Interactions between dendritic cells, mast cells and tumor cells.

Author(s)

Cecília Pessoa Rodrigues

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
• Defense date: 2015-03-31

Examining board members

Jose Alexandre Marzagao Barbuto; Niels Olsen Saraiva Câmara; Ramon Kaneno

• Advisor: Jose Alexandre Marzagao Barbuto

Abstract

Mast cells (MC) are tissue resident cells, rich in inflammatory mediators, involved in allergic reactions, and with an increasingly recognized role in immunomodulation. Dendritic cells (DCs), on the other hand, are central to the determination of immune response patterns, being highly efficient antigen-presenting cells that respond promptly to changes in their microenvironment. Here, we show that direct cell contact between iDCs and MC bends DCs towards tolerance induction. These MC-exposed DCs decreased HLA-DR but increased PD-L1 expression and stimulated T lymphocytes to express FoxP3+, to secrete TGF-β and IL-10, and to suppress the proliferation of mitogen-stimulated naïve T lymphocytes. Furthermore, contact with MC induced DCs to express higher levels of indoleamine-2,3-deoxigenase (IDO), a phenomenon that was blocked by treatment of MC with anti-PD-1 or by the treatment of DCs with anti-PD-L1 or PD-L2, but not by blocking of H1 and H2 histamine receptors on DCs. (AU)

• FAPESP's process: 13/08138-1 - Dendritic, mast and tumor cells interaction
• Grantee: Cecilia Pessoa Rodrigues
• Support Opportunities: Scholarships in Brazil - Master