CD28 and neoplasm: Likewise, in another study, enhanced “tumor sensing” has been shown by a two-target approach with T cells transduced with a chimeric antigen receptor (CAR) of suboptimal activation properties binding to PSCA and a chimeric costimulatory receptor (CD28/4-1BB) binding to PSMA, where co-transduced T cells destroyed only tumor cells co-expressing both antigens [35].