IFNG and neoplasm: Nonetheless, the higher frequency of intratumoral CAR-o9R cells expressing IFNγ (Fig. 3k) and the superior direct in vitro cytotoxicity of CAR-o9R cells (Fig. 3c) indicate that superior intratumoral potency—rather than tumour infiltration or proliferation—drives the anti-tumour efficacy of CAR-o9R T cells in the context of tumour-restricted orthogonal cytokine signalling.