Plasmacytoid dendritic cells (pDCs) are not only potent inflammatory cytokine producers but also function as antigen-presenting cells (APCs). We have shown that vaccination using CpG-B activated tumor antigen (Ag) presenting pDCs induce Th17 cells that promote intratumoral immune cell recruitment, including antitumor cytotoxic T lymphocytes CTLs. Therefore, strategies targeting both innate and adaptive pDC functions may improve antitumor T-cell immunity.