Fig. 1
From: Promise and challenges of clinical non-invasive T-cell tracking in the era of cancer immunotherapy
Principle of non-invasive in vivo imaging of lymphocytes trafficking to and into the tumor. Activated tumor-reactive T-cells are intravenously injected into a patient having a tumor specifically recognized by those T-cells. The accumulation of the T-cells within the tumor is visualized in-situ using radiolabelled probes recognizing specific markers expressed on the T-cell membrane. The radioactive probe targeting T-cells can be either a full-size antibody and its derivatives, or a short peptide radiolabelled with a radioisotope (PET or SPECT isotope) matching the plasma half-life of the probe