Activation of autologous or HLA-identical sibling cytotoxic T lymphocytes by blood derived dendritic cells pulsed with tumor cell extracts

This study describes the effect of dendritic cells (DC) pulsed with tumor c ell extracts on the induction and activation of autologous and HLA-identica l sibling tumor cell specific cytotoxic T lymphocytes (CTL). The subjects o f the study were patients with hematological malignancies (acute myeloid le ukemia, acute lymphoblastic leukemia, and multiple myeloma), and stem cell transplant donors. Although lymphocytes primed with non-pulsed DC did not s how definite cytotoxic activity against autologous or HLA-identical sibling patient tumor cells, both autologous and HLA-identical sibling CTL activat ed by DC pulsed with tumor cell extracts demonstrated markedly significant killing activity against tumor cells in the fashion of higher cytotoxicity with the increase of effector:target ratio (p<0.05). These findings reveal that DC pulsed with tumor cell extracts could be efficiently applicable in anti-tumor immunotherapy for patients with hematological malignancies.