title: A new Leishmania-specific hypothetical protein, LiHyT, used as a vaccine antigen against visceral leishmaniasis.
abstract: The present study aimed to evaluate a new Leishmania-specific hypothetical protein, LiHyT, as a vaccine candidate against VL. The immunogenicity of the recombinant protein (rLiHyT) plus saponin was evaluated in BALB/c mice. In the results, it is shown that rLiHyT plus saponin vaccinated mice produced high levels of IFN-γ, IL-12, and GM-CSF after in vitro stimulation of spleen cells using both rLiHyT and Leishmania infantum SLA. The protective efficacy was evaluated after subcutaneous challenge with stationary promastigotes of L. infantum. Immunized and infected mice, when compared to the controls, showed significant reductions in the number of parasites in the liver, spleen, bone marrow, and in the paws' draining lymph nodes. Protection was associated with an IL-12-dependent production of IFN-γ, mainly by CD4(+) T cells, with a minor contribution of CD8(+) T cells. In these mice, a decrease in the parasite-mediated IL-4 and IL-10 responses, as well as a predominance of LiHyT- and parasite-specific IgG2a isotype antibodies, were also observed. The present study showed that a new Leishmania-specific protein, when combined with a Th1-type adjuvant, presents potential to be used as a vaccine against VL.
authors.affiliation: Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Vívian Tamietti
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.
authors.forename: Daniela Pagliara
authors.initials: DP
authors.lastname: Lage
authors.affiliation: Departamento de Patologia Clínica, COLTEC, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Mariana Costa
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.
authors.forename: Lourena Emanuele
authors.initials: LE
authors.lastname: Costa
authors.affiliation: Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Departamento de Biología Molecular, Universidad Autónoma de Madrid, Madrid, Spain.
authors.forename: Esther
authors.initials: E
authors.lastname: Garde
authors.affiliation: Departamento de Patologia Clínica, COLTEC, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Marcella Rezende
authors.initials: MR
authors.lastname: Rodrigues
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.
authors.forename: Miguel Angel
authors.initials: MA
authors.lastname: Chávez-Fumagalli
authors.affiliation: Departamento de Patologia Clínica, COLTEC, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Daniel
authors.initials: D
authors.lastname: Menezes-Souza
authors.affiliation: Departamento de Patologia Clínica, COLTEC, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Bruno Mendes
authors.initials: BM
authors.lastname: Roatt
authors.affiliation: Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Carlos Alberto Pereira
authors.initials: CA
authors.lastname: Tavares
authors.affiliation: Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Departamento de Biología Molecular, Universidad Autónoma de Madrid, Madrid, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Soto
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. Electronic address: eduardoferrazcoelho@yahoo.com.br.
authors.forename: Eduardo Antonio Ferraz
authors.initials: EA
authors.lastname: Coelho
mesh_terms: D000818:Animals; D000953:Antigens, Protozoan / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D005260:Female; D007074:Immunoglobulin G / Q000097:blood; D015847:Interleukin-4 / Q000096:biosynthesis; D018314:Leishmania infantum / Q000276:immunology*; D007898:Leishmaniasis, Visceral / Q000517:prevention & control*; D051379:Mice; D008807:Mice, Inbred BALB C; D016052:Protozoan Vaccines / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology; D012503:Saponins / Q000276:immunology
chemical_list: D000953:Antigens, Protozoan; D007074:Immunoglobulin G; D016052:Protozoan Vaccines; D011994:Recombinant Proteins; D012503:Saponins; D015847:Interleukin-4
keywords: Hypothetical proteins; Immune adjuvants; Immunoproteomic approach; Leishmania infantum; Th1 immune response; Vaccine