Interação entre Angiostrongylus vasorum e Ancylostoma caninum: aspectos parasitológicos, hematológicos e imunológicos em cães experimentalmente infectados

Abstract

vasorum and Ancylostoma caninum are dogs parasites that are widely geographically distributed and has an important role both in the clinical aspect of veterinary and public health, since they can cause great morbidity in dogs and be the cause of zoonoses. In order to evaluate parasitological, haematological and immunological changes due to coinfection by these helminths, 19 mongrel dogs of both sexes and aged 22 months were followed. The animals were divided into four groups (A, B, C and D): Group A with four dogs uninfected group B with 5 dogs with chronic angiostrongylosis, group C with 5 dogs with chronic angiostrongylosis that were infected with A. caninum and group D with 5 dogs infected simultaneously with A. vasorum and A. caninum. The parasitological monitoring was performed by counting of eggs and larvae per gram of feces. Haematological abnormalities were evaluated by blood counts. To evaluate the cellular immune response during infection, peripheral blood mononuclear cells were collected and analyzed for proliferative capacity in vitro against the parasite antigen stimulation technique by MTT; cytokine production in vitro after stimulation with antigen by ELISA and for identification of subpopulations of leukocytes in the peripheral blood ex vivo by flow cytometry. To evaluate the humoral immune plasma of dogs were analyzed by indirect ELISA technique in search of IgG and IgE specific for antigens of A. vasorum and A. caninum. Data analysis showed that dogs coinfected A. vasorum and A. caninum had fewer counts of larvae per gram of feces compared to the group infected with only A. vasorum. Eosinophilia, neutrophilia, lymphocytosis and thrombocytopenia were observed in the infected groups. There was no difference in cell proliferation in vitro susceptibility to antigenic stimuli of parasites between infected and uninfected groups. In dogs infected with A. vasorum was observed a Th2 immune response in dogs and coinfected a mixed profile of Th1 and Th2. In the infected groups was detected a higher percentage of CD3 + CD4 + circulating T lymphocytes compared to CD3 + CD8 +, CD21 + B lymphocytes and CD14 + monocytes. Regarding to immunoglobulin analyzed, a higher level in the production of IgG was observed during acute infection and IgE during the chronic phase, but no significant difference between these values. After this work, we can infer that coinfection by A. caninum in dogs causes changes to aspects angiostrongylosis parasitological, hematological and immunological in experimentally infected dogs.