Encephalic inflammatory changes and the correlation with lymphocytes and dendritic cells population in lymphonodes of the head of dogs with visceral leishmaniosis.

Abstract

The infection caused by Leishmania spp. results in a disease that presents a variety of clinical manifestations both in humans and dogs. These manifestations can range from observation of asymptomatic infected dogs to disorders that can result in the death of the host. Chronically infected dogs may show neurological symptoms, however there are few reports that characterize the lesions and elucidate the pathogenesis of visceral leishmaniasis within the central nervous system. In previous projects, it was possible to verify the presence of inflammatory infiltrate in the brain of dogs with leishmaniasis, mainly composed of CD3+ T lymphocytes and an increase in the intensity of labeling of GFAP+ astrocytes and RCA-1+ microglia. With the aim to evaluate the mechanisms involved in the pathogenesis of the brain lesions in these dogs, we propose to characterize the T lymphocytes subsets in the retropharyngeal and submandibular lymph nodes, which are considered to be involved in the brain immune surveillance. T cells will be evaluated by flow cytometry and the phenotypes evaluated will be CD3+, CD4+, CD8+, TCR ±² and TCR ³´. Dendritic cells will be also characterized using MHC-II and CD11c. Histological sections of the brain of the same dogs will also be obtained for evaluation and characterization of brain lesions and detection of T lymphocytes.