Improved canine and human visceral leishmaniasis immunodiagnosis using combinations of synthetic peptides in enzyme-linked immunosorbent assay.
BACKGROUND
Zoonotic visceral leishmaniasis (VL) is a severe infectious disease caused by protozoan parasites of the genus Leishmania and the domestic dogs are the main urban parasite reservoir hosts. In Brazil, indirect fluorescence antibody tests (IFAT) and indirect enzyme linked immunosorbent assay (ELISA) using promastigote extracts are widely used in epidemiological surveys. However, their sensitivity and specificity have often been compromised by the use of complex mixtures of antigens, which reduces their accuracy allowing the maintenance of infected animals that favors transmission to humans. In this context, the use of combinations of defined peptides appears favorable. Therefore, they were tested by combinations of five peptides derived from the previously described Leishmania diagnostic antigens A2, NH, LACK and K39.


RESULTS
Combinations of peptides derived A2, NH, LACK and K39 antigens were used in ELISA with sera from 44 human patients and 106 dogs. Improved sensitivities and specificities, close to 100%, were obtained for both sera of patients and dogs. Moreover, high sensitivity and specificity were observed even for canine sera presenting low IFAT anti-Leishmania antibody titers or from asymptomatic animals.


CONCLUSIONS
The use of combinations of B cell predicted synthetic peptides derived from antigens A2, NH, LACK and K39 may provide an alternative for improved sensitivities and specificities for immunodiagnostic assays of VL.
Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Belo Horizonte, Minas Gerais, Brasil.
Míriam Maria
MM
Costa
Marcos
M
Penido
Mariana Silva
MS
dos Santos
Daniel
D
Doro
Eloísa
E
de Freitas
Marilene Susan Marques
MS
Michalick
Gabriel
G
Grimaldi
Ricardo Tostes
RT
Gazzinelli
Ana Paula
AP
Fernandes
D000818:Animals; D001938:Brazil; D019411:Clinical Laboratory Techniques / Q000379:methods*; D004283:Dog Diseases / Q000175:diagnosis*; D004285:Dogs; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D006801:Humans; D007159:Immunologic Tests / Q000379:methods; D007898:Leishmaniasis, Visceral / Q000175:diagnosis* / Q000662:veterinary*; D010455:Peptides; D012680:Sensitivity and Specificity
D010455:Peptides