HAVCR2 and neoplasm: Tumour-bearing Cd4crePtger2−/−Ptger4fl/fl mice treated from day 6 onwards with the S1P1R antagonist FTY720, which prevents lymph node (LN) egress of newly primed CD8+ T cells31, showed unabated intratumoural development and prominent expansion of TIM-3+ TILs over time (Fig. 2k–m).