Radiopharmaceuticals for imaging T-cells

In vivo tracking T-lymphocytes is dramatically advancing our understanding of the complex immune landscape in a wide spectrum of autoimmune and cancer diseases. By providing new insights into intricate mechanisms, pathways, molecular interactions and dynamic nature of immune system, this approach paves the way for personalized therapies, tailored to individual patient need. Imaging T-cells is, indeed, emerging as a crucial tool not only for early disease detection, but also for personalized immune-therapy and treatment monitoring, thus enabling a "precision medicine". T-lymphocytes offers several accessible molecular targets suitable for immune-imaging, including the well-characterized CD3, CD8 and CD4 surface markers. Consequently, significant efforts have been, and currently are, devoted to develop highly sensitive and specific radiopharmaceuticals for single photon emission tomography (SPECT), positron emission tomography (PET). These advanced tools aim to non-invasively visualize and quantify these key targets and to assess the functional status of T-lymphocytes within tumor microenvironment or sites of autoimmune inflammation. This narrative review aims at providing a deep overview of the main strategies adopted so far for imaging T-cells and their subsets, emphasizing current and prospective clinical applications in autoimmune diseases and immune-oncology. Furthermore, advancements and challenges in successfully translating these approaches into clinical practice will be also discussed. We will discuss the great potential of T-cells imaging to significantly improve patient's outcome and revolutionize the management of these challangind diseases.