196 research outputs found

    Internal lipid synthesis and vesicle growth as a step toward self-reproduction of the minimal cell

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    One of the major properties of the semi-synthetic minimal cell, as a model for early living cells, is the ability to self-reproduce itself, and the reproduction of the boundary layer or vesicle compartment is part of this process. A minimal bio-molecular mechanism based on the activity of one single enzyme, the FAS-B (Fatty Acid Synthase) Type I enzyme from Brevibacterium ammoniagenes, is encapsulated in 1-palmitoyl-2oleoyl-sn-glycero-3-phosphatidylcholine (POPC) liposomes to control lipid synthesis. Consequently molecules of palmitic acid released from the FAS catalysis, within the internal lumen, move toward the membrane compartment and become incorporated into the phospholipid bilayer. As a result the vesicle membranes change in lipid composition and liposome growth can be monitored. Here we report the first experiments showing vesicles growth by catalysis of one enzyme only that produces cell boundary from within. This is the prototype of the simplest autopoietic minimal cell

    Immunological study of COVID-19 vaccine candidate based on recombinant spike trimer protein from different SARS-CoV-2 variants of concern

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    The emergency of new SARS-CoV-2 variants that feature increased immune escape marks an urgent demand for better vaccines that will provide broader immunogenicity. Here, we evaluated the immunogenic capacity of vaccine candidates based on the recombinant trimeric spike protein (S) of different SARS-CoV-2 variants of concern (VOC), including the ancestral Wuhan, Beta and Delta viruses. In particular, we assessed formulations containing either single or combined S protein variants. Our study shows that the formulation containing the single S protein from the ancestral Wuhan virus at a concentration of 2µg (SW2-Vac 2µg) displayed in the mouse model the highest IgG antibody levels against all the three (Wuhan, Beta, and Delta) SARS-CoV-2 S protein variants tested. In addition, this formulation induced significantly higher neutralizing antibody titers against the three viral variants when compared with authorized Gam-COVID-Vac-rAd26/rAd5 (Sputnik V) or ChAdOx1 (AstraZeneca) vaccines. SW2-Vac 2µg was also able to induce IFN-gamma and IL-17, memory CD4 populations and follicular T cells. Used as a booster dose for schedules performed with different authorized vaccines, SW2-Vac 2µg vaccine candidate also induced higher levels of total IgG and IgG isotypes against S protein from different SARS-CoV-2 variants in comparison with those observed with homologous 3-dose schedule of Sputnik V or AstraZeneca. Moreover, SW2-Vac 2µg booster induced broadly strong neutralizing antibody levels against the three tested SARS-CoV-2 variants. SW2-Vac 2µg booster also induced CD4+ central memory, CD4+ effector and CD8+ populations. Overall, the results demonstrate that SW2-Vac 2 µg is a promising formulation for the development of a next generation COVID-19 vaccine.Fil: Rudi, Erika. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Biotecnología y Biología Molecular. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Biotecnología y Biología Molecular; ArgentinaFil: Martin Aispuro, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Biotecnología y Biología Molecular. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Biotecnología y Biología Molecular; ArgentinaFil: Zurita, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Biotecnología y Biología Molecular. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Biotecnología y Biología Molecular; ArgentinaFil: González López Ledesma, María Mora. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Bottero, Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Biotecnología y Biología Molecular. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Biotecnología y Biología Molecular; ArgentinaFil: Malito, Juan Pablo Alfonso. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología e Innovaciones Tecnológicas. Grupo Vinculado Incuinta al IVIT | Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Virología e Innovaciones Tecnológicas. Grupo Vinculado Incuinta al IVIT; ArgentinaFil: Gabrielli, Magali. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Biotecnología y Biología Molecular. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Biotecnología y Biología Molecular; ArgentinaFil: Gaillard, María Emilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Biotecnología y Biología Molecular. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Biotecnología y Biología Molecular; ArgentinaFil: Stuible, Matthew. National Research Council Canada, Montreal; CanadáFil: Durocher, Yves. National Research Council Canada, Montreal; CanadáFil: Gamarnik, Andrea Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Wigdorovitz, Andrés. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion En Ciencias Veterinarias y Agronomicas. Instituto de Virologia E Innovaciones Tecnologicas. Grupo Vinculado Incuinta Al Ivit | Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Virologia E Innovaciones Tecnologicas. Grupo Vinculado Incuinta Al Ivit.; ArgentinaFil: Hozbor, Daniela Flavia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Biotecnología y Biología Molecular. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Biotecnología y Biología Molecular; Argentin

    Einbindung des ECOLOG-Modells "E3Net" und Integration neuer methodischer Ansätze in das IKARUS-Instrumentarium (ECOLOG II)

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    Ziel des Forschungsvorhabens „Einbindung des ECOLOG-Modells ‘E³Net’ und Integration neuer methodischer Ansätze in das IKARUS-Instrumentarium (ECOLOG II)' war es, veschiedene Modellbildungsansätze und Werkzeuge für die energiewirtschaftliche Analyse zu einem Instrumentarium zusammenzufügen. Dazu wurde auf die Projekte IKARUS „Instrumente für Klimagasreduktionsstrategien' und ECOLOG „Entwicklung eines Computermodells mit linearer Optimierung zur Abbildung eines regionalisierten Energiesystems am Beispiel Gesamtdeutschlands' aufgebaut. Das Projekt ECOLOG II umfaßt Weiterentwicklungen in den folgenden sechs Aufgabenbereichen: (1) Integration von E³Net in das IKARUS-Instrumentarium; (2) Nichtlineare Modellansätze für E³Net; (3) Makroökonomische Erweiterung von E³Net; (4) Entwicklung und Anwendung eines multisektoralen Energiewirtschaftsmodells NEWAGE; (5) Entwicklung eines Simulationsansatzes für Energiesystemmodelle PlaNet; (6) Erweiterung der Analysemöglichkeiten von NetWork. Im Rahmen des Forschungsvorhabens wurden eine Kopplung der FIZ-Technik-Datenbank an die Datenbank NetWork, eine Verbindung der FIZ-LP-Datenbank mit NetWork, eine Überführung des IKARUS-LP-Datensatzes in eine Fallstudie für das optimierende Energiesystemmodell E³Net, ein optimierendes Energiesystemmodell mit preiselastischer Nachfrage E³Micro, ein Gleichgewichtsmodell NEWAGE, das prototypisch ein prozeßtechnisches Energieversorgungsmodell in ein übergeordnetes gesamtwirtschaftliches Modell integriert, ein Simulationsmodell PlaNet sowie ein Netzwerkdesigner und -analyst (NDA) realisiert und durch exemplarische Fallstudien, die im Kontext des IKARUS-Instrumentariums stehen, getestet

    Einbindung des ECOLOG-Modells "E3Net" und Integration neuer methodischer Ansätze in das IKARUS-Instrumentarium (ECOLOG II)

    Get PDF
    Ziel des Forschungsvorhabens „Einbindung des ECOLOG-Modells ‘E³Net’ und Integration neuer methodischer Ansätze in das IKARUS-Instrumentarium (ECOLOG II)' war es, veschiedene Modellbildungsansätze und Werkzeuge für die energiewirtschaftliche Analyse zu einem Instrumentarium zusammenzufügen. Dazu wurde auf die Projekte IKARUS „Instrumente für Klimagasreduktionsstrategien' und ECOLOG „Entwicklung eines Computermodells mit linearer Optimierung zur Abbildung eines regionalisierten Energiesystems am Beispiel Gesamtdeutschlands' aufgebaut. Das Projekt ECOLOG II umfaßt Weiterentwicklungen in den folgenden sechs Aufgabenbereichen: (1) Integration von E³Net in das IKARUS-Instrumentarium; (2) Nichtlineare Modellansätze für E³Net; (3) Makroökonomische Erweiterung von E³Net; (4) Entwicklung und Anwendung eines multisektoralen Energiewirtschaftsmodells NEWAGE; (5) Entwicklung eines Simulationsansatzes für Energiesystemmodelle PlaNet; (6) Erweiterung der Analysemöglichkeiten von NetWork. Im Rahmen des Forschungsvorhabens wurden eine Kopplung der FIZ-Technik-Datenbank an die Datenbank NetWork, eine Verbindung der FIZ-LP-Datenbank mit NetWork, eine Überführung des IKARUS-LP-Datensatzes in eine Fallstudie für das optimierende Energiesystemmodell E³Net, ein optimierendes Energiesystemmodell mit preiselastischer Nachfrage E³Micro, ein Gleichgewichtsmodell NEWAGE, das prototypisch ein prozeßtechnisches Energieversorgungsmodell in ein übergeordnetes gesamtwirtschaftliches Modell integriert, ein Simulationsmodell PlaNet sowie ein Netzwerkdesigner und -analyst (NDA) realisiert und durch exemplarische Fallstudien, die im Kontext des IKARUS-Instrumentariums stehen, getestet

    PTPN2, a Candidate Gene for Type 1 Diabetes, Modulates Interferon-γ–Induced Pancreatic β-Cell Apoptosis

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    OBJECTIVE: The pathogenesis of type 1 diabetes has a strong genetic component. Genome-wide association scans recently identified novel susceptibility genes including the phosphatases PTPN22 and PTPN2. We hypothesized that PTPN2 plays a direct role in beta-cell demise and assessed PTPN2 expression in human islets and rat primary and clonal beta-cells, besides evaluating its role in cytokine-induced signaling and beta-cell apoptosis. RESEARCH DESIGN AND METHODS: PTPN2 mRNA and protein expression was evaluated by real-time PCR and Western blot. Small interfering (si)RNAs were used to inhibit the expression of PTPN2 and downstream STAT1 in beta-cells, allowing the assessment of cell death after cytokine treatment. RESULTS: PTPN2 mRNA and protein are expressed in human islets and rat beta-cells and upregulated by cytokines. Transfection with PTPN2 siRNAs inhibited basal- and cytokine-induced PTPN2 expression in rat beta-cells and dispersed human islets cells. Decreased PTPN2 expression exacerbated interleukin (IL)-1beta + interferon (IFN)-gamma-induced beta-cell apoptosis and turned IFN-gamma alone into a proapoptotic signal. Inhibition of PTPN2 amplified IFN-gamma-induced STAT1 phosphorylation, whereas double knockdown of both PTPN2 and STAT1 protected beta-cells against cytokine-induced apoptosis, suggesting that STAT1 hyperactivation is responsible for the aggravation of cytokine-induced beta-cell death in PTPN2-deficient cells. CONCLUSIONS: We identified a functional role for the type 1 diabetes candidate gene PTPN2 in modulating IFN-gamma signal transduction at the beta-cell level. PTPN2 regulates cytokine-induced apoptosis and may thereby contribute to the pathogenesis of type 1 diabetes

    Cortactin regulates cofilin and N-WASp activities to control the stages of invadopodium assembly and maturation

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    Invadopodia are matrix-degrading membrane protrusions in invasive carcinoma cells. The mechanisms regulating invadopodium assembly and maturation are not understood. We have dissected the stages of invadopodium assembly and maturation and show that invadopodia use cortactin phosphorylation as a master switch during these processes. In particular, cortactin phosphorylation was found to regulate cofilin and Arp2/3 complex–dependent actin polymerization. Cortactin directly binds cofilin and inhibits its severing activity. Cortactin phosphorylation is required to release this inhibition so cofilin can sever actin filaments to create barbed ends at invadopodia to support Arp2/3-dependent actin polymerization. After barbed end formation, cortactin is dephosphorylated, which blocks cofilin severing activity thereby stabilizing invadopodia. These findings identify novel mechanisms for actin polymerization in the invadopodia of metastatic carcinoma cells and define four distinct stages of invadopodium assembly and maturation consisting of invadopodium precursor formation, actin polymerization, stabilization, and matrix degradation

    Heterologous booster with a novel formulation containing glycosylated trimeric S protein is effective against Omicron

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    In this study, we evaluated the efficacy of a heterologous three-dose vaccination schedule against the Omicron BA.1 SARS-CoV-2 variant infection using a mouse intranasal challenge model. The vaccination schedules tested in this study consisted of a primary series of 2 doses covered by two commercial vaccines: an mRNA-based vaccine (mRNA1273) or a non-replicative vector-based vaccine (AZD1222/ChAdOx1, hereafter referred to as AZD1222). These were followed by a heterologous booster dose using one of the two vaccine candidates previously designed by us: one containing the glycosylated and trimeric spike protein (S) from the ancestral virus (SW-Vac 2µg), and the other from the Delta variant of SARS-CoV-2 (SD-Vac 2µg), both formulated with Alhydrogel as an adjuvant. For comparison purposes, homologous three-dose schedules of the commercial vaccines were used. The mRNA-based vaccine, whether used in heterologous or homologous schedules, demonstrated the best performance, significantly increasing both humoral and cellular immune responses. In contrast, for the schedules that included the AZD1222 vaccine as the primary series, the heterologous schemes showed superior immunological outcomes compared to the homologous 3-dose AZD1222 regimen. For these schemes no differences were observed in the immune response obtained when SW-Vac 2µg or SD-Vac 2µg were used as a booster dose. Neutralizing antibody levels against Omicron BA.1 were low, especially for the schedules using AZD1222. However, a robust Th1 profile, known to be crucial for protection, was observed, particularly for the heterologous schemes that included AZD1222. All the tested schedules were capable of inducing populations of CD4 T effector, memory, and follicular helper T lymphocytes. It is important to highlight that all the evaluated schedules demonstrated a satisfactory safety profile and induced multiple immunological markers of protection. Although the levels of these markers were different among the tested schedules, they appear to complement each other in conferring protection against intranasal challenge with Omicron BA.1 in K18-hACE2 mice. In summary, the results highlight the potential of using the S protein (either ancestral Wuhan or Delta variant)-based vaccine formulation as heterologous boosters in the management of COVID-19, particularly for certain commercial vaccines currently in use
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