title: Diagnosis of American visceral leishmaniasis in humans and dogs using the recombinant Leishmania donovani A2 antigen.
abstract: A2 proteins are expressed in the amastigote stage of Leishmania donovani and are composed predominantely by a conserved repetitive element. Here, we have investigated the presence of anti-A2 antibodies in a panel of American Visceral Leishmaniasis (VL) sera. Anti-A2 antibodies were detected by ELISA, using a recombinant A2 protein containing a tag of six histidine residues (A2-HIS), in 77% of patients sera with symptomatic VL and in 87% of sera from dogs that tested positive in Leishmania immunofluorescent-antibody test (IFAT) or in the parasitological evaluation. Anti-A2 antibodies were also detected in 14 out of 15 symptomatic and in 10 out of 13 asymptomatic dogs. In addition, among the asymptomatic/anti-A2 positive animals, 9 were also positive for the presence of parasites. No significant cross reactivity was observed with sera of animals with other common canine diseases. Our findings suggest that A2 protein is a potential tool for the diagnosis of VL in the New World, and will be particularly useful for diagnosis of dogs.
authors.affiliation: Department of Biochemistry and Immunology, Federal University of Minas Gerais, MG, Belo Horizonte, Brazil.
authors.forename: Fernando A A
authors.initials: FA
authors.lastname: Carvalho
authors.forename: Hugues
authors.initials: H
authors.lastname: Charest
authors.forename: Carlos Alberto P
authors.initials: CA
authors.lastname: Tavares
authors.forename: Greg
authors.initials: G
authors.lastname: Matlashewski
authors.forename: Eneida Paganini
authors.initials: EP
authors.lastname: Valente
authors.forename: Ana
authors.initials: A
authors.lastname: Rabello
authors.forename: Ricardo T
authors.initials: RT
authors.lastname: Gazzinelli
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Fernandes
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D000953:Antigens, Protozoan; D004283:Dog Diseases / Q000175:diagnosis* / Q000469:parasitology; D004285:Dogs; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007893:Leishmania donovani / Q000276:immunology*; D007898:Leishmaniasis, Visceral / Q000175:diagnosis* / Q000469:parasitology / Q000662:veterinary; D015800:Protozoan Proteins / Q000276:immunology; D011994:Recombinant Proteins / Q000276:immunology
chemical_list: C107645:A2 protein, Leishmania donovani; D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D015800:Protozoan Proteins; D011994:Recombinant Proteins