Resultado da pesquisa (3)

Termo utilizado na pesquisa IFAT

#1 - Performance of the Dot-blot test method for detecting antibodies to Sarcocystis spp. in cattle

Abstract in English:

Serological techniques can detect antibodies against Sarcocystis spp., Neospora caninum and Toxoplasma gondii antigens in single or mixed infections. Immunofluorescent antibody tests (IFAT) is considered the gold standard technique for Sarcocystosis diagnostic in cattle serum and a positive IFAT result reflects Sarcocystis spp. infection. Therefore, the aims of the present study were to compare IFAT and Dot-blot for sarcocystosis diagnostic in experimentally infected mice and to investigate serological cross-reactions with N. caninum and T. gondii in these methods. Mice (Mus musculus) were inoculated intraperitoneally with bradizoites of Sarcocystis spp. or tachyzoites of N. caninum or T. gondii. Serum samples were obtained and analyzed by IFAT and Dot-blot for the three protozoa. Serum from N. caninum and T. gondii experimentally infected mice were tested by IFAT and reacted only to N. caninum or T. gondii antigens, respectively. Specific antibodies against Sarcocystis spp. were present in all animals experimentally infected with this protozoan, with IFAT titers from 10 to 800. Serum samples from mice experimentally infected with Sarcocystis spp., N. caninum and T. gondii and tested by Dot-blot demonstrated no cross reaction between protozoa. A Dot-blot using Sarcocystis spp. antigen appears to be a good alternative to IFAT in the serological diagnosis of Sarcocystosis.

Abstract in Portuguese:

As técnicas sorológicas podem detectar anticorpos contra os antígenos de Sarcocystis spp., Neospora caninum e Toxoplasma gondii em infecções únicas ou mistas. O teste de anticorpos imunofluorescentes (IFAT) é considerado a técnica padrão-ouro para o diagnóstico de sarcocistose no soro de bovinos e um resultado positivo de IFAT reflete Sarcocystis spp. infecção. Portanto, os objetivos do presente estudo foram comparar IFAT e Dot-blot para diagnóstico de sarcocistose em camundongos infectados experimentalmente e investigar reações cruzadas sorológicas com N. caninum e T. gondii nesses métodos. Os camundongos (Mus musculus) foram inoculados intraperitonealmente com bradizoítos de Sarcocystis spp. ou taquizoítos de N. caninum ou T. gondii. As amostras de soro foram obtidas e analisadas por IFAT e Dot-blot para os três protozoários. O soro de N. caninum e T. gondii infectados experimentalmente foram testados por IFAT e reagiram apenas aos antígenos de N. caninum ou T. gondii, respectivamente. Anticorpos específicos contra Sarcocystis spp. estavam presentes em todos os animais experimentalmente infectados com este protozoário, com títulos de IFAT de 10 a 800. Amostras de soro de camundongos infectados experimentalmente com Sarcocystis spp., N. caninum e T. gondii e testadas por Dot-blot não demonstraram reação cruzada entre protozoários. Um Dot-blot usando Sarcocystis spp. O antígeno parece ser uma boa alternativa ao IFAT no diagnóstico sorológico da sarcocistose.


#2 - Molecular and serological detection of Leishmania spp. in horses from an endemic area for canine visceral leishmaniasis in southeastern Brazil

Abstract in English:

This study aimed to verify the occurrence of Leishmania spp. and Leishmania (Leishmania) infantum in horses from a visceral leishmaniasis endemic area in Brazil. DNA samples from blood and conjunctival swab (CS) were tested by PCR and Indirect Immunofluorescence Antibody Test (IFAT). Although none of the horses was clinically sick, animals infected by Leishmania spp. were found and some could be characterized as infected by L. (L.) infantum. From 40 horses, 100% of the animals were positive by blood PCR, 90% (36/40) by CS PCR, and 2.5% (01/40) in serodiagnosis, by IFAT. Six from these 40 horses were L. (L.) infantum positive by blood PCR. Direct sequencing and analysis of amplicons resulted in a sequence to evolutionary analysis. Results indicate the presence of Leishmania spp. and L. (L.) infantum infecting healthy horses in Brazil. The presence of Leishmania spp. and L. (L.) infantum DNA in asymptomatic horses suggests that they can be important reservoirs of these parasites, a highly relevant finding for the epidemiological surveillance of the diseases they cause.

Abstract in Portuguese:

O estudo objetivou verificar a ocorrência de Leishmania spp. e Leishmania (Leishmania) infantum em cavalos de uma região endêmica para leishmaniose visceral do Brasil. Amostras de DNA de sangue e suabe conjuntival (SC) foram testadas pela PCR e pela Reação de Imunofluorescência Indireta (RIFI). Embora nenhum cavalo estivesse clinicamente doente, animais infectados por Leishmania spp. e L. (L.) infantum foram encontrados em Ilha Solteira/SP. Dos 40 cavalos, 100% (40/40) foram positivos pela PCR de sangue, 90% (36/40) pela PCR de SC, e 2,5% (01/40) no sorodiagnóstico, pela RIFI. Seis desses 40 cavalos foram positivos para L. (L.) infantum pela PCR de sangue. O sequenciamento direto e a análise dos amplicons resultaram em uma sequência para análise evolutiva. Os resultados indicam a presença de Leishmania spp. e L. (L.) infantum infectando cavalos saudáveis no Brasil. A presença de DNA de Leishmania spp. and L. (L.) infantum em cavalos saudáveis sugere que eles podem ser importantes reservatórios desses parasitas, um achado altamente relevante para a vigilância epidemiológica das doenças que causam.


#3 - Evaluation of the indirect fluorescent antibody test and modified agglutination test for detection of antibodies against Toxoplasma gondii in experimentally infected pigs

Abstract in English:

Minho A.P., Navarro I.T., Freire R.L., Vidotto O., Gennari S.M., Marana E.M. & Garcia J.L. 2004. Evaluation of the indirect fluorescent antibody test and modified agglutination test for detection of antibodies against Toxoplasma gondii in experimentally infected pigs. Pesquisa Veterinária Brasileira 24(4):199-202. Depto Medicina Veterinária Preventiva, Universidade Estadual de Londrina, Cx. Postal 6001, Londrina, PR 86050-970, Brazil. E-mail: italmar@uel.br The study determined the sensitivity and specificity of the indirect fluorescent antibody test (IFAT) and modified agglutination test (MAT) for anti-Toxoplasma gondii antibody detection by analyzing sera from 46 experimentally infected pigs. Values for sensitivity were 95.7% (confidence interval 95%: 84.0-99.2%) and for specificity 97.8% (confidence interval 95%: 87.0-99.9%) in both tests. There was an optimum agreement of results between IFAT and MAT evidenced by a Kappa test of 0.86. These results validate these tests for the detection of T. gondii infection in pigs. IFAT and MAT despite methodologies with different characteristics and readings have similar accuracy in pig serum samples.

Abstract in Portuguese:

Minho A.P., Navarro I.T., Freire R.L., Vidotto O., Gennari S.M., Marana E.M. & Garcia J.L. 2004. Evaluation of the indirect fluorescent antibody test and modified agglutination test for detection of antibodies against Toxoplasma gondii in experimentally infected pigs. Pesquisa Veterinária Brasileira 24(4):199-202. Depto Medicina Veterinária Preventiva, Universidade Estadual de Londrina, Cx. Postal 6001, Londrina, PR 86050-970, Brazil. E-mail: italmar@uel.br The study determined the sensitivity and specificity of the indirect fluorescent antibody test (IFAT) and modified agglutination test (MAT) for anti-Toxoplasma gondii antibody detection by analyzing sera from 46 experimentally infected pigs. Values for sensitivity were 95.7% (confidence interval 95%: 84.0-99.2%) and for specificity 97.8% (confidence interval 95%: 87.0-99.9%) in both tests. There was an optimum agreement of results between IFAT and MAT evidenced by a Kappa test of 0.86. These results validate these tests for the detection of T. gondii infection in pigs. IFAT and MAT despite methodologies with different characteristics and readings have similar accuracy in pig serum samples.


Colégio Brasileiro de Patologia Animal SciELO Brasil CAPES CNPQ UNB UFRRJ CFMV