Development of antitumor cellular immunity

Abstract

A dazzling picture of many different types of innate and adaptive immune cells that have infiltrated a patient's tumor emerges when a tumor section is studied under the microscope. There is good evidence that patient survival depends on the numbers, type, character and localization of particular tumor-infiltrating immune cells, in particular T cells and macrophages. Here we discuss the events governing the arousal of a spontaneous tumor-specific T cell response and how the tumor-rejecting efficacy of this T cell response is regulated by the intratumoral cytokine milieu, the expression of inhibitory molecules and co-infiltrating immune cells. Finally, we describe approaches to change the local micromilieu so that the net outcome is a strong induction of an anti-tumor immune response coupled to a better infiltration of tumors under conditions that allows these immune cells to exert their function and to control tumor outgrowth.