title: Use of a recombinant cysteine proteinase from Leishmania (Leishmania) infantum chagasi for the Immunotherapy of canine visceral Leishmaniasis.
abstract: BACKGROUND
  A recombinant cysteine proteinase from Leishmania (Leishmania) infantum chagasi (rLdccys1) was previously shown to induce protective immune responses against murine and canine visceral leishmaniasis. These findings encouraged us to use rLdccys1 in the immunotherapy of naturally infected dogs from Teresina, Piauí, a region of high incidence of visceral leishmaniasis in Brazil.
  
  
  RESULTS
  Thirty naturally infected mongrel dogs displaying clinical signs of visceral leishmaniasis were randomly divided in three groups: one group received three doses of rLdccys1 in combination with the adjuvant Propionibacterium acnes at one month interval between each dose; a second group received three doses of P. acnes alone; a third group received saline. The main findings were: 1) dogs that received rLdccys1 with P. acnes did not display increase of the following clinical signs: weight loss, alopecia, onychogryphosis, cachexia, anorexia, apathy, skin lesions, hyperkeratosis, ocular secretion, and enlarged lymph nodes; they also exhibited a significant reduction in the spleen parasite load in comparison to the control dogs; 2) rLdccys1-treated dogs exhibited a significant delayed type cutaneous hypersensitivity elicited by the recombinant antigen, as well as high IgG2 serum titers and low IgG1 serum titers; sera from rLdccys1-treated dogs also contained high IFN-γ and low IL-10 concentrations; 3) control dogs exhibited all of the clinical signs of visceral leishmaniasis and had low serum IgG2 and IFN-γ levels and high concentrations of IgG1 and IL-10; 4) all of the dogs treated with rLdccys1 were alive 12 months after treatment, whereas dogs which received either saline or P. acnes alone died within 3 to 7 months.
  
  
  CONCLUSIONS
  These findings illustrate the potential use of rLdccys1 as an additional tool for the immunotherapy of canine visceral leishmaniasis and support further studies designed to improve the efficacy of this recombinant antigen for the treatment of this neglected disease.
authors.affiliation: Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, São Paulo, Brazil; Departamento de Parasitologia e Microbiologia, Centro de Ciências da Saúde, Universidade Federal do Piauí, Teresina, Piauí, Brazil.
authors.forename: Josie Haydée Lima
authors.initials: JH
authors.lastname: Ferreira
authors.affiliation: Centro de Ciências Agrárias, Universidade Federal do Piauí, Teresina, Piauí, Brazil.
authors.forename: Lucilene Dos Santos
authors.initials: Ldos S
authors.lastname: Silva
authors.affiliation: Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, São Paulo, Brazil.
authors.forename: Ieda Maria
authors.initials: IM
authors.lastname: Longo-Maugéri
authors.affiliation: Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, São Paulo, Brazil.
authors.forename: Simone
authors.initials: S
authors.lastname: Katz
authors.affiliation: Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, São Paulo, Brazil.
authors.forename: Clara Lúcia
authors.initials: CL
authors.lastname: Barbiéri
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D001938:Brazil; D057056:Cysteine Proteases / Q000235:genetics / Q000627:therapeutic use*; D016207:Cytokines / Q000097:blood; D004283:Dog Diseases / Q000473:pathology / Q000628:therapy*; D004285:Dogs; D007167:Immunotherapy / Q000379:methods*; D018314:Leishmania infantum / Q000201:enzymology*; D007898:Leishmaniasis, Visceral / Q000473:pathology / Q000628:therapy / Q000662:veterinary*; D008297:Male; D051379:Mice; D015800:Protozoan Proteins / Q000235:genetics / Q000627:therapeutic use*; D011994:Recombinant Proteins / Q000235:genetics / Q000627:therapeutic use; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D000913:Antibodies, Protozoan; D016207:Cytokines; D015800:Protozoan Proteins; D011994:Recombinant Proteins; D057056:Cysteine Proteases