Pre-clinical antigenicity studies of an innovative multivalent vaccine for human visceral leishmaniasis

The notion that previous infection by Leishmania spp. in endemic areas leads to robust anti-Leishmania immunity, supports vaccination as a potentially effective approach to prevent disease development. Nevertheless, to date there is no vaccine available for human leishmaniasis. We optimized and asse...

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Detalles Bibliográficos
Autores: Cecílio, Pedro, Pérez-Cabezas, Begoña, Fernández, Laura, Moreno, Javier, Carrillo, Eugenia, Requena, Jose M, Fichera, Epifanio, Reed, Steven G, Coler, Rhea N, Kamhawi, Shaden, Oliveira, Fabiano, Valenzuela, Jesus G, Gradoni, Luigi, Glueck, Reinhard, Gupta, Gaurav, Cordeiro-da-Silva, Anabela
Tipo de recurso: artículo
Fecha de publicación:2017
País:España
Institución:Instituto de Salud Carlos III (ISCIII)
Repositorio:Repisalud
Idioma:inglés
OAI Identifier:oai:repisalud.isciii.es:20.500.12105/6890
Acceso en línea:http://hdl.handle.net/20.500.12105/6890
Access Level:acceso abierto
Palabra clave:Adjuvants, Immunologic
Animals
Antibodies, Protozoan
Antigens, Protozoan
Humans
Immunity, Cellular
Immunity, Humoral
Leishmania donovani
Leishmaniasis Vaccines
Leishmaniasis, Visceral
Lymphocyte Activation
Male
Mice
Mice, Inbred BALB C
Psychodidae
Recombinant Proteins
Saliva
Immunogenicity, Vaccine
Descripción
Sumario:The notion that previous infection by Leishmania spp. in endemic areas leads to robust anti-Leishmania immunity, supports vaccination as a potentially effective approach to prevent disease development. Nevertheless, to date there is no vaccine available for human leishmaniasis. We optimized and assessed in vivo the safety and immunogenicity of an innovative vaccine candidate against human visceral leishmaniasis (VL), consisting of Virus-Like Particles (VLP) loaded with three different recombinant proteins (LJL143 from Lutzomyia longipalpis saliva as the vector-derived (VD) component, and KMP11 and LeishF3+, as parasite-derived (PD) antigens) and adjuvanted with GLA-SE, a TLR4 agonist. No apparent adverse reactions were observed during the experimental time-frame, which together with the normal hematological parameters detected seems to point to the safety of the formulation. Furthermore, measurements of antigen-specific cellular and humoral responses, generally higher in immunized versus control groups, confirmed the immunogenicity of the vaccine formulation. Interestingly, the immune responses against the VD protein were reproducibly more robust than those elicited against leishmanial antigens, and were apparently not caused by immunodominance of the VD antigen. Remarkably, priming with the VD protein alone and boosting with the complete vaccine candidate contributed towards an increase of the immune responses to the PD antigens, assessed in the form of increased ex vivo CD4+ and CD8+ T cell proliferation against both the PD antigens and total Leishmania antigen (TLA). Overall, our immunogenicity data indicate that this innovative vaccine formulation represents a promising anti-Leishmania vaccine whose efficacy deserves to be tested in the context of the "natural infection".