Deral de S Paulo UNIFESP, Sao Paulo, Brazil; 4Departamento de Ci cias Farmac ticas, Universidade Federal de S Paulo campus Diadema, Sao Paulo, BrazilPF09.Characterisation of extracellular vesicles released by Leishmania amazonensis and its role on macrophages activation Fernanda MC. Barbosa1, Mayte dos S. Toledo1, Talita V. Dupin1, Kleber S. Ribeiro2, Andre Cronemberger-Andrade3, Alison FA. Chaves2, Ana Cl dia Torrecilhas4 and Patricia X. Batista5 Universidade Federal de S Paulo campus Diadema, Sao Paulo, Brazil; Universidade Federal de S Paulo, Sao Paulo, Brazil; 3UNIFESP; four Universidade Federal de S Paulo UNIFESP, Sao Paulo, Brazil; five Departamento de Ci cias Farmac ticas, Universidade Federal de S Paulo campus Diadema, Sao Paulo, Brazil2Immune cells can release distinctive type of extracellular vesicles (EVs) which are relevant automobiles of intercellular communication. EVs targeted various forms of immune cells and are involved in immune regulation according to the context. B-1 cells are a subtype of B lymphocytes with peculiar functions in immunity. These cells are capable to create regulatory cytokines (mainly IL10), natural antibodies and differentiate into phagocytic cells. Within this study we evaluated the ability of B-1 cells in producing extracellular vesicles within the presence or absence of L. amazonensis promastigotes and their influence on macrophages activation. Our outcomes showed that B-1 cells spontaneously released EVs but there were improve in releasing immediately after 24 or 48 h of in vitro infection, as demonstrated by nanoparticle tracking evaluation and scanning electron microscopy. Macrophages from BALB/c mice treated with EVs from infected B-1 cells led to a substantial boost in IL-6 and IL-10, as in comparison with the cells stimulated with EVs released by non-infected B-1 cells. No differences have been observed to TNF-alpha and iNOS. These macrophages did not alter the phagocytic index (PI) immediately after treatment with EVs from infected or non-infected B-1 cells. To macrophages from C57BL/6 mice we observed a considerable reduction in the expression of IL-10 and iNOS but the expression of IL-6 and TNF-alpha were improved in macrophages stimulated with EVs from infected B-1 cells, as compared to macrophages stimulated with EVs released by non-infected B-1 cells. In addition, these macrophages treated with EVs from infected B-1 cells have a considerable enhance within the phagocytic index as when compared with the same cells stimulated with EVs from non-infected B-1 cells. Our function showed that B-1 cells are in a position to release EVs however the infection stimulated a rise in their production. These EVs Ubiquitin-Specific Peptidase 43 Proteins manufacturer modulated the expression of some cytokines and iNOS on macrophages and led an increase in PI in macrophages from C57BL/6 mice.PF09.Unravelling the exosome pathway in the human pathogen leishmania Vanessa Diniz Atayde and Martin Olivier McGill University, Montreal, CanadaExtracellular vesicles (EVs) are released by quite a few CBL-C Proteins Purity & Documentation pathogens. These EVs execute numerous functions, including delivering molecules that execute effector activity on host cells. Some studies have demonstrated that EVs released by some species of Leishmania seem to contribute towards the establishment of infection and immunomodulation. Nevertheless, studies have not been performed to verify the role of EVs produced by L. amazonensis (specie responsible for cutaneous leishmaniasis in Brazil) inside the activation and/or modulation of phagocytic cells from the immune system and disease progression. This function aimed to char.