Technological platform for research and development of vaccines against leishmaniasis

La leishmaniasis es un grupo de enfermedades parasitarias endémicas en la República Argentina, causadas por protozoarios intracelulares del género Leishmania. Uno de los principales agentes etiológicos de amplio espectro en la presentaciones clínicas, es Leishmania (Leishmania) amazonensis, con una amplia distribución geográfica en el continente Americano, y en el Norte de Argentina. En el hospedador vertebrado la resistencia a la infección contra protozoos del género Leishmania está dada por la inmunidad celular, en especial por la activación de los macrófagos por citoquinas sintetizadas por los linfocitos Th1. Las células del perfil Th1 secretan principalmente IL-2 e IFN-g;, mientras que las células del perfil Th2 secretan IL-4, IL-5 e IL-10. Se ha demostrado que el IFN-g; activa los macrófagos, generando la expresión de iNOS, enzima que cataliza la formación de NO, necesario para la destrucción de los amastigotes intracelulares. Por el contrario, una respuesta inmune del tipo Th2 limita la acción Th1 a través de las funciones de la IL-10 e IL-4, que desactivan a los macrófagos permitiendo el crecimiento intracelular del parásito y progresión de la enfermedad. El objetivo general del proyecto es el desarrollo y optimización de nuevas formulaciones vacunales de primera generación, basadas en antígenos totales del género Leishmania, que sean capaces de generar inmunidad humoral y celular protectora frente a la infección por L. (L.) amazonensis en un modelo murino. Por lo tanto se producirán antígenos totales de L. (L.) amazonensis (ATL). Posteriormente se ensayaran en ratones BALB/c, protocolos de inmunización con una formulación vacunal basada en ATL, en combinación con Poly (I:C) y c-di-AMP como adyuvantes. Finalizados los protocolos de inmunización se evaluara la respuesta inmune humoral y celular. La formulación vacunal que haya logrado una optima activación del sistema inmune, se ensayara, para evaluar la protección conferida en los animales de experimentación, contra el desafío de formas infectantes de L. (L.) amazonensis. Además, el presente proyecto tiene como objetivo identificar antígenos inmunodominantes en extractos proteicos de promastigote de L. (L.) amazonensis, mediante el empleo de técnicas de inmunoproteómica, empleando suero de animales inmunizados con antígenos totales de L. (L.) amazonensis formulados en conjunto con una emulsión agua en aceite y un agonista de TLR como adyuvantes.Leishmaniasis is a group of endemic parasitic diseases in the Argentine Republic, caused by intracellular protozoa of the genus Leishmania. One of the main etiologic agents of broad spectrum in the clinical presentations, is Leishmania (Leishmania) amazonensis, with a wide geographic distribution in the American continent, and in the North of Argentina. Resistance against the infection with Leishmania protozoa is given by cellular immunity, especially through the activation of macrophages with citokynes synthesized by Th1 lymphocites. Th1 cells secrete mainly IL-2 and IFN-g, while Th2 cells secrete IL-4, IL-5 and IL-10. It has been demonstrated that IFN-g; activates macrophages, generating the expression of iNOS, enzyme that catalyzes the formation of NO, necessary for the destruction of the intracellular amastigotes. On the contrary, a type Th2 immune response limits the Th1 action through the functions of IL-10 and IL-4, which deactivate the macrophages allowing the intracellular growth of the parasite and the progression of the disease. The main objective of the project is the development and optimization of a first generation vaccine against leishmaniasis based on total Leishmania antigens, capable of generating humoral and cellular protective immunity against L. (L.) amazonensis infection in a murine model. Thus, total antigens (ATL) from L. (L.) amazonensis will be produced and they will be essayed on BALB/c mice in vaccination protocols, combined Poly (I:C) with c-di-AMP as adjuvant. Once the vaccinations protocols are finished, the humoral and cellular response will be evaluated. The vaccine formulation that reaches an optimal activation of the immune system will be essayed to evaluate the given protection on animals for experimentation against the challenge of infecting forms of L. (L.) amazonensis. In addition, the present study aims to identify immunodominant antigens in protein extracts of L. (L.) amazonensis promastigote, using immunoproteomics techniques, using sera from animals immunized with total antigens of L. (L.) amazonensis formulated in conjunction with a water-in-oil emulsion and a TLR agonist as adjuvants

Dissemination of visceral leishmaniasis to Western Argentina: When will imported canine vector-borne zoonotic diseases start being local?

Fil: Mera y Sierra, Roberto. Universidad "Juan Agustín Maza". Facultad de Ciencias Veterinarias y Ambientales. Centro de Investigación en Parasitología Regional; ArgentinaFil: Neira, Gisela Natalia. Universidad "Juan Agustín Maza". Facultad de Ciencias Veterinarias y Ambientales. Centro de Investigación en Parasitología Regional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cargnelutti, Diego Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin

Human diphyllobothriosis: A case in a non-endemic area of Argentina

La difilobotriosis es una parasitosis intestinal causada por la infección de cestodos del genero Diphyllobothrium. En la Argentina, la Patagonia Andina es considerada una zona endémica para esta parasitosis. La infección por Diphyllobothrium latum no ha sido previamente notificada en la provincia de Mendoza; en este trabajo comunicamos un caso de esta parasitosis que fue confirmada por el análisis de las características morfológicas de los huevos eliminados con la materia fecal de un paciente infectado. Se destaca la necesidad de información y capacitación de los profesionales de la salud en el diagnóstico y tratamiento de parasitosis no endémicas.Diphyllobothriosis is an intestinal parasitosis caused by cestodes infection of the genus Diphyllobothrium. In Argentina, the Andean Patagonia is considered an endemic area for this parasitosis. Diphyllobothrium latum infection has not been previously reported in the province of Mendoza, Argentina. We are now reporting then the first case. Diphyllobothriosis was confirmed by examination of morphologic characteristics of the eggs eliminated in the patients’ feces. These results suggest the requirement of a more specific training of health workers in the diagnosis and treatment of non endemic parasitosis. We want to emphasize the need of health workers’ education on diagnosis and treatment of endemic and non-endemic parasitosis.Fil: Cargnelutti, Diego Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; ArgentinaFil: Salomón, María Cristina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; Argentin

Development of a universa CTL-based vaccine for influenza

In pursuit of better influenza vaccines, many strategies are being studied worldwide. An attractive alternative is the generation of a broadly cross-reactive vaccine based on the induction of cytotoxic T-lymphocytes (CTL) directed against conserved internal antigens of influenza A virus. The feasibility of this approach using recombinant viral vectors has recently been demonstrated in mice and humans by several research groups. However, similar results might also be achieved through immunization with viral proteins expressed in a prokaryotic system formulated with the appropriate adjuvants and delivery systems. This approach would be much simpler and less expensive. Recent results from several laboratories seem to confirm this is as a valid option to be considered.Fil: Cargnelutti, Diego Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Sánchez, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Mattion, Nora Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Scodeller, Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin

Therapeutic effect of Prosopis strombulifera (LAM) BENTH aqueous extract on a murine model of cutaneous leishmaniasis

Background and aim: Prosopis strombulifera (Lam.) Benth is a rhizomatous shrub native from different zones of Argentine Republic. P. strombulifera aqueous extract (PsAE) has different effects and several biological activities have been reported. The goal of this study was to analyze the activity of PsAE on a murine model of cutaneous leishmaniasis caused by Leishmania amazonensis. Experimental procedure: PsAE was orally administered at 150 mg/animal/day on BALB/c mice infected in the right footpad (RFP) with 1 × 105 promastigotes of L. amazonensis. As a chemotherapeutic control of treatment, animals receive a commercial form of meglumine antimoniate (MA) (Glucantime®, Aventis, Paris, France). Results and conclusion: We observe that the size of RFP lesions of infected mice without treatment showed a grade of inflammation, ulceration and necrosis at the site of infection much greater than that observed with PsAE or MA treatment. Moreover, PsAE was capable of decreasing parasite burden and splenic index. Furthermore, PsAE treated mice showed a significant decrease in O.D. of total anti-Leishmania IgG antibody responses against L. amazonensis. This decrease was similar to those observed when the reference drug, MA, was used. This would indicate that PsAE treatment inhibits or delays disease progression in mice. In conclusion, our findings suggest that PsAE could be a potential candidate to be used, as a new therapeutic strategy, to treat cutaneous leishmaniasis caused by L. amazonensis.Fil: Lozano, Esteban Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Germano, Maria Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Troncoso, Mariana Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad de Mendoza; ArgentinaFil: Garcia Bustos, Maria Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Patología Experimental. Universidad Nacional de Salta. Facultad de Ciencias de la Salud. Instituto de Patología Experimental; ArgentinaFil: Gamarra Luques, Carlos Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Cargnelutti, Diego Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin

Immunization with antigenic extracts of Leishmania associated with Montanide ISA 763 adjuvant induces partial protection in BALB/c mice against Leishmania (Leishmania) amazonensis infection

Background/Purpose: A proper adjuvant has a relevant role in vaccine formulations to generate an effective immune response. In this study, total Leishmania antigen (TLA) formulated with Montanide ISA 763 or R848 as adjuvants were evaluated as a first generation Leishmania vaccine in a murine model. Methods: Immunization protocols were tested in BALB/c mice with a subcutaneous prime/boost regimen with an interval of 3 weeks. Mice immunized with unadjuvanted TLA and phosphate-buffered saline (PBS) served as control groups. On Day 21 and Day 36 of the protocol, we evaluated the humoral immune response induced by each formulation. Fifteen days after the boost, the immunized mice were challenged with 1 × 105 promastigotes of Leishmania (Leishmania) amazonensis in the right footpad (RFP). The progress of the infection was followed for 10 weeks; at the end of this period, histopathological studies were performed in the RFP. Results: Vaccines formulated with Montanide ISA 763 generated an increase in the production of immunoglobulin G (IgG; p < 0.05) compared with the control group. There were no statistically significant differences in IgG1 production between the study groups. However, immunization with TLA-Montanide ISA 763 resulted in an increase in IgG2a compared to the unadjuvanted control (p < 0.001). Also noteworthy was the fact that a significant reduction in swelling and histopathological damage of the RFP was recorded with the Montanide ISA 763 formulation. Conclusion: We conclude that the immunization of BALB/c mice with a vaccine formulated with TLA and Montanide ISA 763 generated a protective immune response against L. (L.) amazonensis, characterized by an intense production of IgG2a.Fil: Cargnelutti, Diego Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo; ArgentinaFil: Salomón, María Cristina. Universidad Nacional de Cuyo; ArgentinaFil: Celedon, Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Garcia Bustos, Maria Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Patología Experimental. Universidad Nacional de Salta. Facultad de Ciencias de la Salud. Instituto de Patología Experimental; ArgentinaFil: Morea, Gastón. Universidad Nacional de Cuyo; ArgentinaFil: Cuello Carrión, Fernando Darío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo; ArgentinaFil: Scodeller, Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo; Argentin

Leishmaniasis in the Argentine Republic: Temporal and geographical distribution from 2013 to 2017

ARTÍCULO PUBLICADO EN REVISTA EXTERNA. Objective: To assess the temporal and geographical distribution of confirmed cases of cutaneous, mucocutaneous and visceral leishmaniasis in the Argentine Republic from 2013 to 2017. Methods: A retrospective study was carried out using data collected from the Integrated Surveillance Bulletin database of the National System of Health Surveillance. Confirmed cases of cutaneous, mucocutaneous and visceral leishmaniasis up to the 52nd epidemiological week of each year was included. Results: In the 5 years period, 1 295 confirmed leishmaniasis cases were reported in the Argentine Republic. One thousand twenty-eight (1 028) cases corresponded to cutaneous leishmaniasis (87.10%), being the most common type of leishmaniasis. Mucocutaneous leishmaniasis was in the second place in the country with 115 cases reported, mostly in the Northwest and Northeast regions. A total of 52 individuals with visceral leishmaniasis were identified and Misiones Province was the most affected. Conclusions: It is important to analyze the temporal and geographical distribution of leishmaniasis in order to provide an adequate management and surveillance

Native plants from Argentina reported as effective against Leishmania spp.

Leishmaniasis represents a spectrum of diseases caused by infection with protozoan pathogens of the genus Leishmania. It is a major neglected tropical disease associated with high rates of disability and death, with extended endemic areas in the Americas. Despite current therapeutic approaches, current treatments for leishmaniasis are unsatisfactory due to high associated toxicity, cost, complex administration and the emergence of resistant strains. Because of this, efforts have greatly increased over the last decade to identify novel compounds with anti-leishmanial properties. Thus, one strategy in the search for new compounds is the screening of molecules purified from plant sources. The current work reviewed the available information about the Argentinean natural sources reported as effective against Leishmania spp; including: its relevant chemical compounds, efficiency and applied methodology. Reported studies need to be considered as precursors works to extend the search between the profuse native plants from Argentina.Fil: Lozano, Esteban Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Fisiología; ArgentinaFil: Hapon, María Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo. ; ArgentinaFil: Cargnelutti, D. E.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo. ; ArgentinaFil: Gamarra Luques, Carlos Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin

Enhancement of Th1 immune responses to recombinant influenza nucleoprotein by Ribi adjuvant

A broad coverage influenza vaccine against multiple viral strains based on the viral nucleoprotein (NP) is a goal pursued by many laboratories. If the goal is to formulate the vaccine with recombinant NP it is essential to count on adjuvants capable of inducing cellular immunity. This work have studied the effect of the monophosphoryl lipid A and trehalose dimycolate, known as the Ribi Adjuvant System (RAS), in the immune response induced in mice immunized with recombinant NP. The NP was formulated with RAS and used to immunize BALB/c mice. Immunizations with NP-RAS increased the humoral and cellular immune responses compared to unadjuvanted NP. The predominant antibody isotype was IgG2a, suggesting the development of a Th1 response. Analysis of the cytokines from mice immunized with NP-RAS showed a significant increase in the production of IFN-gamma and a decreased production of IL-10 and IL-4 compared to controls without RAS. These results are similar to those usually obtained using Freund´s adjuvant, known to induce Th1 and CTL responses when co-administered with purified proteins, and suggest that a similar approach may be possible to enhance the performance of a T-cell vaccine containing NP.Fil: Cargnelutti, Diego Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina;Fil: Sanchez, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina;Fil: Alvarez, Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología; Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología;Fil: Boado, Lorena Analía. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología; Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología;Fil: Mattion, Nora Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología; Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología;Fil: Scodeller, Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina