32 research outputs found

    Evaluación preliminar del poder antigénico in vivo de una nueva formulación para la inmunoprofilaxis de la babesiosis bovina

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    Bovine babesiosis is a hemoparasitic disease caused by protozoa of the genus Babesia, the most important are Babesia bovis and B. bigemina, both transmitted by the common bovine tick, Rhipicephalus microplus. In combination with anaplasmosis, they form the Bovine Tristeza Complex, one of the main limiting factors for productive development in tropical and subtropical areas of the world. Currently, for the prophylaxis of bovine babesiosis in Argentina, only live vaccines are available in fresh and deep-frozen presentations. In the present work, we evaluated the immunogenicity of erythrocytes parasitized with Babesia sp, dehydrated and incorporated into a new adjuvant, formulated for use in humans, as a new immuno prophylactic alternative. With this aim, parasitized erythrocytes obtained from in vitro cultures were dehydrated by spray-dryingtechniques and assembled with an adjuvant. Twelve calves negative for blood parasites wereused, which were divided into 4 groups of 3 animals each one. Control group: without inoculation;Treated Group 1: inoculated with adjuvant; Treated Group 2: adjuvant + erythrocytes parasitized with B. bovis and Treated Group 3: adjuvant + erythrocytes parasitized with B. bigemina. Two subcutaneous inoculations were performed, on 0 and 15 days. During 60 days, rectal temperature, hematocrit and parasitaemia control were performed, in turn, samples for serology were taken on 30- and 60-days post inoculation. The animals remained negative throughout the trial, except on day 60, where 33% of Treated Group 3 presented specific antibody titers against the inoculated agent, B. bigemina. Although the response rate is low, the fact that there is no effective killed vaccine for the prophylaxis of this disease encourages us to continue adjusting the inoculant dose.La babesiosis bovina es una enfermedad hemoparasitaria causada por protozoarios del gĂ©nero Babesia, siendo los de mayor importancia Babesia bovis y B. bigemina, ambos transmitidos por la garrapata comĂșn del bovino, Rhipicephalus microplus. Junto con la anaplasmosis, forman el complejo tristeza bovina, uno de los principales factores limitantes para el desarrollo productivo en zonas tropicales y subtropicales del mundo. Actualmente, para la profilaxis de la babesiosis bovina en Argentina solo se dispone de vacunas vivas en las presentaciones, fresca y ultra congelada. En el presente trabajo, se evaluĂł la inmunogenicidad de eritrocitos parasitados con Babesia sp y deshidratados, incorporados a un nuevo adyuvante, formulado para uso en humanos, como una nueva alternativa inmuno profilĂĄctica. Con tal fin, eritrocitos parasitados obtenidos a partir de cultivos in vitro, fueron deshidratados por tĂ©cnicas de secado por aspersiĂłn y ensamblados con un adyuvante. Se utilizaron 12 terneros negativos a hemoparĂĄsitos que fueron distribuidos en 4 grupos de 3 animales cada uno. Grupo Control: sin inocular; Grupo Tratado 1: inoculado con adyuvante; Grupo Tratado 2: adyuvante + eritrocitos parasitados con B. bovis y Grupo Tratado 3: adyuvante + eritrocitos parasitados con B. bigemina. Se realizaron dos inoculaciones subcutĂĄneas, los dĂ­as 0 y 15. Durante 60 dĂ­as, se realizĂł el control de temperatura rectal, hematocrito y parasitemia, asĂ­ como el muestreo para serologĂ­a a los 30 y 60 dĂ­as post-inoculaciĂłn. Los animales se mantuvieron negativos durante todo el ensayo, excepto al dĂ­a 60, donde el 33% del Grupo Tratado 3 presentĂł titulaciĂłn de anticuerpos contra el agente inoculado, B. bigemina. Si bien el porcentaje de respuesta es bajo, el hecho de no contar a nivel mundial con una vacuna muerta eficaz para la profilaxis de esta enfermedad, nos alienta a continuar ajustando la dosis inoculante

    Class-B CpG-ODN formulated with a nanostructure induces type I interferons-dependent and CD4+T cell-independent CD8+T-Cell response against unconjugated protein antigen

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    There is a need for new vaccine adjuvant strategies that offer both vigorous antibody and T-cell mediated protection to combat difficult intracellular pathogens and cancer. To this aim, we formulated class-B synthetic oligodeoxynucleotide containing unmethylated cytosine-guanine motifs (CpG-ODN) with a nanostructure (Coa-ASC16 or coagel) formed by self-assembly of 6-0-ascorbyl palmitate ester. Our previous results demonstrated that mice immunized with ovalbumin (OVA) and CpG-ODN formulated with Coa-ASC16 (OVA/CpG-ODN/Coa-ASC16) elicited strong antibodies (IgG1 and IgG2a) and Th1/Th17 cellular responses without toxic systemic effects. These responses were superior to those induced by a solution of OVA with CpG-ODN or OVA/CpG-ODN formulated with aluminum salts. In this study, we investigated the capacity of this adjuvant strategy (CpG-ODN/Coa-ASC16) to elicit CD8+ T-cell response and some of the underlying cellular and molecular mechanisms involved in adaptive response. We also analyzed whether this adjuvant strategy allows a switch from an immunization scheme of three-doses to one of single-dose. Our results demonstrated that vaccination with OVA/CpG-ODN/Coa-ASC16 elicited an antigen-specific long-lasting humoral response and importantly-high quality CD8+ T-cell immunity with a single-dose immunization. Moreover, Coa-ASC16 promoted co-uptake of OVA and CpG-ODN by dendritic cells. The CD8+ T-cell response induced by OVA/CpG-ODN/Coa-ASC16 was dependent of type I interferons and independent of CD4+ T-cells, and showed polyfunctionality and efficiency against an intracellular pathogen. Furthermore, the cellular and humoral responses elicited by the nanostructured formulation were IL-6-independent. This system provides a simple and inexpensive adjuvant strategy with great potential for future rationally designed vaccines.Fil: Chiodetti, Ana Laura. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; ArgentinaFil: Sånchez Vallecillo, María Fernanda. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; ArgentinaFil: Dolina, Joseph S.. La Jolla Institute for Allergy and Immunology; Estados UnidosFil: Crespo, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica; ArgentinaFil: Marin, Constanza. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica; ArgentinaFil: Schoenberger, Stephen P.. La Jolla Institute for Allergy and Immunology; Estados UnidosFil: Allemandi, Daniel Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; ArgentinaFil: Palma, Santiago Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; ArgentinaFil: Pistoresi, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica; ArgentinaFil: Moron, Victor Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica; ArgentinaFil: Maletto, Belkys Angélica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica; Argentin

    Class-B CpG-ODN Formulated With a Nanostructure Induces Type I Interferons-Dependent and CD4+ T Cell-Independent CD8+ T-Cell Response Against Unconjugated Protein Antigen

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    There is a need for new vaccine adjuvant strategies that offer both vigorous antibody and T-cell mediated protection to combat difficult intracellular pathogens and cancer. To this aim, we formulated class-B synthetic oligodeoxynucleotide containing unmethylated cytosine-guanine motifs (CpG-ODN) with a nanostructure (Coa-ASC16 or coagel) formed by self-assembly of 6-0-ascorbyl palmitate ester. Our previous results demonstrated that mice immunized with ovalbumin (OVA) and CpG-ODN formulated with Coa-ASC16 (OVA/CpG-ODN/Coa-ASC16) elicited strong antibodies (IgG1 and IgG2a) and Th1/Th17 cellular responses without toxic systemic effects. These responses were superior to those induced by a solution of OVA with CpG-ODN or OVA/CpG-ODN formulated with aluminum salts. In this study, we investigated the capacity of this adjuvant strategy (CpG-ODN/Coa-ASC16) to elicit CD8+ T-cell response and some of the underlying cellular and molecular mechanisms involved in adaptive response. We also analyzed whether this adjuvant strategy allows a switch from an immunization scheme of three-doses to one of single-dose. Our results demonstrated that vaccination with OVA/CpG-ODN/Coa-ASC16 elicited an antigen-specific long-lasting humoral response and importantly-high quality CD8+ T-cell immunity with a single-dose immunization. Moreover, Coa-ASC16 promoted co-uptake of OVA and CpG-ODN by dendritic cells. The CD8+ T-cell response induced by OVA/CpG-ODN/Coa-ASC16 was dependent of type I interferons and independent of CD4+ T-cells, and showed polyfunctionality and efficiency against an intracellular pathogen. Furthermore, the cellular and humoral responses elicited by the nanostructured formulation were IL-6-independent. This system provides a simple and inexpensive adjuvant strategy with great potential for future rationally designed vaccines

    Baculovirus Capsid Display Potentiates OVA Cytotoxic and Innate Immune Responses

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    Baculoviruses (BV) are DNA viruses that are pathogenic for insects. Although BV infect a range of mammalian cell types, they do not replicate in these cells. Indeed, the potential effects of these insect viruses on the immune responses of mammals are only just beginning to be studied. We show in this paper that a recombinant Autographa californica multiple nuclear polyhedrosis virus carrying a fragment of ovalbumin (OVA) on the VP39 capsid protein (BV-OVA) has the capacity to act as an adjuvant and vector of antigens in mice, thereby promoting specific CD4 and cytotoxic T cell responses against OVA. BV also induced in vivo maturation of dendritic cells and the production of inflammatory cytokines, thus promoting innate and adaptive immune responses. The OVA-specific response induced by BV-OVA was strong enough to reject a challenge with OVA-expressing melanoma cells (MO5 cells) and effectively prolonged survival of MO5 bearing mice. All these findings, together with the absence of pre-existing immunity to BV in humans and the lack of viral gene expression in mammalian cells, make BV a candidate for vaccination

    FcRn Overexpression in Transgenic Mice Results in Augmented APC Activity and Robust Immune Response with Increased Diversity of Induced Antibodies

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    Our previous studies have shown that overexpression of bovine FcRn (bFcRn) in transgenic (Tg) mice leads to an increase in the humoral immune response, characterized by larger numbers of Ag-specific B cells and other immune cells in secondary lymphoid organs and higher levels of circulating Ag-specific antibodies (Abs). To gain additional insights into the mechanisms underlying this increase in humoral immune response, we further characterized the bFcRn Tg mice. Our Western blot analysis showed strong expression of the bFcRn transgene in peritoneal macrophages and bone marrow derived dendritic cells; and a quantitative PCR analysis demonstrated that the expression ratios of the bFcRn to mFcRn were 2.6- and 10-fold in these cells, respectively. We also found that overexpression of bFcRn enhances the phagocytosis of Ag-IgG immune complexes (ICs) by both macrophages and dendritic cells and significantly improves Ag presentation by dendritic cells. Finally, we determined that immunized bFcRn mice produce a much greater diversity of Ag-specific IgM, whereas only the levels, but not the diversity, of IgG is increased by overexpression of bFcRn. We suggest that the increase in diversity of IgG in Tg mice is prevented by a selective bias towards immunodominant epitopes of ovalbumin, which was used in this study as a model antigen. These results are also in line with our previous reports describing a substantial increase in the levels of Ag-specific IgG in FcRn Tg mice immunized with Ags that are weakly immunogenic and, therefore, not affected by immunodominance

    The Road Less Traveled: Regulation of Leukocyte Migration Across Vascular and Lymphatic Endothelium by Galectins

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    Leukocyte entry from the blood into inflamed tissues, exit into the lymphatics, and migration to regional lymph nodes are all crucial processes for mounting an effective adaptive immune response. Leukocytes must cross two endothelial cell layers, the vascular and the lymphatic endothelial cell layers, during the journey from the blood to the lymph node. The proteins and cellular interactions which regulate leukocyte migration across the vascular endothelium are well studied; however, little is known about the factors that regulate leukocyte migration across the lymphatic endothelium. Here, we will summarize evidence for a role for galectins, a family of carbohydrate-binding proteins, in regulating leukocyte migration across the vascular endothelium and propose that galectins are also involved in leukocyte migration across the lymphatic endothelium

    Maladie de la hyÚne et carences minérales

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    The authors have studied the mineral composition of bone and hair of cattle suffering from «Hyena Disease». The results have been compared with the results of the analysis carried out on cattle of the same breed, age, system of nutrition and living in the same environment. The results confirm the observations of Adam et al. (1981) about the decrease of Ni, Cu and Mn, the slight increase of Zn and Fe, and show besides, in the calcinated bone, a considerable increase of P and of K. These changes do not seem caused by an insufficient diet, but rather by metabolic troubles. Therefore, the «Hyena Disease» should be listed among the morpho-osteo-distrophic osteopaties.Les auteurs ont Ă©tudiĂ© la composition minĂ©rale de l'os et des poils chez des bovins atteints de la Maladie de la HyĂšne (M.H.). Us ont comparĂ© les rĂ©sultats avec ceux obtenus chez des animaux tĂ©moins de mĂȘme race, du mĂȘme Ăąge, recevant la mĂȘme alimentation et entretenus dans le mĂȘme Ă©levage. Les rĂ©sultats obtenus confirment ceux de Adam et al. (1981) en ce qui concerne la rĂ©duction de la concentration de nickel, de cuivre et de manganĂšse, la faible augmentation du zinc et du fer et dans les cendres d'os, une Ă©lĂ©vation remarquable du phosphore et de façon plus limitĂ©e du potassium. La discussion de ces rĂ©sultats incite Ă  rapporter les altĂ©rations observĂ©es Ă  un trouble mĂ©tabolique plutĂŽt qu'Ă  une carence nutritionnelle. La M.H. devrait donc ĂȘtre considĂ©rĂ©e comme une ostĂ©opathie morpho-ostĂ©o-dystrophique.Ballarini G., Maletto S. Maladie de la hyĂšne et carences minĂ©rales. In: Bulletin de l'AcadĂ©mie VĂ©tĂ©rinaire de France tome 136 n°2, 1983. pp. 227-234
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