T-cell tracking using Cerenkov and radioluminescence imaging.

Cancer immunotherapy is a promising strategy based on the ability of the immune system to kill selected cells. In the development of an effective T-cell therapy, the noninvasive cell tracking methods play a crucial role. Here, we investigate the potentialities of T-cell marked with radionuclides in order to detect their localization with imaging techniques in small animal rodents. A protocol to label T-cells with P-ATP was tested and evaluated. The homing of P-ATP labeled T lymphocytes was investigated by Cerenkov luminescence imaging (CLI) and radioluminescence imaging (RLI). The first approach relies on the acquisition of Cerenkov photons produced by the beta particles emitted by the P internalized by lymphocytes; the second one on the detection of photons coming from the conversion of radioactive energy in light done by scintillator crystals layered on the animals. The results show that T-cell biodistribution can be optically observed by both CLI and RLI in small animal rodents in in vivo and ex vivo acquisitions. T-cell localization in the tumor mass was definitively confirmed by flow cytometry.