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The new generation of vaccines for Chagas disease, are focused to induce both humoral and cellular response to effectively control Trypanosoma cruzi parasites. The administration of vaccine formulations intranasally has the advantage over parenteral routes that can induce a specific response at mucosal and systemic levels. This study aimed to evaluate and compare the immunogenicity and prophylactic effectiveness of two Trans-sialidase (TS)-based mucosal vaccines against T. cruzi administered intranasally. Vaccines consisted of a recombinant fragment of TS expressed in Lactococcus lactis formulated in two different adjuvants. The first, was an immunostimulant particle (ISPA, an ISCOMATRIX-like adjuvant), while the second was the dinucleotide c-di-AMP, which have shown immunostimulant properties at the mucosal level. BALB/c mice were immunized intranasally (3 doses, one every two weeks) with each formulation (TS + ISPA or TS + c-di-AMP) and with TS alone or vehicle (saline solution) as controls. Fifteen days after the last immunization, both TS + ISPA or TS + c-di-AMP induced an evident systemic humoral and cellular response, as judged by the increased plasma anti-TS IgG2a titers and IgG2a/IgG1 ratio and enhanced cellular response against TS. Plasma derived antibodies from TS + c-di-AMP also inhibit in vitro the invasion capacity of T. cruzi. Furthermore, specific secretory IgA was more enhanced in TS + c-di-AMP group. Protective efficacy was proved in vaccinated animals by an oral T. cruzi-challenge. Parasitemia control was only achieved by animals vaccinated with TS + c-di-AMP, despite all vaccinates groups showed enhanced CD8

La Enfermedad de Chagas (ECh), ocasionada por el parásito flagelado Trypanosoma cruzi (T. cruzi), es una de las parasitosis de mayor impacto en la Salud Pública de Latinoamérica. Si bien actualmente existen medidas de prevención como el tamizaje en bancos de sangre, el control a las embarazadas y el control vectorial, aún se requiere de estrategias más eficaces para evitar nuevos casos. Una de estas posibles estrategias es el desarrollo de una vacuna profiláctica contra T. cruzi. Desde el descubrimiento de la enfermedad en 1909, se han evaluado diferentes vacunas experimentales, pero aún no se ha logrado el desarrollo clínico de una formulación efectiva contra el parásito. En este artículo realizamos una revisión bibliográfica acerca de las distintas estrategias de vacunación que se evaluaron hasta la actualidad y, particularmente, el uso de la enzima Transialidasa (TS) como antígeno vacunal. También abordamos distintos aspectos de la superfamilia de la TS, como la clasificación de las distintas proteínas, sus características funcionales y su rol en la infección por T. cruzi. A lo largo de 100 años se han abordado y perfeccionado una gran diversidad de estrategias vacunales contra T. cruzi, lo cual permite augurar el salto desde el campo pre—clínico al desarrollo clínico de una vacuna efectiva en un futuro cercano.

Lipopolysaccharide (LPS) induces the activation of dendritic cells (DCs) throughout the engagement of toll-like receptor 4. LPS-activated DCs show increased capacity to process and present pathogen-derived antigens to activate naïve T cells. DCs-based vaccines have been successfully used to treat some cancer types, and lately transferred to the field of infectious diseases, in particular against HIV. However, there is no vaccine or DC therapy for any parasitic disease that is currently available. The immune response against