RESUMO

BALB/c mice were experimentally infected with L. (L.) chagasi and immunosuppressed for the study of the histopathological changes present in their liver. The 96 studied mice were subdivided into four groups: control (I) no treatment; immunosuppressed (II) treatment with dexamethasone (DXM) and pentoxifylline (PTX); infected (III) infection with L. (L.) chagasi; and infected and immunosuppressed (IV) - infection with L. (L.) chagasi and treatment with DXM and PTX. The day of infection was considered the day zero and immunosuppression occurred at 60 days P.I. Samples were obtained at distinct moments, 15, 30, 60, 75 and 90 days P.I., by collecting liver fragments for histopathological assessment. There was progressive and constant inflammatory reaction of inflammatory infiltrate and complete granulomas, which was renewed in all observation phases. For inoculated groups, the presence of amastigotes was confirmed by means of immunohistochemistry. The immunosuppressed group showed weak inflammatory reaction and rare incomplete granulomas. Immunosuppression influenced the immune response of the liver, which is capable of controlling murine visceral leishmaniasis.(AU)

Camundongos BALB / c foram infectados experimentalmente com L. (L.) chagasi e imunossuprimidos para estudar as alterações histopatológicas no fígado presente. Os 96 ratos estudados foram divididos em quatro grupos: controle (I) - sem tratamento; imunossuprimidos (II) - O tratamento com dexametasona (DXM) e pentoxifilina (PTX); infectado (III) - infecção por L. chagasi (L.); e infectados e imunodeprimidos (IV) - infecção por L. chagasi (L.) e tratamento com DXM e PTX. O dia da infecção foi considerado o dia zero e imunossupressão ocorreu 60 dias P.I. As amostras foram obtidas em vários momentos, 15, 30, 60, 75 e 90 dias P.I., por coleta de fragmentos de fígado para avaliação histopatológica. Houve constante reação inflamatória e infiltrado inflamatório progressivo e granulomas completos, que foi renovado em todas as fases de observação. Para os grupos inoculados, a presença de amastigotas foi confirmada por imuno-histoquímica. O grupo de imunodeprimidos apresentou uma resposta inflamatória fraca e granulomas raros e incompletos. Imunossupressão influenciou a resposta imune do fígado, que é capaz de controlar a leishmaniose visceral murina.(AU)

Ratones BALB / c se infectaron experimentalmente con L. chagasi (L.) y inmunosuprimidos para el estudio de los cambios histopatológicos presentes en su hígado. Los 96 ratones estudiados se dividieron en cuatro grupos: control (I) - sin tratamiento; inmunosuprimidos (II) - El tratamiento con dexametasona (DXM) y pentoxifilina (PTX); infectada (III) - la infección con L. chagasi (L.); y infectada y inmunosuprimidos (IV) - infección con L. chagasi (L.) y el tratamiento con DXM y PTX. El día de la infección fue considerado como el día cero y la inmunosupresión se produjo a 60 días P.I. Las muestras se obtuvieron en momentos distintos, 15, 30, 60, 75 y 90 días P.I., mediante la recopilación de fragmentos de hígado para la evaluación histopatológica. Hubo reacción inflamatoria progresiva y constante de infiltrado inflamatorio y granulomas completos, que fue renovado en todas las fases de observación. Para los grupos inoculados, la presencia de amastigotes se confirmó por medio de inmunohistoquímica. El grupo inmunosuprimidos mostró una reacción inflamatoria débil y granulomas incompletas raras. Inmunosupresión influyó en la respuesta inmune del hígado, que es capaz de controlar la leishmaniosis visceral murino.(AU)

Assuntos

RESUMO

BALB/c mice were experimentally infected with L. (L.) chagasi and immunosuppressed for the study of the histopathological changes present in their liver. The 96 studied mice were subdivided into four groups: control (I) – no treatment; immunosuppressed (II) – treatment with dexamethasone (DXM) and pentoxifylline (PTX); infected (III) – infection with L. (L.) chagasi; and infected and immunosuppressed (IV) - infection with L. (L.) chagasi and treatment with DXM and PTX. The day of infection was considered the day zero and immunosuppression occurred at 60 days P.I. Samples were obtained at distinct moments, 15, 30, 60, 75 and 90 days P.I., by collecting liver fragments for histopathological assessment. There was progressive and constant inflammatory reaction of inflammatory infiltrate and complete granulomas, which was renewed in all observation phases. For inoculated groups, the presence of amastigotes was confirmed by means of immunohistochemistry. The immunosuppressed group showed weak inflammatory reaction and rare incomplete granulomas. Immunosuppression influenced the immune response of the liver, which is capable of controlling murine visceral leishmaniasis.

Camundongos BALB / c foram infectados experimentalmente com L. (L.) chagasi e imunossuprimidos para estudar as alterações histopatológicas no fígado presente. Os 96 ratos estudados foram divididos em quatro grupos: controle (I) - sem tratamento; imunossuprimidos (II) - O tratamento com dexametasona (DXM) e pentoxifilina (PTX); infectado (III) - infecção por L. chagasi (L.); e infectados e imunodeprimidos (IV) - infecção por L. chagasi (L.) e tratamento com DXM e PTX. O dia da infecção foi considerado o dia zero e imunossupressão ocorreu 60 dias P.I. As amostras foram obtidas em vários momentos, 15, 30, 60, 75 e 90 dias P.I., por coleta de fragmentos de fígado para avaliação histopatológica. Houve constante reação inflamatória e infiltrado inflamatório progressivo e granulomas completos, que foi renovado em todas as fases de observação. Para os grupos inoculados, a presença de amastigotas foi confirmada por imuno-histoquímica. O grupo de imunodeprimidos apresentou uma resposta inflamatória fraca e granulomas raros e incompletos. Imunossupressão influenciou a resposta imune do fígado, que é capaz de controlar a leishmaniose visceral murina.

Ratones BALB / c se infectaron experimentalmente con L. chagasi (L.) y inmunosuprimidos para el estudio de los cambios histopatológicos presentes en su hígado. Los 96 ratones estudiados se dividieron en cuatro grupos: control (I) - sin tratamiento; inmunosuprimidos (II) - El tratamiento con dexametasona (DXM) y pentoxifilina (PTX); infectada (III) - la infección con L. chagasi (L.); y infectada y inmunosuprimidos (IV) - infección con L. chagasi (L.) y el tratamiento con DXM y PTX. El día de la infección fue considerado como el día cero y la inmunosupresión se produjo a 60 días P.I. Las muestras se obtuvieron en momentos distintos, 15, 30, 60, 75 y 90 días P.I., mediante la recopilación de fragmentos de hígado para la evaluación histopatológica. Hubo reacción inflamatoria progresiva y constante de infiltrado inflamatorio y granulomas completos, que fue renovado en todas las fases de observación. Para los grupos inoculados, la presencia de amastigotes se confirmó por medio de inmunohistoquímica. El grupo inmunosuprimidos mostró una reacción inflamatoria débil y granulomas incompletas raras. Inmunosupresión influyó en la respuesta inmune del hígado, que es capaz de controlar la leishmaniosis visceral murino.

Assuntos

RESUMO

The interest in commercial use of wild animals is increasing, especially regarding raising of capybaras. Although this wild species is potentially lucrative for the production of meat, oil and leather, it is suggested as a probable reservoir of leptospires. Methods Due to the economic importance of this species and the lack of studies concerning leptospirosis, the presence of anti-leptospirosis agglutinins was assayed in 55 serum samples of capybaras (Hydrochoerus hydrochaeris) from commercial and experimental breeding flocks located in São Paulo state, Paraná state, and Rio Grande do Sul state, Brazil. Samples were obtained through cephalic or femoral venipunction (5 to 10 mL). Microscopic agglutination test was used according to the Brazilian Health Ministry considering as cut-off titer of 100. Results Out of the 55 samples analyzed, 23 (41.82 %) tested positive. The most prevalent serovar was Icterohaemorrhagiae (56.52 %) in 13 samples, followed by Copenhageni in nine samples (39.13 %), Pomona in four samples (17.39 %), Djasiman and Castellonis in three samples each (13.04 %), Grippotyphosa, Hardjo, Canicola, and Cynopteri in two samples each (8.7 %), and Andamana and Bratislava in one sample each (4.34 %). Conclusions These results suggest the evidence of exposure toLeptospira spp. and the need of new studies to evaluate a higher number of capybaras from different regions to better understand the importance of leptospirosis infection in these animals and verify the zoonotic role of this species as a possible source of infection to humans and other animals.(AU)

Assuntos

RESUMO

Abstract Background The interest in commercial use of wild animals is increasing, especially regarding raising of capybaras. Although this wild species is potentially lucrative for the production of meat, oil and leather, it is suggested as a probable reservoir of leptospires. Methods Due to the economic importance of this species and the lack of studies concerning leptospirosis, the presence of anti-leptospirosis agglutinins was assayed in 55 serum samples of capybaras (Hydrochoerus hydrochaeris) from commercial and experimental breeding flocks located in São Paulo state, Paraná state, and Rio Grande do Sul state, Brazil. Samples were obtained through cephalic or femoral venipunction (5 to 10 mL). Microscopic agglutination test was used according to the Brazilian Health Ministry considering as cut-off titer of 100. Results Out of the 55 samples analyzed, 23 (41.82 %) tested positive. The most prevalent serovar was Icterohaemorrhagiae (56.52 %) in 13 samples, followed by Copenhageni in nine samples (39.13 %), Pomona in four samples (17.39 %), Djasiman and Castellonis in three samples each (13.04 %), Grippotyphosa, Hardjo, Canicola, and Cynopteri in two samples each (8.7 %), and Andamana and Bratislava in one sample each (4.34 %). Conclusions These results suggest the evidence of exposure toLeptospira spp. and the need of new studies to evaluate a higher number of capybaras from different regions to better understand the importance of leptospirosis infection in these animals and verify the zoonotic role of this species as a possible source of infection to humans and other animals.

Assuntos

RESUMO

The interest in commercial use of wild animals is increasing, especially regarding raising of capybaras. Although this wild species is potentially lucrative for the production of meat, oil and leather, it is suggested as a probable reservoir of leptospires. Methods Due to the economic importance of this species and the lack of studies concerning leptospirosis, the presence of anti-leptospirosis agglutinins was assayed in 55 serum samples of capybaras (Hydrochoerus hydrochaeris) from commercial and experimental breeding flocks located in São Paulo state, Paraná state, and Rio Grande do Sul state, Brazil. Samples were obtained through cephalic or femoral venipunction (5 to 10 mL). Microscopic agglutination test was used according to the Brazilian Health Ministry considering as cut-off titer of 100. Results Out of the 55 samples analyzed, 23 (41.82 %) tested positive. The most prevalent serovar was Icterohaemorrhagiae (56.52 %) in 13 samples, followed by Copenhageni in nine samples (39.13 %), Pomona in four samples (17.39 %), Djasiman and Castellonis in three samples each (13.04 %), Grippotyphosa, Hardjo, Canicola, and Cynopteri in two samples each (8.7 %), and Andamana and Bratislava in one sample each (4.34 %). Conclusions These results suggest the evidence of exposure toLeptospira spp. and the need of new studies to evaluate a higher number of capybaras from different regions to better understand the importance of leptospirosis infection in these animals and verify the zoonotic role of this species as a possible source of infection to humans and other animals.

Assuntos

RESUMO

INTRODUCTION: Leishmaniasis and toxoplasmosis are important to public health. METHODS: Antibodies for Toxoplasma gondii and Leishmania spp. were evaluated in cats from Campo Grande, State of Mato Grosso do Sul, Brazil, a region endemic for canine visceral leishmaniasis. Serum samples from 50 asymptomatic cats were titrated for T. gondii by the immunofluorescence antibody test and modified agglutination test and for Leishmania spp. by the immunofluorescence antibody test. RESULTS: These two agents coinfected two (4%) of the 50 tested animals. CONCLUSIONS: These findings demonstrate the concomitant presence of two important zoonoses in cats from Brazilian endemic regions for canine visceral leishmaniasis.

Assuntos

RESUMO

O objetivo do estudo foi avaliar a resposta humoral, a carga parasitária e os aspectos histopatológicos presentes no fígado em camundongos BALB/c experimentalmente infectados por L. (L.) chagasi e imunossuprimidos. 96 camundongos foram subdivididos em quatro grupos: controle (I) – sem tratamento; imunossuprimidos (II) – tratamento com dexametasona (DXM) e pentoxifilina (PTX); infectado (III) – infecção por L (L.) chagasi e infectados e imunossuprimidos (IV) - infecção por L (L.) chagasi e tratados com DXM e PTX. O dia de infecção foi considerado como o dia zero e a imunossupressão ocorreu 60 dias pós-infecção. As amostras foram obtidas de cada grupo, em momentos distintos 15, 30, 60, 75 e 90 dias pós-infecção, em que se coletou sangue total, para detecção de IgG1 e IgG2a pelo ensaio imunoenzimático (ELISA), fragmentos de baço e fígado, para detecção da carga parasitária pela técnica de microtitulação em cultura e fragmentos de fígado para o exame histopatológico. Houve diferença significativa na produção das imunoglobulinas e IgG1 foi à subclasse de imunoglobulina mais produzida pelos grupos (P < 0,0001). Quando comparadas a subclasses de imunoglobulinas dentro do mesmo grupo, IgG1 também apresentou médias maiores de produção nos grupos III e IV (P = 0,014 e P = 0,009). E quando se considera o momento, não houve diferenças significativas entre IgG1 e IgG2a. Aos 90 dias pós-infecção foram encontradas diferenças significativas entre as médias de produção de IgG1 e IgG2a, entre os grupos III e IV e o grupo III produziu mais as duas subclasses (P = 0,02). Nos momentos 75 e 90 dias pós-infecção houve produção maior de IgG1 e IgG2a. O Grupo IV apresentou maior carga parasitária (P < 0,005).(...)

This study aimed to evaluate the humoral response, the parasite load and liver histopathological features in BALB/c experimentally infected by L. (L.) chagasi and immunosuppressed Ninety-six mice divided into four groups: control (I) - no treatment; immunosuppressed (II) - Treatment with dexamethasone (DXM) and pentoxifylline (PTX), infected (III) - infection by L. (L.) chagasi and infected and immunosuppressed (IV) - infection by L (L.) chagasi and treated with PTX and DXM. The days of infection was considered as day zero and immunosuppression occurred 60 days post-infection. Samples were obtained from each group at different times 15, 30, 60, 75 and 90 days post-infection, which collected whole blood for detection of IgG1 and IgG2a by test immunoassay (ELISA), fragments of spleen and liver, to detect the parasite load in the technique microtiter culture and fragments of liver for histopathology. Significant differences in production of immunoglobulins, IgG1 was the subclass immunoglobulin produced by most groups (P<0.0001). When comparing the immunoglobulin subclasses within the same group, IgG1 also showed higher average production in groups III and IV (P=0.014 and P=0.009). When one considers the time, there were no significant differences between IgG1 and IgG2a. At 90 days post-infection were significant differences between the means of production of IgG1 and IgG2a between group III and IV and group III produced over the two subclasses (P=0.02). In periods of 75 and 90 days post-infection there was increased production of IgG1 and IgG2a. Group IV showed a higher parasite load (P <0.005).(...)

Assuntos

RESUMO

The aims of this study were to evaluate the immunomodulatory role of TGF-beta1, IL-10, and INF-gamma in spleen and liver extracts and supernatant cultures of white spleen cells from male symptomatic and asymptomatic dogs, naturally infected by Leishmania (Leishmania) chagasi. Thirty dogs from Araçatuba, São Paulo, Brazil, an endemic leishmaniosis area, were selected by positive ELISA serological reaction for Leishmania sp. and divided into two groups: asymptomatic (n=15) and symptomatic (n=15) consisting of animals with at least three characteristic signs (fever, dermatitis, lymphoadenopathy, onychogryphosis, weight loss, cachexia, locomotion problems, conjunctivitis, epistaxis, hepatosplenomegaly, edema, and apathy). After euthanasia, spleen and liver fragments were collected for ex vivo quantification of TGF-beta1, IL-10, and INF-gamma. Naturally active in vitro produced TGF-beta1 was also evaluated in spleen cell culture supernatant. Spleen and liver extract of asymptomatic dogs had higher mean TGF-beta1 levels than symptomatic dogs. High concentrations of IL-10 were found in spleen, and mainly in liver extract of both groups. Higher INF-gamma concentrations were found in spleen extracts of symptomatic dogs, and in liver extracts of asymptomatic dogs. Extract of this cytokine was lower in spleen extract. Although INF-gamma is being produced in canine infection, mean levels of TGF-beta1 and IL-10 from spleen and liver extracts were quantitatively much higher; suggesting that immune response in both asymptomatic and symptomatic dogs was predominantly type Th2.

Assuntos

RESUMO

Um ensaio de imunoadsorção enzimática para detecção de anticorpos contra Leishmania chagasi, utilizando antígeno total de formas promastigotas lisados foi desenvolvido. Cinqüenta cães com sintomas clínicos de leishmaniose visceral foram examinados. Esta técnica utilizou anti-IgG de cão conjugado a peroxidase ou proteína A conjugado a peroxidase. Foi verificado que nos animais positivos diagnosticados por exame parasitológico direto o ensaio ELISA utilizando proteína A conjugada a peroxidase (média da densidade óptica + ou - desvio padrão 2,078 + ou - 0,631) detecta mais anticorpos do que o sistema utilizando anti-IgG de cão conjugado a peroxidase (média da densidade óptica + ou - desvio padrão 1,008 + ou - 0,437), enquanto para os animais negativos o resultado obtido nos dois sistemas de detecção são similares. Esse resultado sugere que o sistema de ELISA utilizando proteína A conjugado a peroxidase pode ser útil na detecção de animais na fase aguda da infecção e desta forma auxiliar na identificação dos animais positivos e no controle desta importante zoonose. (AU)

A rapid indirect enzyme-linked immunosorbent assay (ELISA) was developed for measuring antibodies against Leishmania chagasi using total antigen from lysed promastigotes. Fifty symptomatic mixed breed dogs from a region of high incidence of visceral leishmaniasis in Brazil were examined. The results showed that in the positive animals, diagnosed by cytological examination, the ELISA using protein A assay system (mean optical density ± SD / 2.078 ± 0.631) detected more antibodies than the anti-IgG assay (mean optical density ± SD / 1.008 ± 0.437), while in the negative animals, the results by both systems were similar. These results suggest that the ELISA assay using protein A peroxidase conjugated could be useful to detect early infected animals in endemic areas, and thus help to control the spread of the infection.(AU)

Assuntos

RESUMO

Um ensaio de imunoadsorção enzimática para detecção de anticorpos contra Leishmania chagasi, utilizando antígeno total de formas promastigotas lisados foi desenvolvido. Cinqüenta cães com sintomas clínicos de leishmaniose visceral foram examinados. Esta técnica utilizou anti-IgG de cão conjugado a peroxidase ou proteína A conjugado a peroxidase. Foi verificado que nos animais positivos diagnosticados por exame parasitológico direto o ensaio ELISA utilizando proteína A conjugada a peroxidase (média da densidade óptica ± desvio padrão 2,078 ± 0,631) detecta mais anticorpos do que o sistema utilizando anti-IgG de cão conjugado a peroxidase (média da densidade óptica ± desvio padrão 1,008 ± 0,437), enquanto para os animais negativos o resultado obtido nos dois sistemas de detecção são similares. Esse resultado sugere que o sistema de ELISA utilizando proteína A conjugado a peroxidase pode ser útil na detecção de animais na fase aguda da infecção e desta forma auxiliar na identificação dos animais positivos e no controle desta importante zoonose.

Assuntos