AXL and neoplasm: Jurkat T cells expressing the Axl synNotch were activated and produced BFP only when co-cultured with Axl+ K562 tumor cells for 24 hr (Fig. 4E), whereas cells containing tTA responsive element without the Axl SynNotch did not have high BFP expression (control, Fig. 4E) even when co-cultured with Axl+ tumor cells.