RESEARCH SUMMARY

Our research aims at exploring the functional specialization of dendritic cells derived from monocytes during inflammatory responses caused by infection by bacteria (Listeria monocytogenes), yeasts (Candida albicans) and parasites (Leishmania major) or by allergic reactions induced by plant- (Ole e 1), funghi -(Asp f 1) or acaridae- (Der p 1/2) derived allergens, using mouse experimental models.

In particular our current research interests are focused on the following topics:

• Analysis of the effector functions of mouse monocytes in innate and adaptive immunity

• Analysis of the differential migratory properties of mouse monocyte-derived dendritic cells and macrophages

• Regulation of mouse monocyte differentiation into dendritic cells and macrophages during in vivo immune response to Leishmania major

• Functional specialization of mouse dendritic cells for the induction of Th2 responses against pathogens and allergens

• Gene expression profile of mouse monocytes and monocyte-derived dendritic cells exposed to allergens and Th2-polarizing mediators

• Effect of statin treatment on proinflamatory cytokine production and nitric oxide metabolism by monocyte-derived DCs activated by ligands of TLR receptors or infected by Listeria monocytogenes

• Analysis of the splenic innate immune response to in vivo Listeria monocytogenes infection on statin-treated mice

• Role of type-I interferon in Th17 immune responses against Candida albicans in mice.

The methodology designed for addressing these objectives relies on the following experimental approaches:

• Development of in vitro and in vivo infection models in different mouse strains, including mice deficient in cytokines (GM-CSF), cytokine/chemokine receptors (IFNAR, CCR2, CCR7), molecules involved in dendritic cell activation (MyD88, NOD 1/2, IRF-3, PPAR-gamma) and mice transgenic for TCRs specific for ovalbumin-derived peptides expressed on MHC I (OT-I) or MHC II (OT-II, DO.11)

• Cell biology techniques designed for the purification or isolation of defined cell populations from mouse bone marrow, skin, lymph nodes and spleen, involving magnetic bead and FACS cell separation methods

• Analysis of monocytes, dendritic cells and macrophages from Leishmania- or Listeria- infected mice on cell suspensions or tissue sections, by electron microscopy or confocal microscopy after immunofluorescent staining

• In vitro differentiation of dendritic cells and macrophages on GM-CSF, IL-3, M-CSF or Flt3L-driven cultures from monocytes or bone marrow precursors

• Analysis of gene expression profiles at the protein level by flow cytometry, ELISA and electrophoresis

• Analysis of gene expression at the mRNA level by real-time quantitative PCR, whole mouse genome microarray analyses and chromatin immunoprecipitation.