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The article introduces scientific conference papers on T cells and skin to be presented at the 22nd Scientific meeting 2014 of the Fondation René Touraine (FRT), a European non-governmental organization that promotes therapeutic progress in dermatology, on 5th December 2014 in Paris, France. Papers by researchers Shimon Sakaguchi, Federica Sallusto and Thomas Gebhardt are included. Specific topics include immune abnormalities found in atopic dermatitis and adoptive transfer of dendritic cells.

Please cite this paper as: Increased regulatory T-cell frequencies in patients with advanced melanoma correlate with a generally impaired T-cell responsiveness and are restored after dendritic cell-based vaccination. Experimental Dermatology 2010; 19: e213-e221. Abstract: Naturally occurring CD4+ CD25+ regulatory T-cell (Treg) activity is assumed to facilitate tumor development and progression. To elucidate the possible role of Tregs in the course of melanoma progression, we analysed the frequency of Tregs in the peripheral blood of patients at melanoma stages I-IV and in patients at melanoma stage IV that underwent dendritic cell (DC)-based immunotherapy. Using CD25, Foxp3, CD127 and HLA-DR as Treg associated markers, we observed increased Treg frequencies in patients at the late melanoma stage (stage IV) when compared to healthy donors. Accumulation of Tregs in patients with progressed melanoma correlated with a general reduction of T-cell responsiveness to the recall antigens tetanus toxoid and tuberculin-GT. However, DC-based immunotherapy not only restored antigen-specific immunity, but also decreased the frequency of Tregs in peripheral blood of patients with melanoma. These findings indicate that tumor progression in patients with melanoma result in general immunosuppression that is associated with Treg expansion in the periphery and can be overcome by DC-based vaccination. [ABSTRACT FROM AUTHOR]

Please cite this paper as: Enhanced T-cell activation by immature dendritic cells loaded with HSP70-expressing heat-killed melanoma cells. Experimental Dermatology 2010; 19: 108–116. Vaccination protocols that utilize dendritic cells (DCs) to elicit therapeutic immunity against tumors are the subject of intense research. Given that the capacity of DCs to cross-present antigens is physiologically low, there is considerable interest to develop strategies that enhance that pathway. In order to best exploit the enhanced cross-presentation of antigens bound to heat shock protein 70 (HSP70), we analysed melanoma cell preparations for their HSP70 expression. Western blotting revealed strong upregulation of HSP70 after heat-killing in contrast to UV-B irradiation. When the uptake of heat-killed necrotic cells by DCs at various levels of maturation was assessed, 61 ± 7% of immature DCs (iDCs) internalized fluorescence-labelled necrotic material. Apoptotic material from UV-B-irradiated cells was internalized by only 48 ± 5% of iDCs. Maturation-inducing cytokines did not affect the uptake when added simultaneously with the tumor cell preparations. Loading DCs with heat-necrotic or apoptotic melanoma cells slightly reduced CD83 expression while leaving CD208 (DC-LAMP) expression unchanged. As determined by IFN-γ-detecting enzyme-linked-immunospot assays, iDCs loaded with heat-killed melanoma cells activated autologous T cells most effectively when used without any further maturation, whereas DCs loaded with apoptotic material required maturation. In conclusion, HSP70-expressing melanoma cells could be generated by heat-killing. Loading iDCs with heat-killed melanoma cells resulted in a superior priming of autologous T cells in vitro. [ABSTRACT FROM AUTHOR]