The quantity and quality of tumor-reactive T cells can be measured and tracked in order to anticipate how well cancer immunotherapy will work.378,515,516 A multiparameter phenotypic and functional readout of T cell reactivity will be likely necessary in the absence of extensive evaluation using several types of T cells and APCs.380 Numerous effective markers, including CD39, PD-1, TIM-3, OX40, 4-1BB, IFNγ, and TNFα, can be used to determine the proportion of neoantigen-reactive T cells in infusion products and their capacity to recognize autologous tumors. The gene discussed is HAVCR2; the disease is neoplasm.