Tisagenlecleucel consists of a murine scFv of FMC63 monoclonal antibody that binds to CD19 on tumor cells and is fused to the CD8α hinge and transmembrane regions followed by the costimulatory molecule 4–1BB (CD137) and the T cell activation domain CD3ζ chain (31, 40). The gene discussed is CD19; the disease is neoplasm.