title: Immunogenicity in dogs and protection against visceral leishmaniasis induced by a 14kDaLeishmania infantumrecombinant polypeptide.
abstract: In areas were human visceral leishmaniasis (VL) is endemic, the domestic dog is the main parasite reservoir in the infectious cycle ofLeishmania infantum. Development of prophylactic strategies to lower the parasite burden in dogs would reduce sand fly transmission thus lowering the incidence of zoonotic VL. Here we demonstrate that vaccination of dogs with a recombinant 14kDa polypeptide ofL. infantumnuclear transport factor 2 (Li-ntf2) mixed with adjuvantBpMPLA-SE resulted in the production of specific anti-Li-ntf2IgG antibodies as well as IFN-γ release by the animals' peripheral blood mononuclear cells stimulated with the antigen. In addition, immunization with this single and small 14kDa poplypeptide resulted in protracted progression of the infection of the animals after challenging with a high dose of virulentL. infantum. Five months after challenge the parasite load was lower in the bone marrow of immunized dogs compared to non-immunized animals. The antibody response to K39, a marker of active VL, at ten months after challenge was strong and significantly higher in the control dogs than in vaccinated animals. At the study termination vaccinated animals showed significantly more liver granulomas and lymphoid hyperplasia than non-vaccinated animals, which are both histological markers of resistance to infection. Together, these results indicate that the 14kDa polypeptide is an attractive protective molecule that can be easily incorporated in a leishmanial polyprotein vaccine candidate to augment/complement the overall protective efficacy of the final product.
authors.affiliation: DetectoGen Inc. Grafton MA.
authors.forename: Claudia
authors.initials: C
authors.lastname: Abeijon
authors.affiliation: The Forsyth Institute, Cambridge MA.
authors.forename: Nada
authors.initials: N
authors.lastname: Daifalla
authors.affiliation: Cummings School of Veterinary Medicine at Tufts, Grafton MA.
authors.forename: Greice
authors.initials: G
authors.lastname: Krautz-Peterson
authors.affiliation: Cummings School of Veterinary Medicine at Tufts, Grafton MA.
authors.forename: Stefano
authors.initials: S
authors.lastname: Pizzirani
authors.affiliation: Cummings School of Veterinary Medicine at Tufts, Grafton MA.
authors.forename: Gillian
authors.initials: G
authors.lastname: Beamer
authors.affiliation: BioIndustrial Division, Butantan Institute/Foundation, São Paulo, SP, Brazil.
authors.forename: Neuza M
authors.initials: NM
authors.lastname: Frazatti-Gallina
authors.affiliation: BioIndustrial Division, Butantan Institute/Foundation, São Paulo, SP, Brazil.
authors.forename: Isaias
authors.initials: I
authors.lastname: Raw
authors.affiliation: DetectoGen Inc. Grafton MA ; The Forsyth Institute, Cambridge MA.
authors.forename: Antonio
authors.initials: A
authors.lastname: Campos-Neto
keywords: Dog; L. infantum nuclear transport factor 2; Leishmania infantum; Vaccine; Visceral Leishmaniasis