Co-culture with any of the 3 retinoblastoma cell lines consistently induced TIM3 expression in approximately half the T cell population, while PD1 expression remained below 15% in every case excluding an inhibitory impact on CAR-T cell function by the PD1/PDL1-axis in our in vitro model (Fig. 2d). Here, HAVCR2 is linked to retinoblastoma.