To investigate whether we could create FP T cells that mediate tumor killing using the same principle as bispecific antibodies, we knocked‐in a TAG‐72 scFv and a (G4S)3 linker into the N‐terminus of the CD3ε gene, linking the scFv with the CD3ε signaling subunits of the TCR complex to generate TAG‐72/CD3ε FP T cells (Figure 1a). Here, CD3E is linked to neoplasm.