| Autor: |
Bello J; Laboratory of Molecular Immunology,Department of Microbiology,Faculty of Biological Sciences,Universidad de Concepción,Concepción,Chile., Sáez D; Laboratory of Molecular Immunology,Department of Microbiology,Faculty of Biological Sciences,Universidad de Concepción,Concepción,Chile., Escalona E; Laboratory of Molecular Immunology,Department of Microbiology,Faculty of Biological Sciences,Universidad de Concepción,Concepción,Chile., Velozo P; Microbiology Laboratory,Department of Biochemistry and Molecular Biology,School of Chemical and Pharmaceutical Sciences,Universidad de Chile,Santiago,Chile., Santiviago CA; Microbiology Laboratory,Department of Biochemistry and Molecular Biology,School of Chemical and Pharmaceutical Sciences,Universidad de Chile,Santiago,Chile., Contreras I; Microbiology Laboratory,Department of Biochemistry and Molecular Biology,School of Chemical and Pharmaceutical Sciences,Universidad de Chile,Santiago,Chile., Oñate Á; Laboratory of Molecular Immunology,Department of Microbiology,Faculty of Biological Sciences,Universidad de Concepción,Concepción,Chile. |
| Abstrakt: |
Salmonella Enteritidis is the main cause of foodborne salmonellosis worldwide. The limited effectiveness of current interventions against this pathogen has been the main incentive to develop new methods for the efficient control of this infection. To investigate the use of DNA vaccines against S. Enteritidis in humans, immune responses stimulated by two plasmids containing the genes designated SEN1002, located in the pathogenicity island SPI-19 and encoding a Hcp protein involved in transport mechanisms, and SEN1395, located in the genomic island ΦSE14 and encoding a protein of a new superfamily of lysozymes, were evaluated. Humoral and cellular responses following intranasal immunization of two groups of BALB/c mice with the plasmids pV1002 and pV1395 plus adjuvant were evaluated and it was observed that the IgG2a/IgG1 ratios were sixfold higher than control groups. Both plasmids stimulated specific secretory IgA production. Increased proliferation of lymphocytes and IFN-γ production were detected in both experimental groups. DNA-vaccinated mice developed protective immunity against a virulent strain of S. Enteritidis, with nearly 2 logs of protection level compared to the negative control values in the spleen. Therefore, DNA vaccines are efficient at stimulating cellular and humoral immune responses at systemic and mucosal levels. |
