While TILs from human bladder tumour predominantly co-expressed CTLA-4 and PD-1 (Fig. 1a), 25% of TILs from murine MB49 tumours co-expressed CTLA-4 and PD-1 with additional 36 and 4% expressing either PD-1 or CTLA-4 alone (Fig. 1b). Here, CTLA4 is linked to neoplasm.