Figure 1. The not enough of a good thing paradigm.
APCs (especially DCs) capture antigen from tumor cells. Antigen-loaded APCs then prime naive T cells to become antitumor CTLs through soluble mediators such as IL-12 and/or cosignaling molecules such as CD80 or CD86. Failure to elicit protective immunity is seen as a lack of sufficient quantity or quality of 1 of these events (indicated in red text). This model predicts that augmenting numbers or quality of a specific component will suffice as a clinical strategy.
