A population of mature polarized dendritic cells with potent immunostimulating activity. Treating bone marrowed-derived dendritic cells (DCs) with interferon-alpha (IFN-a), polyinosinic:polycytidylic acid (poly I:C) and bacterial CpG-DNA produces mature but not exhausted alpha type-1 polarized DCs (alphaDC1) that are capable of: 1) high responsiveness to other lymphoid chemokines, and 2) producing high levels of interleukin-12p70 (IL-12p70), characteristics found in human type-1 polarized dendritic cells. When pulsed with specific tumor associated antigens (TAAs), alphaDC1 may induce a potent cytotoxic T lymphocyte (CTL) response against TAA-expressing tumor cells.