Antigenic characterization of Trypanosoma evansi using sera from experimentally and naturally infected bovines, equines, dogs, and coatis.

The present research investigated the presence of T. evansi antibodies in animals from the subregion of Nhecolandia, in the Pantanal Sul-mato-grossense, by means of an enzyme linked immunosorbent assay (ELISA) and indirect immunofluorescence antibody test (IFAT), and the pattern of polypeptide recognition by sera from experimentally and naturally infected hosts using Western blotting. Serum samples were obtained from bovines (n = 102), horses (n = 98), and dogs (n = 55), and from 32 free-ranging coatis (Nasua nasua). None of the bovines were found positive, while sera from 16 dogs (29%) and 23 horses (23.4%) were positive by ELISA. Sera from 8 coatis (25%) were found positive using IFAT. Western blotting revealed major polypeptides of T. evansi with molecular weight ranging from 74 to 38 kDa. The polypeptides of 66, 48-46, and 38 kDa were identified by sera from experimentally infected bovines, donkeys, dogs, and coatis. The 48-46 and 38 kDa bands were mainly recognized in chronic phase of infection. The antigen with apparent molecular weight of 66 kDa, revealed by antibodies from all experimental animals, was also recognized in sera of horses and dogs from the Pantanal. The 48-46 kDa polypeptide was identified by antibodies from all naturally infected animals and must be further evaluated for use in specific diagnosis of T. evansi infection.

Antigenic characterization of Trypanosoma evansi using sera from experimentally and naturally infected bovines, equines, dogs, and coatis / Caracterização antigênica do Trypanosoma evansi usando soros de bovinos, equinos, cães e quatis experimentalmente e naturalmente infectados

The present research investigated the presence of T. evansi antibodies in animals from the subregion of Nhecolandia, in the Pantanal Sul-mato-grossense, by means of an enzyme linked immunosorbent assay (ELISA) and indirect immunofluorescence antibody test (IFAT), and the pattern of polypeptide recognition by sera from experimentally and naturally infected hosts using Western blotting. Serum samples were obtained from bovines (n = 102), horses (n = 98), and dogs (n = 55), and from 32 free-ranging coatis (Nasua nasua). None of the bovines were found positive, while sera from 16 dogs (29 percent) and 23 horses (23.4 percent) were positive by ELISA. Sera from 8 coatis (25 percent) were found positive using IFAT. Western blotting revealed major polypeptides of T. evansi with molecular weight ranging from 74 to 38 kDa. The polypeptides of 66, 48-46, and 38 kDa were identified by sera from experimentally infected bovines, donkeys, dogs, and coatis. The 48-46 and 38 kDa bands were mainly recognized in chronic phase of infection. The antigen with apparent molecular weight of 66 kDa, revealed by antibodies from all experimental animals, was also recognized in sera of horses and dogs from the Pantanal. The 48-46 kDa polypeptide was identified by antibodies from all naturally infected animals and must be further evaluated for use in specific diagnosis of T. evansi infection.

O trabalho de pesquisa investigou a presença de anticorpos anti- T. evansi em animais da sub-região da Nhecolândia, no Pantanal sul-mato-grossense, pelo ensaio imunoenzimático (ELISA) e a reação de imunofluorescência indireta (RIFI). O reconhecimento de polipeptídeos de T. evansi foi realizado pela técnica de "Western blotting", utilizando soros de animais experimentalmente e naturalmente infectados. As amostras de soro foram obtidas de bovinos (n = 102), cavalos (n = 98) e cães (n = 55) e de 32 quatis de vida livre (Nasua nasua) do pantanal mato-grossense. Todos os soros dos bovinos foram negativos, enquanto soros de 16 cães (29 por cento) e 23 cavalos (23,4 por cento) foram positivos pelo ELISA. Soros de oito quatis (25 por cento) foram positivos pela RIFI. Pelo "Western-blotting" foi possível revelar polipeptídeos de T. evansi, com peso molecular variando de 74 a 38 kDa. Os polipeptídeos de 66, 48-46 e 38 kDa foram identificados por soros de bovinos, cavalos, cães e quatis experimentalmente infectados. As bandas de 48-46 e 38 kDa foram reconhecidas principalmente na fase crônica da infecção. O antígeno com peso molecular aparente de 66 kDa, revelado por anticorpos de todos os animais experimentais, também foi reconhecido por soros de cavalos e cães do Pantanal. O polipeptídeo de 48-46 kDa foi identificado por anticorpos de todos os animais naturalmente infectados, devendo ser avaliado para o diagnóstico específico da infecção pelo T. evansi.