Progress in the Development of Immunotherapy of Cancer Using Ex Vivo-Generated Dendritic Cells Expressing Multiple Tumor Antigen Epitopes

Immunotherapy with tumor-associated antigen-pulsed, ex vivo-generated dendritic cells (DCs) is a promising approach for the treatment of cancer that has shown efficacy in animal models and is now being tested in the clinic. The majority of studies performed to date make use of a single tumor-associated epitope. However, because of the high rate of mutation in tumor cells allowing for loss of expression of a single antigen, it is likely that use of multiple antigenic epitopes will induce a broader, longer-lasting, and effective tumor-specific immune response. Multiple vehicles for loading DCs with multiple antigenic epitopes are under investigation to determine the most effective method for vaccination, with many of these methods showing promise. These loading methods, as well as other critical considerations for making DC vaccination as efficacious as possible, are discussed in this article.