title: Evaluation of three recombinant Leishmania infantum antigens in human and canine visceral leishmaniasis diagnosis.
abstract: Visceral leishmaniasis (VL) is a neglected disease and is fatal if untreated. Dogs serve as reservoirs for Leishmania infantum (syn. L. chagasi) due to their susceptibility to infection and high skin parasitism. Therefore, VL control in Brazil involves the elimination of seropositive dogs, among other actions. However, the most frequently used serological tests have limitations regarding sensitivity and specificity. In this study, we have selected three Leishmania antigens (C1, C8 and C9) and have produced them as recombinant proteins using pET-28a-TEV vector and Escherichia coli BL-21 as expression system. When tested in ELISA with human samples, the C9 antigen was the one showing the most promising results, with 68% sensitivity and 78% specificity. When testing canine samples, the C1, C8 and C9 antigens showed a sensitivity range from 70% to 80% and specificity range from 60% to 90%. The C1 antigen presented higher sensitivity (80%) and the C8 antigen presented higher specificity (90%). Due to it, we decided to mix and test C1 and C8 antigens together, resulting in the C18 antigen. The mix also yielded high percentages of detected symptomatic and asymptomatic dogs however it did not improve the performance of the diagnostic. Comparison of our tests with the tests recommended by the Brazilian Ministry of Health revealed that our antigens' sensitivities and the percentage of detected asymptomatic dogs were much higher. Our results suggest that the C1, C8, C18 and C9 recombinant proteins are good antigens to diagnose canine visceral leishmaniasis and could potentially be used in screening tests. To diagnose human visceral leishmaniasis, the C9 antigen presented reasonable results, but more optimization must be performed for this antigen to provide better performance.
authors.affiliation: Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Parasitologia, Avenida Antônio Carlos, 6627, Pampulha, CEP 31270-901 Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Aliani Moura
authors.initials: AM
authors.lastname: Fonseca
authors.affiliation: Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Parasitologia, Avenida Antônio Carlos, 6627, Pampulha, CEP 31270-901 Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Angélica Rosa
authors.initials: AR
authors.lastname: Faria
authors.affiliation: Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Bioquímica e Imunologia, Avenida Antônio Carlos, 6627, Pampulha, CEP 31270-901 Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Fernandes Tenório Gomes
authors.initials: FT
authors.lastname: Rodrigues
authors.affiliation: Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Bioquímica e Imunologia, Avenida Antônio Carlos, 6627, Pampulha, CEP 31270-901 Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Ronaldo Alves Pinto
authors.initials: RA
authors.lastname: Nagem
authors.affiliation: Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Bioquímica e Imunologia, Avenida Antônio Carlos, 6627, Pampulha, CEP 31270-901 Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Rubens Daniel Miserani
authors.initials: RD
authors.lastname: Magalhães
authors.affiliation: Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Parasitologia, Avenida Antônio Carlos, 6627, Pampulha, CEP 31270-901 Belo Horizonte, Minas Gerais, Brazil.
authors.forename: João Luís Reis
authors.initials: JL
authors.lastname: Cunha
authors.affiliation: Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Parasitologia, Avenida Antônio Carlos, 6627, Pampulha, CEP 31270-901 Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Daniella Castanheira
authors.initials: DC
authors.lastname: Bartholomeu
authors.affiliation: Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Parasitologia, Avenida Antônio Carlos, 6627, Pampulha, CEP 31270-901 Belo Horizonte, Minas Gerais, Brazil. Electronic address: helida@icb.ufmg.br.
authors.forename: Hélida Monteiro
authors.initials: HM
authors.lastname: de Andrade
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D000953:Antigens, Protozoan / Q000235:genetics; D001938:Brazil; D002353:Carrier State / Q000175:diagnosis / Q000662:veterinary*; D004283:Dog Diseases / Q000175:diagnosis*; D004285:Dogs; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D006801:Humans; D018314:Leishmania infantum / Q000235:genetics / Q000276:immunology*; D007898:Leishmaniasis, Visceral / Q000175:diagnosis* / Q000662:veterinary*; D011994:Recombinant Proteins / Q000235:genetics; D012680:Sensitivity and Specificity; D012698:Serologic Tests / Q000379:methods
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D011994:Recombinant Proteins
keywords: Antigens; Diagnosis; Leishmania infantum; Recombinant proteins; Visceral leishmaniasis