Mature dendritic cells are superior to immature dendritic cells in expanding antigen-specific naive and memory CD8+ T cells.

BACKGROUND: For successful dendritic cell (DC)-based immunotherapy, it is critical to identify the most potent stage of human DCs, including immature DCs (imDCs) and mature DCs (mDCs).
MATERIALS AND METHODS: imDCs were obtained by culturing monocytes in the presence of GM-CSF and IL-4 for 5- 7 days and imDCs were further cultured for 24-48 h in the presence of TNFalpha, IL-6, IL-1beta and PGE2 to obtain mDCs. Melan-A- and EBV (BRF1) peptides were used and the frequency of antigen-specific CD8+ T cells was assessed using appropriate tetramers.
RESULTS: mDCs were potent antigen-presenting cells for the induction and proliferation of antigen-specific naive and memory CD8+ T cells and may overcome regulatory functions that suppress antigen-specific CD8+ T cells.
CONCLUSION: Our findings that mDCs can efficiently expand antigen-specific naive and memory CD8 + T cells have important implications in the development of vaccination strategies and support the use of antigen-loaded mature DCs in human clinical trials