was developed for the identification of selected tryptic peptide markers. The combined assay, which resulted in S/N ratio enhancement, achieved an improved sensitivity of more than 10-fold compared with previously described MS methods. The assay was validated in 29 naive NP specimens, 19 samples were spiked with SARS-CoV-2 and 10 were used as negative controls. Finally, the assay was successfully applied to clinical NP samples (n = 26) pre-determined as either positive or negative by RT-qPCR. This work describes for the first time a combined approach for immuno-magnetic viral isolation coupled with MS analysis. This method is highly reliable, specific, and sensitive; thus, it may potentially serve as a complementary assay to RT-qPCR, the gold standard test. This methodology can be applied to other viruses as well. Supplementary Information The online version contains supplementary material available at 10.1007/s00216-021-03831-5.
- Published
- 2022
39. Modeling plasticity by non-continuous deformation
- Author
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Ben-Shmuel, Yaron and Altus, Eli
- Published
- 2016
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40. Commentary: Integrins Modulate T Cell Receptor Signaling by Constraining Actin Flow at the Immunological Synapse
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Aviad Ben-Shmuel, Noah Joseph, and Mira Barda-Saad
- Subjects
mechanotransduction ,cytoskeleton ,NK cells ,actin retrograde flow ,SHP-1 ,Immunologic diseases. Allergy ,RC581-607 - Published
- 2018
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41. In Vitro and In Vivo Therapeutic Potential of 6,6′-Dihydroxythiobinupharidine (DTBN) from Nuphar lutea on Cells and K18- hACE2 Mice Infected with SARS-CoV-2.
- Author
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Weiss, Shay, Waidha, Kamran, Rajendran, Saravanakumar, Benharroch, Daniel, Khalilia, Jannat, Levy, Haim, Bar-David, Elad, Golan-Goldhirsh, Avi, Gopas, Jacob, and Ben-Shmuel, Amir
- Subjects
COVID-19 ,SARS-CoV-2 ,DNA topoisomerase I ,SMALL molecules ,MEASLES virus ,DNA topoisomerase II ,BOVINE viral diarrhea - Abstract
We have previously published research on the anti-viral properties of an alkaloid mixture extracted from Nuphar lutea, the major components of the partially purified mixture found by NMR analysis. These are mostly dimeric sesquiterpene thioalkaloids called thiobinupharidines and thiobinuphlutidines against the negative strand RNA measles virus (MV). We have previously reported that this extract inhibits the MV as well as its ability to downregulate several MV proteins in persistently MV-infected cells, especially the P (phospho)-protein. Based on our observation that the Nuphar extract is effective in vitro against the MV, and the immediate need that the coronavirus disease 2019 (COVID-19) pandemic created, we tested here the ability of 6,6′-dihydroxythiobinupharidine DTBN, an active small molecule, isolated from the Nuphar lutea extract, on COVID-19. As shown here, DTBN effectively inhibits SARS-CoV-2 production in Vero E6 cells at non-cytotoxic concentrations. The short-term daily administration of DTBN to infected mice delayed the occurrence of severe clinical outcomes, lowered virus levels in the lungs and improved survival with minimal changes in lung histology. The viral load on lungs was significantly reduced in the treated mice. DTBN is a pleiotropic small molecule with multiple targets. Its anti-inflammatory properties affect a variety of pathogens including SARS-CoV-2 as shown here. Its activity appears to target both pathogen specific (as suggested by docking analysis) as well as cellular proteins, such as NF-κB, PKCs, cathepsins and topoisomerase 2, that we have previously identified in our work. Thus, this combined double action of virus inhibition and anti-inflammatory activity may enhance the overall effectivity of DTBN. The promising results from this proof-of-concept in vitro and in vivo preclinical study should encourage future studies to optimize the use of DTBN and/or its molecular derivatives against this and other related viruses. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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42. Activating Transcription Factor-5 Knockdown Reduces Aggressiveness of Mammary Tumor Cells and Attenuates Mammary Tumor Growth
- Author
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Sarit Ben-Shmuel, Rola Rashed, Ran Rostoker, Elina Isakov, Zila Shen-Orr, and Derek LeRoith
- Subjects
breast cancer ,activating transcription factor-5 ,CD24 ,autophagy ,insulin ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
Activating transcription factor-5 (ATF5) is an anti-apoptotic factor and has been implicated in enhancing the survival of cancer cells under stress and in regulating the autophagy process. Targeting ATF5 in anticancer therapy may be particularly attractive because of its differential role in cancer cells than in non-transformed cells, thus allowing specificity of the treatment. Using the delivery of short hairpin RNA vectors into the Mvt1 and Met1 cell lines, we tested the role of ATF5 in the development of mammary tumors in vivo and in regulating proliferation and migration of these cells in vitro. In this study, we demonstrate that knockdown of ATF5 (ATF5-KD) in both cell lines results in a decreased tumor volume and weight, as well as in a reduced proliferation rate and migratory potential of the cells. In addition, ATF5-KD led to an increased autophagy flux and a shift in the sub-populations comprising Mvt1 cells from the aggressive CD24-positive cells toward less aggressive CD24-negative cells. Taken together, these findings suggest that ATF5 plays an important role in enhancing mammary tumor cells overall aggressiveness and in promoting mammary tumor growth and emphasize the possible benefit of anti-ATF5 therapy in breast cancer patients, particularly, against tumors characterized with the positive expression of cell surface CD24.
- Published
- 2017
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43. Pathology of wild-type and toxin-independent Bacillus anthracis meningitis in rabbits.
- Author
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Assa Sittner, Elad Bar-David, Itai Glinert, Amir Ben-Shmuel, Shay Weiss, Josef Schlomovitz, David Kobiler, and Haim Levy
- Subjects
Medicine ,Science - Abstract
Hemorrhagic meningitis is considered a complication of anthrax and was reported in about 50% of deadly cases in humans and non-human primates (NHP). Recently we demonstrated in Guinea pigs and rabbits that 100% of the B. anthracis-infected animals presented histopathology of meningitis at the time of death, some without any sign of hemorrhage. A similar pathology was observed in animals that succumbed following infection with the toxin deficient mutant, thus indicating that anthrax meningitis is a toxin-independent phenomenon. In this manuscript we describe a histopathological study of the B. anthracis infection of the central nervous system (CNS). Though we could find sporadic growth of the bacteria around blood vessels in the cortex, we report that the main infiltration route is the choroid plexus. We found massive destruction of entire sections of the choroid plexus coupled with massive aggregation of bacilli in the ventricles, in close proximity to the parenchyma. The choroid plexus also contained significant amounts of intravascular bacterial aggregates, often enclosed in what appear to be fibrin-like clots. The high concentration of these aggregates in areas of significant tissue destruction combined with the fact that capsular B. anthracis bacteria have a low tendency to adhere to endothelial cells, might suggest that these clots are used as an adherence mechanism by the bacteria. The major histopathological finding is meningitis. We find massive bacterial growth in the meninges without evidence of encephalitis, even when the bacteria emerge from a parenchymal blood vessel. Erythrocytes were present within the meningeal space but no clear vasculitis could be detected. Histology of the brain stem indicates meningitis, edema and hemorrhages that might explain death from suffocation due to direct damage to the respiratory center. All of these processes are toxin-independent, since they were observed following infection with either the wild type strain or the toxin-deficient mutant. Herein, we propose that the first step of anthrax-meningitis is bacterial adhesion to the blood vessels by manipulating coagulation, mainly in the choroid plexus. The trapped bacteria then destroy sections of the choroid plexus, resulting in penetration into the CSF, leading to meningitis and hemorrhage. Death could be the result of increased intracranial pressure and/or damage to the brain stem.
- Published
- 2017
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44. Induction of the intestinal stem cell signature gene SMOC-2 is required for L1-mediated colon cancer progression
- Author
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Shvab, A, Haase, G, Ben-Shmuel, A, Gavert, N, Brabletz, T, Dedhar, S, and Ben-Ze'ev, A
- Published
- 2016
- Full Text
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45. Specific and Rapid SARS-CoV-2 Identification Based on LC-MS/MS Analysis
- Author
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Anat Zvi, Shmuel Yitzhaki, Liron Feldberg, Osnat Rosen, Ofir Schuster, Amir Ben-Shmuel, Ohad Shifman, Orly Laskar, and Hagit Achdout
- Subjects
chemistry.chemical_classification ,Chromatography ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,General Chemical Engineering ,In silico ,viruses ,Ms analysis ,Peptide ,Computational biology ,General Chemistry ,Gold standard (test) ,Biology ,Mass spectrometry ,Virus ,Article ,Matrix (chemical analysis) ,Chemistry ,Real-time polymerase chain reaction ,chemistry ,Lc ms ms ,Identification (biology) ,QD1-999 - Abstract
SARS-CoV-2, the etiologic agent of the COVID-19 pandemic, emerged as the cause of a global crisis. Rapid and reliable clinical diagnosis is essential for effectively controlling transmission. The gold standard assay for SARS-CoV-2 identification is the highly sensitive real-time quantitative polymerase chain reaction (RT-qPCR); however, this assay depends on specialized reagents and may suffer from false results. Thus, additional assays based on different approaches could be beneficial. Here, we present a novel method for SARS-CoV-2 identification based on mass spectrometry. The approach we implemented combines a multistep procedure for the rational down-selection of a set of reliable markers out of all optional in silico derived tryptic peptides in viral proteins, followed by monitoring of peptides derived from tryptic digests of purified proteins, cell-cultured SARS-CoV-2, and nasopharyngeal (NP) swab matrix spiked with the virus. The marker selection was based on specificity to SARS-CoV-2 and on analytical parameters including sensitivity, linearity, and reproducibility. The final assay is based on six unique and specific peptide markers for SARS-CoV-2 identification. The simple and rapid (2.5 h) protocol we developed consists of virus heat inactivation and denaturation, tryptic digestion, and identification of the selected markers by liquid chromatography coupled to high-resolution mass spectrometry (LC-MS/MS). The developed assay enabled the identification of 104 PFU/mL SARS-CoV-2 spiked into buffer. Finally, the assay was successfully applied to 16 clinical samples diagnosed by RT-qPCR, achieving 94% concordance with the current gold standard assay. To conclude, the novel MS-based assay described here is specific, rapid, simple, and is believed to provide a complementary assay to the RT-qPCR method.
- Published
- 2021
46. Infection with a Nonencapsulated Bacillus anthracis Strain in Rabbits—The Role of Bacterial Adhesion and the Potential for a Safe Live Attenuated Vaccine
- Author
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Itai Glinert, Shay Weiss, Assa Sittner, Elad Bar-David, Amir Ben-Shmuel, Josef Schlomovitz, David Kobiler, and Haim Levy
- Subjects
Bacillus anthacis ,vaccine strain ,BslA ,cell adherence ,encephalitis ,CNS infection ,Medicine - Abstract
Nonencapsulated (∆pXO2) Bacillus anthracis strains are commonly used as vaccines and for anthrax research, mainly in the mouse model. Previously, we demonstrated that the infection of rabbits, intranasally or subcutaneously, with the spores of a fully virulent strain results in the systemic dissemination of the bacteria, meningitis, and death, whereas ∆pXO2 strains are fully attenuated in this animal model. We used the intravenous inoculation of rabbits to study the pathogenicity of the ∆pXO2 strain infection. Bacteremia, brain bacterial burden, and pathology were used as criteria to compare the Vollum∆pXO2 disease to the wild type Vollum infection. To test the role of adhesion in the virulence of Vollum∆pXO2, we deleted the major adhesion protein BslA and tested the virulence and immunogenicity of this mutant. We found that 50% of the rabbits succumb to Vollum∆pXO2 strain following i.v. infection, a death that was accompanied with significant neurological symptoms. Pathology revealed severe brain infection coupled with an atypical massive bacterial growth into the parenchyma. Contrary to the Vollum strain, deletion of the bslA gene fully attenuated the ∆pXO2 strain. Though the Vollum∆pXO2 cannot serve as a model for B. anthracis pathogenicity in rabbits, deletion of the bslA gene prevents central nervous system (CNS) infections, possibly leading to the generation of a safer vaccine.
- Published
- 2018
- Full Text
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47. Revisiting SARS-CoV-2 environmental contamination by patients with COVID-19: The Omicron variant does not differ from previous strains
- Author
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Glinert, Itai, Ben-Shmuel, Amir, Szwartcwort-Cohen, Moran, Beth-din, Adi, Laskar, Orly, Barlev-Gross, Moria, Melamed, Sharon, Arbell, Noga, Levy, Haim, Horowitz, Netanel A, and Weiss, Shay
- Published
- 2022
- Full Text
- View/download PDF
48. A single dose of recombinant VSV-∆G-spike vaccine provides protection against SARS-CoV-2 challenge
- Author
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Hila Gutman, Shirley Lazar, Itai Glinert, Anat Zvi, Shmuel Yitzhaki, Tomer Israely, Noam Erez, Reut Puni, Shmuel C. Shapira, Einat B. Vitner, Shay Weiss, Dana Stein, Sharon Melamed, Inbar Cohen-Gihon, Haim Levy, Assa Sittner, Adi Beth-Din, Shlomi Lazar, Ohad Mazor, Yaron Vagima, Roy Avraham, Hagit Achdout, Boaz Politi, Ofir Israeli, Yfat Yahalom-Ronen, Nir Paran, Ran Zichel, Hadas Tamir, Edith Lupu, Lilach Cherry, Elad Milrot, Emanuelle Mamroud, Ohad Shifman, Elad Bar-David, Orly Laskar, and Amir Ben-Shmuel
- Subjects
0301 basic medicine ,viruses ,General Physics and Astronomy ,Antibodies, Viral ,law.invention ,0302 clinical medicine ,law ,Cricetinae ,skin and connective tissue diseases ,Antigens, Viral ,Lung ,Vaccines, Synthetic ,Vaccines ,Multidisciplinary ,biology ,Vaccination ,Viral Load ,030220 oncology & carcinogenesis ,Spike Glycoprotein, Coronavirus ,Recombinant DNA ,Antibody ,Viral load ,COVID-19 Vaccines ,Science ,Dose-Response Relationship, Immunologic ,Hamster ,Genome, Viral ,Vesicular stomatitis Indiana virus ,Article ,General Biochemistry, Genetics and Molecular Biology ,Cell Line ,03 medical and health sciences ,Antigen ,Animals ,SARS-CoV-2 ,fungi ,Body Weight ,COVID-19 ,General Chemistry ,Viral membrane ,Virology ,respiratory tract diseases ,body regions ,Mice, Inbred C57BL ,Disease Models, Animal ,030104 developmental biology ,Cell culture ,Mutation ,biology.protein - Abstract
The COVID-19 pandemic caused by SARS-CoV-2 imposes an urgent need for rapid development of an efficient and cost-effective vaccine, suitable for mass immunization. Here, we show the development of a replication competent recombinant VSV-∆G-spike vaccine, in which the glycoprotein of VSV is replaced by the spike protein of SARS-CoV-2. In-vitro characterization of this vaccine indicates the expression and presentation of the spike protein on the viral membrane with antigenic similarity to SARS-CoV-2. A golden Syrian hamster in-vivo model for COVID-19 is implemented. We show that a single-dose vaccination results in a rapid and potent induction of SARS-CoV-2 neutralizing antibodies. Importantly, vaccination protects hamsters against SARS-CoV-2 challenge, as demonstrated by the abrogation of body weight loss, and alleviation of the extensive tissue damage and viral loads in lungs and nasal turbinates. Taken together, we suggest the recombinant VSV-∆G-spike as a safe, efficacious and protective vaccine against SARS-CoV-2., Here, the authors generate a replication-competent VSV based vaccine expressing SARS-CoV-2 spike protein and show protection in the hamster model with one dose. Analysis of the antibody response in mice shows induction of neutralizing antibodies and suggests a desirable Th1-biased response to the vaccine.
- Published
- 2020
49. Turning high-throughput structural biology into predictive inhibitor design.
- Author
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Saar, Kadi L., McCorkindale, William, Fearon, Daren, Boby, Melissa, Barr, Haim, Ben-Shmuel, Amir, London, Nir, von Delft, Frank, Chodera, John D., and Lee, Alpha A.
- Subjects
COSMOCHEMISTRY ,DRUG design ,BIOLOGY ,SIMPLE machines ,MACHINE learning ,EXCHANGE - Abstract
A common challenge in drug design pertains to finding chemical modifications to a ligand that increases its affinity to the target protein. An underutilized advance is the increase in structural biology throughput, which has progressed from an artisanal endeavor to a monthly throughput of hundreds of different ligands against a protein in modern synchrotrons. However, the missing piece is a framework that turns high-throughput crystallography data into predictive models for ligand design. Here, we designed a simple machine learning approach that predicts protein-ligand affinity from experimental structures of diverse ligands against a single protein paired with biochemical measurements. Our key insight is using physics-based energy descriptors to represent protein-ligand complexes and a learning-to-rank approach that infers the relevant differences between binding modes. We ran a high-throughput crystallography campaign against the SARS-CoV-2 main protease (M
Pro ), obtaining parallel measurements of over 200 protein-ligand complexes and their binding activities. This allows us to design one-step library syntheses which improved the potency of two distinct micromolar hits by over 10-fold, arriving at a noncovalent and nonpeptidomimetic inhibitor with 120 nM antiviral efficacy. Crucially, our approach successfully extends ligands to unexplored regions of the binding pocket, executing large and fruitful moves in chemical space with simple chemistry. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
50. Alternate atxA and acpA dependent response of Bacillus anthracis to serum, HCO3- and CO2.
- Author
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Glinert, Itai, Bar-David, Elad, Ben-Shmuel, Amir, Sittner, Assa, Puni, Reut, Laredo, Shira, Kobiler, David, Weiss, Shay, and Levy, Haim
- Subjects
BACILLUS anthracis ,DENDRITIC cells ,FACTORS of production ,CELL migration ,QUORUM sensing ,TOXINS - Abstract
Bacillus anthracis overcomes host immune responses by producing capsule and secreting toxins. Production of these virulence factors in response to entering the host environment was shown to be regulated by atxA, the major virulence regulator, known to be activated by HCO
3 - and CO2 . While toxin production is regulated directly by atxA, capsule production is independently mediated by two regulators; acpA and acpB. In addition, it was demonstrated that acpA has at least two promotors, one of them shared with atxA. We used a genetic approach to study capsule and toxin production under different conditions. Unlike previous works utilizing NBY, CA or R-HCO3 - medium under CO2 enriched conditions, we used a sDMEM-based medium. Thus, toxin and capsule production can be induced in ambient or CO2 enriched atmosphere. Using this system, we could differentiate between induction by 10% NRS, 10% CO2 or 0.75% HCO3 - . In response to high CO2 , capsule production is induced by acpA based response in an atxA-independent manner, with little to no toxin (protective antigen PA) production. atxA based response is activated in response to serum independently of CO2 , inducing toxin and capsule production in an acpA or acpB dependent manner. HCO3 - was also found to activate atxA based response, but in non-physiological concentrations. Our findings may help explain the first stages of inhalational infection, in which spores germinating in dendritic cells require protection (by encapsulation) without affecting cell migration to the draining lymph-node by toxin secretion. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
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