69 research outputs found

    Coadministration of the Three Antigenic Leishmania infantum Poly (A) Binding Proteins as a DNA Vaccine Induces Protection against Leishmania major Infection in BALB/c Mice

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    Highly conserved intracellular proteins from Leishmania have been described as antigens in natural and experimental infected mammals. The present study aimed to evaluate the antigenicity and prophylactic properties of the Leishmania infantum Poly (A) binding proteins (LiPABPs). Three different members of the LiPABP family have been described. Recombinant tools based on these proteins were constructed: recombinant proteins and DNA vaccines. The three recombinant proteins were employed for coating ELISA plates. Sera from human and canine patients of visceral leishmaniasis and human patients of mucosal leishmaniasis recognized the three LiPABPs. In addition, the protective efficacy of a DNA vaccine based on the combination of the three Leishmania PABPs has been tested in a model of progressive murine leishmaniasis: BALB/c mice infected with Leishmania major. The induction of a Th1-like response against the LiPABP family by genetic vaccination was able to down-regulate the IL-10 predominant responses elicited by parasite LiPABPs after infection in this murine model. This modulation resulted in a partial protection against L. major infection. LiPABP vaccinated mice showed a reduction on the pathology that was accompanied by a decrease in parasite burdens, in antibody titers against Leishmania antigens and in the IL-4 and IL-10 parasite-specific mediated responses in comparison to control mice groups immunized with saline or with the non-recombinant plasmid. The results presented here demonstrate for the first time the prophylactic properties of a new family of Leishmania antigenic intracellular proteins, the LiPABPs. The redirection of the immune response elicited against the LiPABP family (from IL-10 towards IFN-γ mediated responses) by genetic vaccination was able to induce a partial protection against the development of the disease in a highly susceptible murine model of leishmaniasis.The study was supported in Spain by grants from Ministerio de Ciencia e Innovación FIS PI11/00095 and FISPI14/00366 from the Instituto de Salud Carlos III within the Network of Tropical Diseases Research (VI P I+D+I 2008-2011, ISCIII -Subdirección General de Redes y Centros de Investigación Cooperativa (RD12/0018/0009)). This work was also supported in Brazil by a grant from CNPq (Ciencia sem Fronteiras-PVE 300174/2014-4)Peer Reviewe

    Prophylactic properties of a Leishmania-specific hypothetical protein in a murine model of visceral leishmaniasis

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    In this work, the effect of vaccination of a newly described Leishmania infantum antigenic protein has been studied in BALB/c mice infected with this parasite species. The LiHyD protein was characterized after a proteomic screening performed with the sera from dogs suffering visceral leishmaniasis (VL). Its recombinant version was expressed, purified and administered to BALB/c mice in combination with saponin. As a result of vaccination and 10 weeks after challenge using an infective dose of L. infantum stationary promastigotes, vaccinated mice showed lower parasite burdens in different organs (liver, spleen, bone marrow and footpads' draining lymph nodes) than mice inoculated with the adjuvant alone or the vaccine diluent. Protected mice showed anti-Leishmania IgG2a antibodies and a predominant IL-12-driven IFN-γ production (mainly produced by CD4 T cells) against parasite proteins, whereas unprotected controls showed anti-Leishmania IgG1 antibodies and parasite-mediated IL-4 and IL-10 responses. Vaccinated mice showed an anti-LiHyD IgG2a humoral response, and their spleen cells were able to secrete LiHyD-specific IFN-γ, IL-12 and GM-CSF cytokines before and after infection. The protection was correlated with the Leishmania-specific production on nitric oxide. Altogether, the results indicate that the new LiHyD protein could be considered in vaccine formulations against VL.Instituto Nacional de Ci^encia e Tecnologia em Nano-biofarmac^eutica (INCT-NanoBiofar), FAPEMIG (CBB-APQ-00819-12 and CBB-APQ-01778-2014) and CNPq (APQ-482976/2012-8, APQ-488237/2013-0 and APQ-467640/2014-9). In addition, this study was partially funded by the Spanish grant from Ministerio de Economía y Competitividad-FEDER (FIS PI14/00366 from the Instituto de Salud Carlos III)Peer Reviewe

    Inclusion of non-inferiority analysis in superiority-based clinical trials with single-arm, two-stage Simon's design

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    Non-inferiority (NI) analysis is not usually considered in the early phases of clinical development. In some negative phase II trials, a post-hoc NI analysis justified additional phase III trials that were successful. However, the risk of false positive achievements was not controlled in these early phase analyses. We propose to preplan NI analyses in superiority-based Simon's two-stage designs to control type I and II error rates. Simulations have been proposed to assess the control of type I and II errors rates with this method. A total of 12,768 two-stage Simon's design trials were constructed based on different assumptions of rejection response probability, desired response probability, type I and II errors, and NI margins. P-value and type II error were calculated with stochastic ordering using Uniformly Minimum Variance Unbiased Estimator. Type I and II errors were simulated using the Monte Carlo method. The agreement between calculated and simulated values was analyzed with Bland-Altman plots. We observed the same level of agreement between calculated and simulated type I and II errors from both two-stage Simon's superiority designs and designs in which NI analysis was allowed. Different examples has been proposed to explain the utility of this method. Inclusion of NI analysis in superiority-based single-arm clinical trials may be useful for weighing additional factors such as safety, pharmacokinetics, pharmacodynamic, and biomarker data while assessing early efficacy. Implementation of this strategy can be achieved through simple adaptations to existing designs for one-arm phase II clinical trials

    Analysis of the antigenic and prophylactic properties of the Leishmania translation initiation factors eIF2 and eIF2B in natural and experimental leishmaniasis

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    Los diferentes miembros de las familias de proteínas intracelulares son reconocidos por el sistema inmunológico del huésped vertebrado infectado por parásitos del género Leishmania. Aquí hemos analizado las propiedades antigénicas e inmunogénicas de los factores de iniciación de la traducción de Leishmania eIF2 y eIF2B. Una búsqueda in silico en las bases de datos de secuencias de Leishmania infantum permitió la identificación de los genes que codifican las subunidades α, β y γ y las subunidades α, β y δ de los supuestos ortólogos de Leishmania de los factores de iniciación eucarióticos F2 (LieIF2) o F2B (LieIF2B), respectivamente. La antigenicidad de estos factores fue analizada por ELISA utilizando versiones recombinantes de las diferentes subunidades. Se encontraron anticuerpos contra las diferentes subunidades LieIF2 y LieIF2B en los sueros de pacientes con leishmaniosis visceral humana y canina, y también en los sueros de hámsteres infectados experimentalmente con L. infantum. En ratones desafiados por L. infantum (BALB/c) y Leishmania major (BALB/c o C57BL/6) se detectó una respuesta humoral moderada contra estos factores proteicos. Cabe destacar que estas proteínas provocaron una producción de IL-10 por parte de los esplenocitos derivados de ratones infectados, independientemente de la especie de Leishmania empleada para el desafío experimental. Cuando se administraron vacunas de ADN basadas en la expresión de los genes codificantes de las subunidades LieIF2 o LieIF2B en ratones, se observó una secreción específica de antígenos de citoquinas IFN-γ e IL-10. Además, se generó en los ratones vacunados una protección parcial contra el desarrollo de la CL murina debido a la infección por L. major. Además, en este trabajo mostramos que la subunidad LieIF2α y las subunidades LieIF2Bβ y δ tienen la capacidad de estimular la secreción de IL-10 por las células del bazo de los ratones ingenuos. Los linfocitos B fueron identificados como los mayores productores de esta citoquina antiinflamatoria. Teniendo en cuenta los datos encontrados en este estudio, se puede formular la hipótesis de que estas proteínas actúan como factores de virulencia implicados en la inducción de respuestas humorales, así como en la producción de la citoquina IL-10 de regulación descendente, favoreciendo un resultado patológico. Por lo tanto, estas proteínas podrían considerarse marcadores de enfermedad.Different members of intracellular protein families are recognized by the immune system of the vertebrate host infected by parasites of the genus Leishmania. Here, we have analyzed the antigenic and immunogenic properties of the Leishmania eIF2 and eIF2B translation initiation factors. An in silico search in Leishmania infantum sequence databases allowed the identification of the genes encoding the α, β, and γ subunits and the α, β, and δ subunits of the putative Leishmania orthologs of the eukaryotic initiation factors F2 (LieIF2) or F2B (LieIF2B), respectively. The antigenicity of these factors was analyzed by ELISA using recombinant versions of the different subunits. Antibodies against the different LieIF2 and LieIF2B subunits were found in the sera from human and canine visceral leishmaniasis patients, and also in the sera from hamsters experimentally infected with L. infantum. In L. infantum (BALB/c) and Leishmania major (BALB/c or C57BL/6) challenged mice, a moderate humoral response against these protein factors was detected. Remarkably, these proteins elicited an IL-10 production by splenocytes derived from infected mice independently of the Leishmania species employed for experimental challenge. When DNA vaccines based on the expression of the LieIF2 or LieIF2B subunit encoding genes were administered in mice, an antigen-specific secretion of IFN-γ and IL-10 cytokines was observed. Furthermore, a partial protection against murine CL development due to L. major infection was generated in the vaccinated mice. Also, in this work we show that the LieIF2α subunit and the LieIF2Bβ and δ subunits have the capacity to stimulate IL-10 secretion by spleen cells from naïve mice. B-lymphocytes were identified as the major producers of this anti-inflammatory cytokine. Taking into account the data found in this study, it may be hypothesized that these proteins act as virulence factors implicated in the induction of humoral responses as well as in the production of the down-regulatory IL-10 cytokine, favoring a pathological outcome. Therefore, these proteins might be considered markers of disease.• Ministerio de Ciencia e Innovación y Fondos FEDER. Proyectos FISPI14/00366, FISPI14/00366 • Fondo de Investigaciones Sanitarias. Proyecto ISCIII-RETICRD16/0027/0008-FEDER • Conselho Nacional de Desenvolvimento Científico e Tecnológico (Brasil). Program 300174/2014-4 • Centro de Biología Molecular Severo Ochoa. Ayuda • Fundación Ramón Areces. Ayuda • Banco de Santander. AyudapeerReviewe

    Coadministration of the three antigenic Leishmania infantum poly (A) binding proteins as a DNA vaccine induces protection against Leishmania major infection in BALB/c Mice

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    Antecedentes Las proteínas intracelulares de Leishmania, altamente conservadas, han sido descritas como antígenos en mamíferos infectados natural y experimentalmente. El objetivo del presente estudio es evaluar la antigenicidad y propiedades profilácticas del Leishmania infantum Poly (A) las proteínas (LiPABPs). Metodología/Resultados principales Se han descrito tres diferentes miembros de la familia LiPABP. Se han elaborado herramientas recombinantes basadas en estas proteínas: proteínas recombinantes y vacunas de ADN. Las tres proteínas recombinantes fueron empleadas para recubrir las placas ELISA. Los sueros de pacientes humanos y caninos de leishmaniasis visceral y de pacientes humanos de leishmaniasis mucosa han reconoció los tres LiPABPs. Además, la eficacia protectora de la vacuna de ADN basada en la combinación de los tres Leishmania PABPs ha sido probado en un modelo murino de leishmaniosis progresiva: ratones BALB/c infectados con Leishmania major. La inducción de Th1 como respuesta contra la familia LiPABP por vacunación génica fue capaz de regular a la baja la IL-10 con respuestas predominantes suscitadas por el parásito LiPABPs tras la infección en este modelo murino. Esta modulación se tradujo en una protección parcial contra la infección por L. major. Los ratones vacunados con LiPABP mostraron una reducción de la patología que fue acompañada por una disminución de la carga parasitaria, en títulos de anticuerpos contra antígenos de Leishmania y de la IL-4 y la IL-10 las respuestas mediadas específicas del parásito en comparación con el control de grupos de ratones inmunizados con solución salina o con no-plásmidos recombinantes. Conclusión/significación Los resultados aquí presentados demuestran por primera vez las propiedades profilácticas de una nueva familia de proteínas intracelulares antigénicas de Leishmania, la LiPABPs. La redirección de la respuesta inmune desencadenada frente contra la familia LiPABP (de IL-10 hacia las respuestas mediadas por IFN-γ) por vacunación génica fue capaz de inducir una protección parcial contra el desarrollo de la enfermedad en un modelo murino altamente susceptible de leishmaniasis.Background Highly conserved intracellular proteins from Leishmania have been described as antigens in natural and experimental infected mammals. The present study aimed to evaluate the antigenicity and prophylactic properties of the Leishmania infantum Poly (A) binding proteins (LiPABPs). Methodology/Principal Findings Three different members of the LiPABP family have been described. Recombinant tools based on these proteins were constructed: recombinant proteins and DNA vaccines. The three recombinant proteins were employed for coating ELISA plates. Sera from human and canine patients of visceral leishmaniasis and human patients of mucosal leishmaniasis recognized the three LiPABPs. In addition, the protective efficacy of a DNA vaccine based on the combination of the three Leishmania PABPs has been tested in a model of progressive murine leishmaniasis: BALB/c mice infected with Leishmania major. The induction of a Th1-like response against the LiPABP family by genetic vaccination was able to down-regulate the IL-10 predominant responses elicited by parasite LiPABPs after infection in this murine model. This modulation resulted in a partial protection against L. major infection. LiPABP vaccinated mice showed a reduction on the pathology that was accompanied by a decrease in parasite burdens, in antibody titers against Leishmania antigens and in the IL-4 and IL-10 parasite-specific mediated responses in comparison to control mice groups immunized with saline or with the non-recombinant plasmid. Conclusion/Significance The results presented here demonstrate for the first time the prophylactic properties of a new family of Leishmania antigenic intracellular proteins, the LiPABPs. The redirection of the immune response elicited against the LiPABP family (from IL-10 towards IFN-γ mediated responses) by genetic vaccination was able to induce a partial protection against the development of the disease in a highly susceptible murine model of leishmaniasis.• Ministerio de Ciencia e Innovación. Proyectos FISPI14/00366 y FISPI11/00095 del Instituto de Salud Carlos III dentro de la Red de Investigación de Enfermedades Tropicales. Proyecto VI P I D I 2008-2011, ISCIII - Subdirección General de Redes y Centros de Investigación Cooperativa (RD12/0018/0009) • CNPq (Ciencia sem Fronteiras), Brasil: PVE 300174/2014-4 • Fundación Ramón Areces: Subvenciones al Centro de Biología Molecular Severo Ochoa (CBMSO).peerReviewe

    Latent class analysis-based subgroups and response to corticosteroids in hospitalised community-acquired pneumonia patients: a validation study

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    In patients with community-acquired pneumonia, LCA can identify robust prognostic subgroups based on clinical and inflammatory parameters. Yet, these subgroups have not proven robust in predicting response to adjunctive dexamethasone treatment. https://bit.ly/3O5eaxz

    Coadministration of the Three Antigenic Leishmania infantum Poly (A) Binding Proteins as a DNA Vaccine Induces Protection against Leishmania major Infection in BALB/c Mice

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    Highly conserved intracellular proteins from Leishmania have been described as antigens in natural and experimental infected mammals. The present study aimed to evaluate the antigenicity and prophylactic properties of the Leishmania infantum Poly (A) binding proteins (LiPABPs). Three different members of the LiPABP family have been described. Recombinant tools based on these proteins were constructed: recombinant proteins and DNA vaccines. The three recombinant proteins were employed for coating ELISA plates. Sera from human and canine patients of visceral leishmaniasis and human patients of mucosal leishmaniasis recognized the three LiPABPs. In addition, the protective efficacy of a DNA vaccine based on the combination of the three Leishmania PABPs has been tested in a model of progressive murine leishmaniasis: BALB/c mice infected with Leishmania major. The induction of a Th1-like response against the LiPABP family by genetic vaccination was able to down-regulate the IL-10 predominant responses elicited by parasite LiPABPs after infection in this murine model. This modulation resulted in a partial protection against L. major infection. LiPABP vaccinated mice showed a reduction on the pathology that was accompanied by a decrease in parasite burdens, in antibody titers against Leishmania antigens and in the IL-4 and IL-10 parasite-specific mediated responses in comparison to control mice groups immunized with saline or with the non-recombinant plasmid. The results presented here demonstrate for the first time the prophylactic properties of a new family of Leishmania antigenic intracellular proteins, the LiPABPs. The redirection of the immune response elicited against the LiPABP family (from IL-10 towards IFN-γ mediated responses) by genetic vaccination was able to induce a partial protection against the development of the disease in a highly susceptible murine model of leishmaniasisThe study was supported in Spain by grants from Ministerio de Ciencia e Innovación FIS PI11/00095 and FISPI14/00366 from the Instituto de Salud Carlos III within the Network of TropicalDiseases Research (VI P I+D+I 2008-2011, ISCIII -Subdirección General de Redes y Centros de Investigación Cooperativa (RD12/0018/0009)). This work was also supported in Brazil by a grant from CNPq (Ciencia sem Fronteiras-PVE 300174/2014-4). A CBMSO institutional grant from Fundación Ramón Areces is also acknowledged. EAFC is a grant recipient of CNPq. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscrip

    Nutrición parenteral domiciliaria en España, 2019: informe del Grupo de Nutrición Artificial Domiciliaria y Ambulatoria NADYA

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    RESUMEN Objetivo: comunicar los datos de nutrición parenteral domiciliaria (NPD) obtenidos del registro del grupo NADYA-SENPE (www.nadyasenpe.com) del año 2019. Material y métodos: análisis descriptivo de los datos recogidos de pacientes adultos y pediátricos con NPD en el registro NADYA-SENPE desde el 1 de enero al 31 de diciembre de 2019. Resultados: se registraron 283 pacientes (51,9 %, mujeres), 31 niños y 252 adultos procedentes de 47 hospitales españoles, lo que representa una tasa de prevalencia de 6,01 pacientes/millón de habitantes/año 2019. El diagnóstico más frecuente en los adultos fue “oncológico paliativo” y “otros” (21,0 %). En los niños fue la enfermedad de Hirschsprung junto a la enterocolitis necrotizante, las alteraciones de la motilidad intestinal y la pseudoobstrucción intestinal crónica, con 4 casos cada uno (12,9 %). El primer motivo de indicación fue el síndrome del intestino corto tanto en los niños (51,6 %) como en los adultos (37,3 %). El tipo de catéter más utilizado fue el tunelizado tanto en los niños (75,9 %) como en los adultos (40,8 %). Finalizaron 68 episodios, todos en adultos: la causa más frecuente fue el fallecimiento (54,4 %). Pasaron a la vía oral el 38,2 %. Conclusiones: el número de centros y profesionales colaboradores con el registro NADYA va incrementándose. Se mantienen estables las principales indicaciones y los motivos de finalización de la NPD

    Identification of genetic variants associated with Huntington's disease progression: a genome-wide association study

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    Background Huntington's disease is caused by a CAG repeat expansion in the huntingtin gene, HTT. Age at onset has been used as a quantitative phenotype in genetic analysis looking for Huntington's disease modifiers, but is hard to define and not always available. Therefore, we aimed to generate a novel measure of disease progression and to identify genetic markers associated with this progression measure. Methods We generated a progression score on the basis of principal component analysis of prospectively acquired longitudinal changes in motor, cognitive, and imaging measures in the 218 indivduals in the TRACK-HD cohort of Huntington's disease gene mutation carriers (data collected 2008–11). We generated a parallel progression score using data from 1773 previously genotyped participants from the European Huntington's Disease Network REGISTRY study of Huntington's disease mutation carriers (data collected 2003–13). We did a genome-wide association analyses in terms of progression for 216 TRACK-HD participants and 1773 REGISTRY participants, then a meta-analysis of these results was undertaken. Findings Longitudinal motor, cognitive, and imaging scores were correlated with each other in TRACK-HD participants, justifying use of a single, cross-domain measure of disease progression in both studies. The TRACK-HD and REGISTRY progression measures were correlated with each other (r=0·674), and with age at onset (TRACK-HD, r=0·315; REGISTRY, r=0·234). The meta-analysis of progression in TRACK-HD and REGISTRY gave a genome-wide significant signal (p=1·12 × 10−10) on chromosome 5 spanning three genes: MSH3, DHFR, and MTRNR2L2. The genes in this locus were associated with progression in TRACK-HD (MSH3 p=2·94 × 10−8 DHFR p=8·37 × 10−7 MTRNR2L2 p=2·15 × 10−9) and to a lesser extent in REGISTRY (MSH3 p=9·36 × 10−4 DHFR p=8·45 × 10−4 MTRNR2L2 p=1·20 × 10−3). The lead single nucleotide polymorphism (SNP) in TRACK-HD (rs557874766) was genome-wide significant in the meta-analysis (p=1·58 × 10−8), and encodes an aminoacid change (Pro67Ala) in MSH3. In TRACK-HD, each copy of the minor allele at this SNP was associated with a 0·4 units per year (95% CI 0·16–0·66) reduction in the rate of change of the Unified Huntington's Disease Rating Scale (UHDRS) Total Motor Score, and a reduction of 0·12 units per year (95% CI 0·06–0·18) in the rate of change of UHDRS Total Functional Capacity score. These associations remained significant after adjusting for age of onset. Interpretation The multidomain progression measure in TRACK-HD was associated with a functional variant that was genome-wide significant in our meta-analysis. The association in only 216 participants implies that the progression measure is a sensitive reflection of disease burden, that the effect size at this locus is large, or both. Knockout of Msh3 reduces somatic expansion in Huntington's disease mouse models, suggesting this mechanism as an area for future therapeutic investigation

    Mecanismos bioquimicos de accion de un nuevo antagonista de PAF, PCA-4248, en plaquetas

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    Centro de Informacion y Documentacion Cientifica (CINDOC). C/Joaquin Costa, 22. 28002 Madrid. SPAIN / CINDOC - Centro de Informaciòn y Documentaciòn CientìficaSIGLEESSpai
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