Análise morfológica das células de Langerhans purificadas da epiderme de camundongo Balb/c, após interação in vitro com Leishania (Viannia) brasiliensis e Leishamania (Leishmania) amazonensis

Abstract

Langerhans Cells (LC) are MHC class II positive antigen-presenting cells that constitute 2-3% of all epidermal cells, which have been demonstrated to stimulate a vigorous T-cell response to Leishmania major. New World cutaneous leishmaniasis is caused by different species, presenting diverse clinical pictures, varying from cutaneous localized to mucous or anergic disease. Using a "panning" technique, murine (Balb/c) epidermal LC were purified to around 95% purity (pLC). The freshly prepared LC (fLC) presented small, delicate dendrites and the classic Birbeck granules. Parasites of the subgenera Viannia and Leishmania, which are genetically very distinct, have been suggested to have a possible species-specific response in cell mediated immunity. In this study, pLC and L. (V.) braziliensis or L. (L.) amazonensis were cultured and their morfology were analyzed after 12h or 36h culture. Using Giemsa stain and scanning electron microscopy, different morphologic changes were detected on LC afier 12h culture on both cultures, LC and L. (V.) braziliensis or LC and L. (L.) amazonensis. After interaction with L. (V.) braziliensis, LC became more dendritic, that were smaller in lenght when compared to LC cultivated alone. In contrast, after interaction with L. (L.) amazonensis, LC became round shaped with a few cells showing some dendrites. Moreover, there was a dose contact between the promastigotes flagelli and LC, but without phagocytosis in 12h or 36h culture, what is different of the observations found in the literature on the interaction between LC and L. major. These results suggest that LC primary response against different species of Leishmania could be distinct upon the species involved in the interaction process.