Testing the Efficacy of a Multi-Component DNA-Prime/DNA-Boost Vaccine against Trypanosoma cruzi Infection in Dogs

Immunization of dogs with DNA-prime/DNA-boost vaccine (TcVac1) enhanced the Trypanosoma cruzi-specific type 1 antibody and CD8+ T cell responses that resulted in an early control of acute parasitemia and a moderate decline in pathological symptoms during chronic phase. Further improvement of vaccine-induced immunity would be required to achieve clinical and epidemiological benefits and prevent transmission of parasites from vaccinated/infected dogs to triatomines

Fluorescence Proteomic Technology to Analyze Peripheral Blood Mononuclear Cells in Chronic Chagas Disease

The thiol moieties of cysteinyl residues in proteins undergo a number of modifications including nitrosylation, oxidation, persulfidation, sulfenylation, and others. These protein modifications may influence gain as well as loss of function in biological and disease conditions. Herein, we describe a quantitative approach that combines accurate, sensitive fluorescence modification of cysteinyl-S-nitrosyl (SNOFlo) groups that leaves electrophoretic mobility unaffected and offers the measurement of changes in S-nitrosylation (SNO) status relative to protein abundance. This approach has been useful in evaluating the global protein abundance and SNO profile of Chagas seropositive individuals that were categorized in clinically asymptomatic (C/A) and clinically symptomatic (C/S) subgroups and compared to normal healthy (N/H) controls. Through analyzing the proteome datasets with different bioinformatics and statistics tools, potential pathologic mechanisms in disease progression are identified. We also propose a panel of protein biomarkers that have a potential to identify the infected individuals at risk of developing clinical Chagas disease.Fil: Wiktorowicz, John E.. University of Texas Medical Branch; Estados UnidosFil: Zago, María Paola. 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: Garg, Nisha J.. University of Texas Medical Branch; Estados Unido

Blood leukocytes from benznidazole-treated indeterminate chagas disease patients display an overall type-1-modulated cytokine profile upon short-term in vitro stimulation with <it>trypanosoma cruzi</it> antigens

<p>Abstract</p> <p>Background</p> <p>Benznidazole (Bz)-chemotherapy is recommended to prevent Chagas disease progression, despite its limited efficacy during chronic disease. However, the host mechanisms underlying these benefits still remain to be elucidated.</p> <p>Methods</p> <p>In this study, we have used short-term whole blood cultures to describe the cytokine profile of Bz-treated Indeterminate Chagas disease patients-(INDt) as compared to untreated patients-(IND).</p> <p>Results</p> <p>Our findings showed that IND presented increased levels of IL-10⁺neutrophils, IL-12⁺ and IL-10⁺monocytes and IFN-γ⁺NK-cells. Moreover, IND showed slight increase of IL-4⁺CD4⁺T-cells and enhanced levels of IL-10⁺CD8⁺T-cells and B-cells. Additional analysis of cytokine Low and High producers also highlighted the presence of High cytokine producers within IND, including IL-10 from CD4+ T-cells and IFN-γ from CD8⁺ T-cells, as compared to NI. The Bz-treatment lead to an overall cytokine down-regulation in the innate and adaptive compartments, including low levels of IL-12⁺ and IL-10⁺neutrophils and monocytes, IFN-γ⁺NK-cells, IL-12⁺, TNF-α⁺, IFN-γ⁺ and IL-5⁺CD4⁺T-cells and IL-10⁺B-cells, along with basal levels of cytokine-expressing CD8⁺T-cells in INDt as compared to IND. The in vitro antigen stimulation shifted the cytokine profile toward a type 1-modulated profile, with increased levels of IL-12⁺ and IL-10⁺ monocytes, IFN-γ⁺ and IL-4⁺NK-cells along with TNF-α⁺ and IFN-γ⁺CD8⁺T-cells. Analysis of Low and High cytokine producers, upon in vitro antigen stimulation, further confirm these data.</p> <p>Conclusion</p> <p>Together, our findings showed that the Bz treatment of Indeterminate Chagas’ disease patients shifts the cytokine patterns of peripheral blood monocytes, NK-cells and CD8⁺ T-cells towards a long-lasting Type-1-modulated profile that could be important to the maintenance of a non-deleterious immunological microenvironment.</p