CD83 overexpression on Melan-A/MART-1-specific tumor-infiltrating lymphocytes (TIL) circumvents the need for CD83 expression on DC.

These DC are exposed to HIV-1 to examine if this can directly modulate their functions or interfere with their cross-talk.

We used dendritic cells loaded with anti-DEC205-antigen constructs, consisting of a single-chain variable fragment (scFv) directed against DEC-205, genetically linked to different parts of the MAGE-A3 model antigen (i.e. the KKl and EVDPIGHLY peptides), in a study to compare antigen-loading strategies.

My laboratory continued to analyse the ability of invariant NKT (iNKT) cells to assist priming of antigen specific T and B cell responses. We have demonstrated that activation of human DC by Toll like receptor ligands (TLR-L) modulates the lipid biosynthetic pathway, resulting in enhanced recognition of CD1d-associated lipids by iNKT cells; we have clarified the mechanisms by which CD1d-restricted lymphocytes translate T cell receptor (TCR) recognition of lipids with similar group heads into distinct biological responses; and we demonstrated that pathogen-derive...

Using pharmacological inhibitors, or macrophages and DC from mice carrying a null mutation in MAP kinase signalling molecule(s), we have evidence for a role of certain MAP kinases in the regulation of IL-10 and IL-12, IFN-gamma production.

We have investigated the in vivo capacity of resting (and of DC-primed) NK cells to reach the draining lymph nodes.

We have determined mechanisms for DC-induced Th1 development and the molecular pathways for inducing Th1 cells producing IFN-gamma solely, or Th1 cells producing IFN-gamma and IL-10, which have important implications for regulation of the immune response to eradicate pathogens with minimum pathology.

We are currently performing gene silencing experiments in human monocyte-derived DCs (MDDCs) with the dual aim of generating relevant knowledge on (i) the transcriptional regulation of DC differentiation, and (ii) the safe and rationale in vitro manipulation of gene expression in DCs.

These multipeptide loaded cytokine matured moDC +/- CD40L activation were used for the DERMA-ER-DC 04 trial.

For a transcriptional profiling of dendritic cells, DC were stimulated with PolyI:C, pretreated or not with PP2, and microarray analysis was performed.

To quantify presentation of the epitopes by DC, we used bulk T cells electroporated with TCR-encoding RNA in stimulation assays.

We have efficiently transfected DC with RNA encoding a functional protein (E/L-selectin), which allows entry of DC into LN from HEV. These DC rolled in vitro on sialyl-LewisX-coated slides, and in vivo, mouse E/L-selectin-transfected DC homed to LN after i.v. application.

Since LPS-activated DC are potent inducers of NK cell priming and lymph nodes appear to be a key place in which DC and NK cell interactions occur, we have investigated the in vivo capacity of resting and DC-primed NK cells to reach the draining lymph nodes.

Using pharmacological inhibitors, or macrophages and DC from mice carrying a null mutation in MAP kinase signalling molecule(s), we have evidence for a role of certain MAP kinases in the regulation of IL-10 and IL-12, IFN-gamma production.

The DC were matured with TLR ligand R848 and polyI:C. Using these DC, we obtained best results in our evaluation whether antigens could be rerouted from the endosomal into the cytosolic compartment by combining antigen with cell penetrating peptides to further enhance cross-presentation.

We have studied the immuno-physiology of rat and mouse intestinal dendritic cells. We have used a known adjuvant, E. coli heat-labile toxin (Etx) and a potential adjuvant R-848, a small TLR7/8 ligand.

We are defining the differential roles of intestinal lymph DC subsets in activation of naïve and memory T cells. Two of the three DC subsets are highly potent activators of naïve CD4+ T cells, and do not appear to be constitutively suppressed in any way.

We have electroporated these DC with melanoma antigen RNA for a cross-presentation study and showed that they express the proteins ex vivo and in vivo.

We observed that ICAM-1 expression by mature DCs is critical for long-lasting contacts with CD8+ T cells, but dispensable for short-lived antigen-specific interactions. Serial brief T cell-dendritic cell contacts induced early CD8+ T cell activation, proliferation and effector CTL differentiation in the first few days after immunization.