Transfected human dendritic cells to induce antitumor immunity

Dendritic cells are professional antigen-presenting cells able to prime nai ve T lymphocytes and regulate steadily the delicate balance between toleran ce and activation during the immune response. in past years several reports have shown that genetically engineered dendritic cells (DCs) can be a powe rful tool for inducing an antigen-specific immune response. The use of such modified antigen-presenting cells is a real working hypothesis in preclini cal studies and in clinical vaccination approaches for cancer treatment. Th e definition of optimal transfection conditions for preserving DC survival and functionality is necessary to design a correct immunotherapeutic protoc ol. Different lipid-based transfection compounds were studied for their eff ects on DC survival, phenotype and functional properties. Ali the transfect ion procedures were able to select DCs with a higher expression of activati on and costimulatory molecules (ie MHCII-DR, CD83, CD86, CD25) than the unt reated DCs. However, only two compounds (LipofectAMINE PLUS and FuGENE 6), preserved or even increased the immunopotency of DCs as antigen-presenting cells. These protocols were applied to modify DCs in order to express an ep ithelial tumor-associated antigen, MUC1, and such cells were able to induce in vitro a specific immune response in healthy donors.