title: New insights about cross-reactive epitopes of six trypanosomatid genera revealed that Crithidia and Leptomonas have antigenic similarity to L. (L.) chagasi.
abstract: We investigated whether ELISA using crude antigens from insect and plant trypanosomatids, which are non-pathogenic and easily cultivated in large scale, has the same positivity data as Leishmania (Leishmania) chagasi, the etiological agent of human visceral leishmaniasis (VL) or canine leishmaniasis (CanL), or as Trypanosoma cruzi, the etiological agent of Chagas disease (CD). The antigens from Crithidia fasciculata, Crithidia luciliae, and Leptomonas seymouri showed 100% cross-reactivity with VL and CanL samples, with no statistically titers differences from L. (L.) chagasi, however, 34% (17/50) of VL samples revealed higher titers using the insect trypanosomatids than the homologous antigen. On the other hand, antigens from Strigomonas culicis, Angomonas deanei, and Phytomonas serpens showed low cross-reactivity with VL and CanL samples. The sera from patients with American tegumentary leishmaniasis showed low levels of cross-reactivity with all trypanosomatids investigated, even with L. (L) chagasi, without titers dissimilarity among them. These parasites were also worthless as antigen source for detection of CD cases, which required homologous antigens to reach 100% positivity. This study showed, by ELISA, that crude extract of Crithidia and Leptomonas have epitopes similar to L. (L.) chagasi, which supports the idea of using them as antigens source for the serodiagnosis of visceral leishmaniasis.
authors.affiliation: Instituto de Medicina Tropical de São Paulo da Universidade de São Paulo (USP), São Paulo, SP, Brazil.
authors.forename: Leandro Rodrigues
authors.initials: LR
authors.lastname: Ferreira
authors.affiliation: Instituto de Medicina Tropical de São Paulo da Universidade de São Paulo (USP), São Paulo, SP, Brazil.
authors.forename: Norival
authors.initials: N
authors.lastname: Kesper
authors.affiliation: Departamento de Parasitologia do Instituto de Ciências Biomédicas-USP, São Paulo, SP, Brazil.
authors.forename: Marta M G
authors.initials: MM
authors.lastname: Teixeira
authors.affiliation: Departamento de Patologia da Faculdade de Medicina-USP, São Paulo, SP, Brazil.
authors.forename: Marcia Dalastra
authors.initials: MD
authors.lastname: Laurenti
authors.affiliation: Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: C L
authors.initials: CL
authors.lastname: Barbieri
authors.affiliation: Instituto de Infectologia Emílio Ribas de São Paulo, São Paulo, SP, Brazil.
authors.forename: José Angelo
authors.initials: JA
authors.lastname: Lindoso
authors.affiliation: Instituto de Medicina Tropical de São Paulo da Universidade de São Paulo (USP), São Paulo, SP, Brazil; Departamento de Medicina Preventiva da Faculdade de Medicina- USP, São Paulo, SP, Brazil. Electronic address: eumezawa@usp.br.
authors.forename: Eufrosina S
authors.initials: ES
authors.lastname: Umezawa
mesh_terms: D000818:Animals; D000953:Antigens, Protozoan / Q000737:chemistry / Q000276:immunology*; D014355:Chagas Disease / Q000276:immunology / Q000469:parasitology; D003421:Crithidia / Q000737:chemistry / Q000276:immunology*; D003429:Cross Reactions; D004285:Dogs; D000939:Epitopes / Q000737:chemistry / Q000276:immunology*; D006801:Humans; D007106:Immune Sera / Q000737:chemistry; D007893:Leishmania donovani / Q000737:chemistry / Q000276:immunology; D007894:Leishmania mexicana / Q000737:chemistry / Q000276:immunology; D016773:Leishmaniasis, Cutaneous / Q000276:immunology / Q000469:parasitology; D007898:Leishmaniasis, Visceral / Q000175:diagnosis* / Q000276:immunology / Q000469:parasitology; D008297:Male; D014349:Trypanosoma cruzi / Q000737:chemistry / Q000276:immunology*; D014351:Trypanosomatina / Q000737:chemistry / Q000276:immunology*
chemical_list: D000953:Antigens, Protozoan; D000939:Epitopes; D007106:Immune Sera
keywords: Crithidia; Cross-reactivity; L. (L.) chagasi; Leptomonas; Trypanosoma cruzi; Trypanosomatids