Método para análise de aspirado esplênico de cão: desenvolvimento de ferramentas aplicáveis ao monitoramento de variações de populações leucocitárias na Leishmaniose visceral. / A method for the analysis of fine-needle aspirates of canine spleen: development of tools for the monitoring of leukocyte population chages in visceral leishmaniosis.
AUTOR(ES)
Stella Maria Barrouin Melo
DATA DE PUBLICAÇÃO
2005
RESUMO
Introduction: This study was focused on the development of a method for the analysis of the canine spleen as a target organ for diagnostic evaluation, aiming to characterize cellular components of the in situ immune response to infection by Leishmania chagasi, since the dog stands as reservoir of the parasite in endemic areas of the disease. Methods: The study was developed in a sequence of experiments, involving healthy dogs and dogs with canine visceral leishmaniosis(CVL), to: (i) determine the sensitivity of confirmative parasitological diagnosis, comparatively using samples of spleens and popliteal lymph nodes from 64 seropositive animals for antibodies anti-Leishmania; (ii) evaluate the safety of the fine-needle biopsy of canine spleen as a sampling procedure for laboratory analysis, by performing the technique on 209 dogs with a wide variety of clinical conditions of CVL, from absence of signs to a terminal picture of disease; and (iii) standardize and validate procedures for the analysis of spleen samples by means of cytochemical staining, with Wrights and hematoxilin-eosin techniques, and immunocytochemistry using monoclonal antibodies, applying them in the evaluation of the cellular splenic composition of 14 healthy non-infected dogs and 15 dogs with CVL. Results: In the first approach, our results, demonstrating 73% of Leishmania detection rate in spleen samples, in comparison with the 18% rate in lymph node cultures, supported the use of spleen instead of lymph node as the organ of choice for the parasitological diagnosis of the disease. Then, the evaluation of the potential risks of the fine needle spleen biopsy showed that the procedure did not cause adverse side effects and could be considered efficacious and safe for providing samples for laboratorial analysis of cells of the canine immune system in this organ. Afterwards, the standardized techniques allowed the distinction of significant differences among leukocyte populations from blood and spleen in both dog groups, including changes associated to disease. All results are discussed. Conclusion: The evaluation of spleen aspirates with the method described herein constitute a potential contribution to the study of the canine immune system, having the perspective of being applied as an analytical tool for the monitoring the immune response in the canine spleen in research for the development of immunotherapy or vaccine against CVL.
ASSUNTO(S)
imunologia imunoquímica immunochemistry dog populações leucocitárias aspirado esplênico leukocyte populations cytochemistry citoquímica visceral leismaniosis leishmaniose visceral cão spleen aspirates
