title: A Leishmania-specific hypothetical protein expressed in both promastigote and amastigote stages of Leishmania infantum employed for the serodiagnosis of, and as a vaccine candidate against, visceral leishmaniasis.
abstract: BACKGROUND
  LiHyV is an antigenic hypothetical protein present in both promastigote and amastigote stages of Leishmania infantum, which was recently identified by an immunoproteomic approach. A recombinant version of this protein (rLiHyV) was evaluated as a diagnostic marker for canine VL (CVL). In addition, the prophylactic efficacy of the rLiHyV protein, and two of its CD8(+) T cell epitopes, has been analyzed in a murine model of visceral leishmaniasis (VL).
  
  
  METHODS
  Initially, the rLiHyV protein was evaluated by an ELISA technique for the serodiagnosis of CVL. Secondly, vaccines composed of the recombinant protein and both chemically synthesized peptides, combined with saponin as an adjuvant; were administered subcutaneously into BALB/c mice. The cellular and humoral responses generated by vaccination were evaluated. In addition, the parasite burden and immune response were studied 10 weeks after L. infantum infection.
  
  
  RESULTS
  The rLiHyV protein was recognized by antibodies of VL dogs. No cross-reactivity was obtained with sera from dogs vaccinated with a Brazilian commercial vaccine, with sera from animals infected with Trypanosoma cruzi, Babesia canis and Ehrlichia canis, or those from non-infected animals living in an endemic area for leishmaniasis. After challenge with L. infantum, spleen cells of BALB/c mice vaccinated with rLiHyV/saponin stimulated with parasite antigens showed a higher production of IFN-γ, IL-12 and GM-CSF, than the same cells obtained from mice vaccinated with the individual peptides, or mice from control (inoculated with saline or saponin) groups. This Th1-type cellular response observed in rLiHyV/saponin vaccinated mice was accompanied by the induction of parasite-specific IgG2a isotype antibodies. Animals immunized with rLiHyV/saponin showed significant reductions in the parasite burden in the liver, spleen, bone marrow and in the lymph nodes draining the paws relative to control mice.
  
  
  CONCLUSIONS
  The present study showed for the first time that the L. infantum LiHyV protein could be considered as a vaccine candidate against L. infantum infection, as well as a diagnostic marker for CVL.
authors.affiliation: Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. viviantamietti@yahoo.com.br.
authors.forename: Vivian T
authors.initials: VT
authors.lastname: Martins
authors.affiliation: Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. marianacostaduarte1@gmail.com.|Departamento de Patologia Clínica, COLTEC, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. marianacostaduarte1@gmail.com.
authors.forename: Mariana C
authors.initials: MC
authors.lastname: Duarte
authors.affiliation: Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. miguel.fumagalli@pq.cnpq.br.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Chávez-Fumagalli
authors.affiliation: Departamento de Patologia Clínica, COLTEC, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. daniel.ufop@gmail.com.|Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. daniel.ufop@gmail.com.
authors.forename: Daniel
authors.initials: D
authors.lastname: Menezes-Souza
authors.affiliation: RW Bioprospection Ltda, Belo Horizonte, Minas Gerais, Brazil. cecilia_perilo@hotmail.com.
authors.forename: Cecília S P
authors.initials: CS
authors.lastname: Coelho
authors.affiliation: Departamento de Medicina Veterinária Preventiva, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. danifm1@yahoo.com.br.
authors.forename: Danielle F
authors.initials: DF
authors.lastname: de Magalhães-Soares
authors.affiliation: Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. apfernandes.ufmg@gmail.com.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Fernandes
authors.affiliation: Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Departamento de Biología Molecular, Universidad Autónoma de Madrid, Madrid, Spain. msoto@cbm.uam.es.
authors.forename: Manuel
authors.initials: M
authors.lastname: Soto
authors.affiliation: Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. capt@icb.ufmg.br.
authors.forename: Carlos A P
authors.initials: CA
authors.lastname: Tavares
authors.affiliation: Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. eduardoferrazcoelho@yahoo.com.br.|Departamento de Patologia Clínica, COLTEC, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. eduardoferrazcoelho@yahoo.com.br.|Laboratório de Biotecnologia Aplicada ao Estudo das Leishmanioses, Departamento de Patologia Clínica, COLTEC, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, 31.270-901, Belo Horizonte, Minas Gerais, Brazil. eduardoferrazcoelho@yahoo.com.br.
authors.forename: Eduardo A F
authors.initials: EA
authors.lastname: Coelho
mesh_terms: D000818:Animals; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D004283:Dog Diseases / Q000097:blood*; D004285:Dogs; D005260:Female; D018314:Leishmania infantum / Q000235:genetics / Q000302:isolation & purification*; D007898:Leishmaniasis, Visceral / Q000097:blood / Q000175:diagnosis / Q000517:prevention & control / Q000662:veterinary*; D051379:Mice; D008807:Mice, Inbred BALB C; D015800:Protozoan Proteins; D016052:Protozoan Vaccines / Q000276:immunology*; D012698:Serologic Tests / Q000662:veterinary*
chemical_list: D015800:Protozoan Proteins; D016052:Protozoan Vaccines; D004247:DNA