title: Intranasal vaccination with leishmanial antigens protects golden hamsters (Mesocricetus auratus) against Leishmania (Viannia) Braziliensis infection.
abstract: BACKGROUND
  Previous results have shown that oral and intranasal administration of particulate Leishmania (Leishmania) amazonensis antigens (LaAg) partially protects mice against L. amazonensis infection. However, vaccination studies on species of the subgenus Viannia, the main causative agent of cutaneous and mucosal leishmaniasis in the Americas, have been hampered by the lack of easy-to-handle bio-models that accurately mimic the human disease. Recently, we demonstrated that the golden hamster is an appropriate model for studying the immunopathogenesis of cutaneous leishmaniasis caused by L. (Viannia) braziliensis. Using the golden hamster model, our current study investigated whether the protective effect of intranasal immunisation with LaAg can be extended to L. braziliensis infection.
  
  
  RESULTS
  Golden hamsters vaccinated with either two intranasal (IN) doses of LaAg (10 µg) or two intramuscular doses of LaAg (20 µg) were challenged 2 weeks post-vaccination with L. braziliensis. The results showed that IN immunisation with LaAg significantly reduced lesion growth and parasitic load as well as serum IgG and IgG2 levels. At the experimental endpoint on day 114 post-infection, IN-immunised hamsters that were considered protected expressed IFN-γ and IL10 mRNA levels that returned to uninfected skin levels. In contrast to the nasal route, intramuscular (IM) immunisation failed to provide protection.
  
  
  CONCLUSIONS
  These results demonstrate for the first time that the nasal route of immunisation can induce cross protection against L. braziliensis infection.
authors.affiliation: Laboratório Interdisciplinar de Pesquisas Médicas - Instituto Oswaldo Cruz - FIOCRUZ, Rio de Janeiro, Brazil.
authors.forename: Luzinei
authors.initials: L
authors.lastname: da Silva-Couto
authors.affiliation: Laboratório Interdisciplinar de Pesquisas Médicas - Instituto Oswaldo Cruz - FIOCRUZ, Rio de Janeiro, Brazil.
authors.forename: Raquel Peralva
authors.initials: RP
authors.lastname: Ribeiro-Romão
authors.affiliation: Laboratório Interdisciplinar de Pesquisas Médicas - Instituto Oswaldo Cruz - FIOCRUZ, Rio de Janeiro, Brazil.
authors.forename: Andrea Franco
authors.initials: AF
authors.lastname: Saavedra
authors.affiliation: Laboratório de Imunofarmacologia - Instituto de Biofísica Carlos Chagas Filho, UFRJ, Rio de Janeiro, Brazil.
authors.forename: Beatriz Lilian
authors.initials: BL
authors.lastname: da Silva Costa Souza
authors.affiliation: Laboratório de Biologia Molecular e Doenças Endêmicas - Instituto Oswaldo Cruz - FIOCRUZ, Rio de Janeiro, Brazil.
authors.forename: Otacílio Cruz
authors.initials: OC
authors.lastname: Moreira
authors.affiliation: Laboratório Interdisciplinar de Pesquisas Médicas - Instituto Oswaldo Cruz - FIOCRUZ, Rio de Janeiro, Brazil.
authors.forename: Adriano
authors.initials: A
authors.lastname: Gomes-Silva
authors.affiliation: Laboratório de Imunofarmacologia - Instituto de Biofísica Carlos Chagas Filho, UFRJ, Rio de Janeiro, Brazil.
authors.forename: Bartira
authors.initials: B
authors.lastname: Rossi-Bergmann
authors.affiliation: Laboratório Interdisciplinar de Pesquisas Médicas - Instituto Oswaldo Cruz - FIOCRUZ, Rio de Janeiro, Brazil.
authors.forename: Alda Maria
authors.initials: AM
authors.lastname: Da-Cruz
authors.affiliation: Laboratório Interdisciplinar de Pesquisas Médicas - Instituto Oswaldo Cruz - FIOCRUZ, Rio de Janeiro, Brazil.
authors.forename: Eduardo Fonseca
authors.initials: EF
authors.lastname: Pinto
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan / Q000276:immunology*; D006224:Cricetinae; D007074:Immunoglobulin G / Q000097:blood; D007371:Interferon-gamma / Q000378:metabolism; D007892:Leishmania braziliensis / Q000276:immunology*; D054332:Leishmaniasis Vaccines / Q000008:administration & dosage / Q000276:immunology*; D016773:Leishmaniasis, Cutaneous / Q000517:prevention & control*; D059208:Parasite Load; D012867:Skin / Q000378:metabolism / Q000469:parasitology
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D007074:Immunoglobulin G; D054332:Leishmaniasis Vaccines; D007371:Interferon-gamma