title: Increased association of Trypanosoma cruzi with sialoadhesin positive mice macrophages.
abstract: Trypanosoma cruzi is a parasite with large amounts of sialic acid (SA) residues exposed at its surface that seems to be involved in macrophages infection. Some macrophages, present in T. cruzi infected tissues, expresses sialoadhesin (Sn), a receptor that recognizes SA. Thus, the involvement of Sn in the association of T. cruzi to macrophages was investigated. Sn was induced in mice peritoneal macrophages by homologous serum (HS) cultivation. Epimastigotes and trypomastigotes associated more to HS cultured macrophages than to fetal bovine serum (FBS). Blocking of Sn with antibodies reduced the association of trypomastigotes to similar level as for FBS cultured macrophages. Desialylation reduced the association of parasites to HS cultured macrophages indicating the Sn importance. Furthermore, the entrance mechanism of trypomastigotes to Sn positive macrophages has a phagocytic nature as demonstrated by scanning electron microscopy and cytochalasin D treatment. Sn positive macrophages may important in the initial trypomastigote infection, thus in the establishment of Chagas disease.
authors.affiliation: Laboratòrio de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, 28013-600 Parque Califórnia, Campos dos Goytacazes, RJ, Brazil.
authors.forename: Verônica G
authors.initials: VG
authors.lastname: Monteiro
authors.forename: Caroliny S S
authors.initials: CS
authors.lastname: Lobato
authors.forename: Alexandre R
authors.initials: AR
authors.lastname: Silva
authors.forename: Diego V
authors.initials: DV
authors.lastname: Medina
authors.forename: Marco A
authors.initials: MA
authors.lastname: de Oliveira
authors.forename: Sergio H
authors.initials: SH
authors.lastname: Seabra
authors.forename: Wanderley
authors.initials: W
authors.lastname: de Souza
authors.forename: Renato A
authors.initials: RA
authors.lastname: DaMatta
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D014355:Chagas Disease / Q000469:parasitology; D004912:Erythrocytes / Q000378:metabolism; D017737:Macrophages, Peritoneal / Q000378:metabolism / Q000469:parasitology*; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D008855:Microscopy, Electron, Scanning; D019158:N-Acetylneuraminic Acid / Q000378:metabolism; D011971:Receptors, Immunologic / Q000378:metabolism*; D063267:Sialic Acid Binding Ig-like Lectin 1; D014349:Trypanosoma cruzi / Q000254:growth & development / Q000472:pathogenicity*
chemical_list: D008562:Membrane Glycoproteins; D011971:Receptors, Immunologic; D063267:Sialic Acid Binding Ig-like Lectin 1; C571167:Siglec1 protein, mouse; D019158:N-Acetylneuraminic Acid