DENDRITIC CELLS - POTENTIAL ROLE IN CANCER-THERAPY

Dendritic cells (DC) are extremely potent antigen presenting cells, un iquely capable of sensitizing naive T cells to protein antigens and el iciting antigen specific immune responses. Studies of human DC isolate d from peripheral blood indicate that these cells can be used to stimu late and expand antigen specific CD4+ and CD8+ T cells, in vitro. On t he basis of these findings we have initiated pilot clinical studies to investigate the ability of DC pulsed ex vivo with tumor associated pr oteins to stimulate host anti-tumor immunity when re-infused as a vacc ine. In the first such study DC pulsed with tumor derived idiotype pro tein were infused into patients with low grade malignant B cell lympho ma who had failed conventional chemotherapy. The majority of treated p atients developed T cell mediated anti-idiotype immune responses and s ome of the patients experienced tumor regression. These results sugges t that DC based immunotherapy is a potentially useful approach to B ce ll lymphoma and raises the possibility that the approach may prove use ful in the treatment of other tumors as well.