Visualizing T-Cell Responses: The T-Cell PET Imaging Toolbox.

T lymphocytes are key mediators of the adaptive immune response. Inappropriate or imbalanced T-cell responses are underlying factors in cancer progression, allergy, and other immune disorders. Monitoring the spatiotemporal dynamics of T cells and their functional status has the potential to provide unique biologic insights into health and disease. Noninvasive PET imaging represents an ideal whole-body modality for achieving this goal. With the appropriate PET imaging probes, T-cell dynamics can be monitored in vivo with high specificity and sensitivity. Herein, we provide a comprehensive overview of the applications of this state-of-the-art T-cell PET imaging toolbox and the potential it has to improve the clinical management of cancer immunotherapy and T-cell-driven diseases. We also discuss future directions and prospects for clinical translation.