TLR9 and neoplasm: Mice that were immunized with OVA plus CpG-B (synthetic TLR9 ligand) and possessed pDCs lacking MHC class II molecules showed reduced numbers of IL-17-secreting OT-II cells, exhibited a significant increase in tumor growth, and showed a reduction in the recruitment of tumor-specific cytotoxic T lymphocytes (CTLs) into tumors (80).