title: Proteomic analysis of the soluble proteomes of miltefosine-sensitive and -resistant Leishmania infantum chagasi isolates obtained from Brazilian patients with different treatment outcomes.
abstract: The mechanism of miltefosine-resistance in Leishmania spp. has been partially determined in experimental resistant lines; however, studies using clinical isolates with different miltefosine susceptibilities are still needed. In our study, we used a proteomic 2D-DIGE/MS approach to study different protein abundances in miltefosine-sensitive and -resistant Leishmania infantum chagasi isolates from visceral leishmaniasis patients with different miltefosine treatment outcomes. The high-resolution proteome obtained from these isolates showed 823 matched spots and 46 spots exhibited different abundances between the isolates. Out of these differentially expressed spots, 26 (56.5%) showed greater and 20 (43.5%) showed lower expression of the resistant isolate compared to the sensitive isolate. MALDI/TOF-TOF mass spectrometry allowed the identification of 32 spots with unique protein identification correspondent to 22 non-redundant proteins. Most of the proteins up-regulated in the proteome miltefosine-resistant isolates were associated with redox homeostasis, stress response, protection to apoptosis, and drug translocation. These differentially expressed proteins are likely involved in miltefosine natural resistance and suggest that the miltefosine-resistance mechanism in Leishmania is multifactorial.
  
  
  CONCLUSIONS
  Visceral leishmaniasis (VL) is a serious disease with a challenging treatment plan requiring the prolonged and painful applications of poorly tolerated toxic drugs. Therefore, the identification of miltefosine, an effective and safe oral drug, was considered a significant advancement in leishmaniasis therapy. However, different sensitivities to miltefosine in Leishmania have been observed in clinically relevant species, and the biological mechanism by which clinical isolates of Leishmania acquire drug resistance is poorly understood. Our work aims to elucidate the mechanism of natural resistance to miltefosine in Leishmania by studying the isolates from VL patients who displayed different miltefosine treatment outcomes.
authors.affiliation: Laboratório de Leishmanioses, Núcleo de Doenças Infecciosas, Universidade Federal do Espírito Santo, Vitória, ES, Brazil; Laboratório de Química de Proteínas, Departamento de Ciências Fisiológicas, Universidade Federal do Espírito Santo, Vitória, ES, Brazil.
authors.forename: Juliana B T
authors.initials: JB
authors.lastname: Carnielli
authors.affiliation: Laboratório de Leishmanioses, Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Hélida M
authors.initials: HM
authors.lastname: de Andrade
authors.affiliation: Laboratório de Leishmanioses, Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Simone F
authors.initials: SF
authors.lastname: Pires
authors.affiliation: Laboratório de Toxinologia, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, Brazil.
authors.forename: Alexander D
authors.initials: AD
authors.lastname: Chapeaurouge
authors.affiliation: Laboratório de Toxinologia, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, Brazil.
authors.forename: Jonas
authors.initials: J
authors.lastname: Perales
authors.affiliation: Laboratório de Leishmanioses, Núcleo de Doenças Infecciosas, Universidade Federal do Espírito Santo, Vitória, ES, Brazil.
authors.forename: Renata
authors.initials: R
authors.lastname: Monti-Rocha
authors.affiliation: Hospital Universitário Clemente de Faria, Universidade Estadual de Montes Claros, Montes Claros, MG, Brazil.
authors.forename: Sílvio F G
authors.initials: SF
authors.lastname: Carvalho
authors.affiliation: Laboratório de Química de Proteínas, Departamento de Ciências Fisiológicas, Universidade Federal do Espírito Santo, Vitória, ES, Brazil.
authors.forename: Leonardo P
authors.initials: LP
authors.lastname: Ribeiro
authors.affiliation: Laboratório de Leishmanioses, Núcleo de Doenças Infecciosas, Universidade Federal do Espírito Santo, Vitória, ES, Brazil.
authors.forename: Reynaldo
authors.initials: R
authors.lastname: Dietze
authors.affiliation: Laboratório de Química de Proteínas, Departamento de Ciências Fisiológicas, Universidade Federal do Espírito Santo, Vitória, ES, Brazil.
authors.forename: Suely G
authors.initials: SG
authors.lastname: Figueiredo
authors.affiliation: Laboratório de Leishmanioses, Núcleo de Doenças Infecciosas, Universidade Federal do Espírito Santo, Vitória, ES, Brazil. Electronic address: lemosem@ndi.ufes.br.
authors.forename: Elenice M
authors.initials: EM
authors.lastname: Lemos
mesh_terms: D000981:Antiprotozoal Agents / Q000008:administration & dosage*; D001938:Brazil; D004351:Drug Resistance / Q000187:drug effects / Q000235:genetics; D005260:Female; D006801:Humans; D018314:Leishmania infantum / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D007898:Leishmaniasis, Visceral / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism; D008297:Male; D010767:Phosphorylcholine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D000981:Antiprotozoal Agents; D015800:Protozoan Proteins; D010767:Phosphorylcholine; C039128:miltefosine
keywords: 2D-DIGE; L. infantum chagasi; MS/MS; Miltefosine resistance; Proteome