CD28 and neoplasm: Lisocabtagene is comprised of a murine extracellular scFv of the FMC63 monoclonal antibody that binds to CD19 on tumor cells followed by a human IgG4 hinge region, CD28 transmembrane domain fused to the costimulatory molecule 4–1BB (CD137), and the T cell activation domain CD3ζ chain (40).