Avaliação citopatológica da medula óssea e perfil hematológico de cães naturalmente infectados por Leishmania (Leishmania) chagasiCarla de Oliveira Honse

Foram avaliados quarenta e um cães adultos, machos e fêmeas, sem raça definida, provenientes de inquéritos sorológicos para leishmaniose visceral canina realizados pela Secretaria Municipal de Saúde do Rio de Janeiro. O objetivo deste estudo foi descrever as alterações citopatológicas da medula óssea e o perfil hematológico de cães naturalmente infectados por Leishmania (Leishmania) chagasi. A avaliação citológica da medula óssea incluiu a análise qualitativa e quantitativa. O perfil hematológico foi avaliado através de contador automático de células e esfregaços sanguíneos. Adicionalmente, foram realizadas a imunofenotipagem de linfócitos medulares, pesquisa de formas amastigotas na medula óssea e avaliação dos estoques de ferro medular. De acordo com os resultados obtidos, cães naturalmente infectados por L. (L.) chagasi apresentaram hiperplasia das séries mieloide, linfoide e monocítica, onde frequentemente foram observadas formas amastigotas, anemia normocítica normocrômica e aumento dos estoques de ferro medular Não foram observadas diferenças estatisticamente significativas entre as populações de linfócitos T e linfócitos B medulares. Em conclusão, os cães naturalmente infectados por L. (L.) chagasi apresentaram alterações na medula óssea e no perfil hematológico independentemente da manifestação clínica apresentada pelo animal. Hiperplasia das linhagens hematopoiéticas, anemia, eritrofagocitose e aumento dos estoques de ferro medular possibilitaram uma melhor compreensão dos mecanismos fisiopatológicos envolvidos na doença e a pesquisa de formas amastigotas na medula óssea contribuiu como uma importante ferramenta diagnóstica da leishmaniose visceral canina

Antibacterial and antiparasitic effects of Bothrops marajoensis venom and its fractions: Phospholipase A(2) and L-amino acid oxidase

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Anti-leishmania antibodies in cerebrospinal fluid from dogs with visceral leishmaniasis

Visceral leishmaniasis in Brazil is caused by Leishmania (Leishmania) chagasi and the dog is its most important reservoir. The clinical features in dogs include loss of weight, lymphadenopathy, renal failure, skin lesions, fever, hypergammaglobulinemia, hepatosplenomegaly, anemia, and, rarely, neurological symptoms. Most infected animals develop active disease, characterized by high anti-leishmania antibody titers and depressed lymphoproliferative ability. Antibody production is not primarily important for protection but might be involved in the pathogenesis of tissue lesions. An ELISA test was used to determine if there is an association between neurological symptoms and the presence of anti-L. chagasi antibodies in cerebrospinal fluid (CSF). Thirty serum and CSF samples from symptomatic mixed breed dogs (three with neurological symptoms) from a region of high incidence of visceral leishmaniasis in Brazil were examined for antibody using total parasite antigen and anti-dog IgG peroxidase conjugate. A high level of L. chagasi antibodies was observed in sera (mean absorbance ± SD, 1.939 ± 0.405; negative control, N = 20, 0.154 ± 0.074) and CSF (1.571 ± 0.532; negative control, N = 10, 0.0195 ± 0.040) from all animals studied. This observation suggests that L. chagasi can cause breakdown of filtration barriers and the transfer of antibodies and antigens from the blood to the CSF compartment. No correlation was observed between antibody titer in CSF and neurological symptoms.

Glial reactivity in dogs with visceral leishmaniasis: correlation with T lymphocyte infiltration and with cerebrospinal fluid anti-Leishmania antibody titres

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Antimicrobial activity of an L-amino acid oxidase isolated from Bothrops leucurus snake venom

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Estudo histológico e imunoistoquímico do sistema nervoso central de cães naturalmente infectados por Leishmania (Leishmania) chagasi

The present study aimed to characterize the histopathological alterations and to detect, by immunohistochemistry, the presence of amastigote forms of Leishmania in CNS tissue of dogs with and without neurological clinical signs of the disease. Two groups of animals were used: the first was composed of 18 dogs with visceral leishmaniasis without clinical evidence of neurological involvement, and the second, composed of 21 dogs with visceral leishmaniasis and neurological symptoms. The most frequent histopathological alterations found in the CNS of dogs of both groups were neuronal degeneration with neuronophagia, gliosis, leptomeningitis, vascular congestion, presence of perivascular lymphoplasmacytic infiltrate and areas of focal microhemorrhage. Antigen labeling for whole forms of Leishmania amastigotes was not observed in any fragment of the CNS of the dogs of either groups; however, most of them presented labeling of blood vessels walls, which suggests the presence of circulating parasite antigens.

Avaliação hematológica de cães naturalmente infectados por Leishmania (Leishmania) chagasi submetidos a tratamento com antimoniato de meglumina

The present research was carried out aiming to assess the hematological response of dogs with visceral leishmaniasis submitted to treatment. For this, seven animals naturally infected by Leishmania sp. were submitted to a treatment with 75 mg/kg meglumine antimoniate subcutaneously, 12-12h/3 weeks. In all animals, a complete blood count and bone marrow aspiration biopsy were carried out for a descriptive evaluation at up to seven moments: before the treatment, 30, 60, 90, 120, 150 and 180 days after the start of the treatment. Before the beginning of the experiment hematological alterations were observed in four of the seven dogs (57.1%), among them, nonregenerative anemia, lymphopenia, lymphocytosis and monocytosis. During the course of the experiment the occurrence of leukocytoses, such as left shift neutrophilia and eosinophilia, were observed in some of the animals. Before the beginning of the treatment (M1), the occurrence of erythrocytic hypoplasia was detected by bone marrow cytology in two of the dogs (28.6%). This was reversed through an increase in the amount of erythroid progenitor cells after the administration of meglumine antimoniate. Thus, it can be concluded that the treatment led to normalization of the hematological alterations and recovery of the bone marrow.

Avaliação clínica e parasitológica de cães naturalmente infectados por Leishmania (Leishmania) chagasi submetidos a tratamento com antimoniato de meglumina e alopurinol

Aiming to assess the efficacy of the treatment, to verify the occurrence of possible disease relapses and to search for the presence of parasites after the treatment, seven dogs naturally infected by Leishmania sp., were submitted to a treatment with meglumine antimoniate and allopurinol. For this, lymph node and bone marrow aspiration biopsies were carried out at seven moments. After the end of the six-month observation period all dogs were submitted to euthanasia. Then, spleen and liver imprints and in vitro cultures were carried out to search for amastigote forms of the parasite. All animals presented remission of the symptoms and during all the observation period no dog presented relapse of the disease, although amastigote forms of the parasite were observed in two of the animals at the end of the experiment. Thus, it was possible to conclude that the treatment promotes clinical healing but it does not eliminate the parasites completely.

CD95 (FAS) and CD178 (FASL) induce the apoptosis of CD4+ and CD8+ cells isolated from the peripheral blood and spleen of dogs naturally infected with Leishmania spp

Infected dogs are urban reservoirs of Leishmania chagasi, which is a causative agent of visceral leishmaniasis (VL). Dogs exhibit immune suppression during the course of this disease, and lymphocyte apoptosis is involved in this process. To investigate apoptosis and the expression levels of FAS-FAS-associated death domain protein (CD95 or APO-1), FASL-FAS ligand protein (CD178), and TRAIL-TNF-related apoptosis-inducing ligand (CD253) receptors in peripheral blood mononuclear cells and spleen leukocytes from 38 symptomatic dogs with moderate VL and 25 healthy dogs were evaluated by flow cytometry. The apoptosis rate of blood and splenic CD4+ and CD8+ cells was higher in infected dogs than in healthy dogs. The expression levels of FAS and FASL in blood and splenic CD4+ cells were lower in infected dogs than in healthy dogs. FAS expression in CD8+ cells was higher in infected dogs than in healthy dogs; in contrast, FASL expression was lower in infected dogs. The expression of the TRAIL receptor increased only in splenic CD8+ cells from infected dogs. The FAS and FAS-L blocking antibodies confirmed the importance of these receptors in apoptosis. Our results enhance the current understanding of the immune response in dogs infected with L. chagasi, facilitating the future development of therapeutic interventions to reduce lymphocyte depletion. © 2013 Elsevier B.V.

Avaliação diagnóstica para Leishmania spp. e Trypanosoma cruzi em gatos domésticos procedentes da associação protetora dos animais do município de Ilha Solteira, SP, Brasil

Pós-graduação em Doenças Tropicais - FMB

Caracterização genotípica de amostras de Leishmania spp. isoladas de área endêmica para Leishmaniose Visceral Canina no estado de São Paulo

Pós-graduação em Doenças Tropicais - FMB

Molecular and serological detection of tick-borne pathogens in dogs from an area endemic for Leishmania infantum in Mato Grosso do Sul, Brazil

Patógenos transmitidos por carrapatos atingem uma variedade de hospedeiros vertebrados. Para identificar os agentes patogênicos transmitidos por carrapatos entre cães soropositivos para Leishmania infantum no município Campo Grande-MS, foi realizado um estudo sorológico e molecular para a detecção de Ehrlichia canis, Anaplasma platys e Babesia vogeli em 60 amostras de soro e baço, respectivamente. Adicionalmente, foi realizado o diagnóstico confirmatório de L. infantum por meio de técnicas sorológicas e moleculares. Também foi realizado o alinhamento e análise filogenética das sequências para indicar a identidade das espécies de parasitas que infectam esses animais. Anticorpos IgG anti-Ehrlichia spp., anti-B. vogeli e anti-L. infantum foram detectados em 39 (65%), 49 (81,6%) e 60 (100%) dos cães amostrados, respectivamente. Vinte e sete (45%), cinquenta e quatro (90%), cinquenta e três (88,3%), dois (3,3%) e um (1,6%) cães mostraram-se positivos na PCR para E. canis, Leishmania spp., Leishmania donovani complex, Babesia sp. e Anaplasma sp., respectivamente. Após o seqüenciamento, os amplicons mostraram 99% de similaridade com isolados de E. canis, B. vogeli e A. platys e Leishmania chagasi. Os resultados deste estudo indicaram que os cães soropositivos para L. infantum de Campo Grande, MS, são expostos a vários agentes transmitidos por carrapatos, e, portanto, devem ser incluídos no diagnóstico diferencial em cães com suspeita clínica de leishmaniose.

First detection of Leishmania infantum DNA within the brain of naturally infected dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Molecular detection of Leishmania spp. in road-killed wild mammals in the Central Western area of the State of São Paulo, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

CD95 (FAS) and CD178 (FASL) induce the apoptosis of CD4+ and CD8+ cells isolated from the peripheral blood and spleen of dogs naturally infected with Leishmania spp

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)