title: Functional transcriptomics of wild-caught Lutzomyia intermedia salivary glands: identification of a protective salivary protein against Leishmania braziliensis infection.
abstract: BACKGROUND
  Leishmania parasites are transmitted in the presence of sand fly saliva. Together with the parasite, the sand fly injects salivary components that change the environment at the feeding site. Mice immunized with Phlebotomus papatasi salivary gland (SG) homogenate are protected against Leishmania major infection, while immunity to Lutzomyia intermedia SG homogenate exacerbated experimental Leishmania braziliensis infection. In humans, antibodies to Lu. intermedia saliva are associated with risk of acquiring L. braziliensis infection. Despite these important findings, there is no information regarding the repertoire of Lu. intermedia salivary proteins.
  
  
  RESULTS
  A cDNA library from the Salivary Glands (SGs) of wild-caught Lu. intermedia was constructed, sequenced, and complemented by a proteomic approach based on 1D SDS PAGE and mass/mass spectrometry to validate the transcripts present in this cDNA library. We identified the most abundant transcripts and proteins reported in other sand fly species as well as novel proteins such as neurotoxin-like proteins, peptides with ML domain, and three small peptides found so far only in this sand fly species. DNA plasmids coding for ten selected transcripts were constructed and used to immunize BALB/c mice to study their immunogenicity. Plasmid Linb-11--coding for a 4.5-kDa protein--induced a cellular immune response and conferred protection against L. braziliensis infection. This protection correlated with a decreased parasite load and an increased frequency of IFN-γ-producing cells.
  
  
  CONCLUSIONS
  We identified the most abundant and novel proteins present in the SGs of Lu. intermedia, a vector of cutaneous leishmaniasis in the Americas. We also show for the first time that immunity to a single salivary protein from Lu. intermedia can protect against cutaneous leishmaniasis caused by L. braziliensis.
authors.affiliation: Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz (FIOCRUZ), Salvador, Bahia, Brazil.
authors.forename: Tatiana R
authors.initials: TR
authors.lastname: de Moura
authors.forename: Fabiano
authors.initials: F
authors.lastname: Oliveira
authors.forename: Marcia W
authors.initials: MW
authors.lastname: Carneiro
authors.forename: José Carlos
authors.initials: JC
authors.lastname: Miranda
authors.forename: Jorge
authors.initials: J
authors.lastname: Clarêncio
authors.forename: Manoel
authors.initials: M
authors.lastname: Barral-Netto
authors.forename: Cláudia
authors.initials: C
authors.lastname: Brodskyn
authors.forename: Aldina
authors.initials: A
authors.lastname: Barral
authors.forename: José M C
authors.initials: JM
authors.lastname: Ribeiro
authors.forename: Jesus G
authors.initials: JG
authors.lastname: Valenzuela
authors.forename: Camila I
authors.initials: CI
authors.lastname: de Oliveira
mesh_terms: D000569:Americas; D000818:Animals; D004195:Disease Models, Animal; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D020869:Gene Expression Profiling; D015723:Gene Library; D006801:Humans; D007111:Immunity, Cellular; D019476:Insect Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D007892:Leishmania braziliensis / Q000276:immunology*; D016773:Leishmaniasis, Cutaneous / Q000276:immunology / Q000517:prevention & control; D013058:Mass Spectrometry; D051379:Mice; D008807:Mice, Inbred BALB C; D020543:Proteome / Q000032:analysis; D011576:Psychodidae / Q000235:genetics* / Q000276:immunology / Q000469:parasitology; D012471:Salivary Proteins and Peptides / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification
chemical_list: D019476:Insect Proteins; D020543:Proteome; D012471:Salivary Proteins and Peptides