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.

These DC were matured using CpG-DNA as TLR9 ligand. Mature DCs upregulated CD80, CD86, MHC class II and produced cell type specific cytokines. Matured pDCs pDCs produced type 1 Interferons.

The question was addressed of whether bLf, whose immunomodulant properties are now recognized, could influence MDDC differentiation/activation.

We investigated the interactions between human monocyte derived DCs (MDDC), generated in the presence of GM-CSF and IL-4 (IL-4 DC), and antigen-stimulated circulating gamma delta T lymphocytes, bearing the Vgamma2 TCR.

Cells are separated into lymphocytes (and monocytes) by elutriation in a closed system (Elutra). [The fraction richest in lymphocytes contained > 90% lymphocytes and viability was > 95%.]

These DC were matured using CpG-DNA as TLR9 ligand. Mature DCs upregulated CD80, CD86, MHC class II and produced cell type specific cytokines. CD8+ myeloid DCs “cross-presented” exogeneous Ags (Ovalbumin).

We found that LPS-stimulated mDCs are able to induce up-regulation of co-stimulatory molecules on co-cultured pDCs. Likewise, CpG-stimulated pDCs activate co-cultured mDCs. The cross talk between these two populations of DC is very efficient since it can be observed at mDC/pDC ratio ranging from 1/10 to 10/1.

These cells are prepared from the removed lesion from patients with stage III or stage IV melanoma and are subsequently used to pulse a portion of the immature dendritic cells.

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.

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...

Monocytes were isolated from PBMC to generate dendritic cells.

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.

It was found that lymph nodes that drain sites of mature DC or adjuvant inoculation recruited L-selectin- CCR7- effector cells.

By selecting for cytokine receptor expression relevant to DC development, we were able to identify highly cycling Lin–c-KitintFlt3+M-CSFR+ cells with a distinct gene-expression profile in mouse bone marrow that, on a clonal level in vitro and as a population both in vitro and in vivo, efficiently generated plasmacytoid and conventional DCs but no other lineages, which increased in number after in vivo injection of the cytokine Flt3 ligand.

Indium labelled E/L-S DC (without antigen loading) is administered i.v. to a patient to study the reaction with regard to DC migration.

These DC were used to elicit CTL responses in a mouse model.

These DC were used in a maturation step for subsequent production of a DC vaccine.

These DC were generated by culturing enriched monocytes for 5 days.

These cells do not acquire a mature phenotype and do not lead to an enhanced secretion of several cytokines/chemokines.