26 research outputs found
Therapeutic protein transduction of mammalian cells and mice by nucleic acid-free lentiviral nanoparticles
The straightforward production and dose-controlled administration of protein therapeutics remain major challenges for the biopharmaceutical manufacturing and gene therapy communities. Transgenes linked to HIV-1-derived vpr and pol-based protease cleavage (PC) sequences were co-produced as chimeric fusion proteins in a lentivirus production setting, encapsidated and processed to fusion peptide-free native protein in pseudotyped lentivirions for intracellular delivery and therapeutic action in target cells. Devoid of viral genome sequences, protein-transducing nanoparticles (PTNs) enabled transient and dose-dependent delivery of therapeutic proteins at functional quantities into a variety of mammalian cells in the absence of host chromosome modifications. PTNs delivering Manihot esculenta linamarase into rodent or human, tumor cell lines and spheroids mediated hydrolysis of the innocuous natural prodrug linamarin to cyanide and resulted in efficient cell killing. Following linamarin injection into nude mice, linamarase-transducing nanoparticles impacted solid tumor development through the bystander effect of cyanid
Therapeutic protein transduction of mammalian cells and mice by nucleic acid-free lentiviral nanoparticles
The straightforward production and dose-controlled administration of protein therapeutics remain major challenges for the biopharmaceutical manufacturing and gene therapy communities. Transgenes linked to HIV-1-derived vpr and pol-based protease cleavage (PC) sequences were co-produced as chimeric fusion proteins in a lentivirus production setting, encapsidated and processed to fusion peptide-free native protein in pseudotyped lentivirions for intracellular delivery and therapeutic action in target cells. Devoid of viral genome sequences, protein-transducing nanoparticles (PTNs) enabled transient and dose-dependent delivery of therapeutic proteins at functional quantities into a variety of mammalian cells in the absence of host chromosome modifications. PTNs delivering Manihot esculenta linamarase into rodent or human, tumor cell lines and spheroids mediated hydrolysis of the innocuous natural prodrug linamarin to cyanide and resulted in efficient cell killing. Following linamarin injection into nude mice, linamarase-transducing nanoparticles impacted solid tumor development through the bystander effect of cyanide
Conditional human VEGFâmediated vascularization in chicken embryos using a novel temperatureâinducible gene regulation (TIGR) system
Advanced heterologous transcription control systems for adjusting desired transgene expression are essential for gene function assignments, drug discovery, manufacturing of difficult to produce protein pharmaceuticals and precise dosing of geneâbased therapeutic interventions. Conversion of the Streptomyces albus heat shock response regulator (RheA) into an artificial eukaryotic transcription factor resulted in a vertebrate thermosensor (CTA; coldâinducible transactivator), which is able to adjust transcription initiation from chimeric target promoters (PCTA) in a lowâtemperatureâ inducible manner. Evaluation of the temperatureâdependent CTA-PCTA interaction using a tailored ELISAâlike cellâfree assay correlated increased affinity of CTA for PCTA with temperature downshift. The temperatureâinducible gene regulation (TIGR) system enabled tight repression in the chicken bursal Bâcell line DT40 at 41°C as well as precise titration of model product proteins up to maximum expression at or below 37°C. Implantation of microencapsulated DT40 cells engineered for TIGRâcontrolled expression of the human vascular endothelial growth factor A (hVEGF121) provided lowâtemperatureâinduced VEGFâmediated vascularization in chicken embryo
T-bet negatively regulates autoimmune myocarditis by suppressing local production of interleukin 17
Experimental autoimmune myocarditis (EAM) appears after infectious heart disease, the most common cause of dilated cardiomyopathy in humans. Here we report that mice lacking T-bet, a T-box transcription factor required for T helper (Th)1 cell differentiation and interferon (IFN)-Îł production, develop severe autoimmune heart disease compared to T-betâ/â control mice. Experiments in T-betâ/â IL-4â/â and T-betâ/â IL-4Rαâ/â mice, as well as transfer of heart-specific Th1 and Th2 cell lines, showed that autoimmune heart disease develops independently of Th1 or Th2 polarization. Analysis of T-betâ/â IL-12RÎČ1â/â and T-betâ/â IL-12p35â/â mice then identified interleukin (IL)-23 as critical for EAM pathogenesis. In addition, T-betâ/â mice showed a marked increase in production of the IL-23âdependent cytokine IL-17 by heart-infiltrating lymphocytes, and in vivo IL-17 depletion markedly reduced EAM severity in T-betâ/â mice. Heart-infiltrating T-betâ/â CD8+ but not CD8â T cells secrete IFN-Îł, which inhibits IL-17 production and protects against severe EAM. In contrast, T-betâ/â CD8+ lymphocytes completely lost their capacity to release IFN-Îł within the heart. Collectively, these data show that severe IL-17âmediated EAM can develop in the absence of T-bet, and that T-bet can regulate autoimmunity via the control of nonspecific CD8+ T cell bystander functions in the inflamed target organ
Peanut Can Be Used as a Reference Allergen for Hazard Characterization in Food Allergen Risk Management: A Rapid Evidence Assessment and Meta-Analysis
Regional and national legislation mandates the disclosure of âpriorityâ allergens when present as an ingredient in foods, but this does not extend to the unintended presence of allergens due to shared production facilities. This has resulted in a proliferation of precautionary allergen (âmay containâ) labels (PAL) that are frequently ignored by food-allergic consumers. Attempts have been made to improve allergen risk management to better inform the use of PAL, but a lack of consensus has led to variety of regulatory approaches and nonuniformity in the use of PAL by food businesses. One potential solution would be to establish internationally agreed âreference doses,â below which no PAL would be needed. However, if reference doses are to be used to inform the need for PAL, then it is essential to characterize the hazard associated with these low-level exposures. For peanut, there are now published data relating to over 3000 double-blind, placebo-controlled challenges in allergic individuals, but a similar level of evidence is lacking for other priority allergens. We present the results of a rapid evidence assessment and meta-analysis for the risk of anaphylaxis to a low-level allergen exposure for priority allergens. On the basis of this analysis, we propose that peanut can and should be considered an exemplar allergen for the hazard characterization at a low-level allergen exposure.
Resumen:
La legislaciĂłn regional y nacional exige la divulgaciĂłn de alĂ©rgenos "prioritarios" cuando estĂĄn presentes como ingrediente en los alimentos, pero esto no se extiende a la presencia involuntaria de alĂ©rgenos debido a instalaciones de producciĂłn compartidas. Esto ha dado lugar a una proliferaciĂłn de etiquetas de precauciĂłn para alĂ©rgenos ("pueden contener") (PAL) que los consumidores alĂ©rgicos a los alimentos suelen ignorar. Se han hecho intentos para mejorar la gestiĂłn del riesgo de alĂ©rgenos para informar mejor el uso de PAL, pero la falta de consenso ha llevado a una variedad de enfoques regulatorios y a la falta de uniformidad en el uso de PAL por parte de las empresas alimentarias. Una posible soluciĂłn serĂa establecer âdosis de referenciaâ acordadas internacionalmente, por debajo de las cuales no se necesitarĂa PAL. Sin embargo, si se van a utilizar dosis de referencia para informar la necesidad de PAL, entonces es esencial caracterizar el peligro asociado con estas exposiciones de bajo nivel. Para el manĂ, ahora hay datos publicados relacionados con mĂĄs de 3000 desafĂos doble ciego controlados por placebo en individuos alĂ©rgicos, pero falta un nivel similar de evidencia para otros alĂ©rgenos prioritarios. Presentamos los resultados de una evaluaciĂłn rĂĄpida de la evidencia y un metanĂĄlisis del riesgo deanafilaxia a una exposiciĂłn a alĂ©rgenos de bajo nivel para alĂ©rgenos prioritarios. Sobre la base de este anĂĄlisis, proponemos que el cacahuete puede y debe considerarse un alĂ©rgeno ejemplar para la caracterizaciĂłn del peligro en una exposiciĂłn a un alĂ©rgeno de bajo nivel.Instituto de InvestigaciĂłn de TecnologĂa de AlimentosFil: Turner, Paul J. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Patel, Nandinee. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Ballmer-Weber, Barbara K. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Ballmer-Weber, Barbara K. ClĂnica de DermatologĂa y AlergologĂa. Kantonsspital; Suiza.Fil: Baumert, Joe L. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Blom, W. Marty. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Brooke-Taylor, Simon. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Brough, Helen. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Brough, Helen. King's College London. Departamento de Alergia PediĂĄtrica; Reino Unido.Fil: Campbell, Dianne E. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Campbell, Dianne E. TecnologĂas DBV. Montrouge; Francia.Fil: Chen, Hongbing. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Chinthrajah, R. Sharon. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Crevel, RenĂ© W.R. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Dubois, Anthony E.J. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Ebisawa, Motohiro. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Elizur, Arnon. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Elizur, Arnon. Universidad de Tel Aviv. Facultad de Medicina Sackler. Departamento de PediatrĂa; Israel.Fil: Gerdts, Jennifer D. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Gowland, M. Hazel. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Houben, Geert F. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Hourihane, Jonathan O.B. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Knulst, AndrĂ© C. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: La Vieille, SĂ©bastien. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: LĂłpez, MarĂa Cristina. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Mills, E.N. Clare. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Polenta, Gustavo Alberto. Instituto Nacional de TecnologĂa Agropecuaria (INTA). Instituto de InvestigaciĂłn TecnologĂa de Alimentos; Argentina.Fil: Polenta, Gustavo Alberto. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Purington, Natasha. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Said, MarĂa. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Sampson, Hugh A. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Sampson, Hugh A. Escuela de Medicina Icahn. DivisiĂłn de Alergia e InmunologĂa PediĂĄtricasen. Nueva York. Estados Unidos de AmĂ©rica.Fil: Schnadt, Sabine. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Södergren, Eva. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Södergren, Eva. ThermoFisher Scientific; Suecia.Fil: Taylor, Stephen L. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Remington, Benjamin C. Imperial College London. Instituto Nacional del CorazĂłn y los Pulmones; Reino Unido.Fil: Remington, Benjamin C. Grupo BV. ConsultorĂa Remington; Holanda
A chemical survey of exoplanets with ARIEL
Thousands of exoplanets have now been discovered with a huge range of masses, sizes and orbits: from rocky Earth-like planets to large gas giants grazing the surface of their host star. However, the essential nature of these exoplanets remains largely mysterious: there is no known, discernible pattern linking the presence, size, or orbital parameters of a planet to the nature of its parent star. We have little idea whether the chemistry of a planet is linked to its formation environment, or whether the type of host star drives the physics and chemistry of the planetâs birth, and evolution. ARIEL was conceived to observe a large number (~1000) of transiting planets for statistical understanding, including gas giants, Neptunes, super-Earths and Earth-size planets around a range of host star types using transit spectroscopy in the 1.25â7.8 ÎŒm spectral range and multiple narrow-band photometry in the optical. ARIEL will focus on warm and hot planets to take advantage of their well-mixed atmospheres which should show minimal condensation and sequestration of high-Z materials compared to their colder Solar System siblings. Said warm and hot atmospheres are expected to be more representative of the planetary bulk composition. Observations of these warm/hot exoplanets, and in particular of their elemental composition (especially C, O, N, S, Si), will allow the understanding of the early stages of planetary and atmospheric formation during the nebular phase and the following few million years. ARIEL will thus provide a representative picture of the chemical nature of the exoplanets and relate this directly to the type and chemical environment of the host star. ARIEL is designed as a dedicated survey mission for combined-light spectroscopy, capable of observing a large and well-defined planet sample within its 4-year mission lifetime. Transit, eclipse and phase-curve spectroscopy methods, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allow us to measure atmospheric signals from the planet at levels of 10â100 part per million (ppm) relative to the star and, given the bright nature of targets, also allows more sophisticated techniques, such as eclipse mapping, to give a deeper insight into the nature of the atmosphere. These types of observations require a stable payload and satellite platform with broad, instantaneous wavelength coverage to detect many molecular species, probe the thermal structure, identify clouds and monitor the stellar activity. The wavelength range proposed covers all the expected major atmospheric gases from e.g. H2O, CO2, CH4 NH3, HCN, H2S through to the more exotic metallic compounds, such as TiO, VO, and condensed species. Simulations of ARIEL performance in conducting exoplanet surveys have been performed â using conservative estimates of mission performance and a full model of all significant noise sources in the measurement â using a list of potential ARIEL targets that incorporates the latest available exoplanet statistics. The conclusion at the end of the Phase A study, is that ARIEL â in line with the stated mission objectives â will be able to observe about 1000 exoplanets depending on the details of the adopted survey strategy, thus confirming the feasibility of the main science objectives.Peer reviewedFinal Published versio
Conditional human VEGF-mediated vascularization in chicken embryos using a novel temperature-inducible gene regulation (TIGR) system
Advanced heterologous transcription control systems for adjusting desired transgene expression are essential for gene function assignments, drug discovery, manufacturing of difficult to produce protein pharmaceuticals and precise dosing of gene-based therapeutic interventions. Conversion of the Streptomyces albus heat shock response regulator (RheA) into an artificial eukaryotic transcription factor resulted in a vertebrate thermosensor (CTA; cold-inducible transactivator), which is able to adjust transcription initiation from chimeric target promoters (P(CTA)) in a low-temperature- inducible manner. Evaluation of the temperature-dependent CTAâP(CTA) interaction using a tailored ELISA-like cell-free assay correlated increased affinity of CTA for P(CTA) with temperature downshift. The temperature-inducible gene regulation (TIGR) system enabled tight repression in the chicken bursal B-cell line DT40 at 41°C as well as precise titration of model product proteins up to maximum expression at or below 37°C. Implantation of microencapsulated DT40 cells engineered for TIGR-controlled expression of the human vascular endothelial growth factor A (hVEGF(121)) provided low-temperature-induced VEGF-mediated vascularization in chicken embryos