Imaging of Activated T Cells

Abstract

The adaptive immune response plays a critical role in detecting, eliminating, and creating a memory toward foreign pathogens and malignant cells. Demonstration of the specific and effective target killing of T cells in cancer has reignited interest in the study and therapeutic manipulation of the interaction between tumor and immune system. To both improve therapeutic efficacy and reduce adverse events, accurate monitoring of the activation of T cells is required. Several approaches to monitoring not just the presence, but importantly the activation, of T cells have been developed. Here, we review the recent advances in T-cell activation imaging and future directions for potential implementation into clinical utility.

Keywords: PET; T cells; cancer; immunotherapy.

FIGURE 1.

Graphical representation of T-cell activation and corresponding PET imaging agents. Cross-priming of naïve T cells (top left) leads to activation (top right). On recognition of cognate antigen, functional release of granzyme B and IFN-γ is induced (bottom). GRIP = granzyme targeting restricted interaction peptide specific to family member B; mAb = monoclonal antibody; MHCI = major histocompatibility complex I; TCR = T-cell receptor.