title: Phosphatidylserine exposure and surface sugars in two Leishmania (Viannia) braziliensis strains involved in cutaneous and mucocutaneous leishmaniasis.
abstract: BACKGROUND
  Phosphatidylserine (PS) and surface carbohydrates (SC) are known as virulence factors that may contribute to the different clinical symptoms ranging from self-healing cutaneous leishmaniasis lesions to fatal visceral disease. Leishmania (Viannia) braziliensis causes localized cutaneous leishmaniasis (LCL) and mucocutaneous leishmaniasis (MCL).
  
  
  METHODS
  We analyzed PS exposure and SC expression associated with 2 primary L. braziliensis isolates from patients with LCL or MCL. The role of PS exposure was also addressed during promastigotes phagocytosis by macrophages.
  
  
  RESULTS
  We observed higher PS exposure on the surface of late stationary growth phase promastigotes from patients with LCL, compared with those from patients with MCL, and both strains were alive during PS display. Reduction in the infectivity index was observed during macrophage interaction with late stationary growth phase promastigotes in which PS was blocked by annexin V. The major surface carbohydrates detected on LCL and MCL promastigotes were α-Man, α-Glc, and α-Gal. However, α-β-GalNAc, although observed on the surface of the LCL strain during the late stationary growth phase was highly expressed on the surface of early stationary growth phase promastigotes.
  
  
  CONCLUSIONS
  Our results suggest that PS and SC can modulate interactions between Leishmania organisms and host cells and may be important for the outcome of the clinical course of diseases caused by L. braziliensis.
authors.affiliation: Laboratório de Parasitologia e Laboratório de Biologia Estrutural, Universidade Federal do Pará, Belém, Pará, Brazil.
authors.forename: Luis Henrique S
authors.initials: LH
authors.lastname: Farias
authors.forename: Ana Paula D
authors.initials: AP
authors.lastname: Rodrigues
authors.forename: Fernando T
authors.initials: FT
authors.lastname: Silveira
authors.forename: Sérgio H
authors.initials: SH
authors.lastname: Seabra
authors.forename: Renato A
authors.initials: RA
authors.lastname: DaMatta
authors.forename: Elvira M
authors.initials: EM
authors.lastname: Saraiva
authors.forename: Edilene O
authors.initials: EO
authors.lastname: Silva
mesh_terms: D000372:Agglutination Tests; D000818:Animals; D050260:Carbohydrate Metabolism; D054884:Host-Pathogen Interactions; D007892:Leishmania braziliensis / Q000254:growth & development / Q000378:metabolism*; D016773:Leishmaniasis, Cutaneous / Q000276:immunology / Q000378:metabolism*; D007897:Leishmaniasis, Mucocutaneous / Q000276:immunology / Q000378:metabolism*; D008264:Macrophages / Q000276:immunology / Q000469:parasitology; D051379:Mice; D010718:Phosphatidylserines / Q000378:metabolism*
chemical_list: D010718:Phosphatidylserines