Dendritic cell-based cancer immunotherapies

Because of their unique role in linking the innate and adaptive immune systems, dendritic cells (DCs) have been a logical focus for novel immunotherapies. However, strategies employing active immunization with ex vivo generated and antigen–pulsed DCs have shown limited efficacy in clinical trials. These past approaches did not take into account the complex interactions between cells of the innate immune system and DCs during DC maturation, antigen processing, and presentation to naive T cells. By better understanding the natural sequence of events occurring in vivo during an effective immune response, we can tailor antitumor immunotherapeutic strategies to augment aspects of this response from the activation of innate immune cells to antigen uptake and DC maturation to priming of naive T cells and, ultimately, to the establishment of antitumor immunity. Current DC vaccination strategies utilize a number of methods to recapitulate the cascade of events that culminate in a protective antitumor immune response.