We have demonstrated that the NADPH oxidase NOX2 is recruited to DC early phagosomes mediating a sustained production of low levels of reactive oxygen species and causing a maintained alkalynization of the phagosomal lumen. DCs lacking NOX2 show increased antigen degradation due to an enhanced phagosome acidification. As a result, the efficiency of in vitro and in vivo antigen cross presentation is significantly reduced in NOX2-deficient DCs.

Direct administration of ovalbumin (OVA) encoding lentiviral vectors caused in vivo transduction of cells that were found in draining lymph nodes (LNs) and induced potent anti-OVA cytotoxic T cells similar to those elicited by ex vivo transduced DC.

Direct administration of ovalbumin (OVA) encoding lentiviral vectors caused in vivo transduction of cells that were found in draining lymph nodes (LNs) and induced potent anti-OVA cytotoxic T cells similar to those elicited by ex vivo transduced DC.

These mice were studied with regard to responses to viral infections and compared to TLR K/O mice. We used the mouse pox virus Ectromelia and MVA-BN.

These K/O mice were studied with regard to responses to viral infections. We used the mouse pox virus Ectromelia and MVA-BN.

We have analyzed the uptake, conservation and cross-presentation of the model antigen OVA after Fc receptor-mediated uptake by DC. We found that MHC class I presentation is relatively short-lived in contrast to MHC class II. However, CD8 cross-priming capacity of OVA-loaded DC was functionally retained for many days, while peptide-pulsed DC had lost their priming capacity after 24 hours.

We have analyzed the uptake, conservation and cross-presentation of the model antigen OVA after Fc receptor-mediated uptake by DC. We found that MHC class I presentation is relatively short-lived in contrast to MHC class II. However, CD8 cross-priming capacity of OVA-loaded DC was functionally retained for many days, while peptide-pulsed DC had lost their priming capacity after 24 hours.

Stimulation of Mycobacterium tuberculosis (MTb)-antigen specific T cells ex-vivo in the presence of anti-IL-10 antibodies results in their increased proliferation and IFN- production.

Dendritic cell (DC) derived-exosomes (Dex) were described as nanovesicles harbouring functional MHC molecules stimulating T cell responses. Mouse studies unraveled the bioactivity of Dex onto NK cells, Dex promoting a IL-15Ra-dependent NK cell proliferation and a NKG2D-dependent activation resulting in an anti-metastatic effect. In humans, Dex bear functional IL-15R? which allow proliferation and IFNg secretion by NK cells. In contrast to immature DC, human Dex harbor NKG2D ligands on their surface leading to a direct engagement of NKG2D and NK cell activation ...

We have generated a monoclonal antibody, 2C44, that reacted to a peptide derived from the Leishmania LACK protein bound to I-Ad MHC class II molecules. We have successfully used the 2C44 mAb to visualize LACK-presenting DCs in mice infected with the L. major.

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.

Co-culture of immature DC with TIL or K562 cells overexpressing CD83 results in the production of enhanced levels of pro-inflammatory cytokines, whereas this production is less pronounced or even absent in co-cultures with non-modified TIL or K562 cells.

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

Down-regulation of CD83 expression on human DC through RNA interference (RNAi) results in a less potent induction of allogeneic T cell proliferation, reduced IFN-gamma secretion by established T cells and decreased capacity in the priming of functional tumor antigen-specific CD8+ T lymphocytes.

We wanted to assess whether functional activation of human monocyte-derived DCs can be achieved by electroporation of an activation signal in the form of double-stranded (ds) RNA and whether simultaneous electroporation of the dsRNA with tumor antigen encoding mRNA can lead to the induction of a cytotoxic T-lymphocyte (CTL) response.

These T cells were associated with multiple markers into 14 different cell types to identify subsets. The findings thus describe new CD8+ cell subsets, allow the identification of relatively homogeneous CD8+ subpopulations, provide a predictable and precise correlation between particular cell surface markers and CD8+ T-cell functional properties, and identify effector cells present in both CCR7-CD45RA+ and CCR7-CD45R0+ compartments. The results also indicate that activated cells might modulate the expression of CD45RA/R0 asynchronously rather than CCR7-CD45...

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 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.

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.

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