In vivo monitoring of cancer specific TCR-engineered human T cells by Immuno-PET to analyze pharmacokinetics of T-cell based immunotherapies

In vivo imaging of T cells genetically modified by tumor specific T-cell receptors (TCR) may improve the understanding of T-cell distributions during immunotherapy. We targeted TCR-transgenic effector cells by a Zirconium-89 labeled F(ab’)2 specifically binding to the introduced TCR. TCR-transgenic T cells were tracked at the tumor site in a xenogenic mouse model by positron emission tomography. We detected diverse distribution patterns depending on the tumor size and rejection phase correlating to histologically confirmed T-cell infiltration. This technology may be critical for monitoring and optimization of immunotherapies.