These patients undergo leukapheresis and later intradermal administration of the produced vaccine (V administrations of autologous dendritic cells generated from adherent peripheral blood monocytes and subject to quality controls - with eventual additional ones depending on clinical outcome).

Hu-SCID mice were used to study responses to EBV and HIV.

The mice were infected with EBV and mount an immune response (i.e. cytotoxic T cell proliferation, some control of EBV driven B cell proliferation, perforine and granzyme expressing T cell infiltration in B cell infected areas in lymphoid organs in situ), however, specific T cells could not be detected directly ex vivo by looking at the most common EBV derived/presented epitopes (tetramer staining). Some animals developed EBV induced B cell lymphoproliferative disease.

These mice were infected with both CXCR4 as well as CCR5 tropic HIV-1 strains. HIV causes a disseminated infection and spreads in all newly generated lymphoid tissues, thus closely resembling HIV infection in humans. We are now aiming to improve the recipient mouse background by co-transplanting human mesenchymal stroma cells, and by adding human cytokines as well as human MHC. Furthermore, we use the mice to evaluate targeted therapies directed at human immune system cells as T cells, B cells, and dendritic cells.

We established “human hemato-lymphoid-system mice” by transplanting human CD34+ cord blood cells into irradiated newborn Rag2-/-gc-/- mice, leading to de novo development of human B, T, and dendritic cells.

This patient has received 9 vaccines with peptides only in a randomized trial to receive immunizations either with I3 DC (DC generated with interferon-beta and interleukin-3) or with G4 DC (DC generated with GM-CSF and IL-4). Up to now, in Cycle 3, immunizations have been continued with peptide-only injections of all 9 peptides except Tyrosinase at 12 weeks intervals. For the continuation of the vaccinations the clinicians have decided to inject the patient at 6 months intervals. The patient who clinically showed Partial Response at the end of cycle 1 is curre...

IDO appears critical for the regulation of TNBS colitis upon CTLA-4 engagement, as the beneficial effect of anti-CTLA-4 treatment was lost in IDO-deficient mice. By contrast, the absence of IDO did not alter the course of inflammation in mice injected with TNBS only, an unexpected finding which suggests that IDO-dependent counter-regulation requires other factors/cells in addition to IDO production and T cell activation by TNBS.

These K/O mice were studied with regard to responses to viral infections. We used the mouse pox virus Ectromelia and MVA-BN. Coinfection with MVA-BN and Ectromilia protected the IFNalpha receptor -/- mice. The data show that MVA-BN can induce potent innate immune responses able to control viral replication to allow the specific immune response to eliminate Ectromelia in immune deficient mice.

Antigen-specific CD4+ T cells were followed in these immunized individuals using generated peptide-MHC class II multimers.

By immunizing mice with ovalbumin-conjugated anti-Siglec-H Ab in the presence of CpG, we demonstrated generation of antigen-specific CD8 T cells in vivo.

A recombinant Leishmania major parasite expressing a fluorescent tracer was used for the infection of BALB/c (H2-d) mice. This was done to investigate whether infected DC process pathogen-derived antigen and stimulate antigen-specific CD4+ T cells in vivo.

This patient experienced an outstanding response to immunotherapy. The patient received several adoptive T cell transfers and regressed from stage IV melanoma to a disease free state and has remained tumor free for several years.

In these patients, dendritic cells were tracked for monitoring of cellular therapy by MRI. MRI cell tracking using iron oxides appears clinically safe and well suited to monitor cellular therapy in humans.

This HSV vector expressing full length tyrosinase, gp100 and MART-1 was used to transduce dendritic cells from melanoma patients which were then to be used for vaccination.

A significant number of patients was enrolled in the DC-based immunotherapy trial. After vaccination, vaccine-induced depigmentation and vitiligo were observed.

Small cohorts of patients (3-9) were vaccinated with differently composed DC-vaccines: DC loaded with a single MAA-derived peptide (MAGE-3.A1 or -A2 or Na17.A2) or pulsed with 2 to 3 MAA-derived peptides (combinations of MAGE-3.A2, MAGE-C2.A2 or Na17.A2) or G4-DC loaded with 8 different peptides. An important conclusion that can be made from these pilot-observations is that the potential therapeutic effect of our DC-based MAA-vaccination approach does not occur instantly but is delayed by 8-12w following the first vaccination (i.e.12-16w after the isolation o...

Patients with stage III or stage IV melanoma who undergo surgical resection of a melanotic lesion. These patients are vaccinated with pulsed and thouroughly tested dendritic cell vaccine.

DC-based vaccines that were given to these patients were combined with low dose IFN-alfa (3 x 10e6 U per wk). In a number of patients we observed vaccine-induced depigmentation and vitiligo.

A vaccination trial with RNA transfected autologous DC was done with overlapping peptides covering the whole protein sequence of the tumor antigens MageA3, MelanA and Survivin. With this approach we monitored the immune responses of 8 vaccinated patients and of more than 15 other stage IV melanoma patients.

These patients were treated with monocyte-derived DCs matured with inflammatory cytokines and subsequently electroporated with mRNA encoding 6 tumor-associated antigens.