RESUMEN
Yellow fever (YF) is a disease caused by the homonymous flavivirus that can be prevented by a vaccine containing attenuated viruses. Since some individuals cannot receive this vaccine, the development of alternatives is desirable. Here, we developed a recombinant baculovirus (rBV) surface display platform utilizing a chimeric E-NS1 protein as a vaccine candidate. A pBacPAK9 vector containing the baculoviral GP64 signal peptide, the YFV prM, E, NS1 and the ectodomain of VSV-G sequences was synthesized. This transfer plasmid and the bAcGOZA bacmid were cotransfected into Sf9 cells, and an rBV-E-NS1 was obtained, which was characterized by PCR, WB, IFI and FACS analysis. Mice immunized with rBV-E-NS1 elicited a specific humoral and cellular immune response and were protected after YFV infection. In summary, we have developed an rBV that expresses YFV major antigen proteins on its surface, which opens new alternatives that can be tested in a mouse model.
RESUMEN
The New World (NW) mammarenavirus Junín (JUNV) is the etiological agent of Argentine hemorrhagic fever, a human endemic disease of Argentina. Promyelocytic leukemia protein (PML) has been reported as a restriction factor for several viruses although the mechanism/s behind PML-mediated antiviral effect may be diverse and are a matter of debate. Previous studies have reported a nuclear to cytoplasm translocation of PML during the murine Old World mammarenavirus lymphocytic choriomeningitis virus (LCMV) infection. This translocation was found to be mediated by the viral Z protein. Here, we show that PML restricts JUNV infection in human A549 cells. However, in contrast to LCVM, JUNV infection enhances PML expression and PML is not translocated to the cytoplasm neither it colocalizes with JUNV Z protein. Our study demonstrates that a NW mammarenavirus as JUNV interacts differently with the antiviral protein PML than LCMV.
Asunto(s)
Fiebre Hemorrágica Americana , Virus Junin , Proteína de la Leucemia Promielocítica , Células A549 , Fiebre Hemorrágica Americana/metabolismo , Humanos , Proteína de la Leucemia Promielocítica/genética , Proteínas Virales , Replicación ViralRESUMEN
The New World arenavirus Junin (JUNV) is the etiological agent of Argentine hemorrhagic fever (AHF). Previous studies of human macrophage infection by the Old-World arenaviruses Mopeia and Lassa showed that while the non-pathogenic Mopeia virus replicates and activates human macrophages, the pathogenic Lassa virus replicates but fails to activate human macrophages. Less is known in regard to the impact of New World arenavirus infection on the human macrophage immune response. Macrophage activation is critical for controlling infections but could also be usurped favoring immune evasion. Therefore, it is crucial to understand how the JUNV infection modulates macrophage plasticity to clarify its role in AHF pathogenesis. With this aim in mind, we compared infection with the attenuated Candid 1 (C#1) or the pathogenic P strains of the JUNV virus in human macrophage cultures. The results showed that both JUNV strains similarly replicated and induced morphological changes as early as 1 day post-infection. However, both strains differentially induced the expression of CD71, the receptor for cell entry, the activation and maturation molecules CD80, CD86, and HLA-DR and selectively modulated cytokine production. Higher levels of TNF-α, IL-10, and IL-12 were detected with C#1 strain, while the P strain induced only higher levels of IL-6. We also found that C#1 strain infection skewed macrophage polarization to M1, whereas the P strain shifted the response to an M2 phenotype. Interestingly, the MERTK receptor, that negatively regulates the immune response, was down-regulated by C#1 strain and up-regulated by P strain infection. Similarly, the target genes of MERTK activation, the cytokine suppressors SOCS1 and SOCS3, were also increased after P strain infection, in addition to IRF-1, that regulates type I IFN levels, which were higher with C#1 compared with P strain infection. Together, this differential activation/polarization pattern of macrophages elicited by P strain suggests a more evasive immune response and may have important implications in the pathogenesis of AHF and underpinning the development of new potential therapeutic strategies.
Asunto(s)
Fiebre Hemorrágica Americana/inmunología , Virus Junin/inmunología , Activación de Macrófagos , Macrófagos/inmunología , Animales , Antígeno B7-1/inmunología , Antígeno B7-2/inmunología , Chlorocebus aethiops , Cricetinae , Citocinas/inmunología , Antígenos HLA-DR/inmunología , Fiebre Hemorrágica Americana/patología , Humanos , Especificidad de la Especie , Células VeroRESUMEN
A series of new 2-aminonaphthoquinones and related compounds were synthesized and evaluated in vitro as trypanocidal and cytotoxic agents. Some tested compounds inhibited epimastigote growth and trypomastigote viability. Several compounds showed similar or higher activity and selectivity as compared with current trypanocidal drug, nifurtimox. Compound 4l exhibit higher selectivity than nifurtimox against Trypanosoma cruzi in comparison with Vero cells. Some of the synthesized quinones were tested against cancer cells and normal fibroblasts, showing that certain chemical modifications on the naphthoquinone moiety induce and excellent increase the selectivity index of the cytotoxicity (4g and 10). The results presented here show that the anti-T. cruzi activity of 2-aminonaphthoquinones derivatives can be improved by the replacement of the benzene ring by a pyridine moiety. Interestingly, the presence of a chlorine atom at C-3 and a highly lipophilic alkyl group or aromatic ring are newly observed elements that should lead to the discovery of more selective cytotoxic and trypanocidal compounds.
Asunto(s)
Compuestos de Anilina/farmacología , Fibroblastos/efectos de los fármacos , Naftoquinonas/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Compuestos de Anilina/síntesis química , Compuestos de Anilina/química , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Chlorocebus aethiops , Relación Dosis-Respuesta a Droga , Humanos , Células MCF-7 , Estructura Molecular , Naftoquinonas/síntesis química , Naftoquinonas/química , Pruebas de Sensibilidad Parasitaria , Relación Estructura-Actividad , Tripanocidas/síntesis química , Tripanocidas/química , Tripanocidas/toxicidad , Células VeroRESUMEN
Trypanosoma cruzi glutamate cysteine ligase (TcGCL) is considered a potential drug target to develop novel antichagasic drugs. We have used a variety of computational methods to investigate the interactions between TcGCL with Glutathione (GSH). The three-dimensional structure of TcGCL was constructed by comparative modeling methods using the Saccharomyces cerevisiae glutamate cysteine ligase as template. Molecular dynamics simulations were used to validate the TcGCL model and to analyze the molecular interactions with GSH. Using RMSD clustering, the most prevalent GSH binding modes were identified paying attention to the residues involved in the molecular interactions. The GSH binding modes were used to propose pharmacophore models that can be exploited in further studies to identify novel antichagasic compounds.
Asunto(s)
Glutamato-Cisteína Ligasa/química , Glutatión/química , Proteínas Protozoarias/química , Proteínas de Saccharomyces cerevisiae/química , Trypanosoma cruzi/química , Secuencia de Aminoácidos , Sitios de Unión , Diseño de Fármacos , Cinética , Simulación de Dinámica Molecular , Datos de Secuencia Molecular , Unión Proteica , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/enzimología , Homología Estructural de Proteína , Termodinámica , Tripanocidas/química , Trypanosoma cruzi/enzimologíaRESUMEN
Fundada em 1971 pelo médico homeopata Dr. Tomás Pablo Paschero, a escola oferece cursos de homeopatia para médicos homeopatas, veterinários e farmacêuticos. Possui curso de pós-graduação em homeopatia, realiza congressos internacionais, palestras e complementa suas atividades academicas em consultórios externos.