Harnessing dendritic cells for innovative therapeutic cancer vaccines

Purpose of review The clinical activity of new immunotherapies in cancer, such as anti-Programmed cell death 1 (PD-1)/Programmed death-ligand 1, has revealed the importance of the patient's immune system in controlling tumor development. As in infectious diseases, dendritic cells (DCs) are critical for inducing immune responses in cancer. Unfortunately, autologous DC-based vaccines have not yet demonstrated their clinical benefit. Here, we review recent research using allogeneic DCs as alternatives to autologous DCs to develop innovative therapeutic cancer vaccines. Recent findings A novel approach using an allogeneic plasmacytoid dendritic cell (PDC) line as an antigen presentation platform showed great potency when used to prime and expand antitumor-specific CD8+ T cells in vitro and in vivo in a humanized mouse model. This PDC platform, named PDC*vac, was first evaluated in the treatment of melanoma with encouraging results and is currently being evaluated in the treatment of lung cancer in combination with anti-PD-1 immunotherapy. Therapeutic cancer vaccines are of particular interest because they aim to help patients, to mount effective antitumor responses, especially those who insufficiently respond to immune checkpoint inhibitors. The use of an allogeneic plasmacytoid DC-based platform such as PDC*vac could greatly potentiate the efficacy of these new immunotherapies.