CD28 and mesothelioma: In vitro, human CAR T cells prepared with either high-affinity 4m5.3 or lower-affinity E2 scFv-based CARs exhibited potent cytotoxicity against amph-FITC-tagged MSTO-211H human mesothelioma tumour cells, irrespective of the use of CD28 or 4-1BB co-stimulatory domains (Extended Data Fig. 5a).